Anile8er
09-12-2003, 06:55 AM
while cleaning my bakup i found this
Recipe for 500 Horsepower, 22 MPG. Long.
Engine Buildup. High performance, Street.
Today’s project: Small block Chevy 355 with a Blower
Target TQ/HP goal: 520TQ/500HP (nice and rounded)
Target Mile per Gallon Goal: 21 MPG (nice and… err... nice)
Target Terrain: Mainly Street, “stoplight racing”, strong 0-60, very strong 0-140 MPH, occasional ¼ at the track.
Target Drivability goal: Mild idle quality, no rough stuff, powerful off the line TQ, excellent response and driving quality, good brakes (heh), and yes we want economy.
Engine block: 1976 (Pre-86) block. .030 Over (355 CID)
Had machine shop Bore, Hone, Clean, Acid Wash, Align BORE and align HONE, then new freeze plugs/cam bearings, and finally, all threads chased and cleaned.
Rotating assembly:
Factory Forged Crankshaft (or aftermarket Forging, 4340 Steel is ideal, Eagle is affordable and recommended.) ours was .010/.010 on the journals to make sure all was perfectly round. Even aftermarket cranks can be egg-shaped or worse, a good 10/10 is recommended to keep things perfect. It is believed that going more than 10/10 is bad on any forced induction motor, I have found this to be incorrect. There is plenty of material left to go 50/50 or further, depending on application. It’s not recommended however, but it’s been done.
TRW Flat tops with D-Cup valve relief (forced induction type) 9.8:1 comp with 68CC head, 8.6:1 comp with 76CC head, and 9:1 comp with 72CC head.
Eagle Forged 4340 5.7” H-Beam rods. 650 Grams each (a little heavy), minor block grinding needed to fit. Used air-grinder to make things simple. Strong, and affordable.
Rings were File fit Federal Moguls, each top and mid rings filed to .28-.30 gap. (Good for forced induction/nitrous. If forced induction/nitrous isn’t to be used, a gap of .25~ is sufficient for the top and .23~ for the bottom.)
Bearing were Clevite 77’s, 10/10 of course to fit journals. A slightly thicker bearing (10/10) is better because there is more bearing to wear before the journals begin to fatigue.
We used ARP bolts on the entire engine, and Studs instead of bolts wherever possible. The crankshaft main caps were no exception. Four-bolt Mains, ARP Studs, with Windage tray provisions. A moroso windage tray was used, but needed to be modified (cut) to fit the stock Oil pan we used. It would hit the rods (H-beams are so big!) so we also… modified… (Ok, we banged it up), to fit…
Total cost of engine so far:
Block ($150 + machine shop labor ($200) = $350 (machine shop had block)
Crank (eagle) = $650 (summit)
Rods (eagle) = $400 (summit)
Pistons (trw) = $320 (summit)
Rings (FM) = $110 (summit)
Bearings (clevite) = $35 (Murray’s)
Studs (Arp) = $65 (summit)
Oil pan (stock) = $100 new (summit)
Oil pump (FM) = $65 with pickup *(summit)
Windage tray (moroso) = $30 (Murray’s)
Shipping for products = $65
Total for Bottom end: $2190
So now we have ourselves a strong, forged, abusable bottom end. Remember, the less we abuse it now, the longer it will last. This engine combo should be good for about 250,000 miles if treated properly, likely more if well maintained. This, in a street environment, is considerable. Our camshaft however, will be flat tappet, thus will likely need replacing sometime around 100K miles, this being the nature of high-life tappet camshafts. Ill explain later….
Now for the most important part, our horsepower making combo, and the reasons behind the economy / power selection.
Comp cams Custom grind
Camshaft: Advertised duration: (or “seat to seat”) 274/286. Advertised Lift: .323/.333, 114 Lobe separation Angle, 5* of ground in advance (109 Lobe centerline)
.050 - .050 duration: 219/228, lift after 1.5 rockers: .484/.500
Power band: 1500-5500 Rpms Vacuum: 15” @ 600 RPMS, 18” @ 800 Rpms
We chose this cam for several reasons… the obvious ones being streetability and idle vacuum/quality. Unobvious reasons? Economy, blower friendly, throttle response. Okay maybe those WERE obvious, no need to rub it in my face. The wide 114 LCA give us boost trapping ability, as well as the ability to trap the most fuel during a highway cruise. The low .050-.050 duration means we get the most of our torque friendly blower, and it also means we get to use our power brakes! Yay! And if you don’t get that, you have never drove a car with a Chevy 350 that had more than 240* of .050-.050 duration on the street.
Now let’s get down to business. No one probably told you this but it’s the heads/cam/intake that makes power. They did? Oh well, but its true. All the forged bottom end parts in the world won’t make your Chevy go any faster. In fact, those 650 gram eagle H-beams only slow it down, they are so big and heavy! But that’s ok, because volumetric efficiency is on our side.
For heads, there are several affordable choices. Our choice was AFR’s 190CC Street heads. A very important thing to realize in a head that will see boost in, is the ability to flow exhaust out. And AFR’s 190CC street heads do that considerably well. Other choices would be brodix track 1’s, Dart 200CC, or even Edelbrocks Performer RPM series. Porting? Unnecessary, but in your best interest if you run at the track a lot. Porting will improve your numbers, but will hurt your street drivability. Things that can’t hurt on the street: 3-angle “street” valve job, Blending of bowl area, exhaust porting, gasket matching (cutting your intake/head gasket ports to the EXACT size of the actual port) and so on… find a reputable machine shop and they can lead you in the right direction.
Head gasket is a Fel-pro steel ringed gasket
Head Studs are ARP and properly torqued down
Now, we have heads and a Cam. What about the intake? Oh yeah, our blower COMES with an intake! How nice! Say, does that make the blower the plenum? Hmm…
Our blower is a Weiand 177 Satin-finish Roots’ style blower.
Total Cost so far:
Camshaft (comp) = $212
Heads (AFR 190) = $1395
Blower (Weiand 177, summit) = $1850
Gaskets / materials (thread sealer, loctite, oil, gaskets etc) = $150
Shipping = $65
Total engine cost so far: priceless (just kidding) $3672 + 2190 = $5862
So let’s say $6000 so far invested into our engine. This is everything bought new, in the box, never touched. You can bring this number down quickly by using used parts and rebuilt parts, but we chose to use everything new simply for longevity reasons.
You can now, if you want to, slap a carburetor on this blower (a 750 vacuum secondary would be nice) and go go go. You would make about 500 horsepower/ 500 Ft. Lbs. yes. But economy? You would get maybe, in a non-overdrive car with a decent gear (3.23-3.42) and proper vacuum advance timing maybe 15-17 MPG. Not bad eh? But where do we come up with the 21 MPG? And what about the extra throttle response / driveability/ street friendly ness? I’m about to show you the wonders of DFI.
Holley Performance sells a complete Kit called the “Commander 950 Throttle Body Fuel injection kit” It comes with everything you need (almost… sigh*) to throw a fuel injection setup on top of your blower. Outstanding throttle response, extra horsepower, and tons more fuel economy and cruiseability can be achieved using this fuel injection setup. You even are required to initially program it using your laptop computer. You control the fuel, and the spark… even under boost you can set the parameters for how much fuel you want to add. I don’t work for Holley, but even if I did, I would still say about the same things I'm saying now. And the price? Ha! That’s the best part. It’s the cheapest fuel injection kit I’ve yet to see, and the easiest to use!
Complete Kit: $1395
Just plug it all up and into your laptop, download a few of the base fuel maps from Holley’s site, and start tuning to your engine’s desire. No more jet changes, no more worry about extra fuel under boost, no more timing light issues, no more detonation concerns, no more blown power valves (thanks Holley!) you can even save different profiles (like one for 87 Octane and one for 93 octane… and even one for 113 octane if you want!) its like a street racers dream come true. Ah... the powers of DFI. And then you can be like “The fast and the furious” with your laptop computer controlling your fuel flow… ah but it works!
Now we have the efficiency of DFI, the power and durability of an all forged/blown Chevy 355, what now? Well now we want MORE ECONOMY and MORE POWER so we look closer at our drive train. What’s this? A TH350 tranny? That has to go. And what else? A 3.73 geared 10 bolt? We will see, yes we will see.
To get the most bangs for our buck (literally) we want overdrive. Yes this means switching to the weaker and not-so-loved 700R4 (or 200R4) but it also means gobs less money spent at the gas stations… We want a BUILT and EFFICIENT transmission, not a stock one. Since our engine makes power RIGHT off idle, stall speeds can be kept very conservative. Since our engine makes GOBS of low end torque, we need a healthy “safe” gear to back it up. Expect to spend about $1300 on a healthy “built to the max” 700R4, and about $650 on a ACT/Yank/vigilante LOCKUP (important)9.5” torque converter. Why lockup and why 9.5”? Well first off LOCKUP will improve your highway MPG considerably, and it will also keep the converter cooler. Why 9.5”? well its been tested and re-tested, but a 9.5” Converter has MUCH higher efficiency at multiplying torque than any 10” or 12” converter, and not to mention LIGHTWEIGHT (can we say “rotating mass is bad”?) the 9.5” just blows away all other converter, and on top of that the lockup “plate” acts as an anti-balloon shield against all that tire shredding torque. You can even spray nitrous and the converter will be the last thing left after everything else went boom. Maybe. But anyways, long story short, 700R4 + 9.5”low stall (2400/2800) converter + lockup = fuel economy! Yes! 21 MPG + can be achieved with this plus the DFI above! Gearing? We don’t need 3.73s to get this baby moving! 3.42’s are the max I would recommend. 3.23s are probably the mainstream for this combo, but for plain street nothing beats a nice set of 3.42’s with that ultra low first gear in the 700R4 (3.06:1) its like having a TH350 with 4.11 in the rear! Yes you will tear your tires off the rim! Yes it will be fun! Yes you are still getting good fuel economy doing it! Haha!
Remember this is a street car, when running a 700R4 slicks are never recommended, and Transbrakes are OUT of the question! Don’t ask! No way! If slicks are not used (AKA you don’t hook worth a **** till 3rd gear) and a T-brake is NOT used, there’s no reason you can’t beat on your car consistently over the next 10 years without so much as a tranny oil change. Now, start hooking up at the track? Things change. Parts go flying. A 700R4’s maximum capacity for horsepower/torque, no matter WHAT ANYONE SAYS, built to the absolute MAX, no holds bar, Sun-Shell or no sun-shell, is roughly 600 Horsepower and 600 Ft. Lbs of torque. Rear end life? Same as above, this is not a ¼ mile setup, it is a street setup. No 10-bolt rear end will stand up to T-brakes and slicks very long. Even the
Rough and rare 9-bolt in top form can only take so many T-brakes. Parts WILL fly.
Now we will discuss tuning issues and longevity issues with our setup.
Our blower comes with a 5-6 PSI pulley, which is fine and dandy for our engine to start with. But remember you can crank up the boost… and the horsepower. The maximum we recommend for street is 10 PSI. Any more than 10 PSI of boost, and fuel octane rating / timing advance / head gasket longevity become serious concerns. At 10 PSI or under we can expect the most and longest life of our small block Chevy.
The biggest killer of our engine will be heat, and consequently detonation. To battle this we need a cooling system up to the task, and a timing profile suited to our boost level and octane rating.
Cooling system:
Nothing less than a Nice 2-Row 1”/1 ¼” Aluminum Radiator will suffice. Griffon sells these for roughly $189 for the 1” and about $289 for the 1 ¼”. (Summit) Is the extra ¼ worth it? If you live in place that’s ALWAYS cold then probably not. But if you like to drive your car in 80*+ weather, then yes. Especially at sea level (here in Florida). The water pump should be anything but stock. Even the pretty cheap summit water pump will suffice. Stewart is the choice of many hot-rodders, and for good reason. The Stewart stage2 water pump is a little pricy, but no one has had a complaint yet. Expect to pay about $150 here. (Stewart) I, myself, used a summit pump (heh). And finally, the cooling ability of the radiator comes back to the fans. Yes fans. Use an electric fan, those flex-fans are out of date. Time to upgrade man. Flex-a-lite sells a nice Dual electric fan setup with a separate water temp control black box thingy that you can set the temp for the fans to come on at. Using your Holley DFI you can subvert control over to the laptop… either way, its still an excellent fan choice. It fits perfectly in a third-gen camaro size radiator, clears the blower snout, and cools with undying efficiency. Expect to pay about $200 for a nice set of these fans, or any other quality electric fan. Avoid the cheap $89 fans; they will break at the worst times.
Now that we have our cooling setup up to the task of cooling our blown Chevy, we need to determine operating temperature. Why is THAT important? Of all things! Well if you want to get the most from your engine… listen up. Keeping the engine cooler (160-170*F) we noticed the best possible fuel economy on the highway, and generally this kept us pretty far from detonation. It also allowed the most room for boost-induced heat-soak, in which the boost for a long period of time (10-14 seconds of 0-140 MPH bursts) soaks into the engine very FAST. At such low temps (160-170) we had a lot more head room for heat buildup. During a typical ¼ mile run, our engine would start at 165*F and end around 200*F. is this normal? As long as it cools off immediately, yes. If it takes long to come down from 200 back to where you set your fans on (165*F in our case) then NO it is a sign of too much boost/not enough free-breathing exhaust. Oh, where did THAT come from? It’s true; a restrictive exhaust will cause your engine to heat up FAST, ESPECIALLY under boost! Very dangerous, this is! In a street environment, where sound should be kept as quiet as possible, it’s important to realize that exhaust restriction plays a major role in keeping a forced induction engine happy. Headers and as big around exhaust as possible should be used. Our motor doesn’t suffer the “lost torque syndrome” of naturally aspirated engines when they use too big of exhaust.
I recommend a mandrel bent, 3”-4” exhaust (when dual exhaust cannot be used) with headers of course, the big ones (1 ¾ primaries) and as un-restrictive a muffler as possible. (Ours is a Delta-flow flow master… not super-load and very un-restrictive. They also offer the American thunder and 40 series both of which are fine.) I would, however, point out that flow master is not the IDEAL Company to purchase mufflers from for a boost platform. A Borla or Raven or Dynomax or even a standard run of the mill “turbo” muffler will produce adequate results.
With that said, we now know about heat, exhaust, water temps, and boost levels. Now let’s go on about TIMING.
Timing is CRITICAL. If you do nothing else, set your timing correctly.
The DFI Holley setup will explain how to make your laptop control timing. I’m not going over that now. What I AM going over is the timing advance LIMITS for safe-street driving.
Base timing should be between 10* and 12* with the cam mentioned above. More timing will be needed if a more radical cam is selected, but note more radical doesn’t mean more power. The blower makes the power, not the cam. Adding more lift/duration will only hurt low end torque and make throttle response more sluggish.
With 10-12 base timing, we want to see a total of 40-45* of timing on the highway during cruise situations. Why so much? Well during cruise when vacuum is highest, there is very little cylinder pressure (compared to WOT that is) and advancing the timing will mean less fuel will be needed to create the same amount of power. Thus, using such huge advance profiles, we get the maximum from our economy point of view. This will also attempt to heat the engine up, so we are back to having the best possible cooling setup.
Now for WOT and boost situations, we want roughly:
No more than 31* of timing during a 5 PSI boost run with 92 Octane fuel and water temp of 180 or less with aluminum heads and 9:1~ compression.
No more than 30* of timing during a 6 PSI boost run with 92 Octane fuel and water temp of 180 or less with aluminum heads and 9:1~ compression.
No more than 29* of timing during a 7 PSI boost run with 92 Octane fuel and water temp of 180 or less with aluminum heads and 9:1~ compression.
No more than 28* of timing during a 8-10 PSI boost run with 92 Octane fuel and water temp of 180 or less with aluminum heads and 9:1~ compression.
Remember your DFI has a knock sensor. Use it. Check it. Record graphs and do endless research on your engine to see what timing profile it LIKES. These are just guidelines to get you started; you have the tools, now do the work. Maximum fuel efficiency awaits.
With the combo above (355, 700R4 (2800 Stall ACT), 10-bolt (3.42), Holley DFI, Weiand 177 etc…)
We made 520 Ft. Lbs of torque and 510 Horsepower, at the flywheel, with 5 PSI of boost.
At the tires? Outstanding 428 torque (13% loss) and 429 Horsepower (14% loss)
With a CRAZY 400~ Ft. Lbs of torque from 1000 RPMS to 4400 RPMS (almost a straight line!)
And an insane 430 horsepower at 5400 RPMS!
I run 92 octane all the time, and a conservative 30* of total timing under 5 PSI of boost. I keep the car at 170* always. My exhaust is flow master mandrel bent American thunder cat-back with cheap hedman shortie headers and their Y-pipe to fit. My hood is stock with a hole cut around the blower and a removable (yes removable!) cowl on top of it (so I can show off the blower whenever). This all sits in a 1989 Camaro RS hard top with the original RS badges, and a stock sounding motor. (Love that cam!) It has the original suspension and a simple addition of sub-frame connectors strengthened the chassis. The rims are 9.5” wide Solid Welds, and house 275/60/R15 tires. And my damn flex plate shield never fit correctly so it rattles and rattles! Argh!! Err... where were we? Oh yeah.
We get (I get) 21-23 MPG (I say 21 and my friend seems to think 23 my dad says it gets 14 MPG but hes always into the boost…) on the street and an outstanding 23-24 MPG on the highway during a 2000 RPM cruise (75~ MPH)
Our ¼ mile time with no traction and a 2.0 60. Ft. time always between 12.56 @ 117 and 12.06 @ 119 and if you think these times are messed up you are RIGHT. Remember, no slicks… no hooking… that’s the key to longevity and fun fun fun! Some people are impressed with tire smoke… others? Horsepower and 1.4 times. I am more impressed with how a car idles, drives, responds, and how efficiently it uses that precious fuel than anything else. Oh yeah, and did I mention how well it shreds the tires? :-D
Recipe for 500 Horsepower, 22 MPG. Long.
Engine Buildup. High performance, Street.
Today’s project: Small block Chevy 355 with a Blower
Target TQ/HP goal: 520TQ/500HP (nice and rounded)
Target Mile per Gallon Goal: 21 MPG (nice and… err... nice)
Target Terrain: Mainly Street, “stoplight racing”, strong 0-60, very strong 0-140 MPH, occasional ¼ at the track.
Target Drivability goal: Mild idle quality, no rough stuff, powerful off the line TQ, excellent response and driving quality, good brakes (heh), and yes we want economy.
Engine block: 1976 (Pre-86) block. .030 Over (355 CID)
Had machine shop Bore, Hone, Clean, Acid Wash, Align BORE and align HONE, then new freeze plugs/cam bearings, and finally, all threads chased and cleaned.
Rotating assembly:
Factory Forged Crankshaft (or aftermarket Forging, 4340 Steel is ideal, Eagle is affordable and recommended.) ours was .010/.010 on the journals to make sure all was perfectly round. Even aftermarket cranks can be egg-shaped or worse, a good 10/10 is recommended to keep things perfect. It is believed that going more than 10/10 is bad on any forced induction motor, I have found this to be incorrect. There is plenty of material left to go 50/50 or further, depending on application. It’s not recommended however, but it’s been done.
TRW Flat tops with D-Cup valve relief (forced induction type) 9.8:1 comp with 68CC head, 8.6:1 comp with 76CC head, and 9:1 comp with 72CC head.
Eagle Forged 4340 5.7” H-Beam rods. 650 Grams each (a little heavy), minor block grinding needed to fit. Used air-grinder to make things simple. Strong, and affordable.
Rings were File fit Federal Moguls, each top and mid rings filed to .28-.30 gap. (Good for forced induction/nitrous. If forced induction/nitrous isn’t to be used, a gap of .25~ is sufficient for the top and .23~ for the bottom.)
Bearing were Clevite 77’s, 10/10 of course to fit journals. A slightly thicker bearing (10/10) is better because there is more bearing to wear before the journals begin to fatigue.
We used ARP bolts on the entire engine, and Studs instead of bolts wherever possible. The crankshaft main caps were no exception. Four-bolt Mains, ARP Studs, with Windage tray provisions. A moroso windage tray was used, but needed to be modified (cut) to fit the stock Oil pan we used. It would hit the rods (H-beams are so big!) so we also… modified… (Ok, we banged it up), to fit…
Total cost of engine so far:
Block ($150 + machine shop labor ($200) = $350 (machine shop had block)
Crank (eagle) = $650 (summit)
Rods (eagle) = $400 (summit)
Pistons (trw) = $320 (summit)
Rings (FM) = $110 (summit)
Bearings (clevite) = $35 (Murray’s)
Studs (Arp) = $65 (summit)
Oil pan (stock) = $100 new (summit)
Oil pump (FM) = $65 with pickup *(summit)
Windage tray (moroso) = $30 (Murray’s)
Shipping for products = $65
Total for Bottom end: $2190
So now we have ourselves a strong, forged, abusable bottom end. Remember, the less we abuse it now, the longer it will last. This engine combo should be good for about 250,000 miles if treated properly, likely more if well maintained. This, in a street environment, is considerable. Our camshaft however, will be flat tappet, thus will likely need replacing sometime around 100K miles, this being the nature of high-life tappet camshafts. Ill explain later….
Now for the most important part, our horsepower making combo, and the reasons behind the economy / power selection.
Comp cams Custom grind
Camshaft: Advertised duration: (or “seat to seat”) 274/286. Advertised Lift: .323/.333, 114 Lobe separation Angle, 5* of ground in advance (109 Lobe centerline)
.050 - .050 duration: 219/228, lift after 1.5 rockers: .484/.500
Power band: 1500-5500 Rpms Vacuum: 15” @ 600 RPMS, 18” @ 800 Rpms
We chose this cam for several reasons… the obvious ones being streetability and idle vacuum/quality. Unobvious reasons? Economy, blower friendly, throttle response. Okay maybe those WERE obvious, no need to rub it in my face. The wide 114 LCA give us boost trapping ability, as well as the ability to trap the most fuel during a highway cruise. The low .050-.050 duration means we get the most of our torque friendly blower, and it also means we get to use our power brakes! Yay! And if you don’t get that, you have never drove a car with a Chevy 350 that had more than 240* of .050-.050 duration on the street.
Now let’s get down to business. No one probably told you this but it’s the heads/cam/intake that makes power. They did? Oh well, but its true. All the forged bottom end parts in the world won’t make your Chevy go any faster. In fact, those 650 gram eagle H-beams only slow it down, they are so big and heavy! But that’s ok, because volumetric efficiency is on our side.
For heads, there are several affordable choices. Our choice was AFR’s 190CC Street heads. A very important thing to realize in a head that will see boost in, is the ability to flow exhaust out. And AFR’s 190CC street heads do that considerably well. Other choices would be brodix track 1’s, Dart 200CC, or even Edelbrocks Performer RPM series. Porting? Unnecessary, but in your best interest if you run at the track a lot. Porting will improve your numbers, but will hurt your street drivability. Things that can’t hurt on the street: 3-angle “street” valve job, Blending of bowl area, exhaust porting, gasket matching (cutting your intake/head gasket ports to the EXACT size of the actual port) and so on… find a reputable machine shop and they can lead you in the right direction.
Head gasket is a Fel-pro steel ringed gasket
Head Studs are ARP and properly torqued down
Now, we have heads and a Cam. What about the intake? Oh yeah, our blower COMES with an intake! How nice! Say, does that make the blower the plenum? Hmm…
Our blower is a Weiand 177 Satin-finish Roots’ style blower.
Total Cost so far:
Camshaft (comp) = $212
Heads (AFR 190) = $1395
Blower (Weiand 177, summit) = $1850
Gaskets / materials (thread sealer, loctite, oil, gaskets etc) = $150
Shipping = $65
Total engine cost so far: priceless (just kidding) $3672 + 2190 = $5862
So let’s say $6000 so far invested into our engine. This is everything bought new, in the box, never touched. You can bring this number down quickly by using used parts and rebuilt parts, but we chose to use everything new simply for longevity reasons.
You can now, if you want to, slap a carburetor on this blower (a 750 vacuum secondary would be nice) and go go go. You would make about 500 horsepower/ 500 Ft. Lbs. yes. But economy? You would get maybe, in a non-overdrive car with a decent gear (3.23-3.42) and proper vacuum advance timing maybe 15-17 MPG. Not bad eh? But where do we come up with the 21 MPG? And what about the extra throttle response / driveability/ street friendly ness? I’m about to show you the wonders of DFI.
Holley Performance sells a complete Kit called the “Commander 950 Throttle Body Fuel injection kit” It comes with everything you need (almost… sigh*) to throw a fuel injection setup on top of your blower. Outstanding throttle response, extra horsepower, and tons more fuel economy and cruiseability can be achieved using this fuel injection setup. You even are required to initially program it using your laptop computer. You control the fuel, and the spark… even under boost you can set the parameters for how much fuel you want to add. I don’t work for Holley, but even if I did, I would still say about the same things I'm saying now. And the price? Ha! That’s the best part. It’s the cheapest fuel injection kit I’ve yet to see, and the easiest to use!
Complete Kit: $1395
Just plug it all up and into your laptop, download a few of the base fuel maps from Holley’s site, and start tuning to your engine’s desire. No more jet changes, no more worry about extra fuel under boost, no more timing light issues, no more detonation concerns, no more blown power valves (thanks Holley!) you can even save different profiles (like one for 87 Octane and one for 93 octane… and even one for 113 octane if you want!) its like a street racers dream come true. Ah... the powers of DFI. And then you can be like “The fast and the furious” with your laptop computer controlling your fuel flow… ah but it works!
Now we have the efficiency of DFI, the power and durability of an all forged/blown Chevy 355, what now? Well now we want MORE ECONOMY and MORE POWER so we look closer at our drive train. What’s this? A TH350 tranny? That has to go. And what else? A 3.73 geared 10 bolt? We will see, yes we will see.
To get the most bangs for our buck (literally) we want overdrive. Yes this means switching to the weaker and not-so-loved 700R4 (or 200R4) but it also means gobs less money spent at the gas stations… We want a BUILT and EFFICIENT transmission, not a stock one. Since our engine makes power RIGHT off idle, stall speeds can be kept very conservative. Since our engine makes GOBS of low end torque, we need a healthy “safe” gear to back it up. Expect to spend about $1300 on a healthy “built to the max” 700R4, and about $650 on a ACT/Yank/vigilante LOCKUP (important)9.5” torque converter. Why lockup and why 9.5”? Well first off LOCKUP will improve your highway MPG considerably, and it will also keep the converter cooler. Why 9.5”? well its been tested and re-tested, but a 9.5” Converter has MUCH higher efficiency at multiplying torque than any 10” or 12” converter, and not to mention LIGHTWEIGHT (can we say “rotating mass is bad”?) the 9.5” just blows away all other converter, and on top of that the lockup “plate” acts as an anti-balloon shield against all that tire shredding torque. You can even spray nitrous and the converter will be the last thing left after everything else went boom. Maybe. But anyways, long story short, 700R4 + 9.5”low stall (2400/2800) converter + lockup = fuel economy! Yes! 21 MPG + can be achieved with this plus the DFI above! Gearing? We don’t need 3.73s to get this baby moving! 3.42’s are the max I would recommend. 3.23s are probably the mainstream for this combo, but for plain street nothing beats a nice set of 3.42’s with that ultra low first gear in the 700R4 (3.06:1) its like having a TH350 with 4.11 in the rear! Yes you will tear your tires off the rim! Yes it will be fun! Yes you are still getting good fuel economy doing it! Haha!
Remember this is a street car, when running a 700R4 slicks are never recommended, and Transbrakes are OUT of the question! Don’t ask! No way! If slicks are not used (AKA you don’t hook worth a **** till 3rd gear) and a T-brake is NOT used, there’s no reason you can’t beat on your car consistently over the next 10 years without so much as a tranny oil change. Now, start hooking up at the track? Things change. Parts go flying. A 700R4’s maximum capacity for horsepower/torque, no matter WHAT ANYONE SAYS, built to the absolute MAX, no holds bar, Sun-Shell or no sun-shell, is roughly 600 Horsepower and 600 Ft. Lbs of torque. Rear end life? Same as above, this is not a ¼ mile setup, it is a street setup. No 10-bolt rear end will stand up to T-brakes and slicks very long. Even the
Rough and rare 9-bolt in top form can only take so many T-brakes. Parts WILL fly.
Now we will discuss tuning issues and longevity issues with our setup.
Our blower comes with a 5-6 PSI pulley, which is fine and dandy for our engine to start with. But remember you can crank up the boost… and the horsepower. The maximum we recommend for street is 10 PSI. Any more than 10 PSI of boost, and fuel octane rating / timing advance / head gasket longevity become serious concerns. At 10 PSI or under we can expect the most and longest life of our small block Chevy.
The biggest killer of our engine will be heat, and consequently detonation. To battle this we need a cooling system up to the task, and a timing profile suited to our boost level and octane rating.
Cooling system:
Nothing less than a Nice 2-Row 1”/1 ¼” Aluminum Radiator will suffice. Griffon sells these for roughly $189 for the 1” and about $289 for the 1 ¼”. (Summit) Is the extra ¼ worth it? If you live in place that’s ALWAYS cold then probably not. But if you like to drive your car in 80*+ weather, then yes. Especially at sea level (here in Florida). The water pump should be anything but stock. Even the pretty cheap summit water pump will suffice. Stewart is the choice of many hot-rodders, and for good reason. The Stewart stage2 water pump is a little pricy, but no one has had a complaint yet. Expect to pay about $150 here. (Stewart) I, myself, used a summit pump (heh). And finally, the cooling ability of the radiator comes back to the fans. Yes fans. Use an electric fan, those flex-fans are out of date. Time to upgrade man. Flex-a-lite sells a nice Dual electric fan setup with a separate water temp control black box thingy that you can set the temp for the fans to come on at. Using your Holley DFI you can subvert control over to the laptop… either way, its still an excellent fan choice. It fits perfectly in a third-gen camaro size radiator, clears the blower snout, and cools with undying efficiency. Expect to pay about $200 for a nice set of these fans, or any other quality electric fan. Avoid the cheap $89 fans; they will break at the worst times.
Now that we have our cooling setup up to the task of cooling our blown Chevy, we need to determine operating temperature. Why is THAT important? Of all things! Well if you want to get the most from your engine… listen up. Keeping the engine cooler (160-170*F) we noticed the best possible fuel economy on the highway, and generally this kept us pretty far from detonation. It also allowed the most room for boost-induced heat-soak, in which the boost for a long period of time (10-14 seconds of 0-140 MPH bursts) soaks into the engine very FAST. At such low temps (160-170) we had a lot more head room for heat buildup. During a typical ¼ mile run, our engine would start at 165*F and end around 200*F. is this normal? As long as it cools off immediately, yes. If it takes long to come down from 200 back to where you set your fans on (165*F in our case) then NO it is a sign of too much boost/not enough free-breathing exhaust. Oh, where did THAT come from? It’s true; a restrictive exhaust will cause your engine to heat up FAST, ESPECIALLY under boost! Very dangerous, this is! In a street environment, where sound should be kept as quiet as possible, it’s important to realize that exhaust restriction plays a major role in keeping a forced induction engine happy. Headers and as big around exhaust as possible should be used. Our motor doesn’t suffer the “lost torque syndrome” of naturally aspirated engines when they use too big of exhaust.
I recommend a mandrel bent, 3”-4” exhaust (when dual exhaust cannot be used) with headers of course, the big ones (1 ¾ primaries) and as un-restrictive a muffler as possible. (Ours is a Delta-flow flow master… not super-load and very un-restrictive. They also offer the American thunder and 40 series both of which are fine.) I would, however, point out that flow master is not the IDEAL Company to purchase mufflers from for a boost platform. A Borla or Raven or Dynomax or even a standard run of the mill “turbo” muffler will produce adequate results.
With that said, we now know about heat, exhaust, water temps, and boost levels. Now let’s go on about TIMING.
Timing is CRITICAL. If you do nothing else, set your timing correctly.
The DFI Holley setup will explain how to make your laptop control timing. I’m not going over that now. What I AM going over is the timing advance LIMITS for safe-street driving.
Base timing should be between 10* and 12* with the cam mentioned above. More timing will be needed if a more radical cam is selected, but note more radical doesn’t mean more power. The blower makes the power, not the cam. Adding more lift/duration will only hurt low end torque and make throttle response more sluggish.
With 10-12 base timing, we want to see a total of 40-45* of timing on the highway during cruise situations. Why so much? Well during cruise when vacuum is highest, there is very little cylinder pressure (compared to WOT that is) and advancing the timing will mean less fuel will be needed to create the same amount of power. Thus, using such huge advance profiles, we get the maximum from our economy point of view. This will also attempt to heat the engine up, so we are back to having the best possible cooling setup.
Now for WOT and boost situations, we want roughly:
No more than 31* of timing during a 5 PSI boost run with 92 Octane fuel and water temp of 180 or less with aluminum heads and 9:1~ compression.
No more than 30* of timing during a 6 PSI boost run with 92 Octane fuel and water temp of 180 or less with aluminum heads and 9:1~ compression.
No more than 29* of timing during a 7 PSI boost run with 92 Octane fuel and water temp of 180 or less with aluminum heads and 9:1~ compression.
No more than 28* of timing during a 8-10 PSI boost run with 92 Octane fuel and water temp of 180 or less with aluminum heads and 9:1~ compression.
Remember your DFI has a knock sensor. Use it. Check it. Record graphs and do endless research on your engine to see what timing profile it LIKES. These are just guidelines to get you started; you have the tools, now do the work. Maximum fuel efficiency awaits.
With the combo above (355, 700R4 (2800 Stall ACT), 10-bolt (3.42), Holley DFI, Weiand 177 etc…)
We made 520 Ft. Lbs of torque and 510 Horsepower, at the flywheel, with 5 PSI of boost.
At the tires? Outstanding 428 torque (13% loss) and 429 Horsepower (14% loss)
With a CRAZY 400~ Ft. Lbs of torque from 1000 RPMS to 4400 RPMS (almost a straight line!)
And an insane 430 horsepower at 5400 RPMS!
I run 92 octane all the time, and a conservative 30* of total timing under 5 PSI of boost. I keep the car at 170* always. My exhaust is flow master mandrel bent American thunder cat-back with cheap hedman shortie headers and their Y-pipe to fit. My hood is stock with a hole cut around the blower and a removable (yes removable!) cowl on top of it (so I can show off the blower whenever). This all sits in a 1989 Camaro RS hard top with the original RS badges, and a stock sounding motor. (Love that cam!) It has the original suspension and a simple addition of sub-frame connectors strengthened the chassis. The rims are 9.5” wide Solid Welds, and house 275/60/R15 tires. And my damn flex plate shield never fit correctly so it rattles and rattles! Argh!! Err... where were we? Oh yeah.
We get (I get) 21-23 MPG (I say 21 and my friend seems to think 23 my dad says it gets 14 MPG but hes always into the boost…) on the street and an outstanding 23-24 MPG on the highway during a 2000 RPM cruise (75~ MPH)
Our ¼ mile time with no traction and a 2.0 60. Ft. time always between 12.56 @ 117 and 12.06 @ 119 and if you think these times are messed up you are RIGHT. Remember, no slicks… no hooking… that’s the key to longevity and fun fun fun! Some people are impressed with tire smoke… others? Horsepower and 1.4 times. I am more impressed with how a car idles, drives, responds, and how efficiently it uses that precious fuel than anything else. Oh yeah, and did I mention how well it shreds the tires? :-D