Thread: Need help with some high mod SBC questions

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So Im sick of my heavy camaro being a turd with a mismatched motor, laggy gears and rich running conditions in this ridiculously unstable Virginia weather.
So, Im ripping out the whole drivetrain, installing my 3.73 gears, building the 700r4 and Im either gonna go with a 350 with an lt4 hotcam and a decent set of reworked heads for a good deal, or Im gonna go all out and go 383 with a set of AFR 210 heads on 10.5:1, 2.08 intake valves, .564/.570 lift, 274/280 roller cam with 110 lobe separation although Im looking to find a replacement cam that's got a 112 LSA to make it more drivable, reuse the MSD system I have now, long tube headers (probably 1-5/8 but if I can afford it, 1-3/4) with a full 3 inch exhaust system from the headers, single plane intake, balanced, with a fuel injection system to keep it stable for street driving and consistent performance.

1) I have a few questions for you guys. What kind of HP numbers would you say a setup like this would run? I have had this setup in desktop dyno for a couple of years and I know what that program says it will do but I dont know if that's realistic. I put in 3 edelbrock crate engine before and the numbers came out of the program accurate to 5 percent, and I think that's pretty impressive.

2) are 210 heads too big for this application? Im looking to peak HP at 6000, maybe 6500 and with the lift on this cam and the intake valve size of the heads, am I gonna shift before I really get the best out of this motor? DD shows peak hp with this setup being 6000 on the dot, with only a 2hp drop to 6500rpms.

3) The cam listed is a mechanical roller, but I do NOT want a mechanical street car. would it be possible to either just slap hydraulic lifters on this cam, or maybe have one made custom to allow for hydraulic lifters? I really dont know what the difference is in a real world build.

4) I want either a 900cfm 4 bbl holley injection system, or if I can piece one together I'd like to buy a tpi system, sell the intake and injectors, buy a stealthram intake/fuel rail and some nice injectors and build a MPFI combination for this. what would be needed to do such a thing, and would the stock ECU at all be able to be tuned to handle this or would I need an aftermarket ECU, or would it just be better to buy an aftermarket harness/ecu system and then piece all the hardware and sensors together for the MPFI system?

sorry for the long post and so many questions, but Im getting to a point where all of these things I've been thinking about for a while are finally gonna be coming together and I'd like to know what I need to expect to complete this build properly the first time

3)

1) I have a few questions for you guys. What kind of HP numbers would you say a setup like this would run? I have had this setup in desktop dyno for a couple of years and I know what that program says it will do but I dont know if that's realistic. I put in 3 edelbrock crate engine before and the numbers came out of the program accurate to 5 percent, and I think that's pretty impressive.

**I found DD to be within 5 per cent with my 383 build. I think that is a reasonable assumption.

2) are 210 heads too big for this application? Im looking to peak HP at 6000, maybe 6500 and with the lift on this cam and the intake valve size of the heads, am I gonna shift before I really get the best out of this motor? DD shows peak hp with this setup being 6000 on the dot, with only a 2hp drop to 6500rpms.

**I would use their 195 Eliminator heads. Unless you are turning a lot of rpm, you don't need 210's, especially for a street driven car. You will lose low end torque with 210's. AFR's 195 Eliminators make awesome hp and torque.

3) The cam listed is a mechanical roller, but I do NOT want a mechanical street car. would it be possible to either just slap hydraulic lifters on this cam, or maybe have one made custom to allow for hydraulic lifters? I really dont know what the difference is in a real world build.

**Solid rollers are not meant for the street. And you cannot mix and match lifter types with cam types. I would go with a hydraulic roller cam instead. You do not have to have a special cam grind made. There are a lot of choices out there from numerous companies. For street friendliness, I would recommend staying between 230 and 235 degrees of duration.

4) I want either a 900cfm 4 bbl holley injection system, or if I can piece one together I'd like to buy a tpi system, sell the intake and injectors, buy a stealthram intake/fuel rail and some nice injectors and build a MPFI combination for this. what would be needed to do such a thing, and would the stock ECU at all be able to be tuned to handle this or would I need an aftermarket ECU, or would it just be better to buy an aftermarket harness/ecu system and then piece all the hardware and sensors together for the MPFI system?

**A TPI will not handle the air needed for a 383 to breathe. Both Edelbrock and Holley sell similar injection systems. But there is a new kid on the block that I am very interested in. I would seriously consider this: www.fuelairspark.com/ezefi/default.asp

sorry for the long post and so many questions, but Im getting to a point where all of these things I've been thinking about for a while are finally gonna be coming together and I'd like to know what I need to expect to complete this build properly the first time.

Hey Camaro, do a search of posts that are under my user name and click on the one titled desktop dyno help. You will see the engine I built and the results achieved using a set of the AFR 195s.

http://www.clubhotrod.com/forums/sho...t=desktop+dyno