Ok first of all the parts i have listed are what i have laying around in the garage. Im looking to put a decent combo together a cheap as possible and im hoping you guys can help me troubleshoot any issues (or suggest something better) before i get too far into this. The car will be driven on the weekends as a toy w/ occasional track time. Mostly i want to be able to "burn the cool off a corvette" at a red light.

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My parts list as of now:

2000 5.7 vortec shortblock w/ around 60k miles - stock rotating assembly. No ridging on the cylinder walls so im hoping i can get away with a re-ring and new bearings.

062 vortec heads w/ low miles - completely stock

Edelbrock RPM Air-Gap intake for vortec heads

750cfm edelbrock carb

Accel HEI distributor w/ billet aluminum housing

1.6 aluminum roller rockers

NOS carb plate nitrous system (adjustable 100/125/150)

Headman Long Tube Headers w/ cherry bomb race mufflers.

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My issue at this point has been cam selection. I have what i believe to be a stock LT1 cam that came in the block when i bought it. I also have an opportunity to get a great deal on this cam and lifters http://www.compcams.com/Cam_Specs/Ca...x?csid=96&sb=2 but im not sure if i would be happy with it as it falls off pretty sharply after 5k rpms. I know its a 4x4 grind but like i said its a great deal.

Im not opposed to buying a new cam because i have almost nothing in the rest of the parts but if one of these 2 cams would work well, would you use it?

My car is an 86 IROC w/ a T5 and a rediculously high rear gear (i think 2.73 but i cant find the markings on the housing so im not positive). The car weighs right at 3000lbs without me in it. It has a 6 point roll cage installed and sub-frame connectors coming soon. Stock 16 inch IROC wheels with 255/50 R16 on the rears.

 

I'd avoid an air-gap manifold on a street engine. Fuel + manifold vacuum = wicked cold evaporative cooling. On a race car that spends the majority of its time at full throttle they're great, but street engines don't.

Other than that, just mind the 5500 rpm redline in your cam choice (ie don't cam the crap out of it when you can't spin it to where it'll make power). Unless you want to go for aftermarket rods and rebalance the rotating assembly. But honestly, is there a reason you're going to rebuilt the shortblock? 60K isn't much, why not just throw some clean, synthetic oil in it and rock-n-roll.

Also, what's your plan for the drivetrain?

 

i would stay with a roller camshaft. http://www.summitracing.com/parts/CCA-08-500-8/ everything else looks good

 

Evaporative cooling - can you elaborate on this please? I had an 80 trans-am with a 400 and those engine came stock with a manifold very similar to the air gap design from edelbrock. That engine always ran well under any condition. Is there a difference in the 2 that im not seeing?

Cam Choice - is the Comp Cam grind i listed above a decent one for a street/strip car in your opinion? How much extra lift do 1.6 rockers give me over the advertised lift? Do the rockers require machining the heads for screw in studs and better valve springs?

Short Block - Im going to at least re-ring and bearing the block just to be sure. I bought it off a member on these boards but i still want the reassurance a cheap rebuild will give me.

Drivetrain - Im up in the air on this one. I like the stick but i know the T5 wont last long so im debating on selling it and finding a T56 but the 16 year old in my head tells me to just put the mototr in and replace the trans when it grenades . As for rear end ill have to see what kind of power i end up with, my old camaro has 373's and they were nice but made 1st gear almost useless unless you wanted to spin the tires. It always launched better in second and feather the clutch in. With the 273's 1st gear is much more usable but i do miss the punch the rest of the gears had.

Thanks for helping me brainstorm, i appreciate the input.

 

Is that price for just the cam? I like the idea of a roller cam but the prices are so much higher than non-rollers. Given the predicted power potential of this combination, how much extra power would the roller cam give over non-roller?

 

you can have your stock cam reground for around 150 or find a good used one. a roller cam is worth 30hp with better driveability.

 

I don't know anything about the pontiac 400, so I can't comment. But the manifold can get icy cool, which isn't exactly good when you want to suspend a fuel charge in it.


I second the roller cam opinion. The technology is simply better in every way. If you want to know the lift with 1.6 rockers, just multiply the lobe lift by 1.5. If you only know the valve lift, divide by 1.5 and then multiply by 1.6. As for what cam to run, personally, I wouldn't get too hung up on what lift to run.

 

Thanks for the replies

Ill have to do some thinking ont he cam..... the grind i listed above i can get for $65 w/ lifters and pushrods..... or $400+ for a more aggressive roller cam..... decisions, decisions....

 

The difference is the exhaust crossover. Your 400 probably had that. When the engine is cold, exhaust gets run through the crossover, which is directly under the plenum. This heats the plenum faster than just bringing it up to temp by itself. It's how the factory got fuel to atomize during cold starts (welcome to emissions era). Air Gap manifolds lack this nifty feature. So no assistance from the exhaust in the fuel atomization department.

If it will be driven in the spring and fall times, when the weather can dip into the 40's, get a regular RPM instead of the Air Gap. The 'been there, done that' part me hated the sluggish warm up times (Had an Air Gap on a 383 for a while, was a PITA on those brisk Michigan mornings/nights). Of course, if it's a warm summer day-only type of car, then go ahead with the Air Gap.

I also agree with all that is said about the roller cam. Be careful to watch lift figures when purchasing, though. Unless you have plans to have the guide bosses on the heads milled down (not a bad idea).