Cylinder Heads

[JoeliusZ28]

Joel believes in the mystical powers of the opti-spark, just... leave him be.

i could believe in TPI i suppose

[JoeliusZ28]

Okay, so let me get this straight.......more weight, less HP and still runs the same times

I am strictly talking dyno numbers, not actual power.

Several people have dyno-tuned their car for max dyno horsepower, and run say 110mph... only to track-tune the car and run 112, but then record less power on the dyno. It is likely the same "dyno queen" phenomenon.

[Formula Z]

yes we need a track day!

[MattODoom]

i could believe in TPI i suppose

You could but, you don't own a TPI so why would you?

Even real TPI guys know their shits weak. We love TPIs because TPIs are sexy, not because we refuse to embrace new technology.

[JoeliusZ28]

what im trying to say is nothing to do with LS1s or LT1s or TPIs being "better" than another. if there is a power to performance difference as i suspsect, that doesnt really mean anything in that sense.

[MattODoom]

what im trying to say is nothing to do with LS1s or LT1s or TPIs being "better" than another. if there is a power to performance difference as i suspsect, that doesnt really mean anything in that sense.

Well, I have a perfectly mint ALL stock LS1 ride to compare it against. Your car is not stock by any means.

[JoeliusZ28]

Well, I have a perfectly mint ALL stock LS1 ride to compare it against. Your car is not stock by any means.

im not debating LT1 vs LS1. if you want to do that we can do it in another thread, this one is about cylinder heads and how much power you need for 12s (with an LT1).

frankly the LT1 vs LS1 horse is beat bad enough.

[badinfluence]

I think I'm going to attempt to port them myself. I'll pick up the tools shortly, hopefully find some old alum. intakes of maybe something like a 2.8MPFI to practice on.

At the very worst it will be a learning experience, but everyone has to start somewhere.

[JoeliusZ28]

I think I'm going to attempt to port them myself. I'll pick up the tools shortly, hopefully find some old alum. intakes of maybe something like a 2.8MPFI to practice on.

At the very worst it will be a learning experience, but everyone has to start somewhere.

Im looking into home porting as well. check out Vizard makes a good book for porting small block chevy heads you can pick up at the book store for about $15.

[badinfluence]

Thanks for the tip.

I'm going to try and find some cheap aluminum 2.8 heads and intake just to play around with first.

As far as the porting process goes, how different are prelt1-sbc heads from LT1 heads? I've found alot of guides for general sbc heads, so far no specifcally for LT1

[badinfluence]

I'm looking for parts to slowly start gathering.

Can anyone suggest some good parts that will work well together w/ ported heads. I want a large, yet daily-driveable cam, ride comfort isn't an issue, i dont care if the car bounces around but it needs to be pretty reliable.

I was thinkin cc503?
cc pushrods & lifters
rocker arms, are stock sufficient? I dont see why aftermarket would help that much if its the same ratio
timing chain, is an aftermarket one a good investement?

[JoeliusZ28]

Thanks for the tip.

I'm going to try and find some cheap aluminum 2.8 heads and intake just to play around with first.

As far as the porting process goes, how different are prelt1-sbc heads from LT1 heads? I've found alot of guides for general sbc heads, so far no specifcally for LT1

yes they can be very different. Some of the early 80s heads seemed as though they were designed to be restrictive.

I'm looking for parts to slowly start gathering.

Can anyone suggest some good parts that will work well together w/ ported heads. I want a large, yet daily-driveable cam, ride comfort isn't an issue, i dont care if the car bounces around but it needs to be pretty reliable.

I was thinkin cc503?
cc pushrods & lifters
rocker arms, are stock sufficient? I dont see why aftermarket would help that much if its the same ratio
timing chain, is an aftermarket one a good investement?

didnt you say your car was cammed already? CC503 is a good choice for an LT1 driver. You can get them in different LSAs which will affect how driveable the car is: 114, 112, and 110. (LSA affects overlap). 112 is the standard grind, 114 is the friendly one and 110 is wilder. Im putting a 110 grind 503 in my car this spring. a 112 will have some decent lope to it, and a 114 will almost sound stock.

Also do not use Comp 918 springs, they have a breaking problem lately.

[WMCCjames]

I would stay away from home porting unless you have many hours porting experience on other aluminum pieces...ie, intakes. Porting cast iron and porting aluminum is alot different. For instance, I have a couple aluminum burrs that can cut through the material so quick it's decieving. In the hands of someone who is a novice this could spell disater quite quickly. You break into the water jacket and your screwed, unless you take it and have it tig welded somewhere. Also you need to be sure and get all the ports shape and volume very close to the same on EVERY one.....very hard to do without a flowbench.

[badinfluence]

I was thinking about this at work today. I'll get some sound clips up of the car to show you what I'm going on.

I was thinking about just port/polish heads/intake, rocker arms/springs while there off and leaving the cam alone

would aftermarket arms & springs make a difference worth the price ~300-400

what about comp pushrods? (only 40 bucks)

and can you change lifters without doing a cam swap?

I