I've got a couple questions. I have a 350 TPI MAF motor that i am rebuilding. It has the TPIS torque secrets cam in it now. Here is the specs:
Intake Exhaust
Advertised duration 276 286
Duration at .050 221 230
Gross lift .454 .454
Lobe separation 112

Now, i also have a set of 76cc heads that have been machined for 2.02 x 1.60. The have been extensivly ported. (I'm talking many hours) Have all the other goodies installed also. I picked the heads up off a coworker a couple years back. Would these heads work on this motor?? The car is an 85 vette. Motor was in the process of being rebuilt. Then the project got dropped. I'm putting it back together and trying to figure out how I want to go about it. I really don't want to put it back to stock.. not while I can have it down and the intake is off and all.

How would you all go about this??
I know this i a thirdgen board but its the same motor and theres some good knowledge on here.
I am not going to spend a great deal on money on performance parts. 1k heads are out of the question.
Vortec's and another cam are possiblities though..
What do you all think???

Thanks!

Arcaidy

 

You would loose alot of compression with those heads, not only that but the way you describe them I'm assuming they are GM heads, In which case even "Extensivly porting" doesn't put them up as contenders with aftermarket heads. I dont think thats the direction you want to go unless your engine already has unusually high compression.


By the way welcome aboard

 

Thanks for the info. I'll skip the heads. The stock heads are gone. I've priced heads at autozone for $ 300 a pair. Would that be a good idea? The car has a rebuilt stock bottom. I have some money to play with, but the wife won't put up with to much..









What about the cam?? should it stay or go. I haven't been able to find any first hand info on the cam. Just whats on TPIS's website.











Anyone??



Thanks!



Arcaidy

 

The cam sounds great except it lacks in lift.

I'd recommend some Vette L98 heads if you can find them, they work great and sometimes can be found for around $500.


Or you can go vortec but that means a new base.

 

The intake alone sells for $400. Add in the cost of the Vortec's and your pushing $1k. Is this really worth it? I want to stay with the TPI. I drove a TPI vette a few years ago. From stop light to stop light it was awsome. I had a 99 T/A that couldn't compare the that. Top end was a different story....

Are the vortec's that much better? Are they worth the price. Granted, I shoudl go with something other than the stock iron's. But seems with the intake the vortec's cost near as much or more than other aftermarket heads.


Thank again for your input

 

The vortecs produce some insane torque, and the new base you buy gives you the option of porting the snot out of it compaired to a stock base, but for $1k you gotta answer if its worth it to you or not. You can probably see very very low 13's on vortecs, but the Alum L98's mean the same base, still great torque, they port better, and they're lighter.


I like the aluminum L98's personally


If you start talking aftermarket then its a different storry

I bought my sportsman II's for less than what it would cost to run vortecs, and compairable to what it costs for alum L98's

 

Vortecs= $480 pr.
Vortec TPI intake= $399
Total= $879

Sportsman IIs= $795pr and you can port the **** out of the stock intake.


JMO


John K

 

I can't remember which post it was but I remember somebody was getting some impressive numbers out of porting the stock heads and intake. He posted some flowcharts that showed improvements matching some aftermarket heads(I BELIEVE). I will search for that post so you can see the results and let you know.

 

do a search on l98 head project a bunch of interesting reading and alot of flowchart research I am begging this project tomorrow!

 

I have been informed that the block has 9:1 compression with these heads so I don't really need anything any higher than that. I have the heads and all the need is a valve job. I am not an engine expert but i think these will work good. They have 2.02/1.60 , screw in studs and lots of porting. They mimic whats found in "how to hotrod small-block Chevy's". I used their template. I have also gasket matched them.
I also like the idea of using the stock base and all. I'd like to see what I can get out of it. Maybe I am being foolish?? I have hogged out the stock manifolds (this is a vette) They should beath alot better now.
I've been doing searches on most of this stuff. I think i will do the porting on the stock base. Looks like some good results have been seen doing this.

Thanks for all of your replys!

Arcaidy