I want to put some heads on my stock tpi, will i have adverse effects with a stock chip, and computer ? What are the best heads out there in your opinions for a stock motor ? Actually i want to get heads and a camshaft, what is a good combination ? and how hard is it to install heads ?

 

Heads alone wont affect the computer at all.

Before I (or anyone else) can answer what to get, I have to know what you want to get out of the car.

 

not to argue with Madmax....but speed density cars are very sensitive to changes and if you want to get your car to run correctly with a new mod, it is most likely that you will need a reprogramed PROM. this is assuming that you have a 91, just going off your screen name. More info about your car is needed to make a good recomendation here.

as for a good set of heads, Dart is the way to go. Dart Iron Eagles are great flowing heads and you will see a really good boost in HP. good luck man.

 

HAHA! Heads will make a BIG difference in how your car idles, drives, etc... Different heads need different advance curves and have different fuel requirements.

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92 Z28 5.7
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Trick Flow 23° heads, Comp Cams XR270HR-10 cam, Accel intake base + ported TPI,
TES headers, Flowmaster catback, MSD ignition, #24 SVO injectors, 1LE aluminum driveshaft.

Click here to see pics of my car !

 

How is that guys?

The cam, intake, and exhaust have much more control over the airflow of a TPI car than the heads do.

I wont even go into the SD thing, Ill let Kevin do that.

 

I think he should know, he has heads and other stuff on an SD setup.

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89 RS

Looking For:
87 IROC-Z28 350 TPI

 

Yea he has cam, intake, exhaust, injectors...

Still doesnt address my original post, that heads ALONE wont affect it. If the air is being limited by something other than the heads (it is) no more air is going to flow in and therefore it makes no difference. The only thing that will happen with putting, say, AFR 210's or the like on there is the fuel separation and velocity will go to hell, and it will run like crap.

 

I believe it will have a lot to do which part is the "weak link" that is limiting flow. At lower rpms, a good set of heads will have an affect as they will offer greater flow at lower lift and tend to be the biggest bottle neck. But at higher rpms, the cam and intake will become the limiting factor.

The nice thing is that at lower rpms, you are generally in part throttle and the O2 sensor will be operating in closed loop. So the ecm will be compensating. But at WOT, you will be in the higher rpms and though heads may help, the intake and cam will still be holding you back.

But, another good thing is that the stock SD eprom tends to be overly rich as is, so you actually may be getting closer to a better AF ratio.

Just wait until you add the remaining items (intake and cam), now you'll REALLY feel them. Unfortunately, the TPI's intake/cam/heads are are pretty close to matching the same low flow values, as Madmax is suggesting.