Hey Y'all


I was wondering if these heads
10239906
which code up as Vortec 5700 heads with;
170 intake port
64cc chamber
194/1.5 valves

Would be a good set to put on a 90 Chevy with the TBI ?

What are a set of these worth?




Thanks


Rob

__________________
"SlowRide66"

"Illegitimis non carborundum"
Don't let the bastards grind you down!

Im pretty sure you know that you will have to run a special manafold for vortechs. you can get one from edelbrock for around $250-300. they are very steep. the heads would be a great selection for a tbi engine because they have exceptional flow rates at low lifts, and they flow at a high velocity which helps with atomization and packing the cylinders at low RPM. the only real problem is that you will have to do some modifications to the pcm to be able to get the best out of these heads. these heads flow more air into the engine and you have to be able to send more fuel with the extra air. Im no master mind when it comes to calibrating fuel injection. the pcm might compensate just enough that you dont have a lean mixture but with a speed density system you can only do so much before you have to change peramaters in the pcm. there are places online that you can go to that will burn you a chip with your specific engine combo. hope this helps.

I agree with what`s been said but I will also add you`ll have to plumb a custom EGR from the exhaust manifold or have EGR eliminated via a chip since the vortecs do not have a exhaust heat riser passage. The TBI system isn`t the hot tip, but if I already had it I`d keep it before switching to a carb. I would find someone who can sit and your vehicle and plug in to find what the engine likes, playing guessing games with chips is a waste of time and money, while a real good chip burner can usually come close, most home brew chip burners don`t even get within the ball park. While having someone do it direct to vehicle costs more, it`s worth it. I have a modified chevy 4.3 V6 in my pickup, and I left the chip stock until I can get someone to make a chip after scanning the computer, To make up for the extra flow, I just raised the fuel pressure.

Thanks for the reply's

This is for a buddy so me with my limeted knowledge got a good understanding of it all after discussing this with him .

So his thought was would there be a advantage to putting a Big Block Prom or ECM to do the job?



R

__________________
"SlowRide66"

"Illegitimis non carborundum"
Don't let the bastards grind you down!

They will be a GREAT improvement. The vortecs are the best-flowing factory iron head ever, and the TBI heads are one of the worst.