So I am looking for some advice. I bought my car because it was from nevada, and last week I replaced all my carpet and found ZERO traces of rust ANYWHERE. So that was a pleasant surprise. I was having a hard time routing my vacuum lines so I looked here and found my valve covers had put put on incorrectly. Swapped side from side, while I had them off I took the time to find the casting numbers and write them down. After A LOT of searching i found that the heads are 350 heads made in 1991. I was pretty happy till I searched on the good ol' TGO and found that they are most likely off a TBI truck. Crud to say the least. Casting number 10110810 IIRC, so what are my options now?

Well, really the question do these heads have any potential at all? from what i read not really. And I am running a tpi intake with the edelbrock lower intake, so how much power am i really putting down? my guess would be about 210hp, and thats at the crank.

 

They're trash. No big deal.

So, replace em.

Not to complex. Really.

Who cares what you're putting down NOW? You know what you've got, you know what you've got to do, you've got a good car to do it to... go for it.

 

So what is the question really? I mean if your happy with the way the car runs what difference does it make what heads are on the car or HP? On the other hand if you had some goal the car as is was failing to meet I think we would be able to give better advice as to what would work.

 

Agreed. And true as sofa said you could bolt a set of better heads and off you go but, since the heads were a mystery to you then I'm guessing so is the rest of the motor. Cam, pistons, etc are unknown. How do you properly pick a set of heads without knowing what the rest of the engine is or have a performance goal in mind?

 

The tbi swirl port heads are actually not that bad, unless you're trying to get at 400 hp or something. Remember heads are only part of a motor, a big part but still not everything. The swirlies produce alot of torque and can be ported pretty well. Pair em with a good cam, intake, and exhaust and you'll have a pretty fast street car. I'm not saying they are the best heads but they do have a purpose, torque, which moves us

 

No, they're really not...

They're WORSE.

Ignore all that, especially the part about "porting". They are arguably the most resistant to any use resembling "performance" of any head ever made by GM.

Even the performance limitations imposed by TPI are not as restrictive as those heads. While TPI all by itself will prevent an engine from ever making any serious power, those heads will prevent even TPI from reaching its full potential. Hard to believe I know, but true just the same.

Throw em in the trash and move on. Don't waste your life on pointlessly messing with em.

 

That is the big problem, I really do not know anything about the motor. I took it for a drive to get groceries and some fresh gas. First time I have driven it in close to a year. Apart from spinning the passenger rear tire () the power felt alot like the 3.8l v6 in my impala. Crud.

I guess what I will end up doing is just keep playing with this motor, get into tuning and just use it to learn. Install the NO2 i have and go. At least we wont ruin anything of much value. While I build a 355 to be installed later in the fall. The last time I got to enjoy the car for a full season was two years ago.

 

Yea, I probabally should also say that when I bought it, he told me the motor had been swapped to a 350, and that it had a cam (roughish idle) so the motor is a complete mystery. So I was happy to see that the heads were leaning towards the car actually having a 350 in it.

A buddy of mine has a set of Vortec heads he would sell to me for $200. So now im just going to build a backup 355 or 383 for the fall when I pull the boat anchor out

 

Bingo!
Exactly what I did for my daughter's car (see sig). She's had a blast with it for a few years with no more than $250 worth of performance parts since we bought it.

 

I'm sure he needs a 10 second street car, but some people would disagree.