'88 TBI Build

[Powerhouse Ranch]

https://harristuning.com/Tbi/recommended-350-tbi-mods/ ?

 

[Ricko1966]

current original heads are warped due to idiot PO

Okay, what number are they? And do they have a fresh valve job?Depending on what you have they may be a candidate for a resurface. If money isn't a problem he ll yea get some good heads.

 

[Catbox]

Keep in mind that the stock TBI heads are a swirlport design and flow DIES at 4,000 rpm.
My suburban came from the factory with them and they will not rev past that point.
I have read that they are the worst flowing heads that Mother GM has ever produced.

If it were mine, I would not use a stock TBI head.

Here is a good place for some information on the AFR Eliminators:

AFR ENFORCER 200cc HEADS CHEVY 350 383 65cc STRAIGHT PLUG 272-AFR | Skip White Performance - We have the best prices you will ever find for aluminum heads, rotating assemblies and strokers

AFR Enforcer 200cc/65cc ULTRA HIGH FLOW CYLINDER HEADS STRAIGHT PLUG, FOR SBC CHEVY 327, 350 & 383 ENGINES. Setup for hydraulic flat tappet cams. Not for use with roller cams. 200cc, (Actual size) RUNNERS, 65cc COMBUSTION CHAMBERS. ARP studs, 3/8's or 7/16's, (your choice) and AFR 2pc...

www.skipwhiteperformance.com

They may have too much intake runner for a low RPM truck that just lumps around.

Perhaps @Rusty Nail will have some stock head info to share as I know he loves to find them on the interwebs and hoard them.

 

[gmbellew]

the stock heads aren't good for much past 4500rpm or so. they arent designed to be high RPM heads, built for low end torque and fuel economy.

I'd look at tbichips.com Plum Crazy Purple project for an example of about the best you can do with stock heads and an accompanying tuned PROM chip.

 

[AyWoSch Motors]

and @AyWoSch Motors

the main point of it is that's really causing this all, as stated in my last post, my current original heads are warped. The PO "rebuilt" the motor, had the short block sent out and it's damn good. Then he put the rest together: egr ports were clogged solid, NEW head gasket has massive leak between 3 and 5 with idle time on motor. It's clear he had no idea what he was doing. Didn't think to clean anything, guarantee he doesn't know his torque sequences. HE HAD THE EXAUST MANIFOLD RTV'd ON! Anyway I don't know why it was rebuilt but the head is definitely screwed. Perhaps he ran it on blown head gasket I DON'T KNOW.

But the MAIN thing here is i need heads now, bottom line. I wanted to do bare minimum, but the bottom end was brand new and now i need heads. That just opened the door for some upgrades and i was looking for the most reasonable, noticeable, simple upgrades while i'm here.

SO, TBI will stay and be damn near stock. Still leaving the heads question. I'm assuming AFR now, 99% of you guys are against Vortec, which a week ago was the next best thing in my book. Then again, no one knows these trucks like we do. Which i why i asked you guys.

Well id say, since you need heads, and if your good with spending the money, by all means, get the nice AFR heads. Do a slightly heavier cam, headers and a nice intake. Thatd make it pretty darn nice.

My suggestion would be, whatever intake you get, get a standard 55-86 bolt pattern square bore 4bbl and a 4bbl to TBI adpater.
That way you can run your tbi, and see how it does, and when you get tired of it, or you want more power, or it starts having issues, swaping to somthing else will be easy, instead of having swap intakes too.
You then have the option of a variety of carburetors or aftermarket EFI to swap too someday down the road if/when you change your mind about the "fuel makeithappener".

Thats the best sugsstion i could think of putting out there. Set yourself up for a backup plan instead of screwing yourself later.

 

[bucket]

I've been on the road a bunch and haven't been able to pop in here much lately. Boy this thread sure took a turn in the discussion, lol. All I can say is, of course AFR heads of any kind are going to flow and perform better than stock vortec heads. If aftermarket aluminum heads can be in the budget, by all means go for it... but I'm betting many of them don't have heat crossover ports so watch out for that or we may be right back where we started.

But anyway, while I was driving and nothing better to do than think about stuff, perhaps we have been comparing apples to oranges with the whole heat crossover deal. You fellas that have had the bigger issues have been running a TBI type electronic injection. Perhaps the fuel puddling simply wreaks havoc with the fueling and the ECM can't decide what to do fast enough? Where as a carb just does it's thing based on the requirements for airflow. If there's fuel puddling, it just gets mixed inconsistently with the air moving past it and that's that. There's no O2 sensor telling the carb what to do.

 

[Powerhouse Ranch]

Well id say, since you need heads, and if your good with spending the money, by all means, get the nice AFR heads. Do a slightly heavier cam, headers and a nice intake. Thatd make it pretty darn nice.

My suggestion would be, whatever intake you get, get a standard 55-86 bolt pattern square bore 4bbl and a 4bbl to TBI adpater.
That way you can run your tbi, and see how it does, and when you get tired of it, or you want more power, or it starts having issues, swaping to somthing else will be easy, instead of having swap intakes too.
You then have the option of a variety of carburetors or aftermarket EFI to swap too someday down the road if/when you change your mind about the "fuel makeithappener".

Thats the best sugsstion i could think of putting out there. Set yourself up for a backup plan instead of screwing yourself later.

all i heard was "fuel makeithappener" haha.

That is a good suggestion. You can tell it's a good one, because of the way that it is. . .

 

[Rusty Nail]

Thanks Catbox.
It's true what he said. Swirl ports are not conducive to "high performance", they have a "ramp" on the intake side and is built to slow the port flow I guess haha.
And I have been known to  hide sets of cool SBC heads...*coff coff*

LoL. I consider World Products Torquer heads a good deal and built some for a 406. Drilled the steam holes and everything!
Soon enough y'all can watch me swap the #193s on my Blazer for # 803s. There is also aluminum #113s that flow pretty well and can be sourced inexpensively...I  may be  hiding some of those for a Z28, in addition.

 

[Ricko1966]

083s?

 

[SquareRoot]

I've been on the road a bunch and haven't been able to pop in here much lately. Boy this thread sure took a turn in the discussion, lol. All I can say is, of course AFR heads of any kind are going to flow and perform better than stock vortec heads. If aftermarket aluminum heads can be in the budget, by all means go for it... but I'm betting many of them don't have heat crossover ports so watch out for that or we may be right back where we started.

But anyway, while I was driving and nothing better to do than think about stuff, perhaps we have been comparing apples to oranges with the whole heat crossover deal. You fellas that have had the bigger issues have been running a TBI type electronic injection. Perhaps the fuel puddling simply wreaks havoc with the fueling and the ECM can't decide what to do fast enough? Where as a carb just does it's thing based on the requirements for airflow. If there's fuel puddling, it just gets mixed inconsistently with the air moving past it and that's that. There's no O2 sensor telling the carb what to do.

No. The engine goes lean because the fuel separates and sits in the bottom of the intake. Doesn't care if it starts from a carb or TBI. It doesn't know the difference. Dry flow vs wet flow. The lack of heat crossover from GM never happened before the advent of Multi-port injection.

 

[Ricko1966]

Here's some good cylinder head comparisons

SBC Cylinder Head Info

 

[bucket]

No. The engine goes lean because the fuel separates and sits in the bottom of the intake. Doesn't care if it starts from a carb or TBI. It doesn't know the difference. Dry flow vs wet flow. The lack of heat crossover from GM never happened before the advent of Multi-port injection.

Initially, yes. But the fuel can only puddle so much before the airstream will start to carry it again.

I understand that GM didn't run a cold intake on a wet flow design. But that doesn't change the fact that who knows how many people have done it and in cold weather too. With a carb. Most of my experience with it was back before bargain EFI setups were available. I'm not saying the engine will run perfectly on a cold start... just that they can be driven gingerly on a cold start and when up to temp, it runs fine. Y'all that have run aftermarket TBI on a cold intake say that it's nearly an inoperative combo in cold weather, which means one of two things: Either cold start performance is much more discriminating than my own and the folks I've known, or there is a big difference between carb and TBI for the application.

 

[SquareRoot]

Initially, yes. But the fuel can only puddle so much before the airstream will start to carry it again.

I understand that GM didn't run a cold intake on a wet flow design. But that doesn't change the fact that who knows how many people have done it and in cold weather too. With a carb. Most of my experience with it was back before bargain EFI setups were available. I'm not saying the engine will run perfectly on a cold start... just that they can be driven gingerly on a cold start and when up to temp, it runs fine. Y'all that have run aftermarket TBI on a cold intake say that it's nearly an inoperative combo in cold weather, which means one of two things: Either cold start performance is much more discriminating than my own and the folks I've known, or there is a big difference between carb and TBI for the application.

I can't explain it. I just know from experience, it ain't worth the hassle. I understand your point of view.

 

[bucket]

I can't explain it. I just know from experience, it ain't worth the hassle. I understand your point of view.

Well I can't explain it either and just know from experience. Lol, sorry... I couldn't resist.

Just to be clear, I'm not at all trying to argue. I'm honestly curious why results vary so widely.

 

[Ricko1966]

I think there are too many variables, if everyone was running the exact same cam,compression,timing curve,at the same temperature,humidity,and barometric pressure etc. maybe everyone or no one would have troubles but that's not the situation almost all these builds are different and in different parts of the U.S..