weatherkid

I'm gonna be getting some money from tax returns and want to purchase some new heads.. so cost isn't much of an issue i just want some great heads that i'm not gonna regret getting. I want something that will work well with my current cam but make MORE power. I only drive this car a couple hundread miles a month.

i just want to go faster and think that my heads are what's holding me back

96capricemgr

iTrader: (1)

The whole car reads like a list of what not to do.

Why the low compression?
The cam was a mistake.
Holley TB is more trouble prone than other options.
Accel injectors are supposed to be better now but were long garbage.
Why the TH400, with a 3400 non-lockup can't be much of a street car, GV is parasitic
2.73s should be the first thing you change

Actually quite suprized it has run a low 12., was the weather spectacular or is the car lightened?

Ported stock heads are the right choice for the vast majority of LT1 builds, problem is you already had them halfway worked which means you probably have to come up with another set of cores to make it right.

On second thought maybe the heads are pretty good, flow bench numbers are not the ideal measure of a head and this thing is working well considering all the bad parts so something must be right.

weatherkid

ha thanks i know.. the whole thing is a mistake.. an expensive one that sat untouched for over a year now. i've been distracted with modding my DD the gtp. but i'm wanting to try to do something more with the Z now.. now that i've read enough to know i messed up. but yeah, money and no knowledge makes for a bad combo.

the original builder told me i couldn't go much high compression on pump gas.
the injectors i believe are better than the older ones.
yeah i had to do some welding and grinding on it.. i ran into trouble twice w/it

yeah the GV and all set up.. pretty much a 2500 waste of money at least it works.. it does give me better times at the track thru the th400 and GV, than the stock trans with just a vig 3200 lockup

the 12.2 @ 113 was bout 80 out back in summer.. and no the car is probably 200lbs heavier than stock.

I guess i can try to turn it into more of a drag car i dont even care bout gas mileage really, I just want to be able to drive it on PUMP GAS on the streets. since the flexplate back is headed that way already i guess why not throw a bigger custom cam in and whole new heads.. I'll do it, i got about 3k. i just wanna get it right.

chuck1980s

I hear AFR heads are the best pound for pound. That is if you have the money for it.

SincalT/A

iTrader: (16)

No,stock is the best for the money.If you do not think so then thats fine but the majority believes otherwise there's a poll floating around in here if you want to research it. Search (Whats the best head for the money) Btw. Where do you live in Ca.

tylert14

iTrader: (11)

Keep your heads. Fix your other mistakes first. Your throttle body is fine, your injectors should be fine. Change the gears and the cam. What tires are you using? Def need some drag radials. Please don't get QA1s. What tune or you running now? A mail order?


If you do all that and you still want to get heads go for it. No sense spening 1000+ on heads when you have other things that need fixed first.


Sorry If I asked anything you allready mentiond. I had a few beers LOL.

96capricemgr

iTrader: (1)

Just to give you an idea of why you would have been better off using a builder that had a clue about an LT1. I am running 11.2-3:1 on a stock shortblock in my big heavy pig of a car on pumpgas, mailorder tune.

There are true street LT1s out there topping 12:1, the reverse flow cooling, computer controls, modern chambers and understasndings of quench all comspire to allow us to run substantially more compression than gen 1s.

The iron head LT1 was 10.0 ran in cars that are up around 4700lbs without driver, f-body and Vette LT1 was 10.4 ran on 91 octane from the factory, can be retuned for 87, LT4 was 10.8 from the factory again 91 octane.

A LOT of LT1 guys have been steered wrong by gen 1 builders like this.

On the tranny setup I wonder if the really bad rearend gears are why the TH400 GV worked better. The 4L60E with a stall takes a lot less power to turn.

Like I said something in that setup IS working, a lot is wrong but it is running suprizingly well. The most mysterios part is the heads so I would be inclined to keep them for now. That said IMO Advanced Induction is the best LT1 heads you can buy.


chuck1980s, AFRs have a LOT of POUNDS too them, heaviest aluminum head I ever handled and I have handled some big block aluminum heads.
They have this wonderful REPUTATION built when OEM heads were garbage and easy to improve upon, the LT1 head was like a 15%+ improvement over all that came before it, and AFR simply tried to keep selling their old outdated gen 1 ports and tweaking the castings for our cooling. End result is they were not a good idea on LT1s, some guys do have sucess with them if they go big like the 210cc and then port them.

AFR basically admitted their whole lineup was outdated junk when they recently redesigned EVERYTHING and things are pretty well untested since the redesign.

A friend has a small set of ported AFRs on his camaro, as a heads and cam car it was no faste than my car was with just a ZZ4 cam, today he has a stroker under them with a 239/239 cam with more lift than my much smaller lift and duration cam, and is still slower. He wants me to sell him my outdated AI heads(his old heads) and let me step up to AI's 200cc so he can get rid of the AFR crap.

I will say the most impressive Impala 90s out there runs AFRs, the 227 with a little work, BUT it is a donovan aluminum block modified to take everything LT1 434ci 15psi and a baby shot of juice to cool it means it is in no way comparable too the little NA builder we talk about. He just needs a BIG hole to cram air through, when he planned a mild boost engine for a friend they went with AI ported stock castings.

Also consider there are individuals that will make anything fast, there is a bolton Impala running 12.3, can't imagine what my car would do in that guy's hands but I suspect a rollbar would be required. Best I ran with a mild cam stock heads was 13.2 in great weather so I am not a guy who gets every last tenth out of a car.

FASTFATBOY

iTrader: (23)

#1 Put a 4l60E BACK in the car with a GOOD converter. Selling the gear vendors and turbo 400 will cover this. AND get weight out of the car.

#3 Put a 3.73 gear in the car. Stock rear is fine. You DO NOT need a 9 inch rear. I have seen full weight cars run in the 10's on the stock rear...Hell I dont need a 9 inch, it is a leftover from when the car had a six speed.

#4 The heads at 255cfm are "ok", car needs compression, either mill the heads and/or a thinner Impala head gasket. I run 12.6 to 1 on pump gas.

#5 Cam is ok

#6 Put your suspension on the car that you already have.

#7 Have it tuned on a chassis dyno.

This car will run in the 11's with this little bit of stuff.

David

weatherkid

well with my tax returns im gonna use it for the rearend to start with, and leave the cam and heads for now..

I'm running mickey ET street radials at the track there a good tire, they hook great no prob droppin the the t brake at 4000, they dead hook.

I'm just gonna put all the suspension on that i have sitting i got the qa1's for a good price, with those and the 3.73 i should still hook good with the mickeys.

AS for tune, i got it dyno tuned on a mustang dyno in clinton township, mi at Vector Motorsports. using lt1 edit and a wide band. there very reputable for lsx and ltx motors.

weatherkid

I forgot to metion i have NX dual stage wet Kit hooked up w/ progressive controller & msd digital 6 and currently jetted for single stage 150 shot, so with that and the t brake, i'm not worried about a little overkill with the drive train. I want it to be strong. I've went lmid 11's on spray this year at 122, but plan to return to have it tuned at Vector motorsports again with spray once i get the rearend in.
then i'll see what i get at the track before i plan anything more

LT1Formula007

iTrader: (66)

Fatsfatboy is on the right path.
Leave the heads and cam alone for now at least.
I'd definentely get the suspension on there and Definentely get the 2.73's out of the car. Keep in mind that when you put 3.73's in there traction will most definentely be an issue. And the fact that they spin faster means your gonna take a chance of breaking the rearend on the MT ET's. I broke mine using 3.42's with slight bolt-ons and with the 2.73's no matter how hard I launched the rear was fine. Just something to keep in mind.
A better cam matched more to your setup would help.
And last but not least....Just so you know I'm building a 383 with 11.8:1 compression and with Premium gas it will be fine as well. I think you got someone to build you a motor who knew very little about the LT1 block. Which is fine, but your just gonna have to search and find other ways to compensate for power loss with the lower compression ratio.
Good Luck Man.
James

flyinZ

iTrader: (15)

If your dead set on getting a set of heads..Id get the TFS 215 or the Darts from AI..I've seen awesome #'s from those...and the Darts have KILLER potential.

tylert14

iTrader: (11)

How big is your urge to go faster? How far do you want to go? If you want to get all you can out of those stock heads you need to get your CR up. I was using 12.5:1 on 93 as well. Find a CR calculator and see what you can get it down to with the thinner gasket. I pretty much covered everything in my other post. A new tune from the place you mentioned would help when you do all the changes.

As for the QA1, I will never recommend them to someone unless its a strictly track car. Search the suspension section for strano. QA1s will make your car ride like a bag of soggy potatoes. Not worth it for a 10th or 2 to me. People have had excellent results with Koni shocks and disconnecting there sway bar at the track, and it's a killer setup for handling once you bolt the sway bar back up. I would personally sell your shocks.


Your rearend may hold, it may not. Luck of the draw.