honas

Are the stock LT1 heads worth porting or should I go with new aftermarket ones?

95CYC4

The stock LT1 heads are fine. I am going to keep mine when I get ready to upgrade my car. Spend the money on a good porting and valve job. Those heads can make plenty of power, as long as you got someone who knows what they are doing when it comes to flowing heads. Have fun. :cheers:

mackeyred96

Thats what I've got and I run OK.

SPD DMN

Me too.

GlockLT4

I Agree, eventually I will port and polish my stock LT1 heads. They will flow enough for a 400-500hp machine.

khornet

Any reccomendations for a shop to do the porting & polishing? What kind of cost am I looking at?

lcvette

if you are mechanically inclined and have some tools, you can probably do as i did and port and polish your own heads and intake. i have recently done the mods in my signature and i was the porter for my heads and intake, i did the port matching on both the intake and heads and the bowl work, the only thing i had doen other then this is a competiton valve job where the machine shop opened up the valave throat to help the flow numbers. i will be posting my new track times thursday night after going to the strip and should have some dyno numbers coming up here shortly. my track times will be verified by fellow forum members who attend the fayetteville drag strip. so they will be legitimate :D !!! as of right now, the cars sounds great and has phenominal throttle response as oposed to what it used to have. check back to see if the work i did turned out alright. i did all the mechanical work myself also to save money and be able to add more goodies. it was my first time into an engine like this, and for the most part, went fairly easy. it was no nascar speed job but i plugged along and got it done. took 4 weekends and 2 weeks after work from 5-10 to do everything including the porting and polishing. not too chabby i thinkfor a first timer and after getting her back together and the fuel primed and oil primed, i hit the key a vrooom cranked right up and sounds fantastic.!!!! through straigh 1 3/4" full length headers. anyways, good luck!!

chris :cheers:

95CYC4

My very good friend can do them. I am not sure on the pricing since I don't know how much work you want done(heads maxed out for best flow, or flowed for your cam) New valves, springs, angle milled, reshape the chambers or move the ports around, etc.. pricing can have a big range if you want race quality stuff, or if you want something for a street car you won't spend that much money. The guy is in NJ, so you would have to ship the heads. I know that he is very busy now anyway, but a good set of heads will cost you a few thousand dollars if you go to a well known shop. Heads is where the powers at, so it's up to you to decide how much you are going to spend. You could spend like a grand and get something really good, just depends on the pricing I guess. I wish you luck in finding someone good out there. If you get to some sort of big drag race in your area ask the super stock guys for the names of any good cylinder head porters. They will know who to go to. That's the only tip I can tell ya. Have fun. :cheers:

khornet

Bowl work?

I haven't been into working on engines since high school. Alot has changed since then. I suppose I'm up for doing the port and polish job myself just need to get the process details before I dive in.

SPD DMN

To get some good numbers you are best off paying a professional to do the heads. You can get some stage 2 heads which will be good well into the 10's on motor if that is what you are after. They will run you ~$2K with exchange. Give Chris K a shout chrisk@speeddemonmotorsports.com. He works real close with GTP which do some of the best heads in the business.

khornet

I'm not looking for a full blown hot rod ($2K! Yikes!!!). Being this is a convertible, I want to maintain some reasonable level of engine noise and reliability. My intent is just to make sure that the local Z-28's, Mustangs and assorted rice burners are kept in check. :D I'd like to stick with bolt-ons, but I think porting & polishing is a reasonable mod to be done.

At somepoint I'll start a discussion thread with my intended list of mod's so I can get input from you folks who are more technically inclined than I so I can make sure I'm on the right track.


[Modified by khornet, 3:38 PM 9/10/2001]

Chris@SD

Our stage II heads are a ready to bolt on set of heads. This includes full porting and polishing of the intake and exhaust. We like
to keep the runner size down which will give you phenominal torque on the
low side while still building huge power on the top end!
We also reconfigure the combustion chamber to aid in flame propagation.
We use only Ferrea 6000 series competition stainless steel one piece valves
in the stage II heads. The intake is 2.02" and the exhaust is 1.560".
The rest of the components are all Comp Cams chromolly super 10* locks and
retainers, spring cups, dual valve springs.
The price tag is $1999.95 on exchange. Yes, it is a lot of money, but no one is porting higher flowing heads and no one is making the power that we are! NO ONE!!!

Check out our Corvette Forum Mall for some of the products that we sell, including our heads and cam package! Our cams are all custom ground to our specs and are made from BILLET cores!

We build only the best stuff and we would love to build some for you. Let me know if there is anything that I can help you with.
If you are looking for something on a bit more of a budget, I would sugget our Stage I heads. We use the stock valves, mild porting and reconfigure the combustion chambers. These flow exceptionally well for using the stock valves and make great power also. They sell for $1150 also on an exchange basis.

Let me know what your needs are and we can help you out.
Thanks,

ce_me_vette

I also have a '95 LT1 that needs to have some head work done. How much of a difference is horespower and torqure does bigger valves, porting and polishing add to an LT1 engine?

nitrojunky

I'm running GTP stage II heads and have so far been very pleased with the sotp meater. On the F-body curcuit, they're well known for consistently producing fast LT-1 cars, and their heads generally go >400 rwhp na with a cc306 and the other requisite add ons and programming. I've seen as high as 450 rwhp na with a 396 and GTP 6 cam. This is from the ~240-250 rwhp of a stocker F-body. I'm sure that the competitor's numbers are similar.

In my experience the most power gained (short of nos or s/c) is in the heads and cam. Cost about $2000 or so + core, which I picked up used off a sale board.


[Modified by nitrojunky, 5:19 PM 9/12/2001]

Janaelen

I'm, using LT-1 heads fully done (Stage III). By using forced induction and NOS, from what I was told, these heads should suffice under my circumstances.

If you're looking for some good work, Exotic muscle does great and I beileve they're in Az.

They also did my programming blind for the supercharger and the cam. Everything seems to be o.k, but I'll only know after a Dyno pull.

Let us know how it turns out.

Chris@SD

We are typically seeing 380 RWHP(concervative) with a more mild cam with exhaust and programming and such on stock bottom ends. With a big cam, we a commonly seeing 400+ RWHP. As Nitrojunky has said, we have even seen 450+ RWHP on a 396 NA with our heads and cam!

Heads and cam is the MOST IMPORTANT piece of building a strong car. This is one area that should definitly be budget shopped. You might find some power, or you might be in the hole $1000 or more and still have to get a good set of heads.
GTP and us are proven perofrmers. You can buy our heads and cam in complete confidence that you will make great power and run fast!!!

Thanks,

khornet

What kind of horsepower can be expected with the ported/polished heads and other bolt ons without changing the cam?

Chris@SD

I would not suggest doing heads without a cam. These parts really need to compliment each other and need to be worked together. You will definitly pick up power(I have never done it, so I cannot give you any numbers) but I woudl still advise against it.
Thanks,

nitrojunky

I don't know if I'd do Stage II heads w/o a cam. I'd venture to say that they'd be worth 25-50 rwhp on a stock bottom end, but that is pure guesswork. They become more and more necessary as your modifications become serious.

The bottom line is, how far do you plan to go with your mods? Are you like me and never quit, even though you said you would last time? If so you probably want Stage II or so heads now, it will save you $$ in the long run. If you think you'll stop at a certain level, say <350 rwhp, then a milder, cheaper version might be better, e.g. mild port & polish, etc, flows ~240-260 max in, costs ~$1k (excluding r&r).

Regardless, the better the heads, the more you'll get out of each modification you do, bolt on or not.

Also keep in mind that your bugdet must include things such as head gaskets, intake gaskets, H2O pump gaskets, head bolts (always use ARP, that way they're reusable if there's a next time), rockers, reprogram, RTV, etc. It can really snowball... ask me how I know.

ce_me_vette

If I put in a new cam, I'll be looking for a cam that offers good overall drivability on the street and highway, but at the same time offers additional performance to compliment stage II heads. Any recommendations guys?

Also whats the impact as far as fuel economy in terms of mpg for city and highway when modding heads and cam?


[Modified by ce_me_vette, 11:20 AM 9/13/2001]