Tim37chevy

whats the horsepower potential of a stock head 99 ls1? i'm talking like you change camshaft rockers springs intake throttle body and get it tuned for 93 what is the best you can hope for i have a 37 chevy that with this engine does pretty good with that 6 speed even though the gears are to high even for the street 29inch tires with 4.11s. i'm kinda stuck with sucking hot air due to clearance between the engine and radiator. i thought about doing a mild porting and back cutting the valves.

JUSTINSWS6

Well i know of cam sc on stock 241 heads over 600rwhp

Tim37chevy

sorry i should have said n/a i know that boosted i'd easily obtain more power than id ever need but it be cool to get in the 400rwhp numbers i know a guy with a ls2 thats making that but don't know if it can be done with the ls1 and still be street friendly

Rare96LT1Formula

iTrader: (32)

I'm running stock 853 casting heads on my 2000 LS1 (Almost identical to 241 casting I'm told). I've been searching around looking at getting them cnc ported/polished and a multi angle valve job. So far, I've been hearing about gains anywhere from 25-40 rwhp. Advanced Induction is one of the companies I've been in contact with. Their work speaks for itself. I've also spoken with AES Racing about performing the same work. The bottom line is, you can still make sizable power increases with worked over stock castings. Be prepared to shell out some cash, but for the money you will see some nice gains.

CustomX

iTrader: (1)

My car made 389rwhp with stock 241s, worn out valve springs and a banged up ypipe thru an a4. There are a bunch of people who have made over 400 rear wheel with stock 241s.

JUSTINSWS6

Youd be lucky to get 20rwhp

Rare96LT1Formula

iTrader: (32)

Thanks for that load of steaming crap. Maybe do some research next time you go making claims you cannot support.

http://www.advancedinduction.com/LSX...cGMLS1Head.php

JUSTINSWS6

Ok ya go spend that to gain 20 if lucky they will tell you anything to fet you to buy anything. Some better heads dont even gain 40rwhp so how is p&p going to?

Rare96LT1Formula

iTrader: (32)

Honestly, I could only comprehend about 60% of that post. Your post in general, is full of misinformation. There are plenty of aftermarket castings making over 40rwhp. Not sure where you generated that information from either.

Advanced Induction is VERY well known in the LS community and I can assure you they are NOT making empty promises. There is a thread in the Dyno section of a member here making 49rwhp just from there cnc porting on his 243 heads. Hard to argue with results. Might want to do some more research before you start making suggestions around here.

farmington

iTrader: (14)

Girls, Girls. Quit fighting. First of all the post was about 241 heads not 243 heads which are much better especialy when ported. You're not going to get 40rwhp from p n p 241 heads. Period. Maybe if you have an incredibly huge cam that runs like crap as a before porting example.

Tim37chevy

whats the difference between gaskets 12498543 and 12498544 are they really different or just the thickness?

Rare96LT1Formula

iTrader: (32)

Agreed. Which was why I was speaking about the 862 casting which I'm told is almost the exact same cylinder head. Lots of misinformation was being spread there, and thats not the goal of these forums... to my understanding at least.


Straight from AI's website:
Typical gains for our CNC work are in the 40rwhp SAE range over the as cast 241, and many 346cid LS1's manage 420-460rwhp SAE with bolt-ons and one of our daily drivable HR cam grinds.


I'm not going to debate proven results with you, I'll let the sponsors do that.

JUSTINSWS6

No they are not dont flow as much cfm as the 241. But you have a "rare" car so...

Rare96LT1Formula

iTrader: (32)

Just realized I posted the incorrect casting numbers. They're actually 853's which are essentially the same cylinder head as the 241. Regardless, I'll post a build thread and be sure to send you the link when completed sir.

JUSTINSWS6

yes because i have only seen 241 p&p got 24rwhp so i dont think you will gain any more. I just didnt want you to think you will gain over 25rwhp so you dont get your hopes up. I hope you can get 40rwhp but i dont think that will happen.

Rare96LT1Formula

iTrader: (32)

I understand now. I was merely trying to give the OP a realistic idea of what his stock heads could do. Obviously, it's all going to depend on who does the work. In my experiences with aftermarket modifications, you usually get exactly what you pay for. In the case of Advanced Inductions, and TEA, I have no reason to doubt their claims of 35-40 rwhp gains.

sepsis

iTrader: (7)

From AI: "Typical gains for this CNC work are in the 40-55rwhp SAE range over the as cast 241, and 346cid LS1's can manage 440-470rwhp SAE with bolt ons and one of our daily drivable HR cam grinds."


With a cam and bolt on's.

JUSTINSWS6

Well after using the "Google" i found that the 853 heads are sand casted not die casted which gives the 241 better flow. More cc. I also saw everyone saying dont put any money in to 241 or 853 heads. They all said get some used 243's which out flow the 241's by a bit. So if i was you i would buy a used set of 243's for 400 bucks then maybe get them ported and polished and you would gain some where in the range of 40 rwhp. that is 243's p&p vs. 853 heads. Which is well worth it in my opinoin have well less than 700 dollars in heads and gain about 40. This is what i would do on a buget. If your not on a buget or want to spend a little more look up some tsp ls6 heads or 5.3 heads. If your not on a buget get some afr 210's, 215's, or some tsp prc 215 heads. These three heads are very nice and show big gains.

Rare96LT1Formula

iTrader: (32)

Of course with cam and bolt on's!! Is someone just going to get extensive cylinder head porting done and ignore everything else?!?!?

OP was wondering what his STOCK heads could do.

sepsis

iTrader: (7)

I know. I was just pointing out the gains the heads could make with cam and other stuff.