vbls

iTrader: (17)

i have a 00 automatic with nitrous, headers and a few other mods. my heads now are the 853. will 243 heads help a lot with the stick cam? ( dont want to do a cam now because the torque converter is stock.)

WS6tx

iTrader: (25)

YES... They will help Quite a bit, not only do they flow better stock over 853. they have a 64cc combustion chambers which will raise compression, providing more power n/a and with the gas. They will benefit you even more down the road when you due your cam swap.

mtuggle86

iTrader: (7)

I don't think there gonna help you much at all except you'll get a .5 bump in compression. A 2000 stock cam is only .500 lift so its not going to be able to capitalize on the 243 heads better flow. The 243 heads only have limited gains in flow over 853 heads under .500 lift. Id honestly say you'll over pick up 10rwhp and half of that will be because the increase in compression.

1990LSx

iTrader: (9)

You will benefit from the head swap for sure and you will add that much more power when you decide to do a cam swap in the future.

VincesSS

iTrader: (1)

They flow better and have better compression, they will definately help. Any hp guesses is pure speculation unless they've done it.

I'd cut them .020" to give you a little more and do the lifters and good valve springs while the heads are off so your cam swap down the road will be a piece of cake. Good luck.

intenseblue

iTrader: (1)

They will help. Gains will be larger when you cam it. I would not mill them though unless you have them ported. I would spend slap them on as is or use a thinner head gasket for a compression increase. Cost would be the same after paying for a mill then stock gaskets.

180ls1

iTrader: (4)

I wouldnt mess with it because of the tuning costs and hassle involved. I would though once you cam it and get a better converter. Personally if you are looking for more power i would up the jet size and maybe pull some weight. That would be very cost effective.

mtuggle86

iTrader: (7)

It really doesn't take much to see his gains will be very small unless he has a cam to take advantage of the ls6 heads. The only time hes going to so etra flow from these heads is right at his peak lift from .400-.500. Most people with cams only pick up 15-20 rwhp from stock 243 heads without a cam he's gonna be lower then that for sure. Here's ls6 vs ls1 head flow numbers notice how there's hardly any gains until you go over.450 lift. Most of his gains will be from the increase in compression and a .5 bump is only worth about 5rwhp.

http://www.smokemup.com/tech/ls1.php

vbls

iTrader: (17)

ok 2 questions, can i put bigger springs with a stock cam? like .650 lift springs?

also you have to get a tune after a head swap?

mark21742

Yes you can go with a heavier spring, but you will want to have ot shined to raise its seat pressure some since they are made to run higher lift....if your going to FI a head swap now is get them milled some and ported before you put them on so you won't need to pull them later to have the work done on them, and like said above I'd do lifters too while you have them off.

Do you need a tune for a head swap? I won't say yes, but you are changing your air flow characteristics crossed the whole rpm range so i'd highly recommend a tune.

If it was me I'd do a converter 1st. This will give you higher gains than just a head swap, but if you need to pay for every tune I'd get all the parts together, install at the same time and then get one tune....it won't hurt your parts to lay on the shelf for awhile till you get everything together.

I agree with the others and don't think you would see much gain with even the best ported heads running a stock cam, but you'd see the gains once you dropped a cam in

groundZ-28ERO

i noticed alot of difference with mine,
ported 243's, stock cam
got mine for free from a buddy with a 03 zo6

shawn_c992001

Will they help? Yes. Will they help later after a cam swap? Yes.

The springs already being in will help later too, as will a port and polish job.

RoidedSS

if you can pick them up for cheap, i would grab them. it will have u ready for your future plans. if you have an idea on the cam you want you could get the heads worked for your future plans. I'll be sending my 243's to AI at the end of fall. Their work is showing some impressive gains. Or, like a lot of people are saying just wait until you have everything and do it all at once so you only have to tune once and save the $400 dollars to have it tuned over and over

mark21742

Or if you feel up to doing some learning, buy hptuners for $650 and do your own tuning as many times as you like....or get a friend or two to go in with you and split the cost

I'm still in the " I have noclue what heads to buy" category....but I know I'm to the point that I need them because I'm sure my ported/ milled 241s are holding me back

itsslow98

iTrader: (18)

why not do 243s and an ls6 cam? youll see much better results and be able to utilize the stock converter still.

98sivlerbullet

iTrader: (1)

I am in the same boat here buddy gave me some 243 heads for free and I am getting a hook up on a tune in mid June. Idk if I want to throw the 243 heads on with a stock ls6 cam for now or wait do ported heads after market cam later. Just flat broke right now if it cost around 200 bucks for all the gaskets head bolts etc for me to put them on ill do it.

180ls1

iTrader: (4)

agreed or i would favor a 224/224 on 114 if i was changing cams that way i could save the tuning hassle and have a cam that would make better power. That cam will work pretty good with a stock converter.

buzb026

iTrader: (1)

do you have any before and after results from putting just the heads on??

IRONFIST

Right now I have 243's on a stock cam car. I picked up a couple MPG from the swap, but also picked up power. My best friend own's a 370Z, before the swap we would be dead even from a roll... now after the 243's and LS6 intake I walk away every time.
How much that is in the quarter I don't know....
Also I have not tuned the car.

98sivlerbullet

iTrader: (1)

Did you do the head and intake swap at the same time? Cause a ls6 intake makes a really big gain for what it is. It felt like night and day deference after my swap on the street and went from 8.7s to 8.2 in the 1/8 after my swap.