Heads? Which ones to start with?

**2kbluws6** · 04-05-2007, 03:46 PM

Looking to get a set of stock heads and do them up myself. The question would be which heads off of a stock motor would be my best option? I cannot have mine done because this is gonna be a back burner job for a machine shop...So i am going to look at goin all out on a set that i buy. Prolly gonna go with titanium valves, full port job. bigger valves, and milled way down...

Plans for the car are keep the stock cubes for now, but it will be at leasta a 427 if not bigger when i rebuild it. so if they are too big right now for the stock cubes and i loose a lil in the #'s then it is fine, but i dont want to have to redo them in the future.

what heads should i be looking for and what should they be off of?

Tim

**juiced99ws6** · 04-05-2007, 08:19 PM

I am pretty sure that most heads that you find that will be compatable with your stock cubes will choke out a 427. I am pretty sure the L92 heads are the best and cheapest option out right now as far as stock heads. They flow about the same as AFRs before any machine work. Only drawback to them is the fact that you will be unable to use them with your stock LS1.

**2kbluws6** · 04-06-2007, 12:16 PM

Originally Posted by juiced99ws6

Only drawback to them is the fact that you will be unable to use them with your stock LS1.

WHat makes them not work? what would the options be if i used these heads if possible? Would they be suitable for a big cube motor if done up with lots of porting and polishing?

Originally Posted by juiced99ws6

I am pretty sure that most heads that you find that will be compatable with your stock cubes will chock out a 427.

what would be a suggested option?

**2kbluws6** · 04-06-2007, 05:57 PM

any help here guys?

**LS2Tuner** · 04-06-2007, 10:02 PM

I would do a pair of the L92 heads!!
They flow SOO much better because the intake port is like a rectangle port on a BIG block head.
Yes they will work on your LS1 but you'll need a new intake that has rectangle ports instead of your cathedral stock ports.
A good machine shop with a SERDI valve machine should be able to do some cutting on the bowls and then havd blending to get MORE than enough flow for a NA 427. We run them on 450"+ motors than way with just bowl work and stock valve sizing and they work great!!
People ALWAYS want bigger valves when they are not needed. It's just like Hydraulics the smaller the restriction the faster the volocity.The ports will flow plenty and without loosing all that volocity by putting BIG valves it will have AWSOME throttle response and take even more advantage of the tq.

You should be able to get the bare castings for $300ish ea.

Thats my 2 cents.

**2kbluws6** · 04-07-2007, 07:16 AM

What could i find a set of heads off of that would have the L92's? and what would i need for an intake? Like an intake off of a truck? i am kinda new with the internals of the LS1, i am more old school and big block performance...hence the 800 horse 81 BBC Camaro drag car.

**2kbluws6** · 04-07-2007, 07:56 AM

another question...i am reading about the L92's and they say the should only be used on a 4.0 in bore...isnt the bore of a ls1 like 3.8-9? will they fit if i use the L76 intake?

**juiced99ws6** · 04-07-2007, 10:10 AM

Originally Posted by 2kbluws6

another question...i am reading about the L92's and they say the should only be used on a 4.0 in bore...isnt the bore of a ls1 like 3.8-9? will they fit if i use the L76 intake?

im not sure if LS2Tuner knows something about them that I dont know but yes the L76 intake would be needed (sorry I forgot to mention that before) Also the L92s are supposed to not have valve clearence or something to work on the LS1 because they are designed for a bigger bore engine like you mention. GM is supposed to be comign out with a set that is LS1 compatable from what I read but as of now there isnt one and by the time it comes out then you will probrably have already upgraded. My advise would be to buy a set of L92s now and leave them off the car and just save up some money to buy retainers, springs, and LS7 lifters and have the machine work done to them that was mentioned above. By the time you get your 427 then you will have one hell of a combo

**juiced99ws6** · 04-07-2007, 10:13 AM

Originally Posted by 2kbluws6

What could i find a set of heads off of that would have the L92's? and what would i need for an intake? Like an intake off of a truck? i am kinda new with the internals of the LS1, i am more old school and big block performance...hence the 800 horse 81 BBC Camaro drag car.

they come from the new escalade but you can just purchase them from GM

**2kbluws6** · 04-07-2007, 04:14 PM

well on the idea of me doing the L92 heads now and not using them on this motor, would they fit the ls1 block when it is bored to whatever sisze is needed to make it a 427 minimum..i know it is also stroked, but that has nothing to do with the block...???

**juiced99ws6** · 04-07-2007, 05:23 PM

it will just have to be bored to at least the same as an LS2. shouldnt be to difficult.

**Frankthetank** · 04-10-2007, 06:37 PM

Originally Posted by 2kbluws6

WHat makes them not work? what would the options be if i used these heads if possible? Would they be suitable for a big cube motor if done up with lots of porting and polishing?

what would be a suggested option?

Accually man Im almost positive the l92 heads woont work because the bigger ls2 bore.......

**LS2Tuner** · 04-11-2007, 04:00 PM

Originally Posted by juiced99ws6

im not sure if LS2Tuner knows something about them that I dont know but yes the L76 intake would be needed (sorry I forgot to mention that before) Also the L92s are supposed to not have valve clearence or something to work on the LS1 because they are designed for a bigger bore engine like you mention. GM is supposed to be comign out with a set that is LS1 compatable from what I read but as of now there isnt one and by the time it comes out then you will probrably have already upgraded. My advise would be to buy a set of L92s now and leave them off the car and just save up some money to buy retainers, springs, and LS7 lifters and have the machine work done to them that was mentioned above. By the time you get your 427 then you will have one hell of a combo

YES YOU ARE CORRECT THEY WILL NOT WORK WITH THE SMALL BORE SIZE ON THE LS1!!

The port volume would be rather large also for that small bore........ It would be ok for a race motor but I would not chose those for a street motor combo on a NA LS1.
If I was you I would just buy some stock castings and take them to a machine shop that has a good rep at your local drag strip.
Talk to the braket racers that are racing EVERY week and get there opinions on who they use and don't use. You'll learn alot that way. As most will find they will only be 2-3 shops majority uses.
Make sure they have a SERDI valve machine. And remember BIGGER IS NOT ALWAYS BETTER!!!
You loose LOTS of port volocity by putting a big valve and if you have a small bore the benefit DOESN'T out weigh the gain.
REMEMBER YOU WANT YOUR POWER TO BE SOMEWHAT LEVEL ACROSS THE POWER BAND NOT LOOKING LIKE A SPIKE!!

This should help all you others with part #'s needed too..... http://www.gmhightechperformance.com...ine_l92_heads/

**2kbluws6** · 04-11-2007, 04:48 PM

so what should i be looking for them off of? a truck? a car? stock heads of a f-body...i have connections at local salvage yards, i just need to know whaqqt should i be getting them off of? and as of this morning we got close to 3 inches of snow,.. so the car is parked till the first large rainfall to wash the salt away.
Tim

**LS2Tuner** · 04-11-2007, 05:31 PM

You can get castings off of any car with a LS1 or even LS2. If you plan on spending money getting them ported it won't make 2 big of difference which ones you start with.
If it was a cast iron head it would different cause they take hours and hours for us to port. But being alum. it is very easy to reshape runners and bowl mouths.

You can have the SNOW thats why I left back east and came out here 8 years ago!!

We dragrace year round out west here........