SATAN

iTrader: (2)

I just picked up an LQ4 engine and it has the cast iron heads. I am under the impression that these heads are garbage and I should get different ones. However, there are so many different head casting numbers, that I don't know where to start.

There is a local guy to me that is selling some aluminum 317 heads off of another LQ4 has springs and valves. He says they flow the same as the LS6 heads. He is selling them for $200. Any good?

Then another guy selling 6.0LS heads with LS6 valve springs for $125. I don't even know what a 6.0LS is. Is that an LS2? I know the LS2 is a 6.0 so...

SOMbitch

iTrader: (8)

The 317 are essentially the LS6 port with a 70cc chamber that will drop your compression. Strong FI heads but not that great for a NA head. You want 243/799 heads that have a 64cc chamber and get your CR up. LS6 243 heads have the lighter hollow stem intake valves and sodium filled exhaust valves and bring a couple hundred than the normal 243/799 heads. You can mill 317's to bump compression but you lose PTV so hold out for 243/799's...

LS2 is the aluminum 6.0 and has 243/799 heads. Look at the casting # on the head not the engine...All the iron 6.0's have 317 heads but the LQ9 has more compression than a LQ4 because of a flattop piston instead of a dish...

garygnu

if you don't go with a radical cam the milled 317 will work,get new springs .if the 6.0 heads are 799 get them and new springs that will work with a power producing cam..do a valve seat test and fill the runners with fluid to see if the valve seats leak.

Sales4@Texas-Speed

iTrader: (4)

I think the best thing you could do is try to find some LS6 heads. The extra compression will pick up power everywhere, especially in the low end rpm range. Compression is key on these motors to making good power and keeping drivability.

SATAN

iTrader: (2)

Terribly sorry...

I should have stated that I am looking for 317 heads specifically for low compression, as this will be a turbo application.

I am under the impression that the 317 flow the same as the LS6 heads (which is good), but obviously have lower compression (what I'm after).

However, are the cast iron heads I have junk, or do they flow the same as the 317 aluminum heads? If I can find some aluminum 317's I will get them... but so far I can't find any local, so are the iron heads just as good, but heavier?

I was looking all over the heads with a flashlight. I did not find any three digit numbers for the casting. There was a really long number, but I figured that was a serial number.

Madellous

take the last 3 digits of that serial number.. that is you 3 digit casting number

SATAN

iTrader: (2)

Hmm, it was 875. A search didn't pull up anything on that.

EDIT: Searched here and couldn't find anything... Searched Google and found this LOL. Basically, they are not that great from what I understand.

https://ls1tech.com/forums/generatio...uild-help.html