I'm new to the LS world and can use some help. I purchased a LQ4 with aluminum 317 head. I would like to gain some more hp but keep the same heads.

I have purchased a LS6 intake And now I am looking at milling the heads and getting a cam.

Does anyone here have any recommendations on how much to mill the heads and what cam to use. I want something steetable but a lumpy cam. Any help would be appreciated.


Thanks!

 

Not sure how many .001 to tell you, but I would suggest aiming for about 64-66 cc combustion chamber, which will put compression near LS2 levels.

Generally, I would say buy a cam for power, not sound. You can always tune a cam to sound cool at idle.

If you want a lumpy cam that pulls hard in a broad RPM range, I would go Tick SNS 2. That cam has alot of overlap, so it can tricky at low rpms. The cam motion titan 4 would have less overlap, so the manners would be better. both cams are 227 degree intake cams.

If you don't have long tube headers, you will need them for any cam that has decent overlap. The stock manifolds will work against you if you try to keep them. If its going into an automatic, you will need a higher stall converter as well.

Hope all that helps

 

The 317 head chamber is a bit deeper than the others but the overall shape is pretty much the same. The average is about .006" per cc on a small bore head. To go from 70 to 64 you'll need .036" shaved off. Which of course reduces PTV clearance by .036". On a mild to med mild cam this is not an issue. Big exhaust on a narrow LSA will cause problems.

I'd say sell the 317's if staying N/A and get some 243's(64cc chamber). The 706/862 (62cc chamber) heads will up the CR too but at a lower price and slightly smaller intake port(200 vs 210) but still better than the 241 or 853 heads.

 

Also, "streetable" is a relative term, so very subject to opinions on what is acceptable.

My cam, if I dump it in third and let it idle, it will run about 15 mph and buck occasionally. I think it's perfectly streetable, because I've learned how to drive it. My wife thinks it isn't streetable at all, because "It runs rough until you get up to speed"

What are you willing to live with?

 

Thank you for all your responses. I have read numerous posts and everyone is saying to go with the 243 heads. If I do go with the 243 heads would I have to mill them or just keep them the way they are?

 

The 243's stock should put you right at 65cc's.

 

What fuel do you plan on running. The 243's with a .051" gasket and stock short block will net you about 10:1CR. Pistons are about 7cc dish and out of the hole about .004-.008".

I'd say mill them to 60cc and run a .045" gasket if running 91+. That would put you at about 10.8-10.9CR. Cam matters too but anything LS6 to mild 220"s will be more than safe. There is more to it than that obviously(events) but more CR makes for happy tq. :-)

 

You guys are genius, I'm clueless when it comes to this as I'm still learning. I will be running 91 octane or higher. What cam and lifter setup would you run if I killed the the 243's to 60cc?

 

Cam motion titan 4: http://store.cammotion.com/the-titan4

LS7 lifters

stock rockers with comp trunion upgrade

BTR dual springs w .660 lift

 

I found a set of truck 243 heads for a good deal. Are they that much different from the zo6 heads?

 

Only difference is the Z06 heads have lighter sodium filled valves

 

What type of power do you think I will get with this setup? Ls6 intake, hooker longtube headers, 243's milled with the above components mentioned. I'm running a 4L80e, it has a stock converter at the moment, not sure what it is or what I should run.

 

I got a set of 243s an ported 317s. I sent u message about bout 317s

 

TO be honest, I'm not sure. I would normally guess in the 420-450 range (depending on dyno, tune, etc), but I have no experience through a 4L80. I've heard it has higher power draw. You'll want a higher stall converter, but again, no experience with the 80. I would probably go 2800 stall if it were a 4L60.

Sounds like a fun build. It'll be a fun motor on the street

 

Do you reccomend anything else other than the btr dual springs, those are super pricey.

 

They are my default. If you talk to Kip at cam motion, he might be able to give you better options. The PAC duals might be cheaper. I'd hesitate to go beehive on anything over 600 lift myself and price duals.