Gen V L86/LT1 Heads on L83 ?

[Spurshot]

I'm thinking about putting L86 heads on my L83, but don't know if the valves will clear the cylinder walls.

 

Anyone have any information on this?

[Stoddard]

Compared to the gen 3/4's they will be so close if not hit. The shrouding of the valves kills any gains you may make anyway.

[07Softail]

I emailed Lingenfelter and LMR for this info and have not heard back yet and I have been thinking the same thing. The valve angles are 12.5-12 degrees that i know and you can get these pretty cheap at GM parts direct like $370 each or something like that.

 

RT

[Spurshot]

I emailed Lingenfelter and LMR for this info and have not heard back yet and I have been thinking the same thing. The valve angles are 12.5-12 degrees that i know and you can get these pretty cheap at GM parts direct like $370 each or something like that.

 

RT

I did the same thing. They never did respond. A head with valves, springs, retainers, is around $500 ea

[07Softail]

Well HP-TRQ Junkies.... I heard back from one Company (Extreme CFM porting) Never heard of these guys but they said the heads won't fit because of the 3.780 bore and the large Intake valves. Tim Dyer @ Lingenfelter is doing a mock up on a 5.3 to confirm. Dang I was hoping for some really good gains with a good set of heads and a relatively cheap bolt on too.

 

RT

[newdude]

Should be a no go. 6.2 is 4.125 inch bore. These engines should be pretty much like LS Gen 3 and 4, in where LS3/L92 heads need a minimum of 4 inch bore (LS3/L92 will fit a 6.0 and up no issue). 5.3 is under that, 3.78 inch bore.

[07Softail]

Actually the 6.2 has a 4.060 bore.

 

RT

[newdude]

Actually the 6.2 has a 4.060 bore.

 

RT

 

My bad was confusing up my numbers lol I guess the LS7 was on my mind.

[iCryWheniGoPoop]

I would bet that you can have your L83 heads worked for less than the cost of two LT1 heads AND get as good or even better results.

 

There are L83's putting 400+ hP down at the wheels with cam, headwork and exhaust.

[07Softail]

I would bet that you can have your L83 heads worked for less than the cost of two LT1 heads AND get as good or even better results.

 

There are L83's putting 400+ hP down at the wheels with cam, headwork and exhaust.

That's my next plan... Gary Williams is a local Head Porter told me that the smaller runners of the L-83 heads would be a better starting point because you can finesse the ports for velocity better than a port that's already enlarged.

 

RT

[Evanski9]

Very interesting!

 

I am still on the hunt for the perfect cam. Not to many people swapping yet.

[Spurshot]

Very interesting!

 

I am still on the hunt for the perfect cam. Not to many people swapping yet.

 

Not a lot of choices either.

 

Assuming you have a 5.3L since you posted on a 5.3L thread...what characteristics are you thinking about?

 

I ended up buying a 6.2L L86/LT1 cam. My desire was to retain the full variable timing range of the OEM system and keep fuel economy when not demanding more power.

[07Softail]

Thats the camshaft I have also...I think it will give a slight boost in power and as you said maintain the valve timing of the stock setup.

 

RT

[Evanski9]

I have been looking into this. My goal is not to move the power band to much

 

cc503: (224/230 .537/.544 112lsa) w/ 1.6RR's
Widely known for being the biggest cam you want to run on a stock headed car without sacrificing usable power and drivability. Features Comp’s relatively newer XE (Xtreme Energy) lobes for increased top-end power. Has a very strong mid-range with strong top-end power without much if any loss in the low-end. Similar to the GM846 and good for a solid 10-15hp/tq throughout over the “Hot Cam”, cc305 etc. May have some cam surge, depends how good the tune is.
Pass Emissions?: No, requires tuning to pass
Shift Point for Maximum Performance: 6200-6400rpm
Idle Characteristics: Choppy Idle
M6; Require Gears?: No
A4; Require Stall?: 2500+ Stall Speed

[07Softail]

I don't recognize that grind in the Gen V cam line up unless you want these specs for a custom grind which I think would yield less than optimal results. These engines breathe pretty good and can use a lot of valve lift to really boost performance.

 

RT