mrvedit

I'm currently running CNC ported 243 heads on my LS2 with LS6 intake, a 231/237 cam with 0.610 lift, new LS7 lifers, and dual valve springs with Titanium retainers. Shifting at 7000 rpm gives me the best ET; .25 better than shifting at 6500. The car is mostly a daily street driver; its an '81 Camaro with the swapped LS2 and 4L65E.

Now, I'm considering switching to L92 heads, but am not sure of the benefits, even after reading hundreds of threads here.

I get the feeling that CNC ported 243 heads flow very similar to stock L92, but of course L92 can be ported too. I have read that L92 have heavier valves and are designed for <= 6000 rpm, in which case my cam is not suitable. Or perhaps that is hogwash and it just depends upon the valve springs; I would definitely need higher lift valve springs in any case.

My next experiment (after Michigan winter) is to try a FAST intake and/or a 4150 style EFI setup. Since these manifolds come in LS1 or LS3 style, I need to decide which heads to run.

So, what do you suggest? Is the cost of switching to L92 heads worth it (heads, valve springs, rockers, etc)? And will it work with my current cam? Or would I need to go all out with ported L92, custom valves and springs to see much benefit?
(Or send me links to similar threads.)

Thank you!

COPO9560

Changing the heads really depends on your end goals. While a set of ported L92 heads, with a new cam, may make more power, they really would run better with more displacement, driving your costs up further. If you have a good running combination now and want a little more power, put a 125 shot of N2O on it - a lot less work and more power anyway.

Their are a couple different carb style intakes - open plenum will cost you some low end, not always what you want for a street car. At least you have the option on your car without getting saw out.

mrvedit

Yes, I'm also thinking now that the heads are not my "weakest link". I was just tempted by some new L92 heads for $575 in Detroit. (There are some low prices for parts in Michigan.)
I think my weakest link is the air intake - you can see the pseudo box I made in my picture above. It is very difficult to build a good cold air intake on a 2nd gen Camaro. Since I have a raised hood for air intake off the windshield, and already have a 4150 style EFI throttle body, I may give a 4150 intake a try. I do experiment all the time. However I have no plans to ever try N2O; I would install a supercharger first.

Thanks COPO. I certainly am open to more opinions and suggestions too.

SOMbitch

iTrader: (8)

Off subject but that is a badass looking 2nd gen dude....

midevil1

iTrader: (17)

X2..Most that I see down south are HOOOOOPTIE"S!! Your's is VERY NICE!

Jimbo1367

X3. Sweet looking car dude. Any build threads? Whatt was your first impression on your first ride after the swap? Very clean swap.

Jim

mrvedit

Thanks for the kind words. I was very fortunate to find a California show car for sale in Michigan. (I checked Carfax to confirm it.) Car is just as clean underneath, never been in snow, rarely even in rain. The previous owner got tired of shows, hot rodden it with a 383 and then had to sell it. Shortly after installing a Holley EFI in it a split crank destroyed the engine:
http://www.nastyz28.com/forum/showthread.php?t=196932

I had already bought the LS2 by then and immediately started the swap. Sorry, but I have not yet created a build thread. I mostly just help others on the NastyZ28 forum with pictures to show specific solutions.

My very first ride wasn't good because the transmission went into limp mode. It was a brand new 2010 4L65E trans, which due to significant changes GM made in 2009, was incompatible with my PCM. I described that here:
https://ls1tech.com/forums/automatic...-solenoid.html

I had to get an old junked 4L60e and "merge" its valve body onto my new 4L65E, while also installing the TransGo shift kit. Sure learned a lot about 4L60E trans in the process. My winter project is to rebuild a couple of junked 4L60E "just for fun"; already ordered a bunch of trans tools for it.

82cetuner

iTrader: (9)

you need a set of heads with hollow stem valves and good springs to hit 7k with ls3/l92 style heads.

for a comparrison the 418 I have has cnc ported ls3 heads that flow about 350cfm at 600 I belive and my engine can hit 7k rpms but I do have a harland sharp trunion upgrade, morel link bar shifters and hollow intake valves as well as better springs

IRONFIST

I'd really like to see what went into putting that engine in there. I wish I had gone that route. Anyway, as for the topic, I'd agree your intake is a bigger restriction then your heads. If you can get the heads cheap, have them worked over and cn afford a better intake set up... That's what I'd do.

parks450

iTrader: (17)

Agreed a FAST 102 would benefit you now since you have cnc'd heads. That their would bolt on 15+ hp easily and pull alot harder than the ls2. I really dont think you would benefit a whole lot with l92's etc. Like stated add a 150 shot and a 102 .

mrvedit

Thanks everyone for the feedback.
I'll stay with my 243 heads and try both a 4150 intake and a FAST intake next year (after the darn Michigan winter).

Jimbo1367

mrvedit
Who CNC'd your 243s? any curtain Level?

thanks,
Jim

mrvedit

I don't know that; I bought the engine from someone in the Detroit area who appeared to be well connected to GM engineers. The intake ports look like this:



However, the LS6 intake manifold was not ported to match; not sure if that is even useful.

camarozz383

iTrader: (3)

that car is awesome looking! I love it and wants another one.

lemons12

iTrader: (71)

A stock l92 top end won't make much if any power above 6-6200 from what i see.

Footlead

iTrader: (18)

Love That Car !!!!!!!!!!!!!!!

Jimbo1367

This ride reminds me of my old 80 Z28. Mine was white but with the gold stripes/interior. I always wanted to get another one and do a LSx/A4 with chrome 18" IROC replicas with the matching gold stripe in the spokes. I can always pipe dream.

Mrvedit,
do you have any standing excel. videos?

thanks,
Jim

BODUKE

I've seen that car up close and in person and it is indeed very beautiful.

low2001gmc

iTrader: (148)

i love my lq9 with "me" exhaust only ported ls3 heads (ti retainers and psi1511 springs) and a 232-238 cam. wont back to 243s on my budget. now i do have an ls2 portworks ported l92 intake which stock is better than ls3 intake. if sticking to a car intake, i would just put a fast on it i suppose.

mrvedit

I see this thread has been resurrected.
Last year I changed to a 4150-style EFI intake with a GM-compatible Throttle body. This lets me me use a retro-style 14" air filter and the "air injection" off the windshield and through the hood. It looks like this:



And with the air cleaner off:



This change boosted my speed by 3 mph (to 117) and lowered by ET by .2 sec.

It's fun at the track with the hood up because people look/stare and cannot figure out what it is.

I have since learned that Livernois Motorsports in Dearborn MI ported the heads. I'm confident I can get 119 mph and 11.5 ET out of it soon.

Sorry, I don't have any videos of the car. I do have this picture of the inside: