jlangley

iTrader: (8)

I am assembling an LS2 to install in my 01 SS and am looking for some input/confirmation that I'm on the right track. First LS build but I've been researching a lot. I'm trying to do a good quality job while being budget conscious. I've purchased most of the parts from individuals here as deals came up. Some parts are new some used.

Here's what I've got so far:

LS2 shortblock from an 06 vette
BTr Stg 2 LS1/2 cam 227/234 113+2
Johnson 2110 lifters
Cloyes hex-adjust timing set
CNC ported 799 heads - A.I. 226 w/61.5 cc chambers
BTR .660 dual springs w/ ti retainers
Fast 92 intake and WARR TB
Improved racing crank scraper kit
Meziere electric wp
ATI 10% ud dampener
Mighty Mouse catch can-
stock LS2 valley, front and rear covers
complete felpro gaskets w/ stock replacement head gaskets
I also have the felpro performance head gaskets @.041 thickness

The car and drivetrain is stock except for Kooks 1-7/8" lt's & ory, Yank SS3600 converter. So 3:23 torsen 10 bolt.

I don't have a hard number/goal in mind. I just want to have a fun car to drive. It's a weekend toy/cruiser, car shows, sport touring the backroads. I want to keep driveability near stock levels but have a noticeable performance idle with a significant improvement in overall power.

I am concerned that the compression may be too high. I calculated the static cr @ 11.82-1 and dynamic @ 9.04-1 using the .041 gaskets. I generally run at least 93 octane fuel. It would be nice to be able to use some 91 in a pinch though.

Open to any thoughts, input, suggestion you may have.

grubinski

Agree on the compression. It would be less of a headache to drop it a touch. Just IMHO. The rest of it looks a lot like the motor I'm putting together right now, which is also intended for good street driveability.

gnx7

iTrader: (28)

Keep the compression and put in a 1/3 of a bottle of

Torco F500010TE Unleaded Fuel Accelerator with 93 octane for good measure. You can find it on Amazon.

93 octane USA rating may be different than Canada.... 93 octane fuel in the USA easily supports 12:1 compression. I ran 11.25:1 compression with 91 octane in lots of engines here in California and set them up for 12:1 in areas that get 93.

Save up money for a new rear end.... you are going to need one soon

Launch

Everything looks good, but with that cam if it were me I'd just run the 0.051" thick factory gm mls head gaskets which should bring CR down to 11.5 and make it a bit safer on 93 and occasional 91 octane. The roughly .3 CR extra with the .041 gaskets isn't going to gain you much especially with a cam under 240's duration, and risk having to back off timing which will just result on you being down on power. Plus I always prefer to use the factory gm head gaskets. I really don't think the 0.010 in quench is going to be of any benefit because factory ls2 pistons are already around 0.008 out the hole.. so with 0.051 or 0.052 gm gaskets your quench is already only 0.044".

jlangley

iTrader: (8)

I did look into the octane rating and it is supposed to be the same here as the U.S. I'm thinking about a rear... and an upgraded trans too.

jlangley

iTrader: (8)

Thanks for the input. I was thinking the thinner gasket would be an advantage in avoiding detonation by improving quench. I wasn't thinking to run it to deliberately raise the cr.

G Atsma

It's a balancing act. Thin gasket plays with octane requirement vs. quench vs detonation. It MIGHT detonate, or not, depending if the better quench clearance allows the quench to offset detonation.

bortous

Great cam specs for intended use.

jlangley

iTrader: (8)

Is 11.8-1 with .041 gasket more or less likely to have a detonation issue than 11.5-1 with a .051 gasket?
I suspect there is little difference tbh.

I still have to check ptv clearance, might be a factor.

zzracer

iTrader: (33)

Check your Piston to valve clearance good with the heads milled and thin gaskets . Should run good. My heads are 61 cc and I'm running stock .051 gaskets. I'm a little more max effort than you but yours will run good and you want be disappointed in my opinion!

jlangley

iTrader: (8)

Setup the cam timing today and checked piston to valve clearance. Used .051 thick shims in place of head gasket for measuring purposes. Intake seems pretty tight at .074, exhaust was .144.

I used the dial indicator method to measure.

I guess the .041 gasket is definitely out.

Would you run it at .074 on the intake?

Che70velle

iTrader: (6)

Man...you want to see .080 minimum. What kind of rpm are you gonna turn?

jlangley

iTrader: (8)

I'm not sure what rpm I'll run it up to. It's not max effort by any means, might take it to the strip to see what it runs but that would not be a regular occurrence. Pretty much all street cruising'

Maybe 6500 +/-?

Che70velle

iTrader: (6)

Ugh...if it was mine, I’d flycut .025, run the thinner gaskets, and run the slop out of it.

jlangley

iTrader: (8)

Sounds like a solid plan. Time to research fly-cutting I guess.

zzracer

iTrader: (33)

Check out the Lindy fly cutters you use in the head. That's what I used. My heads are cut .030 and I had to cut .100 cuts even with a .051 gaskets. They work good.

jlangley

iTrader: (8)

I am looking at those. I guess since I've got a 2.00" valve I need a 2.10" cutter?

Still have yours? Want to make a deal?

zzracer

iTrader: (33)

I would get the one the same size of your valve. Mine are bigger.

Che70velle

iTrader: (6)

I use these as well. Very nicely built and easy to use. When you call to order the cutter, the size you need will be determined by the valves you have in your heads. The cutter must be a little bigger than the valve for radial clearance.

Know It All

Did you measure that with checking springs? I would be okay with .074" but if it makes you feel better, the real springs will cause a little bit of deflection and increase that PTV.

Don't forget that you do have an adjustable timing set. You could always retard the cam a degree to give up a little exhaust PTV to gain some intake PTV.