Chris Edwards

Thanks to CMS for their thorough dyno time today.

471/442

LS2 untouched shortblock purchased from forum member, unknown mileage but looked like less than 10k
TEA 2.5 243, turned down hollow stem LS3 valves, BTR springs, ti retainers, milled to 64cc
Fel Pro .041 headgasket
static compression 11.5:1, DCR 8.9:1
BTR stage 2 cam, 227/234, .614/.576, 113+3
Cloyes hex-adjust timing gears / chain
Melling medium volume oil pump, blueprinted
Johnson short travel lifters
BTR pushrods
Comp trunion kit
Fast 92 port matched
Ported LS2 tb
K&N intake
LG 1 3/4
stock ti catback
Mobil 1 0/40
LS7 clutch + Fidanza
ATI 10% pulley
GM 36lb injectors, rebuilt/ flowed
Walbro / Lingenfelter pump

LSOHOLIC

Nice......great power for that sized cam. And with that 43* IVC and no flycut, I bet the dynamic compression is stout. Did you guys see any knock while tuning it ??


.

Chris Edwards

I believe he did see knock initially.

On another note, I am experiencing what I think is a lazy/ uncrisp off idle or in between shift throttle condition. It feels like there's play in the accelerator pump linkage, for the carb guys. I've read that both a stock ls2 tb or improperly ported ls2 tb could cause this.

Chris Edwards

The calcs I used to figure out DCR came up with 8.9:1

blackdak318

Great numbers. As you know I have pretty much the exact same set up but on a 346. I made 448/398 but on a pretty stingy mustang dyno. Congrats! I would be very happy with those results. Where the heck did you find a set of TEA stage 2.5s? What size valves?

Rob Petyo

Nice numbers!

any plans to track it?

Chris Edwards

Thanks I used your build as my inspiration, with a few changes such as the short travels and a bit more compression. I haven't heard many cammed LS cars in person but the valvetrain is damn quiet. I was hoping it would be given the expense of the Johnson's.

I had TEA build them for me out of craigslist cores. Turned down LS3 valves per their recommendation.

Is it kosher to ask a dyno shop what their correction factor is? I do know that the numbers are SAE corrected, CMS confirmed that. Seems pretty much every LS build in Southern California uses their dyno.

I do have plans to track it once or twice before it gets hot. I have a set of old R6s that I mounted since my street tires were bald and they seem to hook pretty good when aired down to 20 or so. I didn't build it as a 1/4 mile car, otherwise i would have put a gear in it and made a bunch of other changes. I just plan on dd'ing and doing corvette challenge events once I put an oil cooler on it.

Chris Edwards

These numbers were also on CMS's Mustang dyno.

JohnMatt

Turned down LS3 valves? Never heard of that before

LSOHOLIC

Economical way to run a lighter weight valve, when running over sized valves.

And has been proven to make a hp/ET difference on a "max effort" style build.

robz

Great numbers for 243 heads.

Chris Edwards

A turned down LS3 intake valve @ 2.055" weighs 85 grams (untouched LS3 valve weighs 88 grams). That's close to the weight of a titanium valve in a comparable size.

So the turned down LS3 valves offer the opportunity to install a larger valve (than LS6's 2.00") on a 243 head while being extremely lightweight, and at a very reasonable cost.

FWIW, here are my TEA flow numbers:

Lift Intake CFM Exhaust CFM
.1000 69.6 61.5
.2000 146.5 124.8
.3000 212.6 180.0
.4000 260.5 224.9
.5000 300.0 249.7
.5500 313.8 255.9
.6000 322.1 259.0

These TEA 2.5 heads outflow an AFR 215cc and they are neck and neck with an AFR 230cc when tested on a 3.900" bore... TEA's flow sheet did not indicate what bore size the flowtest was done on.

The price is somewhat similar to the cost of AFR's. I have never weighed a set of AFR or TFS, but I did weigh a pair of ETP 215's and the ETP's were 25lbs heavier than my TEA's (both sets were assembled).

My choice in heads came from considerable research, cost was not the primary factor, although the TEA's ended up being a couple hundred bux cheaper in the end than an off-the-shelf TFS/ AFR. I really liked the fact that the CNC 243's would keep ~25lbs off the nose (my car will never see boost so the 3/4" thick deck on the aftermarket heads was not a concern), and that I could use factory rocker arms (yes, AFR's also use factory rocker arms) but I would have had to invest a lot more money into the AFR's to get anywhere near as light of a valvetrain as I did with these TEA's...

Chris Edwards

Took the car to Famoso today just for kicks, ran a bunch of 11.60s - 11.70s @ 121-123 mph. 1.90 60ft was my best of the day, not surprised as the only tires I had were dried / worn out/ heat cycled Hooser R6 road race tires that I aired down to 18psi hot. DA was 1500ft. I was getting some pinging at top track, so I bought a 32oz bottle of Torco from the fuel man and pinging went away but it got a lot warmer and I only made 1 pass with the Torco (mixed with half tank of 91). The Torco did raise mph by 1.2 compared to previous pass, even though it was hotter out. So I think with cooler air and Torco or a few gal's of 100 octane in the tank, the car might mph 125, but not much more than that. I still have the stock tstat in the car, so it was running at ~210* all day. I wonder if that's contributing to the pinging? I've never once heard pinging on the street. I was hoping it would mph higher, but on the way home the car felt TONS stronger with the Torco in the tank, literally night and day. The motor has a more aggressive sound at WOT and feels like it has more low end. Either way, I didn't build it to be a 1/4 mile car, so 11.67 @ 123 is acceptable to me, given the tires.

Chris Edwards

I put the car on A&A's dynojet today, made 477rwhp/444rwtq SAE, 489/455 non SAE. I do have an injector issue of some sort, I've known it for a while, as one time when I primed the pump (motor and fuel cold) with the rail raised, there was a little squirt from one of them. The motor also doesn't "chop" at idle like it should, it almost sounds like it has a miss but new plugs, 2 new sets of wires, and a spare set of coil packs did not fix the issue. Really strange though as I sent the injectors out for cleaning and leak testing and they came back fine. I've ordered new flowmatched Bosch 36lb replacements from 5.0Motorsports that will be here tomorrow. Heading to the track up north near Sacramento for good air on Friday to try and get as close to 10.99 as possible. Fingers crossed I don't break an axle or other part 10 hours from home. On a side note, Andy @ A&A runs a very impressive operation and I'm amazed that he has that many things going on. Mail order, a half dozen vettes being worked on at once and another dozen in the lot waiting, mail order, his supercharger kits being assembled, and he is still answering the phone while on the dyno and totally willing to shoot the ****. There's no way I could be that friendly will all that going on LOL.

luke87gt

Congrats on the numbers Chris, and best of luck on Saturday in Sac.

lol, yes, people who can balance all that and still be customer service friendly are the lucky few

robz

Nice going!

robz

Try and borrow a set of drag radials if possible. Goodluck.

Chris Edwards

I purchased a new set of Hoosier drag radials 315/35/17 so that is what I will be driving to the track on, airing down, and making runs on.

Any tips on air pressures and launch techniques with these Hoosiers? I was planning on airing down to 18psi, 4-5 second burnout, then sidestepping the clutch at 4500.

luke87gt

Yes, 18psi, burnout till you see smoke, and side step clutch at 7,000 RPM. It would be wise to follow this procedure.

LSOHOLIC

Haha.....make sure to get the "sidestep" on video....

On a serious note, where are you shifting this setup ??


.