gtodoug

iTrader: (1)

Well I've been dialing in the setup on the street when I can with my hectic work schedule. For those of you who don't know the setup it's a:

LME 408ci
11.94:1 comp
254/260 .660/.643 114 LSA cam
Kooks 1 7/8" headers
Corsa single 3" exhaust
ET 245cc heads

This tune is on 93octane pump gas. So far I'm only able to run a max of 17* of timing on the street. I attribute part of that to the CR and 93 octane and the other part to the poor exhaust I'm running. I dropped the exhaust on the dyno and it was worth 18whp and 22lb ft of tq! So needless to say my SW dual 3" is in transit. I didn't want to run cutouts, so a full exhaust is in the works. The pulls below are with the exhaust attached and with about 500 miles on the motor.

The car is tuned in open loop SD using HP tuners 1bar SD software. These pulls were made through my single driveshaft/3.91 gears/ and 18" wheels and tires as well. I left the a/f very conservative at 12.1 down low and 12.6 up top. Should be some more power left in there of leaning it out as well. I think that's why the tq is so weak down low. I'll get it squared away though.

I've got a couple tricks up my sleeve yet, hence why I'm calling it the "preliminary results"

Here is the very first/last pull after some timing/fuel tweaking.


Video of car on the dyno:
http://media.putfile.com/408-dyno-pull

Phil99vette

iTrader: (11)

interesting...sent PM

Patrick G

iTrader: (14)

For preliminary dyno numbers, they're pretty darn strong. Hopefully with more exhaust development and further tuning, you'll have the numbers up there with your earlier power predictions. Gotta love these cars!

bad95killer

Damn stout #'s buddy considering ya running 12.1 to 12.6 A/F ratio more tweaking to ensure the 550rwhp

Congrats man

peace

Orange Peel

iTrader: (20)

NICE numbers dude! I'm hoping for 500rwhp with my Combination Motorsports 402, that's got to be a blast to drive, tons of torque down low, poor tires

ls1408cp

iTrader: (37)

is 530 with the exhaust dropped

LSs1Power

iTrader: (5)

Very nice.

cantdrv65

iTrader: (3)

Excellent numbers for the tune being as off as it appears....

gtodoug

iTrader: (1)

No 530 is not with the exhaust dropped

gtodoug

iTrader: (1)

I think the tq is way low in comparison to what I've seen some other 408's put down. I was hoping to hit that 515-525rwtq mark. After the first pull, I realized that was a pipe dream.

dougie

11 Bravo

iTrader: (3)

Not bad. If the ET heads are everything they claim to be, you should have alot more left in it. How is that cam on the street, BTW?

niphilli

What intake manifold?

Patrick G

iTrader: (14)

Yeah, the standard for good torque under the curve seems to be 1.25 lb ft of rear wheel torque per cubic inch. 510 would be that number on a 408. Anything above that is just outstanding. Once you get the exhaust and tune sorted, I would expect to see the mid-range torque pick up some although I feel that your cam is mis-matched for your combo. The same cam on a 108 or 110LSA would give you MUCH more area under the curve. You appear to have a classic case of low dynamic compression and too late of an intake valve closing point for your combo (FAST 90/90).

prostock_bigblock

iTrader: (11)

why 114 LSA?

gtodoug

iTrader: (1)

I don't know. I tried to keep it streetable and was afraid that the cam would be too much for the street. EDC made the cam. I kept stressing to him I wanted the cam to be driveable. It's more driveable than you think now, but is very very loud. Maybe i'll switch down the road.

Dougie

beardWS6

iTrader: (1)

Nice GTO! I was hoping for differant numbers also. But this ****** runs its AS-off!! Will be at the track in 2 weeks. Then will see what shes got!! Great numbers!!!

gtodoug

iTrader: (1)

Patrick, when I initially had this cam ground. I had spec'd out a different set of heads, was using 2.5" duals, and my entire setup changed due to me having too much time on my damn hands. I built the setup around the motor and heads and stuck the cam in that I had ED spec out before I had the motor built.

kumar75150

Honestly, this makes me want to hold of on purchasing ETs for now. I know you will probably pick up more power but I thought 550 would be a breeze with a big cam.

Either way 530-540 is gonna run its *** off. Im anxious to see what mine will make with LS6 heads and the new cam.

gtodoug

iTrader: (1)

Well, next mod for me is a possible cam change, and ITB(individual throttle body) manifold from Harrop. If it really adds that much hp. I just want someone else to go first.

Keep in mind guys I'm not running much timing in this setup either. My timing map looks like this:
2800-17*
3200-17*
3600-17*
4000-16.5*
4400-16.5*
4800-16.5*
5200-15.5*
5600-14.5*
6000-15.0*
6400-15.0*

Anything more than that, I get some KR induced. Not much, but .1-.2*. So I backed off a couple * to aid in fighting the detonation. I'm going to try some torco and see if it makes a difference.

dougie

kumar75150

with that big a cam, im surprised you are getting knock at 11.9:1 compression

doesnt sound right