JDMC5

iTrader: (3)

Hi guys I'm looking for opinions and experience on my combo and if I would benefit from a bigger cam. My power train setup when I ran 11.92@113 w/ 1.69 60ft was:

- SBE LS1
- PRC 243's which are CNC ported with stock valves and milled .030", measured ~60.5 cc combustion chambers
~300cfm @ .600" lift.
- Stock head gasket so compression should be about 11.1:1
- 228/230 .629"/.604" 112+2 cam
- PAC 1519 beehive springs
- LS6 intake/ ported stock throttle body/ 85mm maf/ 98mm lid/ gutted air box with K&N
- 1 3/4" long tubes with 4" cutout under the passenger rear seat
- MAF tuned to lambda .85/.88 (or 12.5/13.0 in gas terms) and 29-30 degrees
- E85
- 39 lbs injectors
- under drive pulley
- Built 4L80e with 245mm triple disk ~4500 stall. I foot brake to 3300 rpm then when I floor it rpms immediately shoot up to 4000 before the car starts to move and within 4 tenths 4500rpm before the curve slope decreases according to my hpt scans. I attached a pick to show what I mean.
- Stock rear end with 3.73 gear.
- 28" mickey thompsons
- race weight was approximately 3710 lbs with me in it.
- shifts were 6600-6800 rpm

11.92@113 w/ 1.69 60ft was with the converter unlocked and from what I can tell from my scans it would run about 11.8@115 with the converter locked in 3rd. Seems a little soft especially in the MPH considering weather was really good in MI October air. The car pulls pretty good especially out of the hole but feels like it pulls pretty linear with topend that is nothing to **** your pants about.

Over the winter, so far, I've added:

- Vengence ported fast 102, NW 102, 102 lid
- 60 lbs injectors
- SD tuned
- 26X11.5" mickey thompsons on 16" rims.

I'm expecting about 11.7@117 with the new setup and I plan on adding a 9" with 4.10's which should put me at 6600rpm@118 mph and should help get my 60 ft down a little. I still feel like 11.5's are still too slow for my mods. I was thinking something more aggressive like around 236/246 .650"/.650" might be a better idea since I'm at 4500rpm right off the line and never below 5500rpm after each shift. Plus, any low end I lose should be below 4500rpm not to mention a 4.10 should make up for that anyway. What do you guys think? Thanks for the read.

Oh don't mind the a/f ratio on the scan the wideband wasn't hooked up for this run.

HCI2000SS

iTrader: (2)

You know my thoughts on this lol

JDMC5

iTrader: (3)

go big or go home? lol

HCI2000SS

iTrader: (2)

If you're going to then yes lol. That along with the 4.10 would be a potent combo IMO

madmike9396

iTrader: (29)

I wouldn't change it. That ls6 had you choked up imo.

I'd be looking at my converter if it wouldn't 60 no better than 1.69. Did you try flashing the stall ?

JDMC5

iTrader: (3)

I thought 1.69 was pretty decent considering it does 55 in 1st gear with the 4L80e, 3.73 and 28" tire. No?

Gotta remember my 3.73 acts like a 3.02 compared to a 4L60e in 1st gear.

I also feel like it will get low 1.6's with the 26" and 4.10's.

JDMC5

iTrader: (3)

I just still feel like a good H/C/I setup should pull low 11's@120 even full weight

madmike9396

iTrader: (29)

I wasn't aware that the gearing was that much different.

I bet with the intake upgrade 4.10s and a 26" tire it will run lower 11s. I bet it will go 1.5x 60 as well
What kind of power do you make ?

JDMC5

iTrader: (3)

Yes, 2.48/1.48/1.00 vs 3.06/1.63/1.00

I would need like 4.56's to leave like a 4L60e with 3.73's lol.

I have no idea what kind of power it makes, but I will know soon. I know it does 0-60 in 3.5 though, well it did at least, probably a tenth or two faster now.

BrntWS6

iTrader: (7)

1 7/8" headers

JDMC5

iTrader: (3)

I know it will gain a decent amount from the 4.10's since it will leave harder and go through the traps at 6600 instead of 6000. Just not sure how much the weight and power los of it will offset the gains ya know?

JDMC5

iTrader: (3)

I played around with that idea as well, they came out with them right after I put the 1 3/4" on.

madmike9396

iTrader: (29)

Your headers are sufficient imo. If your going 9 inch why not more gear ? 430 or 456 ?

HCI2000SS

iTrader: (2)

I agree even though the larger headers might gain a handful of hp, the current ones are sufficient enough for now, and certainly not the culprit here

Rise of the Phoenix

iTrader: (27)

The cam you have is not small by any means. I agree that the added ported FAST intake is going to help you a lot. I'd see how it performs with that change first.

kinglt-1

iTrader: (26)

The gears are not hurting much with that 4500 stall. The gears are just going to make the converter feel tighter. The stall will still flash the same rpm and net the same shift extension regardless of gear. The 26" tire will help due to less weight and rotating mass.

Imo you have added weight to the car which counter acts making more power going to a 4L80. I could see warranting such a trans upgrade in a 700whp+ car...not a H/C 346. I would look into valvetrain stability issues. What cam lobes, lifters, push rods, and valves? The Fast would definitely help. The cam looks fine but you could go bigger with that big stall.

thunderstruck507

iTrader: (18)

Seems your car runs really close to mine did with similar mods. Which is highly abnormal...usually a f body is a couple tenths and MPH quicker in the 1/4 with equal mods.

Do you have a dyno graph or have you tried other shift points? You could be overrevving it?

If not you might weigh it, could be heavier than you think.

The intake could help you a bit. I doubt a gear or bigger headers would net much gain. I would definitely agree the car is under performing a little.

kinglt-1

iTrader: (26)

in the OP it says "raceweight 3710lbs with me in it".

JDMC5

iTrader: (3)

I plan on spraying and i don't want to run out of MPH.

JDMC5

iTrader: (3)

this is under the assumption the car weighs 3500 without me in it. The car was basically stock when i bought it and they are about 3450. I will just have to weigh it then.