Stoney667

iTrader: (3)

Finally got my cutlass dyno'd. Not sure what to think of the results. Not 100% happy. My tuner couldn't be there but I do have hp tuners i'm just not that good with it. I was able to add timing. Didn't mess with the fuel mixtures. I was getting 12.8-13.2 A/F I know its a little lean.

Setup

LQ4 block w/ Katech Rod Bolts
CAM
Intake Duration: 234 Degrees at .050" Tappet Lift.
Intake Lift: .602" with 1.7 rockers.
Exhaust Duration 246 Degrees at .050" Tappet Lift
Exhaust Lift .607" with 1.7 rockers.
111 Degree LSA
243's milled .006 for cleanup
LS9 Head Gaskets
LS6 Intake
P&P LS1 TB
G-Body Swap Headers
Full 3" exhaust

Built TH350 w/ 3.73's

Graph is attached. Max was 361whp. I'll get the TQ #'s tomorrow. IIRC they were 375-380.

What my main question is is why is it losing 100hp on the top end?

http://i311.photobucket.com/albums/k...611_143217.jpg

MikeG

iTrader: (33)

No RPM pickup? How high did you rev it? I don't think the numbers are that bad, considering the tune could be better and the inefficient drivetrain. What makes you think it's losing 100 hp?

Stoney667

iTrader: (3)

Not really a loss but most dyno graphs go up at the end until it stops making power, so its like after 6k i'm not making any more power and i'm not sure why i guess is my question.

Sorry was running it out to 7k

I should get the graphs tomorrow, didn't have a flash drive to get them off so just have my picture.

Link to Video, hopefully it works

http://www.facebook.com/photo.php?v=...e=2&permPage=1

MikeG

iTrader: (33)

What stall speed is the converter? Looks REALLY loose.

Stoney667

iTrader: (3)

its a PTC 4500 stall

1989GTA

That does not look like a dyno friendly converter to me unless it was locked up.

itsslow98

iTrader: (18)

How are the swap headers as far as flow? I made 417/390 through a 6 speed in my mustang with that cam. Mods are in my sig, stock untouched 241s, ls6 intake, untouched TB, kooks long tubes, UDP.

Im guessing the auto and stall is killing it. How does it feel on the road?

streetknight2

iTrader: (10)

1- That converter is not gonna give dyno queen #'s for sure, BUT it ought to run good at the track is what I'd be worried about anyways

2- If that's a stock bottom end LQ4, you only have around 9.5:1 compression. My friend just popped his LS1 and bought a LQ4 and put his heads and cam in it, the car lost 63 RWHP with the 6.0 cause of the loss of compression.

Stoney667

iTrader: (3)

On the street it feels like a monster, we raced an R6 the other night in it only had a bike length on me from a 40 roll when we shut down @ 120 ish. Not sure on his riding skill i don't think it was the greatest but from a roll was pretty impressed. That was before the dyno and gaining the extra 15hp.

I'm guessing its the stall and auto as well thats what a lot of people have been telling me. It slams that converter on the hit on the street and pulls really good. Also have the trans brake.

Its a stock bottom end LQ4 but it does have the 243's that are milled .006. I think IIRC its like 10.2:1 from reading other posts.

I mean if i'm getting a 20% loss through the TH350 and converter. 20% of of 361 is 72. Which comes out to 433. So through a 6spd it would probably be about where I thought.

itsslow do you have a dyno graph I can look at to see how your curve looked at.

I'm just still not understanding why after 6k it falls so hard. What does everyone think about the 12.8-13.2 A/F should I add some fuel? I know I need to tweak my curve a little I like the 12.8 better than the 13.2.

maxpower_454

iTrader: (7)

IMO you should take it to a professional tuner. That way you won't be on the edge with A/F ratios and they can also probably tell you where - if anywhere - you're losing power.

MikeG

iTrader: (33)

I'd say its making closer to 450. 20% loss off of 450 is 360. Just shift it at 62-6300 and let er eat.

thunderstruck507

iTrader: (18)

Your numbers seem to be within normal for the compression and converter and everything, especially if the tune isn't spot on.

Not sure what you mean by losing 100hp...that is not a 460rwhp set up in any situation. Even in a manual trans car on an average dyno I would be shocked to see over 420rwhp.

Stoney667

iTrader: (3)

My tuner is a professional tuner. He just couldn't be there for the dyno. I live in Lima and the school UNOH is there and I have friends that go there and they got me on the dyno.

By losing 100hp i mean after we hit peak power by 7k i'm down over 100hp from the peak. I just expected it to keep pulling and not fall off over 100hp.

KC Henry

That is the exact same cam I have in my LQ9, and it didn't dyno much more, but the kind of 1/4 mile ET's these Cams produce leads one to think they are making much more power.

Stoney667

iTrader: (3)

KC what does your car weigh?

KC Henry

Just a touch over 2 tons with me in it.

MikeG

iTrader: (33)

Damn, I go to UNOH. I would have liked to check your car out! When did you dyno it? Monday?

masnart2000

The numbers seems a little low to me for an LQ4.

Stoney667

iTrader: (3)

KC you went 12.0 weighing like 4400lbs? I weighed the cutlass in at 3480 with me in it. I suspect it'll run 11's. How deep I don't know.

Mike we dyno'd it Monday around 2pm. I have the car out at orielys on the weekends. I won't be out for a couple weekend though.

KC Henry

My 12.0 was using basically only 2nd and 3rd gear, (1st gear wasn't working really, you can hear it in the video of the 12.0 pass), and I also left off the foot brake since the rearend won't stay together long enough to leave off the 4500 stall (where it would be most use of the engines power band).

11's will be no problem for a light car like yours.