HoLLo

iTrader: (17)

So the story of this car: I had a 97 with an LS1 swap. Had a Patriot 225/229 .580/.590 114+4, PAC 1218 .600" lift valve springs, longtube headers into a 3" cutout. It was tuned on a Mustang Dyno and put down 359hp/346ftlb. The car was totalled due to an old lady running a red light the day after it was tuned. I then bought my SOM car. Transferred the cam, valve springs, and PCM. The tune has not been updated in the new car at all.

Mustang Dyno graph May 2009:


I have since done a few things to the SOM car. Ported throttle body, Monster Stage 2 clutch with lightweight flywheel, full 3" true duals with x-pipe. 10.5" OEWheels C5 DD replica rear wheels with a 315/35/18 Toyo drag radial. Has not been retuned since the PCM was in my old 97.

Was at Vengeance Racing for FBody Gathering cruisein and had my car dynoed. Best it rounded up was 367hp/360ftlb. I've always been told Dynojets read much higher, so it kinda got me worried if there would be something wrong with me car. Especially since it flattens at about 5500rpm. The valve springs have maybe 15k-20k miles on them, but even when fresh the first dyno flattened at around 5500, but actually made peak power just under 6200. Also on the first graph, the HP curve is still flat around 6200, where as it's already dropping on the 2nd graph. It was hot as hell in there with no cooldown, fans or anything.. What could be the deal?

Also I went to a local 1/8th mile drag strip a few nights after. I only got ONE pass it, before they closed, I got there late, so figured what the hell. I baby launched it and trapped a 9.004 @ 84mph in the 1/8. I think 85 or 86 is easily possible, I shifted early and didn't launch hard. My first time at a track with this car ever actually

Dynojet graph May 2011:


And a video of the 3 dynos.
http://www.youtube.com/watch?v=hQeTG...eature=related

spdygon

iTrader: (1)

you need a tune...my car stock just with bolt on made 356whp.
look at my sig....also i remember that car.
very nice.

HoLLo

iTrader: (17)

It was tuned at shop in TN 2 years ago on that PCM. I'm actually running a 2000 PCM that was in my old 97... But IMO, the guy could have spent more time refining the tune.. :/

Don't think i'll worry about a new tune until I get some heads. But I'm thinking maybe I'm getting valve float or something because look at 6500rpms on both graphs. Drastic difference.

JRENIGAR

iTrader: (37)

where in TN did you get it tuned???

HoLLo

iTrader: (17)

Intune Performance, Charleston, TN north of Chattanooga. I'll be taking it to KK Performance here in Little Rock, AR when I get some heads

BLINGOLE

iTrader: (5)

its in your tune man, valve float would be a drastic loss up top.

now maybe someone can chime in but isnt your waving erractic powerband up around 5200-6500 means the timings off? that being as long as the heads havent been home ported or anything.

itsslow98

iTrader: (18)

i dont see an ls6 intake anywhere in your post? if thats the case your easily giving up 20rwhp with a cam which would make the low numbers believable due to the lack of breathing ability up top. peaking at 5500rpm is weak.

JRENIGAR

iTrader: (37)

Do you have a contact # for them? Id like to take my car over there to see how the dyno #'s look somewhere other than in memphis where it was tuned.

T.Man

Not having an LS6 intake isn't helping but I would bet the cam just isn't up to snuff.

HoLLo

iTrader: (17)

I have an 01. Came with ls6 intake factory, I assumed that was common knowledge so I left it out. I have seen this cam make power above 6000 before. Patriot claims it makes power to 6200 on a stock head ls1..

Do not have a current number on me.. ill pm them to you later

JustAnotherZ

Valve Float, Fuel Delivery issue, or major timing pull due to knock.

JRENIGAR

iTrader: (37)

Looks like the AFR is a little lean. Id shoot for 12.2-12.5 range and the fact that there were no fans helping get cooler air going. Maybe you have some KR and timing being pulled due to the lean factor and hot air. Do you know how much timing it had during the pull? How about IAT's?

HoLLo

iTrader: (17)

Now that you mention fuel, I accidentally kinked my fuel line in my engine bay twice, and just mashed it with my fingers to try and open it back up. I've been looking at a stainless braided line kit for my engine bay anyway. That could very well be an issue. Knock sensors are a year old, so if there was knock it'd be a real issue, not just false knock.

No idea about timing or IATs on either pull. The 2nd pull was strictly just dyno #s, no tuning, or scanning. I know my initial tune required an open loop tune due to something with the exhaust. I've never changed the O2 sensors on my car, and I have seen a bare wire on one of my O2 wires, I may look into new extensions and O2s soon. Do O2s usually fail at once, or could they gradually decline causing problems like this?

odarabla

iTrader: (1)

Thats 1 fine *** car!!

HoLLo

iTrader: (17)

Thanks!

T.Man

Totally overlooked the year of your ride, my bad. Definitely is common knowledge.

HoLLo

iTrader: (17)

With the cam being a .580/.590 lift and my PAC 1218 single beehive valve springs rated to .600 lift, with almost 20k miles on it, it probably have some valve float huh?

litle88

iTrader: (20)

I'd say, but if you get heads I would also get another cam while your in there.

Nice car btw!

HoLLo

iTrader: (17)

Thanks! and trust me this cam WILL be coming out for a custom one when i get some heads. Lookin for a low 230s duration low .600-.610s lift on a 112

HoLLo

iTrader: (17)

Could bad O2 sensors/wires cause this lack of power climb above 5500? What about if my fuel line in the engine bay was slightly pinched?