hey all. i just bought a '00 z28 2 weeks ago.
only mods are loudmouth exhaust and ls1motorsports lid, k&n filter.

dyno runs

question..... am i running to lean??? the car sorta feels like its bogging down just slightly inbetween 3.5-4k rpm. spark nockin too. its not throwin any codes on the tech II however.

thanks
mike

 

Hope I see similar numbers when I get my exhaust.

 

ttt

 

That's really lean for the mods u have, that's kinda strange....

 

yea..its pissin me off to cuz i dont know what the funk is causing it to run so lean.

 

hmmm... any computer mods? i ask cause most A/F readings on mostly stock cars show the cars ratio dropping hard into the 12's but yours stays at like 14-15 the whole time..

Make sure you dont have the IAT mod or any other thing that can throw off your air readings then you can see if its fuel related or what...


the knocking could be an issue as well..

Did they mention anything at the shop where you had the runs done?

 

yea..one of the guys was surprised it stayed around 15...even he said it should be around 12...12.5. he suggested either adjustable fuel pressure regulators or the new predator tuning computer to correct it... meanwhile.......im still like........WHy is it running this lean in the 1st place????? no mods other than the exhaust and intake lid. grrrrrrr.

 

Ok, I had about the same a/f ratio before I got the predator. I also have ported maf ends, but anyways, when I got the predator the performance tune lowered my af ratio to 13.0/1 from 5000 rpms on and decreased it quite a abit, like around 14.0/1 at lower rpms, from 3,000-4500.

BTW, if you want, click on the link to the pics of my car, there's also a pic of my dyno sheet which shows how I dynoed before hte predator tune and after.

 

Mike,
Hey dude. I see your from Charlotte...
I am from the Belmont/Mt Holly area.
Did you go to the Werx dyno on Harris Blvd? Shoot me a complete list of the mods that you have done, also does the car look like its been modded in any way. If it had the stock muffler on it then I would say no. I can help you trouble shoot it if you want.

Later
Mike

 

Running way too lean,go get a tune.

 

306/327 with a lid and LM, eh?

I wonder wht I'm going to get with my cutout and lid since my stock was already 297/309...

Hmmm... I would assume I'd get more then 10hp out of my mods... We'll see.

TS

 

hey man...
im 5mins away from mt.holly.... off my holly/huntersville rd.

anyway....no other mods. the guy who owned it before me just put the catback and lid on. only replaced the water pump under warrenty.....and changed the spark plugs out himself. i dont know why he changed out the plugs... originals are good for 100k.
i went to a underground racing off of tyvola rd to have it dynoed. nice facility there. had 2 blown vipers. pretty impressive. 3 runs for 60 bucks.
grrrrrrrrr........why is my car funked up?!?1!/

 

First maybe check one of the front (easy to get to) plugs to make sure he put in the correct heat range. Second we may need to throw a tech II on there and get a vital signs of the car going down the 1/8th mile.

Ive got a close friend that lives out near Hornets nest park. His name is Thomas Hawkins and he drives a 93 Dark Green TA with Chrome Vette wheels. The car has a 383 that pounds the ground.
You may know him or have seen his car.

We are headed to Mooresville tomorrow night to get in a few runs ...practicing for Darlington on the 8th.

Why dont you make the trip up to Big M and let me and the guys see what the problem is ?
It would be cool to meet you and hang out a little too.

Let me know

 

i'll see if i can make it up. its the g/f's birthday tomorrow...she might force me to take her out. haha....but i might come up for a little while anyway. i havent been up 2 mooresville track in a few mo. i'll send u a pm.

later

 

I had almost the exact same numbers as you. With no mods i put down 294/296..... With my SLP lid and 3" cut out I put down 320hp and 330tq. Thats a 26hp and 34tq increase....not bad for a lid and cut out....