What's wrong with my z28?
What's wrong with my z28? Hey i had my car dyno'ed a couple months ago at Lejun Motorsports, FL. Heres the sheet:
as u can see, i had very low low end torque, it is very jagged and looks like a VTEC. The car was also spewing smoke at high rpm's. Heres a pic of that:
lol, the guy at the shop wasnt too helpful, it was a dyno day, he just said im runnign really rich up top.
My mods are in my sig, the wires and plugs and coil were done after the dyno, i also had my opti rebuilt, but i didnt notice any difference. And when im in WOT and it down shifts, and it revs up to 6k+ i see the thick smoke behind me, but it pulls nice. It also runs nice, doesnt stall or anything, doesnt shake at idle, no weird noises from engine.
What do you think may be causing the jaggedness and that dip in the dyno line? Do you think i should invesnt in a dynotune, or do you think its something with my internals?
Car had 98k miles on it when i dyno'ed it, it now has 102k
as u can see, i had very low low end torque, it is very jagged and looks like a VTEC. The car was also spewing smoke at high rpm's. Heres a pic of that:
lol, the guy at the shop wasnt too helpful, it was a dyno day, he just said im runnign really rich up top.
My mods are in my sig, the wires and plugs and coil were done after the dyno, i also had my opti rebuilt, but i didnt notice any difference. And when im in WOT and it down shifts, and it revs up to 6k+ i see the thick smoke behind me, but it pulls nice. It also runs nice, doesnt stall or anything, doesnt shake at idle, no weird noises from engine.
What do you think may be causing the jaggedness and that dip in the dyno line? Do you think i should invesnt in a dynotune, or do you think its something with my internals?
Car had 98k miles on it when i dyno'ed it, it now has 102k
Originally Posted by GREATWHITE
Double check your fuel pressure and regulator, faulty regulator would run the engine very rich down low and would cause the smoke at upper rpm's trying to "clean" itself out.
i am pretty much set on buying an OBDI cable from AKM, dynotuning is too much money for me. I want to do mail order tuning.
Launching!
Joined: Dec 2003
Posts: 246
Likes: 0
From: Texas, dont mess with us!
very jagged and looks like a VTEC
Yah, black smoke like that generally is running way too fat up top which can and will slow you down. Check your plugs and see how they are reading. Plus on that Dyno sheet. i thought i saw a Air/fuel curve and it look like it was in the low low 12s... And you dont have a turbo on your car, lol. get it tuned and youll be golden...Pay for thr tuning, youll thank me.
On The Tree
Joined: Aug 2004
Posts: 139
Likes: 0
From: greenwood ,in
you can go to your local Autozone and put a deposit on a gauge and use it then take it back for a refund, They call it their loaner program. fuel pressure is generally inthe 35-40 psi range but I have not done one of these cars personally so I may be wrong on the #'s. Test the regulator with the vacuum line on and off. with it on you should see variation with thrttle input. The fuel rail should have a schrader valve on it that the gauge would hook up to. hope this helps.
I think the headers are running you rich if the car is running fine. The a/f is 2 rich you need to back it off with ls1 edit or a maft for a quick fix. You need to check your knock and timing as well.
