Vortech Cobra feels like it's down 100hp?

viperbluelx

Sexton's Performance
Established Member
Joined
Sep 5, 2002
Messages
3,402
Location
Ringgold, GA
I bought a 98 Cobra a few weeks ago with an S-trim supercharger. The car has had this current setup literally since 1999. I replaced the old serpentine belt and did a smoke test to check it for vacuum leaks. The car makes 10psi but literally feels like it's making around 300rwhp. I didn't notice fuel pressure slightly dropping while in boost but never heard any signs of detonation and the car had no obd2 codes present. Runs and drives perfect other than feeling very weak. I took it to the track last night just to verify and it only went 82mph in the 1/8th. Any ideas where to start?
 

Deceptive

Muffin is my spirit animal
Established Member
Premium Member
Joined
Feb 10, 2011
Messages
13,445
Location
Nashville, TN
Correct but it may give you some insight. Check A/F, do a compression test, check pumps, fuel filter, gas, etc...


Sent from my iPhone using Tapatalk
 

viperbluelx

Sexton's Performance
Established Member
Joined
Sep 5, 2002
Messages
3,402
Location
Ringgold, GA
I made a 3rd gear pull and had a buddy watch the gauges. Fuel pressure raises to 50psi at full boost but then slowly falls back all the way to 40. I ordered the improved GT supercar pump and see if that helps.
 

98 Saleen Cobra

Well-Known Member
Established Member
Joined
Feb 28, 2007
Messages
19,522
Start with getting a real tune on it. they'll be able to data log and tell you more.. Running a FMU? Upgraded injectors? inline pump? Bigger in tank?

There are so many variables.
 

viperbluelx

Sexton's Performance
Established Member
Joined
Sep 5, 2002
Messages
3,402
Location
Ringgold, GA
The car was dyno tuned by Brooks Speed, it's got 42lb injectors. Fuel pump is unknown but it at one point had a T-rex that's been removed because I can see the brackets and wiring. That's why I'm going ahead with a good pump.
 

98 Saleen Cobra

Well-Known Member
Established Member
Joined
Feb 28, 2007
Messages
19,522
He's my recommendation..

Get that good pump like you're doing, maybe a BAP for it. See what size pulley is on the Vortech. Then get a retune.

If it aftercooled?
 

98 Saleen Cobra

Well-Known Member
Established Member
Joined
Feb 28, 2007
Messages
19,522
ok, so get the fuel thing figured out, and re tuned. Don't go WOT any more. Hopefully there isn't damage
 

nomoretickets

Active Member
Established Member
Joined
Mar 5, 2014
Messages
606
Location
Chicago
As other's said, i would NOT got WOT until you get the car to a reputable tuner and figure out what you are working with.
 

Users who are viewing this thread



Top