Sounds like I'm stuck with a thousand dollars worth of useless parts... LMR.com won't let me return them because they were installed. Even though the parts described as "NO TUNE REQUIRED"... Which is a lie
Help a newbie... bolt-ons ruined my car!!
- Thread starter Bl00dtrail
- Start date
I think you need to take a deep breath and some research to understand whats going on a little better.
To the best of my understanding you ordered a bunch of no tune required parts AND put on a performance tune that wasn't written with those parts in mind. Most cars tend to run a little rich and conservative timing from the factory so minor air flow mods might lean it out a tad but over its still safe. Now you added a tune for a stock car that was designed to lean it out and add some timing, problem is the car was probably leaner than the tuner would have anticipated due to the other mods.
If you had detonation you might have nuked some spark plugs and even going back to stock it doesnt run right because you've smoked the plugs.
edit: not sure where you are on the coil but Id go oem as recommended. In the meantime I would put fresh plugs gapped as recommended earlier to rule that out. Put it all back to stock, get the TPS back to the correct position which is a pain in the ass and requires minute changes to get it right. Personally Id probably unplug the battery at that point for a few minutes, turn on the headlights to completely drain anything left in the system. This way you're basically starting over fresh
To the best of my understanding you ordered a bunch of no tune required parts AND put on a performance tune that wasn't written with those parts in mind. Most cars tend to run a little rich and conservative timing from the factory so minor air flow mods might lean it out a tad but over its still safe. Now you added a tune for a stock car that was designed to lean it out and add some timing, problem is the car was probably leaner than the tuner would have anticipated due to the other mods.
If you had detonation you might have nuked some spark plugs and even going back to stock it doesnt run right because you've smoked the plugs.
edit: not sure where you are on the coil but Id go oem as recommended. In the meantime I would put fresh plugs gapped as recommended earlier to rule that out. Put it all back to stock, get the TPS back to the correct position which is a pain in the ass and requires minute changes to get it right. Personally Id probably unplug the battery at that point for a few minutes, turn on the headlights to completely drain anything left in the system. This way you're basically starting over fresh
I immediately flashed the chip back to stock settings... and then systematically removed the mods one by one and trying to get it right until its 100% back to how it was when I bought it.
Runs ok now...
And yes I agree there was too much air making it lean... and Idont know enough to balance it out and make those aftermarket parts work together without a professional tune. Thanks
Good to hear it is running better.
Once you double check spark plugs, Then you should be ok to put on cai for now.
Keep the TB somewhere you can see it, to remind you to be careful..lol
far as the tuner, keep it around, its handy to have for code reading and little stuff like tire size if you do it before full custom tune
you typically cannot make enough adjustments through the handheld on your own, you need the actual tuning software for a laptop to create a new tune which would then be loaded into the tuning device and then into the car. Your car is extremely basic, get it running correctly bone stock then have someone email you a tune for the mods you have. As others have mentioned I would avoid the TB, theyre far more trouble than theyre worth. If you go with a PD blower you'll get a different one anyway and if you go centri blowing through the stock piece is fine
Unless the stock TB is a restriction which it isn't on these cars I wouldn't change it. You could probably stick the stock TB back on and then use the cai and tune and it will run fine. Return the TB if you can and put it towards something that will help the engine breathe like exhaust if you don't have that already.
Read through this thread. You installed a bunch of mods, and then a canned tune which is NEVER a good idea, then you have no wideband which is double bad for any car with a tune... I know you are new but... eh... you are new. LMR and others should never sell these parts with "no tune required" because someone in your shoes can have this happen.
1 - Put everything back to OEM including any ignition stuff
2 - Get change your spark plugs
3 - Install a wideband, bug it into your SCT device (if you don't have one get a X3 or X4)
4 - Get ahold of a legit remote tuner to look at datalogs and then tune your car with the stock parts. Sell the parts you bought on the classifieds here or CL or wherever. That cold air and TB are going to make 0 power difference over the stock airbox and TB on a 98 Cobra.
If you are going to mod this Cobra... 4.10 gears, midpipe and catback and then work the suspension as much as you can. Suspension and gears will make 1000x more difference on your car than bolting shit onto that engine. You really can't do anything to it bolt on wise to make much difference. Crack the engine open and degree/advance the intake cams to pick up a bunch of free torque and some extra ponies and make sure your IMRC system is working fine unless its deleted.
1 - Put everything back to OEM including any ignition stuff
2 - Get change your spark plugs
3 - Install a wideband, bug it into your SCT device (if you don't have one get a X3 or X4)
4 - Get ahold of a legit remote tuner to look at datalogs and then tune your car with the stock parts. Sell the parts you bought on the classifieds here or CL or wherever. That cold air and TB are going to make 0 power difference over the stock airbox and TB on a 98 Cobra.
If you are going to mod this Cobra... 4.10 gears, midpipe and catback and then work the suspension as much as you can. Suspension and gears will make 1000x more difference on your car than bolting shit onto that engine. You really can't do anything to it bolt on wise to make much difference. Crack the engine open and degree/advance the intake cams to pick up a bunch of free torque and some extra ponies and make sure your IMRC system is working fine unless its deleted.
NASVT Recipe fixed!!!
NA ~300 RWHP with 96-98 DOHC B-Head 4.6L:
K&N filter
OEM Cams
March damper
March hydraboost and WP pulleys
Long tubes
Hi Flow Cats/Cat Delete mid-pipe
B-Head SRI
90mm LMAF
Tune (canned..more $ for real tuner tune)
350 RWHP:
106100/106060 comp cams properly degreed.
Tune.
NA ~300 RWHP with 96-98 DOHC B-Head 4.6L:
K&N filter
OEM Cams
March damper
March hydraboost and WP pulleys
Long tubes
Hi Flow Cats/Cat Delete mid-pipe
B-Head SRI
90mm LMAF
Tune (canned..more $ for real tuner tune)
350 RWHP:
106100/106060 comp cams properly degreed.
Tune.
Thank you very much
If everything is running right I'd just put the cai on and leave it at that. As far as the throttle body goes if you can't return it you can always sell it on here or throw it on eBay.
Well, at least you've got it running decent now. I agree with @Tunedprt91 about selling the TB. I wouldn't keep any parts you don't absolutely intend to use in the future. Out of sight....out of mind! You'll take a small hit financially on re-selling the stuff you can't return, but in short time this will be all behind you and you can hopefully enjoy your car.
Are you still considering 4.10s? Are you going to do any suspension mods like @scottydsntknow suggested?
Are you still considering 4.10s? Are you going to do any suspension mods like @scottydsntknow suggested?
The suspension is done and done right... it used to be a road racing car. It has a roll cage installed and everything.. it has 3.73 gears in the rear now and I'll probably leave it as is since I plan on doing a kenne bell supercharger in the near future.
Taking the car to a top notch professional next week... time to get it right
You can get 350rwhp off of these cams??
Sent from my SM-G892A using the svtperformance.com mobile app
So the rear 4 link has been replaced with a Torque arm/Panhard bar setup or an IRS? If not then the car wasn't setup for any sort of serious road racing.
Maybe not with B heads but close. 96-98 and 99 intake cams are actually very good and degreeing them will pick up about 20ft lbs of "free" torque plus a little more power. Remember, 350 is with a spot on degree, longtubes, all the other stuff NASVT mentions and a really good tune and you'd probably spend as much on all that as you would for a supercharger which will put you to 400+ easily.
Then you have the guys with said 400+hp 2V and 4V cars on bone ass stock suspension running garbage 1/4 mile times and looking ridiculous with that huge wheel gap.
Google "gibtec aluminator" for what is basically the "4V build bible" thread and read through that. You can probably get near 300 and pick up a LOT of bottom end with a degree/advance of your cams.
All that and more bud
That B head mod list is nasvt approved.
The aftermarket cams mentioned will get you 350 rwhp with b heads...not the oem cams..
As I understand it, the LMAF and B SRI plays a big part in feeding the B (swirl port) heads.
The LMAF is plastic, runs cool and is smooth..
I also think that NASVT has his own spec'd cams as well....that he sells..
ASIDE:
The C (tumble port) heads don't gain from the LMAF...and the C SRI is up in the air for me....depending on the RPM range the car is run at.
From what i have read, The c head cams being off by a few degrees can rob a car of 20 hp. they profit from both sides being degreed to TDC equally.
Some cars got lucky at the factory..some C head engines make 330 rwhp with the first phase mods. It is probably the same story with the SN95 B head cams...and they might make 300+ rwhp with those mods first phase mods and the oem cams
This is the C-head recipe..
NASVT fixed!!!
General consensus for NA ~320 RWHP with 99-01 DOHC C-Head 4.6L:
K&N filter
OEM Cams
March damper
March hydroboost and WP pulleys
Long tubes
Hi Flow Cats/Cat Delete mid-pipe
Tune (canned..more $ for real tuner tune)
360-370 RWHP:
106060 comp cams properly degreed.
short runner (?only ported for oem rpm?)
Tune
The aftermarket cams mentioned will get you 350 rwhp with b heads...not the oem cams..
As I understand it, the LMAF and B SRI plays a big part in feeding the B (swirl port) heads.
The LMAF is plastic, runs cool and is smooth..
I also think that NASVT has his own spec'd cams as well....that he sells..
ASIDE:
The C (tumble port) heads don't gain from the LMAF...and the C SRI is up in the air for me....depending on the RPM range the car is run at.
From what i have read, The c head cams being off by a few degrees can rob a car of 20 hp. they profit from both sides being degreed to TDC equally.
Some cars got lucky at the factory..some C head engines make 330 rwhp with the first phase mods. It is probably the same story with the SN95 B head cams...and they might make 300+ rwhp with those mods first phase mods and the oem cams
This is the C-head recipe..
NASVT fixed!!!
General consensus for NA ~320 RWHP with 99-01 DOHC C-Head 4.6L:
K&N filter
OEM Cams
March damper
March hydroboost and WP pulleys
Long tubes
Hi Flow Cats/Cat Delete mid-pipe
Tune (canned..more $ for real tuner tune)
360-370 RWHP:
106060 comp cams properly degreed.
short runner (?only ported for oem rpm?)
Tune
Last edited:
Cool, what does it have if you don't mind some details and pics?
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