Boost dropping of with pulley change?

[Turbo95snake]

So I am still new to the 03 Cobra modding.

I changed the blower pulley to the Lightning one and changed the belt, but my car likes to dump boost. I can-tuned the EEC via Diablo tuner with the 91 octane pulley tune, and am thinking this is the reason.

Eventually I will get over to the tuner and dyno-tune it, but need to know if I can turn off the boost bypass at WOT via Predator or not.

I do not want to manually bypass it for obvious reasons.

Anyone know what table/parameter to adjust or change? Or should I flash the performance pulley tune on it?

Thanks for the help.

-Lance

 

[snkepit]

belt slipping

 

[key]

I have the stock lightning pulley too. It's a 2.93 I believe. Where are you dropping boost? Mine drops down to ~9-10lbs near readline in second gear..

 

[Turbo95snake]

I have the stock lightning pulley too. It's a 2.93 I believe. Where are you dropping boost? Mine drops down to ~9-10lbs near readline in second gear..

mine bogs like hell at 11 psi.. i'm thinking it's the tune and it not disableing the bypass at wot.

 

[Fast Willy]

belt slip.

 

[Turbo95snake]

belt slip.

prevention?

that belt was overpriced!

stock idlers, and the belt went on around the driver idler when it was installed.

went with a 74” K080740 like it says, but on a lightning pulley.

 

[VoodooSNK]

How much PSI is it dropping? Non ported Eatons will drop a couple PSI on the higher RPM's just because they aren't as efficient as they can be.

 

[Turbo95snake]

How much PSI is it dropping? Non ported Eatons will drop a couple PSI on the higher RPM's just because they aren't as efficient as they can be.

back to 8 from 11-12.. way before top-end.. then it feels like it bogs like fuel is dumped in without boost.

are the factory diablo tunes crap or decent till tuned ones?

 

[Steeda30]

Is there any belt dust/rubber built up on the coolant crossover tube right under/behind the blower pulley? Also, is there any dust on the face of the blower?

If the answer is yes, then you're having belt slip. Do you have an idler tensioner pulley that sits right below and to the right of the blower to provide for more belt wrap around the blower pulley?

If you don't, get one from http://www.billetflow.com along with their bracket. Just give them a call if you're not sure which to go with. You'll need a new belt too, one that's a tad bigger in order to accomodate the idler pulley.

Also, if you can't find the right belt size on Billetflow's site, check this out http://www.stangshiftergaskets.com/BeltSelectionGuide.htm

And yes, the Diablosport canned tunes are poop, get a real dyno tune on there as soon as you can. Tell them to tune it for ~11.5 A/F and 23* max timing for 93 octane. If you're running 91, I'd keep it at 20-21* max timing.

Hope that helps! :beer:

 

[Turbo95snake]

Is there any belt dust/rubber built up on the coolant crossover tube right under/behind the blower pulley? Also, is there any dust on the face of the blower?

If the answer is yes, then you're having belt slip. Do you have an idler tensioner pulley that sits right below and to the right of the blower to provide for more belt wrap around the blower pulley?

If you don't, get one from http://www.billetflow.com along with their bracket. Just give them a call if you're not sure which to go with. You'll need a new belt too, one that's a tad bigger in order to accomodate the idler pulley.

Also, if you can't find the right belt size on Billetflow's site, check this out http://www.stangshiftergaskets.com/BeltSelectionGuide.htm

And yes, the Diablosport canned tunes are poop, get a real dyno tune on there as soon as you can. Tell them to tune it for ~11.5 A/F and 23* max timing for 93 octane. If you're running 91, I'd keep it at 20-21* max timing.

Hope that helps! :beer:

Thanks.. I currently do not have an extra tensioner, but will get one.

I used the 2.93 (K080740) belt but guess I will have to get the ½ inch longer one huh?

Thanks for the help.

-Lance

 

[Turbo95snake]

Okay I bought an add-on idler tensioner today and still used the 74 inch belt, but it's pretty tight.

Any downside to it being so tight other than a bitch to R&R?

No more belt slip though!

 

[ZXMustang]

as long as your tensioner is not pegged all the way tight, then you should be ok. Better tight than loose. You need a tad of slack in the tensioner for when the a/c compressor comes on. Right?

 

[Turbo95snake]

as long as your tensioner is not pegged all the way tight, then you should be ok. Better tight than loose. You need a tad of slack in the tensioner for when the a/c compressor comes on. Right?

well it has about 2mm gap from the tightest stop, and the gap seems to grow with revs.

i just don't wanna screw up the alternator or blower.