LT and Ford Racing 90 MM TB?

[BOOSTD5.4]

Ford Racing 90 MM TB?

Just installed the 90 MM Ford racing TB and had the car tuned.

Made 440 to the tire with full exhaust.

The car runs great, BUT the RPM seems to hang up from higher RPM's....

Also my torque dropped from 420 to 378 with the LT and TB........

Anyone else have this with the Ford TB?

Thanks!

Mike

 

[ryan.garcia2733]

Also my torque dropped from 420 to 378 with the LT and TB........

Thanks!

Mike

This doesn't sound right at all???!!! Longtubes are supposed to raise tq significantly not lose.

 

[JimIII@jdm]

I agree doesnt seem right that you lost that much torque, was there a tune adjustment made at the same time? What system is the exhaust and are you running cats on the car as well. The hanging throttle can be fixed in the tune we make adjustments for these often.

 

[Sean@LethalPerformance]

My car but down 426/370 SAE after getting dyno tuned and added headers before the the engine got dropped in, I don't have the 90mm ford raging tb, but I have the 84.5 accufab who makes the ford racing tb.. I was at least expecting more Tq and hp myself.. But before my engine went and I only had intake, manifold and xpipe, I was betting full Bolton 5.0's that where puttin down 450whp on perhaps more friendly dynos.

Hopfully next week Ill have an apt to retune my car bc iv been having idleing/stalling issues which I thought to be caused by the tb.

 

[BOOSTD5.4]

I agree doesnt seem right that you lost that much torque, was there a tune adjustment made at the same time? What system is the exhaust and are you running cats on the car as well. The hanging throttle can be fixed in the tune we make adjustments for these often.

The car ran like crap with the last tune before the LT and TB..... Pete @ Performance Dyno retuned it.

I have the American Racing 1 7/8 LT Headers with high flow cats into the Bassani axle backs, minus the side pipes...... Car is way quieter than before

Mods: JLT intake, FR 90 MM TB and Boss spacer, SCT tuner with custom tune, Headers into Bassani, a CF Driveshaft with Steeda Loop, Whiteline upper and lower control arms, BMR K member and a arms, and a Steeda TRI Ax shifter with bushings.

The car feels faster at WOT, but the torque loss is noticeable in every day driving...... May be scrapping the 90 MM TB.....

Mike

 

[SCalla1384]

Boss's tq readings are usually pretty low because of the intake. Your torque actually seems normal now then it did before (420lbft)

Also, who tuned it before Pete? Pete's the man, he does great work. He'll be tuning my GT very soon.

 

[BOOSTD5.4]

Boss's tq readings are usually pretty low because of the intake. Your torque actually seems normal now then it did before (420lbft)

Also, who tuned it before Pete? Pete's the man, he does great work. He'll be tuning my GT very soon.

Pete has tuned it the first time. He drove it and felt it made great power. It's a little quirky?

I think the issue is the TB. If feels like the blade stays open. If Accufab produces this for Ford, I am REALLY disappointed!

Pete does great work and Dan is a great installer next door!

Mike

 

[SCalla1384]

What was wrong with the tune the first time ?

And yea, it wouldn't hurt taking it back to the Dyno on the factory throttle body.

 

[dead man walkin]

I was actually coming here to ask about the 84.5 and the 90 TB's this morning... OK boosted... I'll buy your used 90 for $100.00 you know being used and all!! Ha ha... I wonder if the boss intake in combo with the 90 is just too much air at the wrong time and kills torque? Find someone and swap an 84 and run a dyno.. I think until you go forced induction. 84.5 is the biggest you should go

 

[Dizzyscure1]

Hmmm... how many Coyotes and Roadrunners has he turned? If only a hand full then he may not have the experience to tune to your car properly. there are a few people who I would trust to touch the 5.0 as far a tuning goes, maybe look into another tuner.

 

[Dizzyscure1]

Boss's tq readings are usually pretty low because of the intake. Your torque actually seems normal now then it did before (420lbft)

Also, who tuned it before Pete? Pete's the man, he does great work. He'll be tuning my GT very soon.

Whos this Pete?? Shop name??

 

[5PNTSLO]

The car ran like crap with the last tune before the LT and TB..... Pete @ Performance Dyno retuned it.

I have the American Racing 1 7/8 LT Headers with high flow cats into the Bassani axle backs, minus the side pipes...... Car is way quieter than before

Mods: JLT intake, FR 90 MM TB and Boss spacer, SCT tuner with custom tune, Headers into Bassani, a CF Driveshaft with Steeda Loop, Whiteline upper and lower control arms, BMR K member and a arms, and a Steeda TRI Ax shifter with bushings.

The car feels faster at WOT, but the torque loss is noticeable in every day driving...... May be scrapping the 90 MM TB.....

Mike

Boss's tq readings are usually pretty low because of the intake. Your torque actually seems normal now then it did before (420lbft)

Also, who tuned it before Pete? Pete's the man, he does great work. He'll be tuning my GT very soon.

I was actually coming here to ask about the 84.5 and the 90 TB's this morning... OK boosted... I'll buy your used 90 for $100.00 you know being used and all!! Ha ha... I wonder if the boss intake in combo with the 90 is just too much air at the wrong time and kills torque? Find someone and swap an 84 and run a dyno.. I think until you go forced induction. 84.5 is the biggest you should go

Maybe you guys see something I don't, but he never said anything about having a BOSS intake, only a BOSS spacer for the 90mm throttle body

 

[charba951]

Maybe you guys see something I don't, but he never said anything about having a BOSS intake, only a BOSS spacer for the 90mm throttle body

OP has a BOSS 302 :shrug:

 

[BOOSTD5.4]

Performance Dyno is Pete's shop in Loudon, NH.

I will grab an Accufab 84.5 to see if it helps the car! Thank You for the recommendations!

These mods are on my 12 Boss.

( I am posting in the GT forum, as many of the Boss owners keep their cars stock......)

Thanks All! Happy Memorial Day! Thank You all who have Served!!!!

Mike

 

[JimIII@jdm]

The car ran like crap with the last tune before the LT and TB..... Pete @ Performance Dyno retuned it.

I have the American Racing 1 7/8 LT Headers with high flow cats into the Bassani axle backs, minus the side pipes...... Car is way quieter than before

Mods: JLT intake, FR 90 MM TB and Boss spacer, SCT tuner with custom tune, Headers into Bassani, a CF Driveshaft with Steeda Loop, Whiteline upper and lower control arms, BMR K member and a arms, and a Steeda TRI Ax shifter with bushings.

The car feels faster at WOT, but the torque loss is noticeable in every day driving...... May be scrapping the 90 MM TB.....

Mike

Okay, having 1 7/8 is probably the reason for your big torque loss. Those primaries are better suited for higher power applications. We usually dont use 1 7/8 untill over 700 RWHP. The 1 3/4" primaries are better for keeping a healthy torque curve. Im sure if feels really good up in the higher RPM band because at WOT the manifold, TB and Longtubes together will move a ton of air. Removing all that back pressure from adding this large of a diameter exhaust will create your sound loss.

I really like the 84.5mm TB. The 90mm creates a wall at the manifold and will not add any more flow than the 84.5mm will. The Boss manifold has an 84.5mm opening so your better off matching the size of the inlet.

If you have any questions feel free to contact me at 732-780-0770 during our office hours or email me at [email protected]!

Thanks,

JimIII

 

[IT-Purrrs]

Okay, having 1 7/8 is probably the reason for your big torque loss. Those primaries are better suited for higher power applications. We usually dont use 1 7/8 untill over 700 RWHP. The 1 3/4" primaries are better for keeping a healthy torque curve. Im sure if feels really good up in the higher RPM band because at WOT the manifold, TB and Longtubes together will move a ton of air. Removing all that back pressure from adding this large of a diameter exhaust will create your sound loss.

I really like the 84.5mm TB. The 90mm creates a wall at the manifold and will not add any more flow than the 84.5mm will. The Boss manifold has an 84.5mm opening so your better off matching the size of the inlet.

If you have any questions feel free to contact me at 732-780-0770 during our office hours or email me at [email protected]!

Thanks,

JimIII

I call for a sticky on this. Thanks for the info!

 

[BOOSTD5.4]

Okay, having 1 7/8 is probably the reason for your big torque loss. Those primaries are better suited for higher power applications. We usually dont use 1 7/8 untill over 700 RWHP. The 1 3/4" primaries are better for keeping a healthy torque curve. Im sure if feels really good up in the higher RPM band because at WOT the manifold, TB and Longtubes together will move a ton of air. Removing all that back pressure from adding this large of a diameter exhaust will create your sound loss.

I really like the 84.5mm TB. The 90mm creates a wall at the manifold and will not add any more flow than the 84.5mm will. The Boss manifold has an 84.5mm opening so your better off matching the size of the inlet.

If you have any questions feel free to contact me at 732-780-0770 during our office hours or email me at [email protected]!

Jim,

Will the 84.5 help with the hanging rpm's? Will it add any HP over the OEM Boss unit

How much for the Accufab 84.5?

I am surprised how quiet the car is with the LT and the Bassani mufflers...... Seems 20% less loud than with the Bassani and the side pipes opened!

All about weight savings for me..... Bet I shaved 150#'s off the car so far! Wheels, exhaust, driveshaft, K Member and a-arms!

Thanks!

Mike

 

[balboky01]

OP, i have the FRPP 90MM with headers and i dont have any issues with the drive-ability. I have it tuned by BBR

 

[JimIII@jdm]

Okay, having 1 7/8 is probably the reason for your big torque loss. Those primaries are better suited for higher power applications. We usually dont use 1 7/8 untill over 700 RWHP. The 1 3/4" primaries are better for keeping a healthy torque curve. Im sure if feels really good up in the higher RPM band because at WOT the manifold, TB and Longtubes together will move a ton of air. Removing all that back pressure from adding this large of a diameter exhaust will create your sound loss.

I really like the 84.5mm TB. The 90mm creates a wall at the manifold and will not add any more flow than the 84.5mm will. The Boss manifold has an 84.5mm opening so your better off matching the size of the inlet.

If you have any questions feel free to contact me at 732-780-0770 during our office hours or email me at [email protected]!

Jim,

Will the 84.5 help with the hanging rpm's? Will it add any HP over the OEM Boss unit

How much for the Accufab 84.5?

I am surprised how quiet the car is with the LT and the Bassani mufflers...... Seems 20% less loud than with the Bassani and the side pipes opened!

All about weight savings for me..... Bet I shaved 150#'s off the car so far! Wheels, exhaust, driveshaft, K Member and a-arms!

Thanks!

Mike

Mike,

I dont think changing the throttle body itself would fix your hanging RPM condition right away, maybe help a little but sounds like it is tune related. Most of the time if the calibration is set up properly for a larger TB this wont happen, if it does you could be looking at the TPS. We carry the Accufab 84.5mm on our website. I agree with you about the weight savings and I bet your right about it being 150lbs, that exhaust is heavy plus the DS and all that suspension...easily that much weight!

JimIII