Best upper lower to reach 25 ilbs boost on 2.9 whipple

[2004cobra615]

So I have some questions.

Looking to make 700 plus RWHp but gain lOW end torque... If can out of the 2.9 whip. I have heard it shines at around 25 Ilbs or higher. It's a stock motor so I don't want to go crazy or swtich everything on the car.

What's the best combo to reach 25ish ilbs boost with my 2.9 Whipple running e 85?

I have a accufab single blade TB, jlt ram carbon fiber intake and standard inlet 2.9 Whipple second gen. JBA shorthy headers 80ilb deka injectors and lethal budget return. I'm in Illinois so air isn't to thin.

Will a 3 inch upper make to 25 ilbs alone.
If i throw a 3 inch pulley on the Whipple will I have belt slip.... is that why the lower comes in handy here? My 3.5 pulley I have no issues with slip

I would prefer to keep stock lower but is there a huge benefit to changing it besides risking my crank snout.


From what I have read I think a 3 inch upper with stock lower should be 23 to 25 Ilbs correct... Other advice for increasing the low end torque/hp? anyone with this set up can you chime in. Help is much appreciated.



2004 Cobra 2.9 Whipple

 

[MG0h3]

Typically the harder you spin it the quicker the torque comes on as the boost is right there at low rpm.

I’m on a 2.9 RR upper/stock lower and no slip. Snub idler.

I’m at 4k’ and only see 19-20 but at sea level it should be around 23-24.




Sent from my iPhone using svtperformance.com

 

[apex svt]

Try to get in touch with @MalcolmV8 he’s done a lot of testing with the 2.9.

 

[2004cobra615]

Typically the harder you spin it the quicker the torque comes on as the boost is right there at low rpm.

I’m on a 2.9 RR upper/stock lower and no slip. Snub idler.

I’m at 4k’ and only see 19-20 but at sea level it should be around 23-24.




Sent from my iPhone using svtperformance.com

Hmm I'm at 18/19ilbs with the 3.5 upper and stock lower.

2004 Cobra 2.9 Whipple

 

[2004cobra615]

Try to get in touch with @MalcolmV8 he’s done a lot of testing with the 2.9.

Most of the stuff I have read is from malcomv8 he had a built motor plus crusher Intake tho so it's not apples to apples

2004 Cobra 2.9 Whipple

 

[Stage 4.6]

Curious about this question as well I've been thinking about going the 2.9 Whipple route. I have a 4lb. lower though,

I believe theirs an thread on here with several different blower combos that might be helpful?

 

[cj428mach]

25psi will be more than your 80s can supply for, you re also pushing the stock head bolts. On e85 it should be around 800rwhp.

Edit: should be around 800 on 25 psi.

 

[Nadra]

25psi will be more than your 80s can supply for, you re also pushing the stock head bolts. On e85 it should be around 700rwhp

I agree. While possible(?), you will def be at the ragged edge on the 80s. ID1000s or 1300s are a better choice. And yeah, 25 psi is starting to really ask a lot from the OEM head bolts but more specifically the head gaskets. Most guys like you (us) who are shooting for 700ish try to stay around 21-22 psi on e85. At 25 psi from a screw blower, you are at or fast approaching the sealing capabilities of the std. MLS head gasket. You can add a little more boost from a turbo or TT setup and most would say factory head gaskets would survive but again, your weak link is still the factory head bolts. For reference, I have ARP2000 head studs in mine and I still keep it around 21 psi.

 

[2004cobra615]

I agree. While possible(?), you will def be at the ragged edge on the 80s. ID1000s or 1300s are a better choice. And yeah, 25 psi is starting to really ask a lot from the OEM head bolts but more specifically the head gaskets. Most guys like you (us) who are shooting for 700ish try to stay around 21-22 psi on e85. At 25 psi from a screw blower, you are at or fast approaching the sealing capabilities of the std. MLS head gasket. You can add a little more boost from a turbo or TT setup and most would say factory head gaskets would survive but again, your weak link is still the factory head bolts. For reference, I have ARP2000 head studs in mine and I still keep it around 21 psi.

Thanks for the heads up. What pulley will be needed to make it to 22 ilbs.


2004 Cobra 2.9 Whipple

 

[GodStang]

I have been running 80lbs, E85, and close to 800rwhp and my setup since 2012 and still has plenty of room. E85 has hit 900rwhp on a blower setup before. While I agree ID1000s or ID1300s would be better, 80lbers are more than enough to hit his goals.

25psi will be more than your 80s can supply for, you re also pushing the stock head bolts. On e85 it should be around 800rwhp.

Edit: should be around 800 on 25 psi.

I agree. While possible(?), you will def be at the ragged edge on the 80s. ID1000s or 1300s are a better choice. And yeah, 25 psi is starting to really ask a lot from the OEM head bolts but more specifically the head gaskets. Most guys like you (us) who are shooting for 700ish try to stay around 21-22 psi on e85. At 25 psi from a screw blower, you are at or fast approaching the sealing capabilities of the std. MLS head gasket. You can add a little more boost from a turbo or TT setup and most would say factory head gaskets would survive but again, your weak link is still the factory head bolts. For reference, I have ARP2000 head studs in mine and I still keep it around 21 psi.

 

[cj428mach]

I have been running 80lbs, E85, and close to 800rwhp and my setup since 2012 and still has plenty of room. E85 has hit 900rwhp on a blower setup before. While I agree ID1000s or ID1300s would be better, 80lbers are more than enough to hit his goals.

I dont know how you pulled that off. Injector dynamics website has a calculator and the 1000s are being pushed in the low 20 psi/700rwhp range. id1000s are 95lb i believe. More power to you but id never recommend a borderline injector for a whipple or kb. You have to pull the blower to swap them, probably out $$ on dyno/tune time, and then the loss on selling your old injectors and buying new.

 

[GodStang]

There are many many people that have 80lbers and over 800rw on corn. I had 80lb injectors, I pulled them and switched to ID injectors and there were too many problems (across teh board not just me) with them at the time. So I talked to my tuner and he said do 80s. So I took the car apart again and got rid of the IDs and went back to the 80s and had plenty of room. Drives insanely well. Now of course at that time there were no ID1300s and if I end up doing my rebuild I probably will go back to IDs.


You can see the IDs already installed on my car before I had to pull them.

I dont know how you pulled that off. Injector dynamics website has a calculator and the 1000s are being pushed in the low 20 psi/700rwhp range. id1000s are 95lb i believe. More power to you but id never recommend a borderline injector for a whipple or kb. You have to pull the blower to swap them, probably out $$ on dyno/tune time, and then the loss on selling your old injectors and buying new.

 

[2004cobra615]

There are many many people that have 80lbers and over 800rw on corn. I had 80lb injectors, I pulled them and switched to ID injectors and there were too many problems (across teh board not just me) with them at the time. So I talked to my tuner and he said do 80s. So I took the car apart again and got rid of the IDs and went back to the 80s and had plenty of room. Drives insanely well. Now of course at that time there were no ID1300s and if I end up doing my rebuild I probably will go back to IDs.


You can see the IDs already installed on my car before I had to pull them.

View attachment 1517035

04 sleeper said 80ilb injectors would be enough for for 750 on my set up.

2004 Cobra 2.9 Whipple

 

[Nadra]

Guys - I stand corrected. I plugged everything into the fuel system calculator, and with the 2.9 blower and a pulley combination that yields 22.4 psi (3.1 upper/stock lower) @ 1,000 feet above sea level (just used this as a rough avg, psi will obviously change a little depending on your local altitude) the 80's are more than enough even at 95% DC. I'm not used to looking at data on the 2.9 - so my bad.

 

[Nadra]

04 sleeper said 80ilb injectors would be enough for for 750 on my set up.

2004 Cobra 2.9 Whipple

Listen to Kevin...he knows his stuff. He is no doubt the pioneer when it comes to e85 and 03-04 Cobra Mustangs. That is not hyperbole; that is fact.

 

[2004cobra615]

There are many many people that have 80lbers and over 800rw on corn. I had 80lb injectors, I pulled them and switched to ID injectors and there were too many problems (across teh board not just me) with them at the time. So I talked to my tuner and he said do 80s. So I took the car apart again and got rid of the IDs and went back to the 80s and had plenty of room. Drives insanely well. Now of course at that time there were no ID1300s and if I end up doing my rebuild I probably will go back to IDs.


You can see the IDs already installed on my car before I had to pull them.

View attachment 1517035

The Ids 1300 are expensive and are mainly for E85. So I want to be able to go back and forth to 93. I think going from 600rwhp to 720 750 on E85 is enough of a jump for a few years with the 80ilb ers

Honestly the 600 rwhp is getting boring. The 3rd gear pulls in high rpms always put a smile on your face but low rpms honestly it falls flat.



2004 Cobra 2.9 Whipple

 

[GodStang]

Yep that is what I did with my ole 2.8LC. 93 octane for low 700s and E85 for high 700s. I would swap pulley/belt/tune when I switched fuels in under 10 mins. With my new setup I dropped the 93 and run E85 at all times do to 30+ psi.

The Ids 1300 are expensive and are mainly for E85. So I want to be able to go back and forth to 93. I think going from 600rwhp to 720 750 on E85 is enough of a jump for a few years with the 80ilb ers

Honestly the 600 rwhp is getting boring. The 3rd gear pulls in high rpms always put a smile on your face but low rpms honestly it falls flat.



2004 Cobra 2.9 Whipple

 

[Nadra]

Yep that is what I did with my ole 2.8LC. 93 octane for low 700s and E85 for high 700s. I would swap pulley/belt/tune when I switched fuels in under 10 mins. With my new setup I dropped the 93 and run E85 at all times do to 30+ psi.

You are 30 psi on a screw blower?

 

[BLOWN9646]

You are 30 psi on a screw blower?

Pretty sure Godstang runs the 3.2LC, for sure on a built motor

 

[holiks03cobra]

I run a 3.0/2lb setup, I even had a 4lb lower on for a little bit. Its around 24lbs of boost. I have 1 3/4 long tubes and 3" exhaust so I'm sure that drops my boost a tad. I have had my aftermarket lower on for many years and never had a problem. I am not easy on my car either. I will add that my last motor didn't like that much boost. It ended up lifting a head. It was a reman motor with stock head bolts.