2.3 Whipple efficiency question

[04GTMustang]

Hey fellas,

I was studying some of my dynosheets and noticed my 2.3 Gen II Whipple running a 2.875" upper with a 100 mm idler and a belt in good shape is making around 19.5 psi and sometimes a bit more (as high as 20.5+) depending on weather. It always seems to drop one full pound of boost regardless of what the max # is that day by the end of the pull. I've never noticed any slipping, but was thinking that this level is basically starting to reach the max efficiency of the 2.3 Whipple.

I have a JLT RAI, I believe an accufab model SBTB, stock whipple non-crusher inlet, long tubes to 3" x-pipe w/ high flow cats. Stock intercooler, stock motor, stock lower pulley.

Has anyone else seen this trend on this blower? I'm wondering if it's slipping a little at the top, and have been seeing those Griptec pulleys popping up which I'm tempted to try. Here's two different pulls in different weather conditions. See the boost line in that yellow color how it starts drop at 4500 and settles off at 5700ish.

EDIT: I measured the graph that didn't show the final boost at the end of the pull, it was 19.7#, so each pull loses about 1-1.2 PSI at the top.

 

[01yellercobra]

How old is the tensioner?

 

[04GTMustang]

How old is the tensioner?

Stock/original...

 

[01yellercobra]

If the belt is in good shape that would be the second suspect on my list. You might just need a new one. Or a new one and a brace. I went with a Roush tensioner as per jrgriffins write up and it's been working really good.

 

[04GTMustang]

If the belt is in good shape that would be the second suspect on my list. You might just need a new one. Or a new one and a brace. I went with a Roush tensioner as per jrgriffins write up and it's been working really good.

Alright, that's a good idea. I'll try a new belt first. That roush tensioner is around $130, versus a new ford one at $70 plus metcos brace for another $80, so not far off. Where is the writeup? EDIT: Found the thread, looks like you just need two washer on the back to shim it, and swap the pulley over?

 

[01yellercobra]

Alright, that's a good idea. I'll try a new belt first. That roush tensioner is around $130, versus a new ford one at $70 plus metcos brace for another $80, so not far off. Where is the writeup? EDIT: Found the thread, looks like you just need two washer on the back to shim it, and swap the pulley over?

That's all I did. And its been working fine for a few months now. But I'm not running an overly aggressive pulley set up.

 

[04GTMustang]

That's all I did. And its been working fine for a few months now. But I'm not running an overly aggressive pulley set up.

Thanks for the pointers. I'm looking into a griptec anyways and maybe an RPM to accompany it, but this tensioner I'm sure has seen better days. Hopefully I don't go through all the hassle of swapping this stuff around to realize the the blower is just done and won't make more with my mods... But that's the risk we take, right?

I can't see how a 2.3 would be tapping out at 17-18 at the end of the pull, but then again with the long tubes with less resistance, maybe it's not able to maintain that peak boost number to redline. I'll post results once I mess around with things..

Now if only it was easy to datalog boost!

 

[BlckBox04]

wait, you made the exact same hp with almost 2# boost difference?

 

[04GTMustang]

wait, you made the exact same hp with almost 2# boost difference?

Yes. I believe that has to do with the applied STD correction factor. The 20.9 psi pull was 20 degrees F and high barometric pressure of 30.25"+. So the car saw huge boost and made 730 RWHP OBSERVED, but the STD correction factor (which is designed to make the conditions the pull was made in irrelevant to showcase actual comparable numbers) put it at the same HP number as it did earlier that year on a warmer, humid day.

 

[jdant]

wait, you made the exact same hp with almost 2# boost difference?

Actually 2.5lbs difference. You would think at peak boost there would be a difference. Maybe fuel system/MAF is maxed out?

 

[04GTMustang]

Actually 2.5lbs difference. You would think at peak boost there would be a difference. Maybe fuel system/MAF is maxed out?

BA2600, still plenty of MAF counts left. Twin 255's, fore hat with -8 feed/return, 80lb'ers, FC3 controller, wasn't going lean. Actually, the higher boost pull (in 20 degrees F making 730 whp observed) the fuel rail press did start to drop at the very end of the pull, but never went lean. I think it's due to the STD correction like I said. But who knows?

 

[jdant]

BA2600, still plenty of MAF counts left. Twin 255's, fore hat with -8 feed/return, 80lb'ers, FC3 controller, wasn't going lean. Actually, the higher boost pull (in 20 degrees F making 730 whp observed) the fuel rail press did start to drop at the very end of the pull, but never went lean. I think it's due to the STD correction like I said. But who knows?

Def not fuel system

 

[04GTMustang]

Def not fuel system

I hope you aren't being sarcastic lmao

 

[stangfreak]

so my 2.9 whipple, at 22-23lbs on the returnless setup made 710rwhp 650rwtq. Tuner said you need a new fuel system its maxed out. Its on the edge. we did a return setup, I then added more boost to the car, 25lbs, ms109, and the car made no more power. It made a little less. I don't remember the exact numbers. so more boost, better fuel, bigger fuel system, nothing gained.

so I decided to drop the boost. Not going to leave the car on 25lbs with ms109 if its not going to make more power. I am spinning the blower and its useless. so why keep that much boost. we put the original pulley back on my car, so it brought it back down to 22-23lbs, put it on the dyno and now the car made 690rwhp 635rwtq. so we looked at the weather conditions. The car when it made less power with the new fuel system, was dynoed on a colder day than when it made 710.

so I think, even a 2.9 will get maxed out at 25 26lbs of boost on a stock motor or something is wrong with the fuel system. sometimes weird shit happens.

And speaking of the 2.3 and efficiency, a long time ago on modularfords, someone did make the behemoth inlet for the 2.3 whipple. Trying to see if it will work like the crusher setup for the bigger blowers. To my memory, the 2.3 whipple with the behemoth, actually made less power. so the stock 2.3 inlet was efficient and designed perfectly for that blower and anything bigger would just make it worse. Again, strange.

 

[04GTMustang]

so my 2.9 whipple, at 22-23lbs on the returnless setup made 710rwhp 650rwtq. Tuner said you need a new fuel system its maxed out. Its on the edge. we did a return setup, I then added more boost to the car, 25lbs, ms109, and the car made no more power. It made a little less. I don't remember the exact numbers. so more boost, better fuel, bigger fuel system, nothing gained.

so I decided to drop the boost. Not going to leave the car on 25lbs with ms109 if its not going to make more power. I am spinning the blower and its useless. so why keep that much boost. we put the original pulley back on my car, so it brought it back down to 22-23lbs, put it on the dyno and now the car made 690rwhp 635rwtq. so we looked at the weather conditions. The car when it made less power with the new fuel system, was dynoed on a colder day than when it made 710.

so I think, even a 2.9 will get maxed out at 25 26lbs of boost on a stock motor or something is wrong with the fuel system. sometimes weird shit happens.

And speaking of the 2.3 and efficiency, a long time ago on modularfords, someone did make the behemoth inlet for the 2.3 whipple. Trying to see if it will work like the crusher setup for the bigger blowers. To my memory, the 2.3 whipple with the behemoth, actually made less power. so the stock 2.3 inlet was efficient and designed perfectly for that blower and anything bigger would just make it worse. Again, strange.

Thanks for writing up all that, interesting to read. You probably were overspinning/slipping with the more aggressive setup and didn't make more. Interesting to hear about the 2.3 inlet, I guess they did it right with that setup.

My tuner (very well respected, Pete Johnson from NH) always comments on how much this little 2.3 can do. He sometimes forgets and thinks it's a 2.9! Not sure if it's just a freak on my car, or what the deal is, but it's consistently 20-30 whp more than an equivalently modded 2.3 TVS car that he sees, and more torque too. Granted, as you crank up the power and have E85 or better fuel, the 2.9 would walk away with it. I've asked him about this before and he seems to think it just might be a limitation of the blower (the drop in boost, that is). Hard to say.

Speaking from experience and what I've observed over the years (and however obvious this is about to sound), fuel mods don't give you more power, they simply allow you to make the power that your engine is set up for. If my fuel system was the restriction here, I would have made the same amount of power on that colder day with more boost at a LOWER RPM. The far more efficacious conditions allowed me to make more observed power at the same RPM as the warmer day, but STD correction made them show the same power. If it was a fuel restriction, I would have gone lean before the end of the pull, and made the same 696 but at a lower RPM because of the higher boost, and the Fkin density altitude that day was -3000. Holy shit!

So no, there wasn't a fuel restriction here. All of my dyno pulls, before and after LT's at over 18PSI has shown this 1psi dip after 4500 that seems to level off by the end of the pull. I was thinking an intake/blower restriction because that boost line doesn't continue to drop off like typical belt slippage. But who knows, maybe it is slipping just a tad. Just bought a griptec and a roush tensioner to see if that does the trick. I'd do a RPM belt too, but considering it's a very mild case of boost loss, I'd think these two changes would definitely fix the problem.

I'm open to any other opinions, however.

 

[c6zhombre]

Nice! That's a ton of hp/tq for pump + torco for a 2.3 gen2! How much timing is in it?

Mines at 714/680 with that same blower....but it's on E85 and high timing, 04sleeper tuned. Factory motor, factory manifolds, magn catted X, factory air inlet/amsoil air filter, factory maf with a mafia, billetflow TB, 2.6 RR upper, factory lower, factory tensioner, whipple adj aux idler, metco support plate, RPM belt (which has worked very well for me....and I've tried all the belts). I see steady 22psi in average weather conditions.

 

[BlckBox04]

Was there a correction factor done on the same day where you said the temperature was much warmer?

 

[04GTMustang]

Nice! That's a ton of hp/tq for pump + torco for a 2.3 gen2! How much timing is in it?

Mines at 714/680 with that same blower....but it's on E85 and high timing, 04sleeper tuned. Factory motor, factory manifolds, magn catted X, factory air inlet/amsoil air filter, factory maf with a mafia, billetflow TB, 2.6 RR upper, factory lower, factory tensioner, whipple adj aux idler, metco support plate, RPM belt (which has worked very well for me....and I've tried all the belts). I see steady 22psi in average weather conditions.

Nice! Thanks for posting your setup/mods/power. If you're getting 22psi consistently across the band with factory air inlet, that makes me think it's more of a slipping issue... I'd venture to say my JLT RAI and BA2600 can flow more CFM than a factory tube and MAF? I also have the stock lower/tensioner if you've read the whole thread, and a snub idler from BF, 100mm. I sold my 2.7 RR pulley today actually (that I never ran because it made too much boost for 93), but will try a griptec in 2.85" and a better tensioner. The RPM belts seem great too, albeit costly, but I've read mixed info on their use from whipple themselves.

Was there a correction factor done on the same day where you said the temperature was much warmer?

Yes, STD correction factor was applied for both pulls, modifying the end numbers against a conversion factor for STD conditions. Which makes sense considering the car had the exact same tune and mods for both pulls, for the exception of going from a BA2400 to a BA2600 MAF for more headroom. So, getting the same numbers under vastly different conditions makes perfect sense with the applied correction factor.

 

[stangfreak]

Thanks for writing up all that, interesting to read. You probably were overspinning/slipping with the more aggressive setup and didn't make more. Interesting to hear about the 2.3 inlet, I guess they did it right with that setup.

My tuner (very well respected, Pete Johnson from NH) always comments on how much this little 2.3 can do. He sometimes forgets and thinks it's a 2.9! Not sure if it's just a freak on my car, or what the deal is, but it's consistently 20-30 whp more than an equivalently modded 2.3 TVS car that he sees, and more torque too. Granted, as you crank up the power and have E85 or better fuel, the 2.9 would walk away with it. I've asked him about this before and he seems to think it just might be a limitation of the blower (the drop in boost, that is). Hard to say.

Speaking from experience and what I've observed over the years (and however obvious this is about to sound), fuel mods don't give you more power, they simply allow you to make the power that your engine is set up for. If my fuel system was the restriction here, I would have made the same amount of power on that colder day with more boost at a LOWER RPM. The far more efficacious conditions allowed me to make more observed power at the same RPM as the warmer day, but STD correction made them show the same power. If it was a fuel restriction, I would have gone lean before the end of the pull, and made the same 696 but at a lower RPM because of the higher boost, and the Fkin density altitude that day was -3000. Holy shit!

So no, there wasn't a fuel restriction here. All of my dyno pulls, before and after LT's at over 18PSI has shown this 1psi dip after 4500 that seems to level off by the end of the pull. I was thinking an intake/blower restriction because that boost line doesn't continue to drop off like typical belt slippage. But who knows, maybe it is slipping just a tad. Just bought a griptec and a roush tensioner to see if that does the trick. I'd do a RPM belt too, but considering it's a very mild case of boost loss, I'd think these two changes would definitely fix the problem.

I'm open to any other opinions, however.

The stock motor can also do so much. I did overspin the 2.9. My tuner said my stock motor right now is just all pumped up. Its all stock, your shoving 25lbs of boost through it, it can only do so much. I know the fuel system doesn't make more power, but, we didnt know how the stock motor and the 2.9 would react to the big boost. I have owned this car since 2003 so, I have no motivation to tinker with it, its good for now. I may get another mustang. we will see.

 

[BlckBox04]

Yes, STD correction factor was applied for both pulls, modifying the end numbers against a conversion factor for STD conditions. Which makes sense considering the car had the exact same tune and mods for both pulls, for the exception of going from a BA2400 to a BA2600 MAF for more headroom. So, getting the same numbers under vastly different conditions makes perfect sense with the applied correction factor.

I think that might show you hit the limit of the blower. With the same correction and set up but with two more pounds you didn’t gain anything.