Gen 2 Whipple upgrade results

[Palm Harbor GT40]

I had a Generation 2 Whipple installed on my 06. At time of installation a 19-pound pulley was used and I purchased the 21-pound pulley as well. I took the car to Heffner's in Sarasota to have the 21 pulley installed and a 93 tune. When I arrived he did a dyno run to get a base before the pulley swap. The car produced 656 RWHP.

When the 21 was first installed we had a problem due to the pressure blowing the spark out. The plugs were gapped to 28000 and this fixed the problem but the car only made 660 WRHP. He did three more runs after adjusting several perimeters and the power never improved.

I have a Tubi exhaust and he speculated it was causing excessive back pressure and that was the reason the power was not increasing. Jason also felt the power on the 19 pulley should have been greater then the 656.

After a series of test and talking to Shadowman and Torrie, Jason came to the following conclusion. The cause of the problem is the air temperature is being heated to the point of over powering the capabilities of the inter-cooler and the ECU is pulling timing out due to the extreme temperatures. He found that when the car was cool it could make 745 RWHP with the 21 and 715 RWHP with the 19 but for one pull only. Starting on the second pull with both pulleys the maximum power is 660. Based on these results we decided to put the 19 pulley back on.

Jason would you please explain the tests you did and results. Also if my memory of any of the results is off please correct as I want to make sure the results are reported correctly.

Based on these finding I do not know if the Whipple setup can produce maximum power through a 1\4 mile run, 1-mile run, or track event? I do not have any experience with the factory pulley tune upgrade or the twin turbo upgrades. Do they maintain their power for repeated pulls and more important real world and track driving?

 

[lthlvpr]

I think there is something else going on in your car. I had a Whipple on my GT and did about 8 runs on the dyno when the ambient air temp was over 90 degrees. Waited 5-10min btw runs and all of the runs were within 10rwhp of each other which is very consistent when you're dealing with 700rwhp as the frame of reference. Could be the exhaust, perhaps your intercooler, or maybe a bad water pulley. The differences between dyno pulls should not be that large.

 

[soroush]

yes I agree this all seems a bit strange, if you do a search almost everyone who has upgraded to a whipple is making between 700 to 760 hp with the median range being in the 730-740, when I put the 19b pulley on my car it made 719rwhp right out of the gate and eventually after a little tunning it made 730rwhp, granted the weather was cool that day, when I put the 21lb pulley it jumped up to 770hp. 656 seems a bit anemic even taking into consideration the temp. difference, dyno difference, or altitude difference, to give you an idea on the 21lb pulley(770rwhp), we put my car on a different dyno a few months later when the temp. was considerably higher and it made 720 rwhp. I hope you can solve your problem,

 

[Black GT]

I had a problem like yours with my first Whipple. Did you check the by pass valve? On mine if would stick open and bleed off boost. Check the boost with a vacum boost gauge. When Whipple sent me a new one problem solved 740 rwhp on 91 pump. Love the Whipple great power! Just to give you prospective with just a pulley and tune my car made 652rwhp so your car is way off.

 

[HeritageBruce]

Just had my car dyno'd this past weekend and it only pulled 664 WHP on 91 octance (19# pulley). I had another tune in the car that was producing more power but it pinged, this new tune is weaker but at least the car wasn't pinging any more.

 

[dbk]

You guys should also remember that every dyno reads different and I have witnessed another Whipple with 19# put down very similar results on Heffner's dyno. His dyno reads a little bit low from what I can tell, but it is also in a hot, muggy climate. For a pump gas car in Florida on a hot and humid day, if you've been running the car and that blower is getting hot on top of the intercooler, I don't think the results are that out of line.

 

[Shadowman]

First of all I was happy to be involved with the process even though the results were not as all would have liked.

DBK is very correct in that the score sheet from one dyno to another and from day to day can vary drastically; in fact the initial testing on this gal was completed on a hot muggy day however the last testing was done on a cool day breezy day.

Now with regards to this gal; initially when I was called I asked Jason what the downstream air temps were to which I was told 120F which should have caused no issues which is why the Tubi was suspect and removed to see if in fact it was choking the system. At the same time the spark plugs were changed and the supercharger was removed just to see that there were no mechanical issues. Once reassembled without the Tubi the results were in the 700 plus RWHP range so initially everyone thought the culprit had been found; either spark plugs or the Tubi however the original spark plugs were reinstalled and another dyno pull was made and there was little change; still a dyno pull in excess of 700 RWHP was recorded so then the Tubi was reinstalled and she was run on the dyno again with the results remaining once again in the excess of 700 RWHP range as such the Tubi was then determined to be a non issue. Then a series of dyno pulls were made throughout the day and data collected with each of them producing in excess of 700 RWHP however finally dyno pull was made and this time the downstream air temps passed the 150F mark and the power drop was in excess of 60 RWHP; in fact the score card was similar to that which was seen on day one. Ultimately 3 back to back dyno pulls were completed and the discharge air temperature progressively climbed to a figure in excess of 200F at which point the power loss was phenomenal.

It was obvious at this point to Jason that the downstream temperatures were in fact much higher on day one then he had remembered when compared to the 120F as shared.

At this point both Torrie and I suggested that the 21 PSI pulley be removed and the 19 PSI reinstalled because the problem was not being able to tune her for 93 octane but rather high downstream air temperatures and the 19 PSI will reduce the rate of the climb for the discharge air temperatures and even though she would be down on measured net power by 25 RWHP she would produce it for a much longer time.

Takes care

Shadowman

 

[nota4re]

Like Dave & Bill, I'm not sure I read anything in here that would suggest a unique situation on this particular Whipple'd GT.

Two straightforward suggestions - which have already been named. 1) Verify that the car is developing the desired amount of boost. Manifold pressure can be accessed at the front-most, passenger side top of the engine near the fuel rail. 2) Make sure the intercooler pump is working and that the fluid level is at the maximum. Note: It is somewhat common to shunt the intercooler relay "closed" so that the intercooler pump continues to run with the engine off during a dyno sesion. A large electric fan should continue to blow into the GT's radiators to help the intercooler's heat exchanger.

By explicit design, the GT is very sensitive to IAT's. It aggressively pulls timing to reduce HP/heat. If possible, it would be worthwhile to datalog IAT's along with the dyno runs to verify that the HP is consistent with IAT.

 

[Heffner Performance]

When the car first came in, it had just made a one hour drive from Tampa to our shop so the engine and fluids were definitely well heated upon arrival. We pulled the car in, removed the rear belly pan and strapped it to our dyno. All dyno runs were made with a large fan in front of the car. Keep in mind it was almost 90 degrees this day.

The first pull with the 19 pound pulley gave us 665 rwhp. I did think this was low but I have also seen a 50 rwhp variation between the best stock car and the worst stock car. At this point we removed the car from the dyno and proceeded to install the 21 pound pulley and a new set of exhaust tips.

When this was done we strapped the car back on the dyno to see what our 21 pound pulley would give us. We warmed the car up adequately and made the first pull. Throughout this run the car stumbled a bit and showed very low power. I felt that it seemed to be blowing the spark out so we removed the spark plugs and re gapped them to .028". We reinstalled the plugs and proceeded to make another run. I only ran it about half way through this time so I could ensure that the air / fuel ratio was maintaining safely. Now to the next run. Here we go, ready to make some big numbers! Keep in mind that this is now the third consecutive run within a half hour time span on a ~90 degree day. I get the car into fourth gear and put it to the floor. The numbers were in! it made 656 rwhp!? What? I made another run making sure to monitor the Britospeed boost gauge, which worked perfectly, and it showed a solid 21 psi. This run showed 654 rwhp. The air / fuel ratio was about 12 to 1 on all runs. At this point I figured we should let the car cool for a bit. I removed the intercooler pump relay and installed a jumper wire in its place to allow the water to circulate. After letting it cool for about a half hour we went ahead with another run. This one showed 669 rwhp. At this point it is about 6:30 in the evening and we would still have to install the belly pan and Greg would have to make the one hour drive home. I explained that I am very interested in solving the low power issue but we would need a bit more time to go over everything. We decided to get it back to us early the next week.

When the car came back in I wanted to take a very scientific approach to pinpointing the issue. With this mind set we decided to try to eliminate the easiest things first. I haven't heard reports from anyone making big power with a Tubi exhaust. In fact we have witnessed them lose as much as 30 rwhp on some Lamborghini applications. I have also seen spark plugs that look perfectly fine cause a loss of power. I also wanted to verify that the intercooler wasn't damaged or blocked in any way. So we removed the Tubi, replaced the spark plugs and removed the supercharger to inspect the intercooler.

Now we strap it back to the dyno. The first pull after a good warm up showed 714 rwhp. We then reinstalled the Tubi and made another run. This run showed 710 rwhp. We then reinstalled the old spark plugs and made another run. This one showed 708 rwhp. I considered this to be an acceptable range given that all of the runs were made within a close period of time.

At this point I am scratching my head trying to figure out what could have caused such a significant power difference from one day to the next. The most major difference was that the ambient temperature on this day was close to 50 degrees which when using the SAE correction factor should not make much difference.

Throughout these runs I noticed that the downstream air temperatures were around 130 degrees on the first run and would creep up to 160 degrees on the next. Knowing that the downstream air temperatures can play a significant role in the way an engine runs I decided to make a few runs back to back to see what happened. I made three runs with a five minute cool down between each run. By the third run the downstream air temperatures were nearing 200 degrees and power had fallen down into the 660 rwhp range. Not completely satisfied with these findings I decided to repeat this test a few more times. I cooled the car down for about two hours and made a pull. The first run was right back around 710 rwhp. Three runs later we were right back down into the 660s.

What we ended up doing was reinstalling the 19 pound pulley and fine tuning it which made 715 rwhp with a good cool down. The reality is that once everything gets heated up and the air temperatures climb, it will be right back down into the 660s.

I have installed several of the first generation Whipples and do not feel that they heat the air charge as rapidly.

Feel free to ask any questions you'd like .

 

[Gulf GT]

I guess I want my Gen I Whipple back....

Jack at Muscle Motors a few months back was trying to convince me to let him custom enlarge the size of the intercooler tank. He was going to take the factory tank and cut the bottom off of it and extend it down (around a brace) to double its size. He has also suggested a "chiller". Does anyone think these are a good idea in light of this develpment?

 

[Superfly]

He has also suggested a "chiller". Does anyone think these are a good idea in light of this develpment?

Jason (Spddmnjay) here in Alberta is planning something similar I think. He seems to be away this week, but I'll email him and let him know about this so he can chime in.

 

[tmcphail]

I have all the protoype chiller pieces here in my office. I have yet to install them on my car. I was going to do the field development for killer chiller but haven't implemented yet since I am going toward an alternate albeit simpler approach to work towards decreasing downstream temperatures on our cars.

 

[BlackICE]

Anyone that is thinking about increasing the cooling capacity of the intercooler system (laudable goal) should read and understand the math given in the SAE report on the FGT cooling system. The BTU loads the system must extract were eye opening for me! Although, it is possible to buy a few more seconds of cooler operation with a larger buffer of coolant, to get noticeable sustained improvement would require another LARGE heat exchanger and a suitable LARGE source of cool airflow. Also any airflow changes may likely affect the aerodynamics of the FGT and should be approached with caution.

For those thinking of using the A/C compressor to cool the intercooler coolant, that may be of some benefit a short term bursts of low duty cycle. However, it would have a negative effect for sustained high boost use.

 

[FM99]

WOW! Very impressive.

 

[Silverbullitt]

I have all the protoype chiller pieces here in my office. I have yet to install them on my car. I was going to do the field development for killer chiller but haven't implemented yet since I am going toward an alternate albeit simpler approach to work towards decreasing downstream temperatures on our cars.

The Terminator/Lightning guys install a larger heat exchanger. The larger one for the Terminator dropped the temps aboput 50 degrees. Retrofitting one into a GT could be a royal pain since the front end does not have the space available compared to a Mustang or an F150. Some of the aftermarket coolers were much thicker than the stock coolers so they could get more surface area in the same amount of frontal space.

http://www.lightningforceperformanc...cooler-heat-exchanger-200304-cobra-p-319.html

 

[Heffner Performance]

The heat exchanger in the GT is already significantly larger than the one pictured for the Lightning. What would really be slick is be a clutch that could engage and disengage the supercharger so it only runs when you need boost. Mercedes Benz has implemented this into their newe cars. I expect one of you to have this sorted out by morning.:wink

 

[Palm Harbor GT40]

Jason,

Were you watching Mad Max last night?

 

[Mullet]

The heat exchanger in the GT is already significantly larger than the one pictured for the Lightning. What would really be slick is be a clutch that could engage and disengage the supercharger so it only runs when you need boost. Mercedes Benz has implemented this into their newe cars. I expect one of you to have this sorted out by morning.:wink

and we expect you to have a turnkey upgrade package ready by tmorrow night. :biggrin

Yep, the Mad Max scene comes to mind........

 

[Gulf GT]

Although, it is possible to buy a few more seconds of cooler operation with a larger buffer of coolant...

For those thinking of using the A/C compressor to cool the intercooler coolant, that may be of some benefit a short term bursts of low duty cycle. However, it would have a negative effect for sustained high boost use.

Basically, both ideas seem good for drag strip use, but not road course, and that is why I haven't done it.

 

[BlackICE]

+1