whipple 4.0
- Thread starter kumar
- Start date
Gulf GT
GT Owner
rydog143,
That's great! Thanks for reading my post the way I intended - we're just trying to be helpful and all learn together. I am certainly far from having all of the answers!!
I too just spoke to Dennis at Whipple to see what was up. (My selfish interest is that I have a 4.0L temporarily off of a car that we are re-assembling tonight.) Dennis conveyed that they saw some collapsing of the intake boot when at full tilt on the dyno. They had the Accufab insert installed when they witnessed this. They removed the Accufab insert sleeve, re-installed the OEM sleeve AND the Accufab sleeve and they no longer saw the problem. So, either the first test was just an anomoly or the best set-up to have is BOTH the OEM sleeve and the Accufab.
I'm just posting what Whipple told me.
Admittedly, I am struggling to rationalize this a little because when we have installed both sleeves, the Accufab fits inside the OEM sleeve.... they were not necessarily in-line. (That's what my old-man memory is.)
But hey, I trust the guys at Whipple and the remedy they said they made. YMMV.
BlackICE
GT Owner
First of all the Accufab sleeve is a real tight fit inside of the stock stiffener at best. Really IMHO they don't fit together at all. Second, something else is not right. If the Accufab sleeve is collapsing the vacuum inside must be very significant. I see it as a band-aid to make it stiffer rather than addressing the real problem. I would measure the vacuum in the air box at two points, post air filters, and post MAF to see how much of a pressure drop is occurring and where. You will never get the full benefits of any blower if the input pressure to it is not all that it could be!
Just spoke to my techs - they have tried the stock/Accufab combo before and said it doens't work - they were also quite dismissive of the collapsing tube theory and more of the view that there is some sort of secondary issue being created by the 4.0L and its effect on the bypass set up.
Has anyone else had the fueling issues FUBAR experienced and needed to fit a Boost-a-pump yet?
Has anyone else had the fueling issues FUBAR experienced and needed to fit a Boost-a-pump yet?
Fubar
Totally ****** Up
Have you tried disconnecting the bypass actuator? If that didn't work then it stands to reason that it is something else.
rydog143
GT Owner
didnt work
changed to a new stiffer air intake tube didn't work still missing boost , Time to have car picked up back to the shop its heading, let u know what they find
changed to a new stiffer air intake tube didn't work still missing boost , Time to have car picked up back to the shop its heading, let u know what they find
Fubar
Totally ****** Up
I suspect they are waiting until they can confirm a cause and solution. It would only add to the frustration it they handed out "possible" solutions. As I understand it, they are looking at the intake plenum and the bypass actuator.
I believe, I fix my problem by manipulating the bypass actuator but I need more road/track time before I would feel comfortable saying that the problem is solved for sure.
If you do not like the BAP solution, you may want to look at a third fuel pump outside of the tank.
I believe, I fix my problem by manipulating the bypass actuator but I need more road/track time before I would feel comfortable saying that the problem is solved for sure.
If you do not like the BAP solution, you may want to look at a third fuel pump outside of the tank.
Please get with the program here.
Gentlemen,
We would sincerely appreciate it if those of you who have installed these 4.0 Whipple Superchargers would redouble your efforts, work around the clock with all possible dispatch, bring in the best available minds, and spend whatever money is necessary to resolve all of these issues quickly! As soon as you're finished, log an adequate number of miles on the road along with dyno runs while monitoring all engine parameters. Then would you please do a detailed and extensive write-up and post it in a new 4.0 install thread that your fellow Forum members and our technicians can access.
Those of us who are not early adopters would like to have a seamless, fully sorted out, and effortless 4.0 L Whipple install and your continuing failures to solve all of these problems in a timely fashon is impeding our progress! Please get your butts in gear and get with the program!!!! :biggrin
Chip
Gentlemen,
We would sincerely appreciate it if those of you who have installed these 4.0 Whipple Superchargers would redouble your efforts, work around the clock with all possible dispatch, bring in the best available minds, and spend whatever money is necessary to resolve all of these issues quickly! As soon as you're finished, log an adequate number of miles on the road along with dyno runs while monitoring all engine parameters. Then would you please do a detailed and extensive write-up and post it in a new 4.0 install thread that your fellow Forum members and our technicians can access.
Those of us who are not early adopters would like to have a seamless, fully sorted out, and effortless 4.0 L Whipple install and your continuing failures to solve all of these problems in a timely fashon is impeding our progress! Please get your butts in gear and get with the program!!!! :biggrin
Chip
Fubar
Totally ****** Up
Okay I want to throw some math at you guys. I know a lot of you are extremely experienced engineers so this might be very enlightening for me.
Clamshell intake opening: (110mm x 75mm) x 2 = 16,500mm surface area
Airbox intake: (105mm x 60mm) x 2 = 12,600mm surface area
Airbox exit: 130mm by 80mm (rounded sides)
(80mm x pi) + ((130mm-80mm) x 80mm) = 4,251mm surface area
Throttle bodies: (72mm x pi) x 2 = 452mm surface area
Doesn't seem like there would be any question where the restriction is. Why does it collapse the plenum?
Clamshell intake opening: (110mm x 75mm) x 2 = 16,500mm surface area
Airbox intake: (105mm x 60mm) x 2 = 12,600mm surface area
Airbox exit: 130mm by 80mm (rounded sides)
(80mm x pi) + ((130mm-80mm) x 80mm) = 4,251mm surface area
Throttle bodies: (72mm x pi) x 2 = 452mm surface area
Doesn't seem like there would be any question where the restriction is. Why does it collapse the plenum?
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Gulf GT
GT Owner
Fubar
Totally ****** Up
FUBAR,
Can't fault the math - though I suppose you get into all sorts of really high tech issues such as air speed, vortices and laminar flow!!
The throttle bodies certainly arent compressible - so if they are the "bottle-neck" then wouldnt it follow that next part of the "chain" would be the part that was compressed/collapsed?
Maybe we need larger throttle bodies???
Gulf GT
GT Owner
Intake filter restriction.
Mark,
You left one big factor out of your measurements. The airbox intake is not really 12,600 mm surface area because it contains air filters that both greatly restrict that intakes effective surface area, and creates both friction and reduces velocity as the supercharger pulls air through it. If you suck on an open plastic soda straw it will be very difficult to collapse it. Cover the open end with a paper towel and the additional resistance encountered when drawing air through that paper filter will enable you to create enough vacuum to collapse the straw. Observe the difference on the dyno in the amount your intake collapses with your air cleaners removed.
Chip
Mark,
You left one big factor out of your measurements. The airbox intake is not really 12,600 mm surface area because it contains air filters that both greatly restrict that intakes effective surface area, and creates both friction and reduces velocity as the supercharger pulls air through it. If you suck on an open plastic soda straw it will be very difficult to collapse it. Cover the open end with a paper towel and the additional resistance encountered when drawing air through that paper filter will enable you to create enough vacuum to collapse the straw. Observe the difference on the dyno in the amount your intake collapses with your air cleaners removed.
Chip
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fjpikul
GT Owner
Fubar
Totally ****** Up
rydog143
GT Owner
The ? is where did the boost go? what went wrong , what is the malfunction? When car was delivered with 4.0 whipple, mafia, heffner pipes , acufab throttle body, it ran like a bat out of hell, easly pinning the gauge to the boost it was set at 19lbs, With crazy top end almost like the wheels were coming of the ground. Now on a good cool day at 160 engine temp on a 1/4 mile hi-way run hard threw 2nd and to the top of third gear canot get the gauge to to go past 12lbs of boost . Even with out the gauge tho u can feel the very top of the range is missing a little , I am by far the least qualified tech person here but always loved fast cars , boats , snowmobiles, ect. and can say i no what fast feels like thats why im saying do not believe its the gauge. Lets put it this way makes more sense to me and hopefully u guys to, lets race the 2 exact same cars, the car when first delivered and car now. I bet the newly delivered car by the time u where at the top of second gear would already start to pull away a little and by the time u made it to 4th it would be good by . I am going try to get it back on the dyno (magic number is 769 on the wheels) that will let me know if im crazy! ...... maybe thanks guys and yes mark got your number didnt want to bother u over the weekend thanks for the message