Need help finding cause for lean condition at Idle Whipple 3.0 Gen 5

[919.s550]

If your kit Is a 5 bolt pulley kit (new casting design), do you recall any issues with the blower to head bolts? The 80 mm bolts (inside with o-rings) and the 55 mm (outside) bolts were not the correct size for my kit. The bolts would bottom out and weren't threaded the whole way.. I had to drop down to 75 mm and 50 mm bolts to make it work. I could see this causing all sorts of issues if someone didn't notice during install.

Negative on the bolts causing an intake leak lol may just have to take the blower off and check mating surfaces and lower gaskets. Doubt they’re leaking but at this point it’s about the only thing intake wise I haven’t retouched.

Unfortunately, I don’t know what the trims were. I even dug out my old whipple SD card, no logs saved on it. Hope you get yours figured out!

Also a negative on the casting stands, seems the newer 5 bolt designs got rid of those.

Did you put the o rings on the lower intake bolts inside the manifold? The ones that hold the lower manifold to cylinder head.

Sorry missed your comment, I did. At this point I’m going to remove the blower and hopefully it’s something as simple as a torn o-ring down there, maybe a rolled intake gasket.

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[Nos-pete]

I know when I saw it it didn’t make sense to me seeing the car idle as good as it is.
Fuel Pressure is good (~70ish psi)
I’ve eliminated the PCV reroutes into the intake and have plugs for now just till I find what’s causing this. Valve covers are vented into the atmosphere for now.
Verified Part #s for the injectors, however spoke to my tuner, I have a set of ID1050x we’re going to try, will update this post once those are on. Planning on removing the injectors and rails/play around with them seeing if anything changes maybe the o-rings are not sealing correctly.

Isn’t 70ish psi a bit high ?

 

[Nos-pete]

On 2 occasions we’ve had a lean condition at idle on both my 2020 GT500 and 21 Mach1 both times was the 150mm T.B was causing a fuel cut on injectors at idle only I ditched both and went with the faithful 132mm and am great

 

[engineermike]

Isn’t 70ish psi a bit high ?

If you install a bap and don’t tune for it, it will run 70 at idle. That’s the relief valve setting. Most tuners don’t know how to make the pressure control work when you add a bap.

 

[DMELO2247]

Recent Whipple install has been one headache after another between initial package delivery being delayed, to FexEx completely trashing the 1st blower unit and needing to get another blower shipped out, to missing parts and having to delay install to now having a potential ‘intake leak’ I cannot seem to find. Here’s a little about the car
2019 Mustang GT PP1 w/ Gen 5 3.0 Whipple on a 3.875 pulley
NGK 6510 .028” gap
Stock fuel pump with Lethal Performance BAP
DW95 injectors
93 Octane fuel
132mm Throttle body on stock Whipple closed air box
IAT2 brass temp sensor
Full Corsa exhaust with 1.875” headers

So still trying to get past the base tune. Car seems to idle perfectly to say the least, drives good however at idle after car is warmed up Short term fuel trims climb high have gotten up to 30-45%+ (seem to climb higher and higher the longer the car idles, have only seen it get to 45ish%) indicating a lean condition, was advised by the tuner it’s a intake leak. Aside from looking at the trims you would not know the car is running rough aside from the excessive fuel smell coming from the exhaust. According to car’s vacuum gauge (unsure of accuracy of the thing) it idles at 21inHg.
Now to what I’ve done:
I have smoke tested the system only found 1 leak around the IAT treads which has been fixed but made no change in the fuel trims
Have plugged off intake side of the PCV system and venting the valve cover side.
Have plugged Purge valve line
Have plugged off brake booster line
Have removed SC lid and verified O-ring around the perimeter was good and while in there also checked bypass O-ring. All is good.
Smoked tested a few more times both while engine was cold and hot (was thinking maybe something was expanding and allowing air in?) no smoke exiting was found.
Have also tried the gas Trick around potential leak areas with no change to fuel trims either. I’ve tried looking at other posts, haven’t found one with my issues. I can provide the 2 logs I’ve gotten so far, they’re .csv files but I’m unsure how to post them on here. any help is greatly appreciated

Did you ever figure this out?

 

[919.s550]

Did you ever figure this out?

I did, the bolts that mate the blower unit to the intake ports were ever so slightly too long, unsure as to why since I measured the bolts and they were the correct length as described by the installation manual provided by Whipple. It would only cause the issue to arise as the engine and blower heated up and expanded (Smoked tested system but it clamped down just enough to not let the smoke escape) The inner bolts provided were 80mm, I specially ordered 75mm length bolts and the outside were bottomed out too. I believe i dropped the length by 5mm as well.

 

[mejohn50]

I did, the bolts that mate the blower unit to the intake ports were ever so slightly too long, unsure as to why since I measured the bolts and they were the correct length as described by the installation manual provided by Whipple. It would only cause the issue to arise as the engine and blower heated up and expanded (Smoked tested system but it clamped down just enough to not let the smoke escape) The inner bolts provided were 80mm, I specially ordered 75mm length bolts and the outside were bottomed out too. I believe i dropped the length by 5mm as well.

Interesting. When I first put my kit together I wondered if those bolts were too long. I measured as best I could and figured they were fine. I’ve had some MAF issues that have been (mostly) cleared up with some calibrating. I thought it might have just been a fluke. Looks like I might need to do some disassembling and put some shorter bolts in.

 

[919.s550]

Interesting. When I first put my kit together I wondered if those bolts were too long. I measured as best I could and figured they were fine. I’ve had some MAF issues that have been (mostly) cleared up with some calibrating. I thought it might have just been a fluke. Looks like I might need to do some disassembling and put some shorter bolts in.

Yeah, the inside bolts are recessed so it’s almost impossible to tell they’re bottoming out, I’m assuming the treads were starting to go into the bolt shoulder where the treads end and since the torque that’s needed isn’t crazy high it felt like they tightened. However looking at the outside bolts I was able to see they had a very minimal gap between the bolt head and the blower.

 

[DMELO2247]

I did, the bolts that mate the blower unit to the intake ports were ever so slightly too long, unsure as to why since I measured the bolts and they were the correct length as described by the installation manual provided by Whipple. It would only cause the issue to arise as the engine and blower heated up and expanded (Smoked tested system but it clamped down just enough to not let the smoke escape) The inner bolts provided were 80mm, I specially ordered 75mm length bolts and the outside were bottomed out too. I believe i dropped the length by 5mm as well.

Did you end up ordering new bolts from 2hippleE?or did you shave the ones that were too long?

 

[919.s550]

Did you end up ordering new bolts from 2hippleE?or did you shave the ones that were too long?

I ordered new ones online, believe Amazon lol. That way the new bolts only had treads coming out of the bolt holes from the Blower. If I’d shaven them down it’d still hit the end of the tread on the bolts.

 

[DMELO2247]

I ordered new ones online, believe Amazon lol. That way the new bolts only had treads coming out of the bolt holes from the Blower. If I’d shaven them down it’d still hit the end of the tread on the bolts.

Gotcha, thanks for the help.

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