Boost bypass actuator issues. Large Cams with BACT-1015 actuator.

[Beffastang]

I have a fully built long block with custom grind cams. 479 lift with 247 degrees of duration at .50 intake and exhaust. I have the whipple light spring actuator installed the BACT-1015. The baypass valve barely opens and the engine pops and surges until I hold the valve open then it smoothes out. Any one have any ideas on what to do now?

 

[olympic]

The only solution I've heard is to use adjustable cam sprockets to dial out some of the valve overlap. This helps boost idle vacuum in the intake manifold. Unfortunatley this involves removing the engine to degree the cams. My car has poor street manners due to low vacuum and if I ever have the engine out I'll be looking into this.

 

[04torchred]

How much vacuum are you pulling at idle? I have 10-11" at idle on mine and I idle great with the low pressure actuator from whipple. Did you test it off the car first to see if it was sticky or faulty?(Just a question)

 

[Beffastang]

Yes I did test the actuator it was way easier to open than the stock one. I haven’t tested my car to see how much vacuum it’s pulling yet.

 

[Beffastang]

I was told that the L & M actuator could be lighter then the whipple one. Does anyone have any experience with both of them?

 

[01yellercobra]

Find out how much vacuum the engine is pulling.

 

[Beffastang]

I just did a vacuum test, the engine is pulling 6-7lb of vacuum. The cams are also set right on the sprocket marks. The cam specs are below, will the L & M actuator function with 6-7lbs of vacuum? The Whipple light spring one will not.

 

[04torchred]

You are going to have to call Michael at L&M for that answer as they don't list a vacuum value.

- Low vacuum bypass for Eaton and Whipple superchargers
- WILL NOT FIT WHIPPLE CRUSHER INLET
- Fits 2V, 3V, GT500, and Cobra
- NOTE: The low vacuum bypass sold by Whipple WILL NOT WORK with our cams. If you do not use our low vacuum bypass you will not be able to properly tune your vehicle.

 

[cj428mach]

https://www.svtperformance.com/thre...on-boost-bypass-valve-on-2-9-whipple.1103918/

Another great Malcolm thread.

 

[can04cobra]

I was told that the L & M actuator could be lighter then the whipple one. Does anyone have any experience with both of them?

After reading your thread here and having a similar issue with larger cams I ordered L & M bypass. It holds open the bypass with 0 vacuum like its half way open when the car isnt even running. at only 1in hg vac it is fully open. To close the bypass I hooked up a vac hose and blew into it and it closed so I would guess fully closed 1psi boost. I haven't been able to drive the car since install. Now with weather up here car is away for the winter. I'm hoping this has resolved the bucking/surging issue I was encountering. Will be a long wait for winter to pass. If anyone else is running one with larger cams please let us know how it is working for you.

 

[can04cobra]

Just thought I'd update my previous post. The L&M engines low pressure boost bypass actuator works great. I also had the car remotely tuned by Decipha member on here and car drives like stock no bucking or surging. Hope this helps if anyone Is looking into getting the bypass actuator.

Sent from my SM-G960W using the svtperformance.com mobile app

 

[Bluewrx2001]

When installing the bypass actuator any way to do without removing fuel rail?