Can’t figure this out - been going on for over a year now see this vid - boost falls 5-6lbs in upper RPMs:
Blower seems fine after I sent it back and Whipple inspected it.
Shop doing my work is top notch and been building/tuning cobras for 20 years.
It’s not belt slip - have had belts on so tight broke pulley’s & 3 alternators
Assuming not the motor - I had the exact same symptoms when I was on stock motor and then again when on the full built motor. I had weak cylinders on stock motor and actually thought boost drop was the motor was letting go...and why I built it to start.
Shop doing the work has been working cobras 20 years, probably built 100 engines. I used best stuff - stock crank - .020 bore - JE pistons/oliver rods 10:1 comp - ported heads / cams, ID 1050x, FORE fuel, crusher inlet..
Shop did a smoke test for leaks - nothing found. Then we monitored bypass valve with a camera under boost - it is working properly
Before we pull the Whipple and put my old KB back on to see what happens....just seeing if you guys have any ideas what else we can check for.
I’m open ears to suggestions please
Thanks for any help
Blower seems fine after I sent it back and Whipple inspected it.
Shop doing my work is top notch and been building/tuning cobras for 20 years.
It’s not belt slip - have had belts on so tight broke pulley’s & 3 alternators
Assuming not the motor - I had the exact same symptoms when I was on stock motor and then again when on the full built motor. I had weak cylinders on stock motor and actually thought boost drop was the motor was letting go...and why I built it to start.
Shop doing the work has been working cobras 20 years, probably built 100 engines. I used best stuff - stock crank - .020 bore - JE pistons/oliver rods 10:1 comp - ported heads / cams, ID 1050x, FORE fuel, crusher inlet..
Shop did a smoke test for leaks - nothing found. Then we monitored bypass valve with a camera under boost - it is working properly
Before we pull the Whipple and put my old KB back on to see what happens....just seeing if you guys have any ideas what else we can check for.
I’m open ears to suggestions please
Thanks for any help