Race car mystery-Help us solve PLEASE
I just fought a simular problem.
My Barracuda went from 6.40 @ 106 MPH to a 6.90 @ 99 MPH.
Thought it was the convertor, sent it in, tighten it up.
Same numbers. sent the convertor back, loosened it up.
Same numbers.
The problem was when the heads were ported, the porter had broken thru the casting on a intake runner at the push rod pinch. It had been brazed up & blended.
ran a leak down, worst cylinder was 2.5 percent.
removed the rockers & installed a plate to vacuum check the intake & heads.
I was suspecting a failed intake gasket.
I could blow into the hose that was hooked up & see it leaking out when I sprayed wd40 on it.
I have since put epoxy on it & going to run it this weekend to see if that fixed the problem.
That lost numbers seem like alot for valve springs.
Check the basics, leakdown to eleminate the short block.
I also had a friend with a 340 that no matter what you did, it would only run 11.20's every time.
I installed my carb (750 holley) same as his & changed the dist., same as his.
The car responded with a 11.56 pass.
These kind of problems will eat you up.
Back to the drawing board for me.
Unloaded the Barracuda this weekend, ran 7.27!
It looked like it left in 2nd gear. It was a turd.
Sounds like a Pro Stocker idling.
My Son said he knew it was going to be a pig in the burnout.
I do have an alternator on this car as well.
It maintains 14 volts at all times.
That is something to check as well.
The one constant is the engine surges thru all gears, it never misses or pop's.
It seems like it is trying to run, but something is holding it back.
I can even hear it on the GoPro, fuel pressure is steady @ 7PSI.
My buddies are pointing their finger at the valve springs, since I found one with an inner spring broken.
I'm also going to check the carb & fuel filter, I'm running Alcohol.
At least we had taken "Ole" Reliable with us & the Son won the first race & got down to 8 in the second race.
Since I have been throwing my money into the Barracuda, we have let the Demon go.
It has 4 bald race tires on it, My Son did a hell of a job driving.
He went 7 rounds, his dial in never changed (7.22). his 60 ft. was anywhere from 1.51 to 1.65 all day.
He used the NOS in 2nd & 3rd gear to make up the difference on every pass.
The final was fantastic, he left the line & the car headed for the tree, I just shook my head.
He had the light & ran dead on!
Used a full bottle of NOS that first race.
His average reaction was .019.
He got beat in the second race, he had a .005 RT to his opponet's .015, he went 1 above & the other guy ran dead on. He said he didn't get on the button quick enough.
Not a bad day for driving by the seat of his pants.
Just ordered a full set of Hoosier's for the Demon this morning.
