Flexplate Damage vs Timing Retarders

[Ruth]

Originally Posted by GaryGoFast

Just destroyed my 2nd flexplate in aprox 50 starts. I had a JW Wheel along with a CRS Platinum starter, One kickback and I'd lose a couple of teeth on Wheel. I hate to install a retarder, I hear so many bad things about them. I did just purchase a set of 16 volt batteries to replace my 2 red top Optimas, hopefully that will help. Any other thoughts.
14.7:1 CR, 36 degrees timing.

Assuming that the batteries are good the timing is indeed reading correct and the compression is accurate and the ignition box is good. You might want to voltage drop test the starter circuit both positive and ground circuits.

Using a Digital Volt Ohm meter, hook one lead to the battery positive terminal (not batt cable) and the other lead to the starter positive while cranking the engine you shouldn’t see over .2 volt (.5 volts across a solenoid)drop while cranking ….do the same with the ground side …hook one lead to the negative terminal (not the batt cable) at the battery and the other lead to the starter case again, cranking the engine you shouldn’t see over .2 volts… if you do? you have a problem. You may want to use a meter that uses min –max and freezes that data (most DVOM’s do have this option) so that you can do it by yourself.

Using the voltage drop testing method tests the electrical system dynamicly under actual load conditions.

You may also want to do the same to your ignition box leads….. just in case? … never say never! ….you might be surprised at what you see in voltage drop while cranking and your electrical system is under it’s most sever electrical load condition.

I run a BBC 15.1 and have had issues like you have but only twice in 7 years.
We also run 16volt batteries and once you go there IMO you will never go back.

That being said if you go to 16 volt and all appears to be happy you may only be masking a underlying voltage drop issue that never got addressed to start with...and will only rear it’ ugly head until the final round and of coarse at a national event ( “Ruths law”)

That being said about 16volt batteries ….I know lots of racers with BIG high compression engines that use 12volt batterys with no problems and have done so for many years.

Check that state of charge on the batteries and condition. Load test if at all possible.

Take the surface charge off before you do your load test.

To do so… after being charged properly I usually load 50 amps for @ 15 sec to remove the surface charge…a 12v battery should be 12.6vdc fully charged . Load each battery (if more than one ) separatly and not hooked together to ½ the cold cranking amp spec on the battery and make sure it maintains above 9.5 volts under the load.

Also I like to watch how long the battery takes to come back to a open circuit voltage of 12.6 after the load testing ..15-30-45 sec seems to be fine.

Hydrometer readings ( IF WET CELL and can be tested ) sould be real close to 1.265 fully charged and like relative compression watch for an odd ball cell.

Also ....remember to soften the start when in a jamb... is to wet down the cylinders ( pump the gas 3-4 times) basicly floods the engine and then hold to the floor to start .......it willl slowly light up softening the the harsh kick back condition to get you thru in a pinch.

FYI ......OPTIMA battery quality has gone down hill BIG TIME in the last few years












Hope this helps
Happy hunting

[GaryGoFast]

Thanks for the good information, I will run the full array of testing required at this time. I have the car apart now & I WILL sort it out.

[Anthony Barrett]

Gary,
I went through the same problem. I ate about 3 flex plates and 4 staters. I changed everthing in the ignition and the problem still was there.The last time I damaged a starter I borrowed one from a friend that was for staggered bolts. This solved my problem. I believe my block was drilled wrong. I now use a CSR starter with a 7AL2 and a MSD starter retard. This stater and flywheel have been in there for over 2 seasons. My combo is a 540 with 14.5 CR.

Tony Barrett
SC166H

[245sst]

Hey Gary, when you were getting ready for that drama filled round at VMP, it sounded like a battery voltage issue, made me cringe to hear that noise. Getting rid of those red tops is smart. Double check your rotor phasing. I thought those big motors didn't need that much timing? but what do I know, I run a Pontiac motor......

Something else comes to mind, a buddy of mine mis read the instuctions for his 7al box and there is a wire that is supposed to be grounded to help when cranking, I think his was switched to the ignition instead and he was chewing up flexplates too, just something to look at.


Dave Polichena

[GaryGoFast]

Originally Posted by Lou SG2340

I run a 565 15 t0 1 compression 2 12 volt Delco Batteries. Power Master starter Tci Flex plate. Never any problems in 8 yrs. Suggest u check your tooth pattern & clearance

Congratulations Lou, I heard from Chris you joined the club popping a flexplate at Bristol this weekend, but seriously I would take 8 seasons in a heartbeat.

[sc1153]

Ruth

GREAT DIAGNOSTIC IDEAS

I don't even have a problem in my car and I want to test it. That is something everyone should check just to be safe!

(and the illustrations are awesome, if people dont understand what you meant in that detailed explanation)

[ray carlson]

Gary
I went through 3 flexplates last year.
Had a Digital 6 Plus ,changed to a 7 Plus
Still had the same problem.
Talked to Mike ferderer and he said to take all retard
out. Also when cold pump gas twice then spin
over with a light touch on gas pedal.
Works like a hot damn. I also changed to a bone stock
HP 950 from a modified carb and the combination works great.
Once warn needs just a small shot of gas to start.
Good Luck because I have been there.
Regards
Ray Carlson S/ST # 67