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rklessdriver 10-09-2016 MPC Real Street race
Senior Guru
Woodbridge, VA
1310 Posts
Member since:
2008/1/4 0:00



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Had high hopes coming into this weekend that I would finally get the 5.3X pass. The past 2 races the car has been faster than ever and just minor problems have been keeping me from going rounds.

Minor changes to the car from the last race. I set the fuel pressure for the nitrous up to 7psi (was at 6psi) to account for the better air conditions.

First off it rained us out on Saturday, so we had make up the next day Sunday and the weather was beautiful. High 50's, water grains showing low 40's and DA of about 1,100 ft.

Also my friend blackharleyman came out to watch.

Q1 - I expected the car to rattle the tires (has done it almost ever pass in Q1 this year) and sure enough it did... I was ready, pedaled it and went a 5.70@126MPH with a horrid 1.45 60ft.

I also expected it to not go up on the trans brake clean... sure enough it stuttered and stumbled before clearing out. Despite looking at everything in the carburetor, I could not find the problem.

Q2 - I expected the track to be better and the car to rip off a pass.... well the track was better and the car tried to rip off the back bumper again. I pedaled the car 3X and it just kept slamming down, then bouncing the front up higher and higher until I almost hit the wall and had to get out of it.

It did go 1.23 60ft tripping the timer with the back tires.....

Video on face book.

https://www.facebook.com/clif.williams.7/videos/10205579048074476/

The track photographer got a series of the first wheel stand past the 60ft lights but didn't get other 2 bounces. You can see I let it get pretty high before attempting to pedal...

https://bandbphotos.smugmug.com/KOTT-MPC-REAL-STREET/i-LsBt72q/A

It hit hard enough to drag the new oil pan on last hit and mashed the front of it up.... at least it's not leaking.

Again the car wasn'r clean comming up on the brake either....

E1 - I took some power out of the progressive controller and hoped for the best. Damn engine didn't go up on the brake clean again, but this time it backfired and shut off in a ball of flames.... I shut everything off, got it restarted and went back to the pit.

We started trouble shooting the problem (again). Yep the squirters on the carb are working, yep it's pulling fuel from the booster..... So I get the timing light out.. totally at a loss I wonder if the box is pulling timing once I engage the trans-brake.

I ask blackharleyman to sit in the drivers seat while I check the timing, fire the car off, he puts it in low gear and pushes the trans-brake button.... nothing - timing stays rock solid... we go thru this couple times but then I notice the timing is not at 31*.... it's at 25*. I double check and sure enough the timing is wrong.

So anyway I reset it to 31* in the pit and sure enough the car goes right up on the trans-brake easy as pie....

So now I'm at a point where I wonder if the timing was ever at 31*.... did I accidentally move the dizzy when we reset it back 2 races ago or is something mechanical going crazy.

Here's the other thing.... if it's been at 25* this whole time, I have been running with only 10* going down the track... and the car is absolutely flying. Not to mention the timing mark on the plugs was perfect the previous 2 races.... However it was not even readable on Sunday.... I assumed due to weather it had moved down the bend towards the threads (which I expected) but maybe if the timing moved from 31 to 25 is actually moved off the other end....

I honestly don't know WTF is going on. Maybe I sleep walked down to the garage and reset my timing.... Maybe elves came while I was at work and reset my timing.... Maybe it was never at 31* to begin with... maybe something is going haywire in the dizzy.

I have already checked out my cam belt drive and it's tight, belt is still good... I'm going to pull the distributor cap and rotor off tonight and check it for anything loose. I'm going to check my timing pointer to see if it's loose.... ATI balancer so it can't spin....

Can anyone think of anything else that might be the problem? I mean I am totally flustered with this problem and very well could be overlooking something simple....

One race left and I'm really hoping to get that 5.3X pass before the seasons over and hopefully not hurt anything doing it.

Thanks
Will
Posted on: 2016/10/11 14:42
_________________
1984 Corvette. 434 SBC with a Powerglide.
Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials.

1972 Corvette. LS5 454 BBC with M20 4 speed.
Best Pass - Doing good to just pass a gas station.
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pianoguy Re: 10-09-2016 MPC Real Street race
Elite Guru
Apple Valley, MN
14619 Posts
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Wow, you did get some air! That timing issue is screwy, indeed!
Posted on: 2016/10/12 1:01
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1996 LT4

´┐ŻBefore you criticize someone, you should walk a mile in their shoes. That way when you criticize them, you are a mile away from them and you have their shoes.´┐Ż- Jack Handey
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Matatk Re: 10-09-2016 MPC Real Street race
Webmaster
SW Chicago Burbs
21412 Posts
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Hopefully the timing fix makes it run right.
Posted on: 2016/10/12 3:03
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1989 Corvette...custom 383 stroker, superrammed and cammed, built trans with PeteK 2800 stall. Mustang dyno results: 336 rwhp / 419 rwtq.
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TommyT-Bone Re: 10-09-2016 MPC Real Street race
Chair-man of the bored
Homestead USA
30528 Posts
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2007/12/10 0:00



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Holy crap, that was a lot of pics. Enjoyed many.

https://bandbphotos.smugmug.com/KOTT-MPC-REAL-STREET/i-LsBt72q/A

Posted on: 2016/10/12 3:24
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BillH Re: 10-09-2016 MPC Real Street race
The Stig Moderator
Reno
22702 Posts
Member since:
2007/12/25 0:00



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Gawd Will, that thing sure carries the front end a long way.

I can't see anything more you can do with the disty except make another run and check it.
It's such a bitch with what we do when the only time you can test things is at the track (time and money).
We're in the same boat.

And we had to cancel this weekend's 4 day event because the car owner got a new job.

Noticed the "Antrim Diesel, Greencastle, Pa." sign above the timing lights. I lived in Greencastle for 4 years.
Posted on: 2016/10/12 14:01
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Every man dies but not every man lives.
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rklessdriver Re: 10-09-2016 MPC Real Street race
Senior Guru
Woodbridge, VA
1310 Posts
Member since:
2008/1/4 0:00



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I was looking through all the photos just now and I noticed that the car actually picked the front end up about 1ft before it started rattling the tires in Q1.....

https://bandbphotos.smugmug.com/KOTT-MPC-REAL-STREET/i-rjwvGt2/A


That is very interesting. I couldn't tell the car did that from the drivers seat. I thought it went into tire shake almost immediately.... Had I seen that pic or if someone would have taken a video of that pass I would have taken some power out early and likely avoided the whole huge wheel stand in Q2.

The crazy thing is.... the car was doing this stuff on only 10* of timing. It's going to take an entire different approach with the Progressive Controller to get it down the track with the timing up to 16*....
Will
Posted on: 2016/10/12 16:08
_________________
1984 Corvette. 434 SBC with a Powerglide.
Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials.

1972 Corvette. LS5 454 BBC with M20 4 speed.
Best Pass - Doing good to just pass a gas station.
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rklessdriver Re: 10-09-2016 MPC Real Street race
Senior Guru
Woodbridge, VA
1310 Posts
Member since:
2008/1/4 0:00



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Interesting discovery last night while checking general ignition things out....

My distributor rotor was held on by one screw.... My MSD Pro Billet distributor has a big cap conversion that uses a big Ford style cap and the bubble type rotor.... Well one screw was tight and the other screw as sitting in recess of the rotor not even threaded in...

The rotor wasn't moving around on the top plate that I could tell, but I bet that screw jumping around in there could have caused some misfires...

Have to wonder how that happen and how long it's been like that.

Also the top plate on my MSD distributor is pretty loose and that will cause the timing to move some - Which BTW it does... it backs up about 2* as RPM increases. Now I have to go back and tighten up the nuts that lock the advance mechanism up.

Will
Posted on: 2016/10/13 18:33
_________________
1984 Corvette. 434 SBC with a Powerglide.
Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials.

1972 Corvette. LS5 454 BBC with M20 4 speed.
Best Pass - Doing good to just pass a gas station.
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BillH Re: 10-09-2016 MPC Real Street race
The Stig Moderator
Reno
22702 Posts
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2007/12/25 0:00



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Glad you found it Will.

The MSD OptiSparks have had that problem too, lot of posts on the web about it.
Posted on: 2016/10/13 18:54
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