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69Pony
06-11-2007, 09:11 AM
Guys,

Having a problem with what I think is electrical issues.

MSD 6AL
MSD ready to run billet dizzy
NGK plugs
MDS 8.5 wires

Initial timing at 16* / 34* total with the two light blue springs so it is all in around 2600rpm.

Car starting fine (18* initial makes it a hard start). Good idle at 950.

However, between 3-4k I get choppy acceleration and really flat power band. Almost feels like the rev limiter but it's a 6200 chip and is working.

10.7:1 compression with plug gap at .040. Thinking about bumping that to .045-.050 per MSD.

Any other ideas?

Thanks,,,,,

6'9"Witha69
06-11-2007, 11:03 AM
Cam specs with installed centerline please.

69Pony
06-11-2007, 12:48 PM
Sorry... I'm going to put this in my sig. until I can get my problems fixed.

351 Cleveland stroked to 408
Pro Systems (4150 style) 950cfm mechanical carb 71P / 78S
all hydraulic
Comp Cam
duration @ .050 240 / 244
intake lobe lift .360 / .363
1.7 rockers
valve lift .622 / .627
10.7:1 compression
16* initial ' 34 * total timing at 2700rpm
NGK plugs .047 gap
MSD Pro Billet dizzy, Blaster II, MSD AL6

chicane67
06-11-2007, 02:41 PM
That sounds like a grounding issue... or your timing is coming in to fast/slow for the timing needs.

69Pony
06-14-2007, 09:38 AM
I was thinking a ground issue also but it does have new 8.5mm MSD wires and I was careful to not route 5 and 6 next to each other. Notorious arching can happen in a Cleveland with 5 and 6 since the firing order is 1 3 7 2 6 5 4 8. I wonder if I am arching onto the metal shaker scoop base? Easy check on that by removing it. I've also had grounding issues in the past with the negative ground to the block. Basically no start up with that issue though.

I don't think it's timing coming in to slow - if anything a tad fast.

hectore3
06-15-2007, 06:26 PM
Check under the MSD dizzy cap for any corrosion and clean and apply dielectric grease as needed. MSD has had issues with this. Just a thought.