I just thought my compression test results would be higher than 180 if compression was that high. Thanks again for your recommendations. It's worth a try.
Yes, 34 total is the highest I ever go. Usually 32 works best in my experience with similar builds. I see on the simulation your TQ and HP # are at lower RPMs. By retarding the cam they would move up and without detonation you could have 12-14 initial and limit total to 34 and make more power. On Chris'300 Stroker build he had 4 degrees advance on the cam and his numbers were low like yours. It also pinged with his 10.3 compression but not too bad as he has aluminum heads and they tolerate up to 10,5 usually. He retarded it 4 degrees and the peak TQ and HP moved up about 400 to 500RPM and made about 50 more HP on the Dyno.
Advanced timing from optimum doesn’t necessarily guarantee more power, ESPECIALLY if your not detonating as is. I’ve been thru this years ago, wondering why the engine didn’t “feel” strong, then I read Larry’s Power Timing thread. YES, Very likely!
I did also talk to Mike about retarding the cam to solve the problem but he said that would take low end power and move it toward top end..... I barely break the tires loose now. It would be a very interesting comparison retarding the cam!! 50 more hp would be nice Ok I will retard ignition timing a couple degrees and check 1/4 mile performance and compare to previous. ........Sorry, but getting back to cam degree: So if I would change the 3-way cam adjustment to the rectangular mark from factory dot setting. That would be 2* retarded correct? And would you think that might be enough? Thanks again
Awesome! Yeah, move it around, see if you made any difference. If not, then I would suspect you got your cam timing wrong with that gear/chain set. Way back I had an ‘82 Regal V6 that I did some engine work to, I had the same type 3 way crank gear, didn’t quite understand what I was doing as far as cam timing then, “cool, advance it 4 deg. this thing will ROCK!” Well it didn’t rock that great, long cranking times when warm, bottom end was soft, top end wasn’t bad, BUT, the big takeaway from this is it didn’t matter where I had the timing, it made no difference in performance. If I brake torqued it, it would fry the tire, I had a 3.42 8.5 GN rear in it. It was a sweet looking Regal, kinda miss it.
I talked to Mike at TA again and he suggested just exactly that!! Did you make a bushing yourself? For my stock distributor? Maybe an oval one?
This is similar to what I bought, same thing but not from this particular site, but their pretty much the same, these are stainless steel, mine are aluminum, no issues as the MSD ones I believe are also aluminum. I did have to do a tad bit of filing to make ‘em fit.
I'm embarrassed to say but I removed my distributor and the brass stop bushing was gone! Maybe happened during the rebuild. So my no bushing timing was 11 initial and 34 total. I added a bushing and replaced my original weights and did some test drives adjusting idle a few times. Seemed the best i can set is 13 initial and 32 total. No noticeable detonation w straight premium gas but thought the motor almost kicked back when I turned it off once. Maybe not. Performance seemed unchanged. We didn't get any data from old gtech meter on 1/4 mile this time for some reason. I'm very pleased and relieved the detonation is gone! Thanks everyone! Of course I'm still very disappointed in no noticeable change in performance. Doesn't seem to have the power it should. I will continue to adjust timing curves a bit. I could bump up timing a smidge and see if detonation comes back. Maybe the compression ratio guess is back down to 9 to 1. idk. Appreciate more suggestions. Thanks again
Try adjusting initial to highest steady vacuum and back down 2 degrees. Have you tried the stiffer springs?
Now you have the bushing in, you could probably go back to the medium springs. Probably best to do one change at a time though.
I warmed up the car plugged va and used vacuum gauge on manifold port at 650 idle. Best is about 27* advanced. This is initial idle and about 14 on my vintage gauge. I took it for a tiny ride and of course didn't step on it. It has excellent throttle response off idle. It didn't run on after key is off and started hot easily several times. I'm going to back off distributor of course now. I'm thinking I need a much larger advance stop bushing?
Try it with your vacuum advance not plugged. it will be lower, before it starts fluctuating. I should have said that before. Usually the sweet spot will be between 15 to 20 and you may have to back off around 2 degrees or so for hot start. I also always use manifold vacuum not ported. Then you have to set your idle speed down. It does sound like you need more initial.
I did both and they seemed about the same. Gauge on manifold vacuum. Va is on ported vacuum supply. My gauge could be off also.
Well, you can try like Mark and run 20 initial with larger stop bushing. If you had manifold advance to the distributor my guess would be around 15-17.
I swapped the 1/4" stop bushing for a 7mm bushing. Test drove and retarded enough to hear no detonation. Im at 17 initial 32 total all in at 2200rpm. Definitely an improvement in performance. Thoughts?
Try bumping up to 19 and 34. If it doesn't ping try 20 and 35. Also back down if having starting issues. You may need the stiffer springs and have all in at 3500.
