.030 overbore raises compression. Surfacing the block to clean it up, and looking back at your pictures of heads they look milled also. All raises compression. Iron heads don't usually like more than 9.5 compression on pump gas.
This test was before I replaced the bad valve seals and while the engine was burning a LOT of oil that caused the carbon buildup. Should be interesting to compare now.
Do you have a AFR meter? Maybe your carb is lean? Most engines like around 13 to 1 at idle, 15 to 1 cruise and 12 to 1 full throttle.
So theoretically if I do actually have higher compression....... would retarding the cam gear as suggested result in better performance compared to the 0* or straight up cam gear with a race fuel mixture?
Your peak TQ and HP will move up about 500RPM from before and your Dynamic compression will drop from about 8 to 7.5. You would lose a little on the low end and gain on the top end. Without the detonation it would feel better throughout the range. Do an ET and compare from before.
Hi Ron, late to the discussion! Quick answer, no. Knowing the actual cam to crank timing is a must, so don't just change it for the sake of experiment. Measure it first so we know where you are. From what I've read right here on V8, your Silvolite flat top V6 pistons should be giving you less than 10:1 static compression ratio. That shouldn't be a problem with pump gasoline. Can't be sure where to go next without measuring things. Devon
If your cam has 4 degrees advance built in, straight up is already 4 degrees advance. So when you retard it 4 degrees you are really zero or straight up. If you put it on 4 degrees advance you are really 8 degrees advance.
My understanding is my 284-88h cam doesn't have any advance built in. I installed straight up and my dial indicator showed equal overlap at #1 tdc. Please correct me if I'm wrong.
It turns out that my balancer was fine. The discrepancy was due to the wrong timing indicator installed on my timing cover. It was for a v6. I replaced it with correct one in August of 22.
The first one on mine was for a v6 and 8* off i believe. Compare your number placements to my v6 indicator. It was misleading me for over 35 years.
I talked with Mike at TA this morning. He said the cam has no advance ground. He is thinking carb is too lean. He thinks my compression should be about 9.5 with my modifications. He says my car is a dog if it still runs 15s in the 1/4 with this combination. Should be noticeably better. He said it would be hard to say what a compression gauge should read with this cam but I plan on doing it soon. .......Does anyone have this cam that ever did a compression test?
Compression test revealed 175-180 on all cylinders. Middle plug pictured is ur5 that was in #4 cylinder. outside ones are ur4. I was going to check the ur5 in #4after a few 100 miles. I forgot. Other 7 were ur4. .......I'm thinking replace all with ur5 plugs. Here's all.
