Fixing over compression on a 2FE (Camshaft analysis?) (2 Viewers)

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Thanks for the input. I forgot to mention in my original message I have a DUI distributor with livewires. Does this change anything as far as retarding the timing by moving it clockwise? Also, I run 91 octane or non-ethanol fuel at about 4500' above sea level.
There seems to be a lot of people having trouble with those distributors. At least from the many threads that come up on here
 
You are right. Same boat as me. Yep, retard 1° at a time until it goes away. I have the MAF HEI, I don't know what the advance curve is, or if they are all the same, but it seems to work well for me at 11° idle @ 4000ft.
I don't have a timing light so can I just rotate ever so slightly, tighten, test drive and repeat until cured? Or is this something that requires a good timing light?
 
The machine shop planed both the head and the block. I was prefitting everything and without the head gasket the pistons would lift the head. I'm not sure if this is normal or not but I think im gonna run a higher octane from now on.


I think some power would come of it, it would make sense to me.
If you planed the head and decked the block and the pistons were lifting the head it sounds like you may have a lot higher compression than you may think you have. I’d be wondering how close your valves are to the tips of the pistons during operation. How thick was your head gasket?
 
I don't have a timing light so can I just rotate ever so slightly, tighten, test drive and repeat until cured? Or is this something that requires a good timing light?
You can do it that way but a timing light is ideal.
 
There seems to be a lot of people having trouble with those distributors. At least from the many threads that come up on here
I've had my share.. bushings instead of bearings and improper lube for one.
 
I don't have a timing light so can I just rotate ever so slightly, tighten, test drive and repeat until cured? Or is this something that requires a good timing light?
Hahahaha! There are many ways, but an advance-able light from O'Reilly's is about $120. It's by far the easiest away. The whiskey glass technique is way cool, but better check your homework with a timing light. It's not like there are $2000 motors laying around in every junkyard. But yes you will do it that way with a light or not.
Amazon product ASIN B000EVU8J8
 
You do not want a higher compression than 9:1 for pump gas. Too much compression will cause detonation regardless of timing. Did they CC the head?
No idea, they seemed pretty reputable based off of online reviews.
In an old engine. Modern engines are all up in the 10:1 or high range and run fine on pump gas.

bun an old design like this it’s probably a good idea to not get to crazy
Im not trying to get crazy i just want to drive to school :frown:
And exhaust pops going down hills.
Does your exhaust pop too?



So I ended up reseting the EFI computer because why not, After some hard stumbling she came back to life. I have the timing set back quite a bit now and the clacking has seemed to vanish, and the exhaust pops on deceleration have returned. I have 10,500miles on the rebuild with new pistons so hopfully any catastrohic failure would have occurred by now. I guess i'll try a true higher octane fuel next time around and see how far I can set the timing without that dreaded clacking.
 
I wouldn't worry about exhaust popping to much on a deceleration or down hill on a modified old engine like these.

You could install an Air/fuel ratio gauge and a vacuum gauge to help you fine tune it over time. Tracking your gas mileage is a good idea.
 
I wouldn't worry about exhaust popping to much on a deceleration or down hill on a modified old engine like these.

You could install an Air/fuel ratio gauge and a vacuum gauge to help you fine tune it over time. Tracking your gas mileage is a good idea.
I already have a vacuum gauge, it sits at 15hg at idle.
I might get an air/fuel gauge for giggles and :poop:
 
No idea, they seemed pretty reputable based off of online reviews.

Im not trying to get crazy i just want to drive to school :frown:

Does your exhaust pop too?



So I ended up reseting the EFI computer because why not, After some hard stumbling she came back to life. I have the timing set back quite a bit now and the clacking has seemed to vanish, and the exhaust pops on deceleration have returned. I have 10,500miles on the rebuild with new pistons so hopfully any catastrohic failure would have occurred by now. I guess i'll try a true higher octane fuel next time around and see how far I can set the timing without that dreaded clacking.
You might check the paperwork or get in touch with them about the compression ratio. People have had too much shaved off and we're SOL. Based on what you have said, I don't believe this is your problem except to part about the head not fitting without the head gasket.
 
You might check the paperwork or get in touch with them about the compression ratio. People have had too much shaved off and we're SOL. Based on what you have said, I don't believe this is your problem except to part about the head not fitting without the head gasket.
I doubt contacting them would go anywhere, They didn't install a welch plug properly so it fell out and dumped oil. It was way quicker and cheaper to fix myself so thats what I did. and Its been well over a year so any "warranty" is gone. I didnt specify alot of things and the valves were cut wrong, etc. But its ran fine for 10k miles.

Im at a point in time where I cannot afford to undergo any catastrophic failures. This is my daily car and it has to take me to school every day now. There is no backup car and there is no backup funding. University has drained me dry.
 
Valves cut wrong..? Now I'm worried for you! This is the reason we go to a machine shop instead of doing it our selves.. did they fix it?
 
Who else remembers FJ40Jim talking about the later big cap distributor centrifugal advance over-advancing problem? It was caused by the rubber covered pins that limited the advance weight travel. The rubber crumbled off over time allowing additional advance, making total advance ( centrifugal + vacuum) excessive.
 
Who else remembers FJ40Jim talking about the later big cap distributor centrifugal advance over-advancing problem? It was caused by the rubber covered pins that limited the advance weight travel. The rubber crumbled off over time allowing additional advance, making total advance ( centrifugal + vacuum) excessive.
is there a thread you can link to? My timing doesnt chatter untill ive been driving for 10+ min. Sometimes It wont start clacking until and hour after driving
 
Who else remembers FJ40Jim talking about the later big cap distributor centrifugal advance over-advancing problem? It was caused by the rubber covered pins that limited the advance weight travel. The rubber crumbled off over time allowing additional advance, making total advance ( centrifugal + vacuum) excessive.
The stop pin bushing can be replaced with a nylon or aluminum equivalent - 1/4" OD X 1/4" length sized for a #8 screw.
 
Who else remembers FJ40Jim talking about the later big cap distributor centrifugal advance over-advancing problem? It was caused by the rubber covered pins that limited the advance weight travel. The rubber crumbled off over time allowing additional advance, making total advance ( centrifugal + vacuum) excessive.

The stop pin bushing can be replaced with a nylon or aluminum equivalent - 1/4" OD X 1/4" length sized for a #8 screw.
Is this for the FJ60 dizzy exclusively? I have an Fj62 dizzy. Im gonna pull the cap tomorrow to look anyways. Yaknow a library of pictures of every single engine part would be really helpful. I think if I ever rebuild my engine again Im gonna try and photo document every engine component and put it into one library.
 
Well it's been hot outside. High ambient temps give higher intake air temps which makes a motor more prone to Ping. Since you have higher compression than stock, I would recommend a higher octane during warm times of year. Iron cylinder heads are more prone to have hot spots in the combustion chamber so they are more sensitive to higher compression ratios. A snorkel would give you cooler intake air temps if you want to try that. You can also try setting the base timing a few degrees more retard in the summer. If it's pinging while towing then you should run higher octane when towing. Towing also induces pinging more. Pinging causes a loss on power and its hard on the head and pistons. So it needs to be addressed.
 

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