Sure, blame it on your daughter...
CK5
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1992 454 swap into a 86. (now changed to a 496)
- Thread starter warwgn
- Start date
Ok hopefuly this is the last time. I really like the pinstripe design on this try the best, I did clear on all the grey a few days ago and it worked perfect. I think the black will go down smooth and this should be it this time.
Can't wait to see the finished product.
Very nice!
Ooh that's hot.
That dash looks great installed!
y5mgisi
1 ton status
x2!
well been thinking about the stumble and popping all day, back to trouble shooting the engine.
ok so started playing with the timimg and was at 15.3 advanced, hook up vaccum and jumps to 23.5 or so. idled it down to 850. check a/f ratio and it is pegged over 18 which says too lean at idle. pull out the tool and turn out the a/f screws and it bounces around 15-16.5 and vacuum is sitting at a steady 14??
now gets weird, if I rev it up the vacuum goes up to 20 or more, thinking I need to plug it into a different location like on the manifold, but will get to that later. Still sounds like a miss too will not hold a smooth steady rpm at all, so got out the IR temp gage and start checking the exhaust and find a variance in temps. 1,3, and 7 were at 350-400 5 was at 260, 2 and 4 wer 450, 6 was 300 8 was 230.
I may have some bad plug wires so need to get new ones and want 45 degree boots anyway, so guess I will start with that. I deff got to get rid of the miss before anything and get my vacuum feed sorted out.
like I said it runs fine cruising at 2000 RPM, vacuum at 17, A/F sits at 13.5, and smooth as silk, until you mash it hard it stumbles and pops but if you ease into no problem. and idle is not good either. Oh I did put different springs in my mechanical advance but dont remember which ones so prolln need to try and find stock springs and put it back and go from there. Seems ported vacuum should be really low at idle and not change the timing much when I hook up the advance to it but it does. Need to mess with it more but seems I have a long way to go and several small issues combining to cause a problem.
any sugestions or insight?
ok so started playing with the timimg and was at 15.3 advanced, hook up vaccum and jumps to 23.5 or so. idled it down to 850. check a/f ratio and it is pegged over 18 which says too lean at idle. pull out the tool and turn out the a/f screws and it bounces around 15-16.5 and vacuum is sitting at a steady 14??
now gets weird, if I rev it up the vacuum goes up to 20 or more, thinking I need to plug it into a different location like on the manifold, but will get to that later. Still sounds like a miss too will not hold a smooth steady rpm at all, so got out the IR temp gage and start checking the exhaust and find a variance in temps. 1,3, and 7 were at 350-400 5 was at 260, 2 and 4 wer 450, 6 was 300 8 was 230.
I may have some bad plug wires so need to get new ones and want 45 degree boots anyway, so guess I will start with that. I deff got to get rid of the miss before anything and get my vacuum feed sorted out.
like I said it runs fine cruising at 2000 RPM, vacuum at 17, A/F sits at 13.5, and smooth as silk, until you mash it hard it stumbles and pops but if you ease into no problem. and idle is not good either. Oh I did put different springs in my mechanical advance but dont remember which ones so prolln need to try and find stock springs and put it back and go from there. Seems ported vacuum should be really low at idle and not change the timing much when I hook up the advance to it but it does. Need to mess with it more but seems I have a long way to go and several small issues combining to cause a problem.
any sugestions or insight?
So think I will start by getting new plugs, wires, and a new mechanical advance kit with all the springs and new weights and bushings, will put all that on first then start the process all over.
Set initial timing no vacuum at 10*, then see what is does, I can tune the vacum advance 2* at a time but will try to put total advance around 34*
then if it will finally idle smooth and hold a constant rpm I can start setting the A/F screws to obtain max rpm.
as for the vacuum readings I think it is just the cam I have does not produce a lot of vacuum at low idle?
Set initial timing no vacuum at 10*, then see what is does, I can tune the vacum advance 2* at a time but will try to put total advance around 34*
then if it will finally idle smooth and hold a constant rpm I can start setting the A/F screws to obtain max rpm.
as for the vacuum readings I think it is just the cam I have does not produce a lot of vacuum at low idle?
Vaccum advance has no effect on total advance.
Martin
Martin
100% correct so let me re prhase my statement....
I plan to set initial timing at 10* then will adjust my vacuum advance 2* at a time to dial in my idle RPM and A/F mixture. with my cam and lower manifold vacuum I may need to get a canister that comes on at a lower vacuum but will just paly around and see. I will try and put vacuum advance at 16 for total timing at idle of 26*, then adjust it up or down to see what happens. I will be using manifold vacuum and not ported for this.
then I will run it up to 3k-4k RPM and check total mechanical advance, 10* initial and what should be 24* mechanical for total of 34*if it needs more then I will have to bump up initial and turn down vacuum the same amount to keep idle happy.
I think I have read that some cammed big blocks like to be around 38* and sometimes higher but not sure where my 496 is gonna be happy.
My issue now is, one I am on ported vacuum which is a mistake and I did not know better, two I suspect bad plug wires maybe, and 3 need new spark plugs, 4 the springs in my distributor may need to be changed.
as I said I have a few small issues combining to make a big problem, but feel I am on the right track to get them all resolved now.
I plan to set initial timing at 10* then will adjust my vacuum advance 2* at a time to dial in my idle RPM and A/F mixture. with my cam and lower manifold vacuum I may need to get a canister that comes on at a lower vacuum but will just paly around and see. I will try and put vacuum advance at 16 for total timing at idle of 26*, then adjust it up or down to see what happens. I will be using manifold vacuum and not ported for this.
then I will run it up to 3k-4k RPM and check total mechanical advance, 10* initial and what should be 24* mechanical for total of 34*if it needs more then I will have to bump up initial and turn down vacuum the same amount to keep idle happy.
I think I have read that some cammed big blocks like to be around 38* and sometimes higher but not sure where my 496 is gonna be happy.
My issue now is, one I am on ported vacuum which is a mistake and I did not know better, two I suspect bad plug wires maybe, and 3 need new spark plugs, 4 the springs in my distributor may need to be changed.
as I said I have a few small issues combining to make a big problem, but feel I am on the right track to get them all resolved now.
I believe John (80'427) was over 40 degrees total, but that was on LPG.
Martin
Martin
I have my 489 BB set at 37 degrees at 4k with vacuum advance disconnected. Initial is at ~21 with vacuum disconected. Then I rehook up the vacuum advance it's at ~52 at cruise, and 36 at idle with full manifold vacuum. You may need to have slightly less initial if you get any detonation as my converter is somewhat loose. AS always, you can push it a little more, but either way if you get any detonation anywhere back it off a little at that range.
Also, full manifold vacuum is the way to go for driveability and effieciency/performance, but make sure your vacuum can is all in below your idle vacuum, or you can get erratic timing and potentially eratic idle. I use a hand vacuum pump to tune/test my vacuum advance curve because you can vary the vacuum at a fixed rpm (not including the rpm change from timing) and see what happens.
Also, full manifold vacuum is the way to go for driveability and effieciency/performance, but make sure your vacuum can is all in below your idle vacuum, or you can get erratic timing and potentially eratic idle. I use a hand vacuum pump to tune/test my vacuum advance curve because you can vary the vacuum at a fixed rpm (not including the rpm change from timing) and see what happens.
that is a good Idea!!
So sounds like I am dialed in just about right, it did not diesel at all yesterday which tells me I am better. Now just need to get the new wires, plugs, and mechanical advance rebuild and I will be good to go.
could not resist, I know it has a small miss and is not dialed in perfect but..............
I drove Subzila to work today!!! Was dark out when I left and is supposed to rain like hell today but I hope to leave early today to go to the dentist and get new crown on my tooth if it is in yet.
Anyway, more specs from the gages.....60Mph, 2400 RPM, 17Hg of vacuum, A/F ratio of 13.5, Oil press 47 PSI, Trans temp 125*, H2O temp 195*, Volts 14.5 V, and it runs straight and true even though I have not had it aligned yet. Overall I am happy with it, not thrilled because if I get on it hard it loads up and pops and stumbles so I am sure now that it has a bad plug wire somewhere. I just dont have the $150 on hand to order new plug wires and plugs and the advance curve kit so that will just have to wait till next week to get resolved. Until that time I just wont stomp on it and truthfully I wont be driving it much anyway, prolly just today.
My wife followed me to work in the Camaro since I only got the one seat in it right now, and she verified my speed is right on, got to love a programable speedo!! She said she could hear the radio when we stopped at a light, I had it at 30 to drown out the noise inside. All metal no insulation or carpet and the dang trap door for the fuel tank rattles like crazy, need to screw it back down before I go crazy.
Getting my semi annual bonus next payday so hope to buy new seats and start getting the interior put together so I can start hauling the whole family around in it, something the kids want way more than I do!!
I drove Subzila to work today!!! Was dark out when I left and is supposed to rain like hell today but I hope to leave early today to go to the dentist and get new crown on my tooth if it is in yet.
Anyway, more specs from the gages.....60Mph, 2400 RPM, 17Hg of vacuum, A/F ratio of 13.5, Oil press 47 PSI, Trans temp 125*, H2O temp 195*, Volts 14.5 V, and it runs straight and true even though I have not had it aligned yet. Overall I am happy with it, not thrilled because if I get on it hard it loads up and pops and stumbles so I am sure now that it has a bad plug wire somewhere. I just dont have the $150 on hand to order new plug wires and plugs and the advance curve kit so that will just have to wait till next week to get resolved. Until that time I just wont stomp on it and truthfully I wont be driving it much anyway, prolly just today.
My wife followed me to work in the Camaro since I only got the one seat in it right now, and she verified my speed is right on, got to love a programable speedo!! She said she could hear the radio when we stopped at a light, I had it at 30 to drown out the noise inside. All metal no insulation or carpet and the dang trap door for the fuel tank rattles like crazy, need to screw it back down before I go crazy.
Getting my semi annual bonus next payday so hope to buy new seats and start getting the interior put together so I can start hauling the whole family around in it, something the kids want way more than I do!!
You are putting carpet back in it, right?
Martin
Martin
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