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No, 35(total)-22(mechanical)=13 initial. However, with that said these engines like more than 35, I would shoot for 38 and start with 16 initial.
 

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So if I wanted 35 total my base should be 23? My light at home is apparently crap at this point so I’ll need to go to the shop and use a “quality” one. 23 sounds a little high for base. Sorry guys but I’m an idiot when it some to tuning old school stuff.
If the distributor has 22 mechanical, you want 13 degrees of initial to get to 35 total w/out vacuum advance connected.
 

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Discussion Starter · #23 ·
🙄 Of course. Brain fart here. Yes, 13. Well I’m sure that I’m close to that but I’ll have to double check. Is there any concern with putting the distributor in right out of the box? Did I miss something?
 

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🙄 Of course. Brain fart here. Yes, 13. Well I’m sure that I’m close to that but I’ll have to double check. Is there any concern with putting the distributor in right out of the box? Did I miss something?
You can get the advance kit that's advertised in the instructions and just use the springs to bring the curve in earlier.
 

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AR3934 plugs? Are you running a ton of nitrous? If not, then those plugs are way too cold!! They will foul in short order no matter what you do. They are equivalent to a NGK R5671A-8. 8 heat range and non projected tip.
Do you have aftermarket heads? As those plugs are 3/4" reach gasket seat.
For 10.5:1 and lower compression, and a 3/4" reach plug for no nitrous use, you should be using a BKR5E or Autolite AR3924.

Your streetfire HEI has 22 degrees of centrifugal advance in by 4000 rpm. You will need to get the advance kit 8428, and install the light springs to have your advance in soon enough, before 3000 rpm. All you will use from the kit are the springs. This will give you 24 degrees of centrifugal advance, which IMO for your cam will not allow you to run enough timing at idle. That is why I said to get the advance lock out plate kit. But, try it I guess. 14-16 degrees advance at idle is not going to be most efficient with that cam. Hopefully you make enough vacuum at idle in gear to pull the vacuum advance cannister in all the way and can then hook it up to full manifold vacuum. If you do, then you will be ok not locking the dist out.
You also need to install the vacuum advance limiter plate that would have came with the dist, part 84281. Set it on position B, for 11-14 degrees. That is the most advance I would want it to be adding.
 

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Discussion Starter · #26 ·
AR3934 plugs? Are you running a ton of nitrous? If not, then those plugs are way too cold!! They will foul in short order no matter what you do. They are equivalent to a NGK R5671A-8. 8 heat range and non projected tip.
Do you have aftermarket heads? As those plugs are 3/4" reach gasket seat.
For 10.5:1 and lower compression, and a 3/4" reach plug for no nitrous use, you should be using a BKR5E or Autolite AR3924.

Your streetfire HEI has 22 degrees of centrifugal advance in by 4000 rpm. You will need to get the advance kit 8428, and install the light springs to have your advance in soon enough, before 3000 rpm. All you will use from the kit are the springs. This will give you 24 degrees of centrifugal advance, which IMO for your cam will not allow you to run enough timing at idle. That is why I said to get the advance lock out plate kit. But, try it I guess. 14-16 degrees advance at idle is not going to be most efficient with that cam. Hopefully you make enough vacuum at idle in gear to pull the vacuum advance cannister in all the way and can then hook it up to full manifold vacuum. If you do, then you will be ok not locking the dist out.
You also need to install the vacuum advance limiter plate that would have came with the dist, part 84281. Set it on position B, for 11-14 degrees. That is the most advance I would want it to be adding.
Thank you for the info. I am having exactly that problem with the plugs, I suppose i was recommended that plug because it is “safe” or they were just out to lunch. They are older Eddy’s RPM performer heads, 64cc and right at 10.25:1, KB hyper flat tops. Been running 93 fuel. No power adders on this thing. I appreciate the part numbers and what not. I’ll double check base timing again and go from there. It runs pretty good but I just know there is more there not to mention the terrible stumble when you just mash the throttle from a cruise. Actually if you just stab the throttle and hold it to the floor it’s like you just turned the key off and most of the time it will not recover unless you let off and feather it or kind of do a stab, stab then mat it, it will rip pretty good once you get past that issue. I got rubber the other day going into third at 60 or so 😁. It sounds good and clean from a stop with a full wide open pull. Just to see the outcome I’ve held it to 7K and it never broke up or anything although I know that’s pretty well past it’s numbers.
 

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Thank you for the info. I am having exactly that problem with the plugs, I suppose i was recommended that plug because it is “safe” or they were just out to lunch. They are older Eddy’s RPM performer heads, 64cc and right at 10.25:1, KB hyper flat tops. Been running 93 fuel. No power adders on this thing. I appreciate the part numbers and what not. I’ll double check base timing again and go from there. It runs pretty good but I just know there is more there not to mention the terrible stumble when you just mash the throttle from a cruise. Actually if you just stab the throttle and hold it to the floor it’s like you just turned the key off and most of the time it will not recover unless you let off and feather it or kind of do a stab, stab then mat it, it will rip pretty good once you get past that issue. I got rubber the other day going into third at 60 or so 😁. It sounds good and clean from a stop with a full wide open pull. Just to see the outcome I’ve held it to 7K and it never broke up or anything although I know that’s pretty well past it’s numbers.
Yes, your plugs are way too cold. Replace them with either I listed. Then get the timing set up right. You need a timing light and preferably put a timing tape on the balancer.
Then for the carb, ensure floats are mid sight glass (if it has them) or fuel at the bottom of the threads when you take the fuel plugs out. What list number on the carb?
Then check that the accel pumps are adjusted properly. Lengthen the bolt with the spring on it, until at full throttle you can slide a .015" feeler gauge between the head of the bolt, and the accel pump arm, without making the spring compress on the bolt. What you want is a slight bit (.015") of travel left in the accel pump diaphragm at full throttle so it doesn't damage it. Many people think the .015" is a gap at idle, which is wrong.
 

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Discussion Starter · #29 ·
So I changed the plugs tonight since I had a few minutes, number 3,4 and 5 looked like they have been running pretty dang lean to me. For what is worth the last time I drove it was about a nine mile cruise home from town , runs about 3,200 at 60mph or so and drove it right into the garage and haven’t started it since. That was the last run on the plugs. I checked the number on the squirters and they are a #28.... suppose that is a little small? 65/73 on the jets. I didn’t want to wake everyone up tonight to get it up to temp and check the timing again but that will be my next step before ripping the carb apart, but after looking at plugs I’m beginning to think things are a bit lean. Perhaps the blubber I hear at about 40mph is actually a lean one and not a rich one? If I was smart I’d just put an air/fuel sensor on the dang thing and make this entire process a whole lot easier! 🙄 Can’t fix stupid. I’d just really like to educate my brain on this little demon before I assemble the new motor so I know right where to head when I encounter an issue like I’m having now. Plugs look lean but damn, my ear and nose tells me it’s rich. I’d like to see some tan on them but a couple are flat out white. Maybe it’s just a distribution issue with the intake on a couple cylinders.....who knows. Timing is next either way.....probably try bigger squirters too just because it’s a simple change.
 

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67/73 are stock jets, and 28 squirters are stock as well. High rpm cruise, the plugs should look very clean, and for color you look down inside at the bottom of the porcelain. Not the tip.

Confirm float levels are correct, and what is your fuel pump/fuel line/filter set up?
 

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Discussion Starter · #31 ·
So the first thing I did was drilled the squirters out to .032 from .028 to see what it would do, that helped the bog a ton but didn’t want to go any more until I rechecked the timing. So I just did that, drove the car up to temp, pulled the vacuum line off and plugged the port, readjusted the idle to 800 ish and according to my “good” light it was advanced pretty far, better than 20 degrees anyway. I set it to 16 base plugged things back in and readjusted the idle and went for a drive. The bog is nearly gone but now it just feels down on power. Could I have the wrong balancer on this thing? The timing marks are roughly 12 o-clock and it’s an 83 block, the motor I pulled out of the car was a 78 I believe, oil dipsticks are on opposite sides. It’s just mind boggling to my pee brain. Main jets are 65/73. With colder weather and more timing it sure seems to run better, like 30-50 better by my butt dyno. It’s abour 70 today other than the big issue it seemed to run really good at 45-50 degrees and more timing.
 

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You have the std timing tab on it? Or do you have the tab that is viewed from behind the water pump?
If you have the balancer that has the tdc mark at 12 o clock, but the tab that is used for the balancer with TDC at 2 o clock position, your timing will read 30 degrees more than it actually is.
Or if your balancer ring has slipped, you need to verify true tdc.
 

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Discussion Starter · #33 ·
It has the balancer and tab for the “12 o-clock” position. I will certainly be verifying tdc for sure because it just seems like something is fishy. I also need to verify that the distributor is actually giving me 22 degrees advance because I can literally twist the distributor probably 10 degrees advance (if we’re speaking of a 360 degree circle) and it runs a lot better. If everything is working correctly it should be way over 50 degrees advanced at wide open I’d think! It should be a detonation monster if that was truly the case.
 

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It has the balancer and tab for the “12 o-clock” position. I will certainly be verifying tdc for sure because it just seems like something is fishy. I also need to verify that the distributor is actually giving me 22 degrees advance because I can literally twist the distributor probably 10 degrees advance (if we’re speaking of a 360 degree circle) and it runs a lot better. If everything is working correctly it should be way over 50 degrees advanced at wide open I’d think! It should be a detonation monster if that was truly the case.
Get the advance curve kit and put some lighter springs in it.
 

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Discussion Starter · #36 ·
So here’s a little update to the situation. As I stated before I had “28 squirters and drilled them out to .032” and that made a pretty noticeable improvement, still not perfect but better. I set the base timing at 16 btdc and kinda felt like a pooch according to my highly tuned butt dyno. I did verify tdc on #1 cylinder with timing marks and that’s all good. So just as an experiment I found some lesser springs out of an old excel distributor I had laying around. I threw those in the MSD and we took off on a road trip. After about ten miles or so I layed into it and holy crap, someone dumped a bunch of marbles in the cylinders.......detonated like a mutha, first time I’ve had that happen even with all the messing around I’ve done with it. Stopped for gas and gave the distributor a bit of a clockwise twist and then we put on 360 miles....from Lake Huron to Lake Michigan and back. I thought that I could just hear a little rattle once in a while at wot through out the day but left it where it was, I haven’t yet rechecked timing to see where it ended up. It was really hot here Thursday during our road trip. Obviously the weaker springs with stock weights was allowing for way more advance. Still a little blubber at low speed 35-45 ish and a little bog when you stab it. Any thoughts on these developments? Lust a reminder this thing has 4.10 gears and a 28” tire so it not like I’m loading the engine with a 2.55 gear or anything.
 

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With the hei you cannot just put lighter springs in without checking the total advance. There isn't a positive stop like a MSD dist has, the plate rotates until the weights reach full extension, the amount of which changes with the springs used.
I would also just install lock put plate 88363, set the timing to 38 and send it.
 
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