[jthomp1256]

I got a 468 mild cam 4 speed car,that is fouling plugs like crazy,about 9.5 if i was guessing i run 93 octane with no pinging or knocking of any kind as a matter of fact the car runs real strong,,it does surge some in 1st gear,,,,,timing is set at 38 degrees at 3000 with a vacume advance,,here is the kicker though it only has about 6 degrees initial,it has an adjustable vacume advance but have never fooled with it.

I know you should have ruffly 18 and 18 but how do you get there??
Jeff

carb seems to be set right

 

[Jerry70]

What kind of distributor? 38º @ 3,000 WITHOUT vacuum advance is good, but with va is way too low. Have you confirmed that your total is all in by 3,000? If not, checking it at that rpm is useless. Recurving involves changing the advance rate (how fast it advances and what rpm it peaks at) and amount. Springs control the rate and, in most distributors, a bushing controls how much.

 

[jthomp1256]

yes used a snap on timing light definatly in by 3000 not sure of brand looks like msd but isnt got on ebay timed with vacume advanced pluged but i am useing manifold vacume whem plugged in i have no porrt vacume

 

[69-CHVL]

If you have alot of free time on your hands, install a "Stop bolt", and adjust the amount of mechanical that you want by grinding the side of the bolt. All trial and error. Right now I have a 16* curve.

PS, for reasons I cant explain - maybe somebody can enlighten me - when you shorten the mechanical curve, it comes in alot faster. So you will need the heaviest dizzy springs you have - and its still gonna come in fast!

You may need to whittle a bit of plastic off of the rotor to get it to sit down properly now that the bolt is in the way.

 

[SWHEATON]

Jeff,if your runing a perf cam & you have a few extra bucks and dont mind laying up the car for a few days send the dist out to a shop and have approx 18 deg mech adv set in dist in by approx 2800 rpm to run with approx 18 deg base timing for total of 36 in by 2800.

That should be a decent setup aong with a vac adv that give approx 14 more deg timing thats fully activated at 2" below lowest ilde vac with auto trans in gear with 18 deg base timing.

Your motor should feel like a rocket in lower rpm range below 3k rpm when you go from 6 deg to 18 deg base timing ,the throttle responce should be greatly improved as will be fuel mileage and motot will run a little cooler at idle in traffic and when moving slow at like below approx 2800rpm when the mech adv isnt fully in yet.

Make sure to have vac adv unhooked/plugged when setting base timing and ilde low like 600-650 rpm too and re-attach the vac adv when done & also reset idle mix & speed too post timing adj.

But if your patient & good at tuning like Vince is then try what he suggested and see if you can get it done yourself.

Scott

 

[jthomp1256]

Scott anywhere close to ohio that has a machine that will recurve one Jeff

So if i get wht Vince is saying is that my distributor is opening to far or not is realeasing to much?

 

[SWHEATON]

JEEF,This person ( Jerry MacNeish )is the closest that i know of thet recurves dist,i have had him restore/rbld/recurve 2 dist in the recent past and he did a very good job on them.

You dont have to restore your dist,just tell Jerry what you want done and he can do it. Check out his site to see that type work he does,very impressive repair work on broken intakes and ex manifolds and he can resto/rbld just about anything. I also had Jerry restore my original master cyl with SS sleeve,came out very nice.

I also listed 2 more place that can do it below Jerry so you have more options.


Scott

Camaro Hi-Performance
c/o Jerry MacNeish
5750 Kinsmen Courage Ct.
Eldersburg, MD 21784
E-Mail: Z28CAMAROMAN@JUNO.COM
======================================================
Dave Ray
(775) 463-1821 (Shop)
(775) 463-1809 (Fax)
sparkman451@earthlink.net Dave's Small-Body HEI's
24 Buffalo Lane
Yerington, Nevada, 89447
http://www.DavesSmallBodyHEIs.com/

=======================================================
FBO Systems
541-942-5920
Distributors Rebuilt, Curved and phased http://www.4secondsflat.com/Ignition.html
Phone-410-781-0418

 

[jthomp1256]

scott i found out this is a chinese distributor,, is this even worth fooling with Jeff

 

[SWHEATON]

All i can tell about the asian stuff is that i see here in t/chevelle much ofit is junk but i have no exp with it,sorry about that.

But i am sure somene else will chime in to give their exp with it.

Scott

 

[Dave Hopkins]

Rule 1 is you want zero activiy from mechanical advance at idle speed! So mechanical wants to start at say 1100 RPM. That will take some fairly strong springs.
Rule 2 is you want it to move smoothly. That works best if one spring is stronger than the other.
Rule 3 is you the centrificle all in by 2800 and that should be around 18 degrees.
38 degrees total is way too little, 38 initial + centricle sounds about right, then add vacuum. Mine (.070" over 454 with 9.6 to 1 compression and mild hydralic roller) is very happy with a total of 60!

 

[SWHEATON]

Jeff,Dont do this (38 degrees total is way too little, 38 initial + centricle sounds about right, then add vacuum) as suggested above because it's the wrong thing to do with the mild cam you say you have in your bbc.

Most setups like yours like 18 deg base timing + 18 deg mech in dist for approx 36 total + 14deg vacuum adv for 50 with everything in.

Make sure to unhook/plug vac adv and idle motor low like 600-650 rpm when setting/checking base/totaltiming.

Maybe a hotter cam like in Dave's case could use a little more timing but not a mild cam'd 454 on pump fuel like in this case.

Scott

 

[jthomp1256]

Scott thanks alot i did my distributor my self and all i can say is unreal,,its a brand new car the power at take off is unreal,,i can only imagine the amount of guys out there that has the wrong set up in there distributor and they dont know what there missing!!!!! 69 CHVL i used your pick and it was a great help ,thanks to all who responded Jeff

 

[SWHEATON]

Jeef,glad to hear you got you motror running up to it potential now with the improved base timing & timing curve.

Since you started at 6 base what did you end up setting the base timing & mech adv in the dist so that it ran so well with a lot more umph!!!!

Was it approx 18 base & 18 mech for 36 total along with the vac adv hooked to full intake vacuum?

I just wanted you to clarify the timing you ended up with that had such good results comming from the 6 base you started with running a farily hot perf cam so others having issues like your can see where you started and what it took to get it squared away.

Scott

 

[jthomp1256]

Scott right at 17 and a total of 39 before VA ,,when i had my 540 in my race car with 14.9 and 750 lift cam i did run closer to the 55 degree locked before nitrous and with nitrous th retard would take it closer to 33
8.60 @ 165 in a 3100 lb Pontiac phoenix

but this is a first for me with a 4 speed stocker type motor i always said it didn't feel right but coming off the 540 i didn't know what to expect but this is a real treat ,,,, it almost felt like before that you were starting off in secong gear all the time and now its hard to start of in 1 st without the tires chirping with only 331 gears with an m 2o its cool thanks Jeff

 

[SWHEATON]

Jeff,thanks for the info so everyone can learn from it and glad the 468 still has enough kick after getting the timing squared away for you to have some fun comming from a 540 to a 468 streeter with 331 gear & m20,sounds like a fun setup to me.

I run a mild 396/ now 402(approx 370hp/440 lbs trq with 331 & m20 and it gets out of its own way pretty decently so your 468 should kick pretty darn good for the street with same setup as my car but with more cubes & power/trq.

Have fun.

Scott