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Discussion Starter #1
I have a 327, 10 -1 milld crane cam,1.92 valves, new Edelbrock 600 cfm carb,new Edelbrock air gap intake,new MSD billet dist [no vaccuum advace],new MSD 6AL box,new MSD blaster 2 coil ,new MSD solid core wires,new AC Delco plugs,new holley fuel pump [5 psi].The timing is 18degrees initial advance and 37 total.When I first tromp the gas it hesitates[kinda dies] then revs good to red line.So far I moved accelerator pump rod closer to carb[didn,t help]then I purchased new squirters from Edelbrock.The ones in there were 32 and I installed the 43,s. Same thing..same stumble. Please help.Anyone have any ideas?
 

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Tuning Guru??

Hey Now chevynuts88. The problem is not in the accelerator pump. The area is in metering rods and jet size. Spring tension that raises and lowers the metering rods according to engine vacuum. The description indicates lean condition at hit of the throttle. First try metering rods or jets that richen the mixture just off throttle. This might be just a jet change or metering rod change, but it could be both. Sincerely, "Bill's" II
 

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So far I've tried about every combo of springs, metering rods, jets, air door in and out of carb, spent time on phone with Edelbrock tech---still falls on it's face....sometimes! One hit it'll take off; the next time you peel your face off the steering wheel!! I've never been a big fan of these carbs, and this one isn't making me feel any better about them. Steve Magnante puts them on all his projects and he loves them--of course none of his stuff goes very fast either, but.............
 

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One thing I'll add here is that street cars in my experience should always have a vacume advance on the distributor. Full mechanical advance works on strip cars (and I realise your telling me it dumps on hard excelleration) but for the real life driving situations most street motors like or benefit from losing some initial advance on excelleration (especially if you have a 355 or higher gear ratio) Also, I've seen motors that like no vac advance at idle, and vise versa. Maybe not your problem, but another thing to consider......
 

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Discussion Starter #10
no vacuum advance

I have a 327 with msd dist no vac advance .They say it has 21 * built in .Could that be too much intial advance?
 

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chevynuts88 said:
I have a 327 with msd dist no vac advance .They say it has 21 * built in .Could that be too much intial advance?
Carl are you sure that is intial and not mechanical advance that is built into that dist?
 

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Discussion Starter #14
Yes that is initial. Ive never had one like this before and I am having problems tuning it .It has an msd billet dist ,wires,ac delco plugs,blaster 2 coil,6AL box,650 edelbrock carb and air gap intake [all new].It also has a mild crane cam.It stumbles badly when you floor it from an idleand misses start at 4500 rpm.The distributor was out and the motor "bumped ". Maybe I have the dist out of whack.If I put the engine at tdc on #1 how do I tell "FOR SURE" the oil pump shaft is facing right and the dist is going in right?
 

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hmmm...I am a little stumped as to how they can actually build intial timing into the dist????? Since normally that is set by rotating the dist after it is installed?????:confused: But anyway:)

IMO...the car would work much better with a vacuum advance dist. but since you have the vaccumless thats not an option....Basicly you have to verify that you are indeed at TDC for #1 and not #6. When you are at TDC check the rocker arms for # 1 cylinder if they are both not in the closed position then you are at TDC for #6. You can also look at the rockers for #6 just to verify...the rockers should be opening the valves IF you are at TDC for #1 If the rockers are both closed on the #6 cylinder when you are at TDC you are infact at the TDC for #6 NOT # 1. If you discover that you are at TDC for # 6 just rotate the motor another 360 degrees and line back up with TDC again. This will put you are TDC for #1.

Then its just a matter of droping the dist in...IF it wont line up with the oil pump shaft you can back the rotor up one tooth at a time until the dist drops in....just turn the rotor in the direction it will turn one tooth at a time and keep a slight (very slight) downward pressure on it......when the oil drive lines up the dist WILL drop into place. What ever lug on the cap the rotor is pointing at that is the number 1 plug. Then its just a matter of wiring the plug wires on the dist in the correct order.

Now to make firing the car easier you can once you have confired TDC line.....the harmonic balancer up at 10 degrees advanced and then drop your dist in as described...that will make it much easier to start the car then it would be with the dist in at TDC.

I hope this helps ya out.

IMO your going to possibly want about somewhere around 12-15 (maybe slightly more) degrees of advance to get your total timming where you want it...it might take some experementation to get this right...:)
 

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chevynuts88 said:
That is mechanical .My mind and my fingers are not working together today! Thanks for the help!
what you will be looking for is somewhere between 34-38 degrees of total advance...so since you have 21 built into the dist the rest will have to come from your intial...just play around with your intial until you have the total timing that works best with your setup...maybe try 15 degrees intial (that would give ya 36 total) and go from there...

good luck:)
 

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Discussion Starter #19
Its working a lot better!

A friend came over and set the timing " according to the timing tab" at 40* initial. He is well aware that sounds rediculous but thats where it runs best.By the way, when I purchased the car the timing tab was welded to the timing cover at the 12 o, clock positon and now it is in the regular position where you normally see them[between 2 ad 3 oclock]. He replaced my squirters to a size smaller because " it smelled way too rich " and the stumble was considerably less.It still stumbles a bit when first flooring it, he suggests smaller primary jets and needles.Ive never changed jet sizes ,how much smaller should I get? Any ideas?
 

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chevynuts88 said:
A friend came over and set the timing " according to the timing tab" at 40* initial. He is well aware that sounds rediculous but thats where it runs best.By the way, when I purchased the car the timing tab was welded to the timing cover at the 12 o, clock positon and now it is in the regular position where you normally see them[between 2 ad 3 oclock]. He replaced my squirters to a size smaller because " it smelled way too rich " and the stumble was considerably less.It still stumbles a bit when first flooring it, he suggests smaller primary jets and needles.Ive never changed jet sizes ,how much smaller should I get? Any ideas?
FWIW about 20 years ago I had a motor that I could not set the timing on in the normal range (10-14 degrees). Any time I would get it close to those numbers the motor would run like crap and die. The only way I could get it to run was to have the timming WAY more advanced than normal...actually right off the timing tab...likely in the 40 degree range you are talking about...The problem for me, not saying that this is the case for your motor, but the problem for me was that the timming chain was 1 tooth off. I had to pull the front off the motor and when I checked the timing chain the dots didnt line up on the gears correctly...I had to move the chain one tooth on the cam and then reinstall the front of the motor and then I was able to set the timing properly at 10 degree advanced....Just a thought:)
 
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