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Discussion Starter #1
With my roller cam at idle I'm only pushing 9" with the can disconnected from the stock dizzy with a Crane Xri and 10" connected with the stock LT1 can (201-15) using manifold vacuum. Using 7mm GM wires and a MSD Blaster 2 coil and AC R45 plugs.

My initial timing is 16* with vacuum plugged and total with vacuum plugged is 36* @ 3000 rpm. With the can connected the initial is 19*. So the can is giving me 3* advance and the dizzy has 20* mechanical advance in it.

When I tried the B28 can my idle would rev up and down like a super charger and turned my plugs black and crap was coming out of the tailpipes. The initial timing with vacuum connected to the B28 can was 34* at idle. Then there's 20* in the dizzy. It wouldn't idle right so I installed the stock 201-15 can back.

My stock 4555 Holley has no ported vac fitting in case someone says to try it.

Q:
What do I need to do to be able to use the B28 can for a better idle and help my plugs at idle and keep my 36* total advance?

If I drop the initial then my total timing will drop thus affecting performance and I don't want to do that. Do I need to change my distributor springs to one med and one light? I currently have the stock springs and weights in the stock dizzy.

The AC R45 plugs are fouling a bit on the drivers side only. The pass side 2-4-6-8 are white/grey in color using Shell premium with 0% ethanol. My Holley is the stock 4555 780 cfm. I changed the Prim jets to 68's from the stock 70's, and the stock 76's are still in the rear. Power valves front and rear are 5.0 compared for the stock 8.5.

Cam is
Lunati Roller 20120121
Advertised Duration (Intake/Exhaust) 278/288
•Duration @.050" (Intake/Exhaust) 232/242
•Gross Valve Lift (Intake/Exhaust) .507"/.507"
•Lobe Separation 112
•Intake Center Line 108
•RPM Range 2000-6400

The car runs fine to 6,000 rpm except for the little idling issue. I've got it set to 800 rpm and sometimes it goes up a bit and sometimes down a bit.
 

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I would say fashion a stop for the B28 can so you can limit it to around 10 degrees or so. I don't know if you can make this one work with it but maybe:
http://www.summitracing.com/parts/crn-99619-1/overview/

If you want the full 16 then it looks like it's going to take dialing the initial back to 8-10, then figuring out how to change your mechanical weight stop or weight profiles to get the 6+ degrees back on the top end. Springs will only change the rate, not the total.

Adjustable can may be the way to go. Crane makes an adjustable can with adjustable rate and stop plate kit. However, they don't seem to provide specs for it anywhere. The Accel 31034 does at least have a chart:
http://prestoliteperformance.com/media/instructions/accel/ACCEL_Instructions_vacuum_advance_points_v8_31034.pdf

Either way I think the carb idle circuit and curb idle is going to have to be adjusted once you get the initial where you want it. Should be able to lean it out with the extra timing.
 

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I would think about pulling the stock dizzy and going with an MSD 8360.

You can dial in your total advance and curve with the weights and springs included.
 

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Oh by the way with the 34 degrees advance at idle it was most likely rich misfiring since the carb wasn't dialed back yet.
 

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Discussion Starter #6
Is that B28 can leaking ? Or do what Steiner is saying, even adjustable advance cans.

Do plugs get all dirty with the LT 1 can?
New B28 can, 1-3-5-7 plugs get dirty with 7 being the worst if I drive 30-40 mph. 2-4-6-8 are good-white/grey.

How about making an adjustable plate. Left red arrow on this persons example.
 

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Mark , if that's your dist, that's some ingenuity ,
Sounds like the can is doing its job , unplugging and plugging as advance bumps up 3°. What about just running less initial and then when advance kicks in, you are at 16 or so?

Now the richness or sooty plugs part tells me something about the fuel flow on left bank. Is this the bank that's further or closest away from the clys? I am thinking in terms of a divided phlenum on a dual plane intake.

Is this issue something you have had or did it just pop up?
 

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Discussion Starter #9
^^ no that's not mine^^. I was just showing an example of a plate to make. Remember there is zero vacuum at WOT so the vacuum advance can isn't in the picture, so if the can gives me 10* then at WOT I don't get that 10* back.

Mine is the stock points type that looks like. Here's an old photo.
 

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Discussion Starter #11
Now the richness or sooty plugs part tells me something about the fuel flow on left bank. Is this the bank that's further or closest away from the clys? I am thinking in terms of a divided phlenum on a dual plane intake.

Is this issue something you have had or did it just pop up?
Not sure what you mean about furthest away.
old photo

What I did was swapped out the 70 prim jets and tried 69's. I showed plug pics to my builder and he said the plugs still look fat. So I swapped in 68's the other day. The pass side are white/grey, but the other side is fat with carbon. The top of the GND strap is a little rough like sand paper.

Ya think the carbon is caused from driving between 30-40 mph with this cam? My builder also said to put another 1500 mi on the car to seat the 1st ring which is a low tension Moly ring cause the motor uses a bit of oil if I drive 3000 rpm and above. After the 1500 mi I'll have I guess 3,000 mi on the motor. Using 15w-40 Shell Rotella.

I don't know if the carb needs to be taken apart and cleaned and sprayed with compressed air or whether I still need to jet down the drivers side ONLY on the prim. Last resort I do have a 3310-2 Holley that I could try and see if the plugs run cleaner on the drivers side.

I think I'm going to first try a bottle of royal purple fuel system cleaner to get rid of any carbon I've built up.

 

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Sea Foam may help on the carb cleaning.

Looking at the intake, its the pass side of the intake that I call , furtherest away from the head intake port, which kills my thought of the driver side clys are the dirtest?
The driver side intake is the lower floor, with feed the pass side cly, 2 4 6 8 , those are further away from the head intake so, I was thinking a larger jet for the furtherest away as most fuel tends to hang on the floor . I guess this kills my theory. Maybe I am thinking in reverse , as well as the rest of my body.

I understand the low tension ring, if it wont seat, I have used Marvel oil and a teaspoon of Bon Ami, back car out of garage and gradually pour down carb with motor running fast until all is gone and smoke is cleared, may notify fire dept that all is ok.

Is that an eproxied valve cover I see on the driver side? I have the same but on the pass side. Got so bad I took it off and hung it on the wall.
 

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When you get tired of running around in circles, give me an email at

[email protected]

and, I will send you pictures and full instructions to set the 99619-1 adjustable Crane stop plate up correctly for the CRANE adjustable vacuum advance, it is the ONLY canister that will work down that low in vacuum. This plate is available separately for stock type GM vacuum advances, and comes with the Crane full advance kits.

"Adjustable" vacuum advances from other manufacturers DO NOT allow vacuum leveladjustment down to 4 in/hg levels, they stop around 7 to 8 in/hg of vacuum, like the B28 does in real life.

Neither the B28, nor the B26 (also widely used), WILL NOT work down to that vacuum level, but, the Crane will, down to 4 in/hg vacuum.

With 16 initial, you would want to use 8 degrees MORE timing, 4th serration on the Crane stop plate, from the "load compensator" (vacuum advance).

I am assuming you are intending to use FULL MANIFOLD VACUUM sourcing for the unit, as using ported vacuum is both a waste of time and not the way to do it right.
 

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Dave, send the pics to me and I'll host them and post them. That way they'll benefit everyone. Click my user name for my email. Thanks.

Also, do you have a vac chart for the Crane can? They don't put one in their directions. I put a link to the Crane stop plate above.
 

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Discussion Starter #15
Is that an eproxied valve cover I see on the driver side? I have the same but on the pass side. Got so bad I took it off and hung it on the wall.
Welded valve cover. I have new ones but the gasket edges are not as high as the factory, plus I had to shorten the oil drippers cause my short lock nuts were rubbing.
 

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Welded valve cover. I have new ones but the gasket edges are not as high as the factory, plus I had to shorten the oil drippers cause my short lock nuts were rubbing.
Same here on the replacement. I used JB weld some 30 years ago, different shade of gray, then one day, a crack appeared.
 

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Discussion Starter #17
Well I added a can of Royal Purple fuel system cleaner and went on the highway for a long run doing 3500 rpm. Had to cut grass at my Mom's house so I took all the plugs out there before doing the grass and took pics of the plugs for reference. All 8 plugs are looking the way they should be, light tan to grey with today's crappy fuel. Got rid of all the carbon on the plugs from before on 1-3-5-7.

 

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What I have done is to shorten the slot in the vacuum arm by placing a penny between the lever and the arm and hit it with the buzz box and then remove the penny and file or use a dremel tool. I have found they give you 16 degrees, so I want only 10 and shorten it about 40%.

I run 18 initial, 20 mechanical for 38 total plus the 10 at lean cruise for a total of 48 all in cruising down the road, hammer it and the vacuum is gone. I believe the limit is 52 all in. The best thing you can do to learn about vacuum advance is to hook up a temporary gauge you can watch while driving around town.this will also tell you more about what power valve you should have in the carb. I just Finished up using the vacuum gauge and my lm1 meter tuning the stock 3310 for the psmcdr in Stanton. I have had the carb off 4 times this week and it is right there.

Timing and carburation go hand in hand, distributor first then carb idle circuit and lean cruise and finish with wot.then any issues like bogs or hesitation with squirters and pump cams.

The stock 3310 is enough for a 454!! I hope the 3310 is a dash 1 and has a rear metering block?
 

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What I have done is to shorten the slot in the vacuum arm by placing a penny between the lever and the arm and hit it with the buzz box and then remove the penny and file or use a dremel tool. I have found they give you 16 degrees, so I want only 10 and shorten it about 40%.

I run 18 initial, 20 mechanical for 38 total plus the 10 at lean cruise for a total of 48 all in cruising down the road, hammer it and the vacuum is gone. I believe the limit is 52 all in. The best thing you can do to learn about vacuum advance is to hook up a temporary gauge you can watch while driving around town.this will also tell you more about what power valve you should have in the carb. I just Finished up using the vacuum gauge and my lm1 meter tuning the stock 3310 for the psmcdr in Stanton. I have had the carb off 4 times this week and it is right there.

Timing and carburation go hand in hand, distributor first then carb idle circuit and lean cruise and finish with wot.then any issues like bogs or hesitation with squirters and pump cams.

The stock 3310 is enough for a 454!! I hope the 3310 is a dash 1 and has a rear metering block?
I thought all he had to do was put a stop bushing in the lower plate and be done no matter what the advance did.
I found COPO did an ingenious job of making his own stop.
I run the 3310-4 and it has the rear metering block.
 
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