Cannot stay running in gear

Hello all...I recently completed a 2.8-3.4 swap in an S-10, and I am having problems with the motor stalling when I put it into gear.
Here are the parts:
3.4L (from donor camaro, overhauled w/new rings & bearings, block tanked/honed.) w/stock heads & valves; 1.52 roller rockers Comp Cams High Energy 260H camshaft; 260 duration/440 lift. Timing chain/gears to match. Holley 0-8007 390CFM 4160 carb (Throttle plates drilled with 1/16 holes) Edelbrock TorkerII tunnel intake Stock HEI dist w/MSD 6AL box; overhauled & w/new ignition module Holley "Red" electric fuel pump w/regulator set to 5.5PSI Mated to a stock 700R4 tranny.
I am pulling 19.5in of vacuum @1500 rpm, rock solid. All vaccum lines were replaced with swap, and have gone over every line w/carb spray looking for leaks. Nada.
Compression is great.
Ignition system functions perfectly.
I cannot get it to idle reliably lower than about 1200-1300 RPM; I expect this is a result of the cam. It is happiest above 1400. It runs very nicely through the rest of the RPM ranges, although it does seem to be slightly happier without the vacuum advance being hooked up, while the choke is on. Nothing major, just a very slight burbling. Mixture screws are 2 turns out.
I have drilled 1/16" holes in the throttle plates, it got quite a bit happier after I did that. I've tried cracking the secondaries a bit, and while it will idle a bit faster, it doesn't seem to make it any better. Still stalls when put into gear.
Any ideas what is going on here? I've run out, and getting very frustrated.
Thanks!
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crankup your fuel pressure to 7 p.s.i. and when you installed the cam what did you degree it to?
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Best I can get out of my regulator is 6PSI, and even though Holley claims that the "Red" only puts out 7PSI, it overwhelms a brand new set of needles rated for 12PSI if I don't use a regulator. (Actually 2 sets...)
As for the cam, it was done to 106 CL.
I know I am not going to be able to get a smooth idle out of this cam, but I think I can expect to idle somewhat.. I am going to try TDC'ing the engine again tonight and starting fresh. (again.)

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Is the cam ground on 106 or instaleed on 106?
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It was ground 110, installed 106.
wrote:

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Do the idle mixture screws make any difference in idle? Is the idle speed screw screwed in very far, like almost bottomed out? Does fuel dribble out of the boosters?
wrote:

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Mixture screws do make a difference, and are currently set to 1 1/4 turns out. Idle speed screw is actually only turned in slightly. I reached the point last night where I couldn't get it to idle any slower by adjusting the screws. Going to try backing off a half turn on the adjustment screw for the secondaries. No fuel dribbling out of the boosters either.
wrote:

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Ok, that idea is blown. Maybe a vacuum leak?

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Nope, I'd give anything for it to be that, at least I'd have something to aim at. I've done all the tests...carb cleaner everywhere, nada. Propane through a tube everywhere, nada. Hand over the carb...it dies. Vacuum gauge is rock solid @ 19inHg
Here is where I am at now. If I spray any ether into the carb (not a lot, just a misting above the choke tower) it falters and dies.
It's acting to me like the timing is too far advanced, but when I retard it, it dies. I am unable to get it to go lower than about 1300 now without dying. (Worse than before, need to backtrack.)
wrote:

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WOW! You got me! Time for a genius! Sorry....

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. . (top post) . What did you use for a convertor in the tranny? What stall speed?
Have you tried dropping it in gear at about 3000 rpm?
Is it a lock-up convertor? if so....how did you wire in lock-up? (ignition switch??)
and... have you tried disconnecting elect. feed to the tranny connector?
.... Suggestion?
I would set the engine up in that area that you stated it ran best at, above that 1400 rpm idle that you stated. Then be sure that you still have that good throttle response you said you had throughout the rest of the rpm ranges.
Then.....crank it Neutral...rev it up to 4000.. and drop it in LOW gear and take off.
the goal???? make sure the engine set-up is sound.
...... Common Sense Reasoning???
"I F" it idles well above 1400 rpms (which you stated) AND "I F" it runs well in all the other rpm ranges (which you also stated)
THEN...... your engine system is ready for a test drive and engaging the tranny is bringing the rpms down so low that the engine can't complete the combustion process effectively. (that area below 1200 rpms that you stated)
after thought..... my definition of running "very nicely through the rest of the rpm ranges" includes good throttle response.
. MarshMonster ~:~ ======== Cannot stay running in gear
snipped-for-privacy@telus.net (BlazerMaro)
Hello all...I recently completed a 2.8-3.4 swap in an S-10, and I am having problems with the motor stalling when I put it into gear.
Here are the parts: 3.4L (from donor camaro, overhauled w/new rings & bearings, block tanked/honed.) w/stock heads & valves; 1.52 roller rockers Comp Cams High Energy 260H camshaft; 260 duration/440 lift. Timing chain/gears to match. Holley 0-8007 390CFM 4160 carb (Throttle plates drilled with 1/16 holes) Edelbrock TorkerII tunnel intake Stock HEI dist w/MSD 6AL box; overhauled & w/new ignition module Holley "Red" electric fuel pump w/regulator set to 5.5PSI Mated to a stock 700R4 tranny.
I am pulling 19.5in of vacuum @1500 rpm, rock solid. All vaccum lines were replaced with swap, and have gone over every line w/carb spray looking for leaks. Nada.
Compression is great.
Ignition system functions perfectly.
I cannot get it to idle reliably lower than about 1200-1300 RPM; I expect this is a result of the cam. It is happiest above 1400.
It runs very nicely through the rest of the RPM ranges, although it does seem to be slightly happier without the vacuum advance being hooked up, while the choke is on.
Nothing major, just a very slight burbling. Mixture screws are 2 turns out.
I have drilled 1/16" holes in the throttle plates, it got quite a bit happier after I did that. I've tried cracking the secondaries a bit, and while it will idle a bit faster, it doesn't seem to make it any better.
Still stalls when put into gear.
Any ideas what is going on here? I've run out, and getting very frustrated.
Thanks!
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Sorry I haven't replied yet, had to do a HD recovery. =(
No, I don't have a lockup converter (other than the factory overdrive system.)
If I have it at around 1800 and shift into gear, it stays running at 1500 RPM, so that at least seems to be more of a normal RPM drop. (if I give it a bit of gas to get moving, I'm on a very slight incline and backing up) I've put about 40-50 miles on it since thenr. One theory from a guy I work with (used to wrench on the local stock circuit 15-20 years ago) is that it is simply too tight still, since the rings are not seated yet. I did another compression check, and it seems to bear him out. (13.4:1 instead of 9.5:1) I upped the octane in the tank from 87 to 94, and it does seem to be happier with that. Unfortunately it is a bear to keep running in gear when it's hot. If I let it go below 1500 at all, instantly dies, and I have to wait for it to cool down to restart. I'm going to put some more miles on it this weekend and then do another compression check. He tells me that once I get a couple of hundred miles on there, it should pretty much solve itself. Sound reasonable to you?
Incidentally, the throttle response is great through all the RPM ranges.
On Sat, 21 Aug 2004 23:35:11 -0500, snipped-for-privacy@webtv.net (Marsh Monster) wrote:

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13.4:1 on 94? How did you arrive at that from a compression test? What's the cranking compression?
rpm, rock solid. All vaccum lines

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Using the compression calculator that I found on a rod site. Give it the cranking compression and the current barometric pressure, and it spits out the ratio. A bit higher than what I worked out on paper (12.24:1, assuming 14.7psi atmospheric). In any case, the compression ratio is quite a bit higher than it should be atm. Cranking compression is 180 psi.
wrote:

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So you didn't actually CC anything? If that's the case you really have no idea where you are on compression. Also cranking compression is influenced by whether the cam is advanced or retarded, 180 cranking is a good number. No matter how you "figure" compression if you don't CC the dome and heads and know the EXACT gasket volume, it's just a guess. Don't get me wrong as being a smart ass, but 12:1 on 94pump gas is a "kiss of death" especially with iron heads....

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