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rocklefty19
05-30-2010, 07:13 PM
a 377 that starts fine revs up on the trailer but on the track has absolutly no power. brand new msd system and new carb still same problem. any suggestions????

CC28
05-30-2010, 09:03 PM
Oh, could be about 100 things. I chased the whole electrical system and it ended up being a blown head gasket. Check all grounds, fuel system, especially the pickup in the fuel cell, if its sucking shut you got no juice.

timmy20t1
05-30-2010, 10:03 PM
save u alot of problem do a compression check and go from there if u got a bad cylinder maybe run a leakdown test or pull the head and check the valves

papagorg
05-30-2010, 10:46 PM
check your valve lash,sounds like they may be too tight.

rocklefty19
05-31-2010, 04:34 AM
everything inside engine is fresh it doesnt have 10 laps on it.

dynoman14
05-31-2010, 09:28 AM
When you installed your new MSD box did your timing change???

You need to rotate your engine around to 35* BTDC or wherever you have your timing set. Pull the cap off the distributor and the trailing edge of the timing reluctor / small aluminum tab, should be in the middle of the distributors' magnetic pick-up.

If you are running regular advance you need to pull the advance forward by hand to verify.

This is a common problem and if you are right there then you have more work to do.

Chuckster421
05-31-2010, 09:52 AM
If your coil is in the cap, dont forget the yellow wire verses the white wire coil. The yellow wire is for chevy, the white wire is everything else GM. It will still idle fine, but under load it will misfire like crazy.

LM14
05-31-2010, 01:09 PM
We just went through this. Chased a motor for 2 weeks that wouldn't turn over 6400. Changed the MSD box, coil, fuel filter, timing, lash, carb, unplugged that tach. No change.

Put a new battery in and turned 7800. Get your battery load tested.

SPark

rocklefty19
05-31-2010, 05:49 PM
timing is set and the msd system is a pro builit system and i installed it just like i did on my car. the engine is question is my brothers. after the new ignition system and new carb the same symptoms were present. no power, and over heated.

Grace Slick
05-31-2010, 06:13 PM
Check your timing AND!!!! verify that your timing marks are correct.

DK1
05-31-2010, 06:37 PM
We just went through this. Chased a motor for 2 weeks that wouldn't turn over 6400. Changed the MSD box, coil, fuel filter, timing, lash, carb, unplugged that tach. No change.

Put a new battery in and turned 7800. Get your battery load tested.

SPark

What specs should the battery be at when load testing it? Or is it just pass/fail like a normal car battery?

LM14
05-31-2010, 10:47 PM
We had a sponsor that checked ours out. The cranking amps were about 250 lower than spec but it also wento into the "replace" section of the tester. Don't know the actual numbers, sorry. Ours was a red top mat glass style battery.

SPark

lucknoluck
06-01-2010, 08:28 AM
a 377 that starts fine revs up on the trailer but on the track has absolutly no power. brand new msd system and new carb still same problem. any suggestions????

Unless you are absolutely sure the cam was installed correctly I think cam timing is something to look at. Itís easy to make a mistake if it was not degreed in. One problem commonly made is replacing the timing chain and cam gear but not replacing the crank gear. They are a set for a reason. With a total advance of 36 or 38 degrees it should run like a rapped ape.

hpontap
06-03-2010, 07:19 AM
timing is set and the msd system is a pro builit system and i installed it just like i did on my car. the engine is question is my brothers. after the new ignition system and new carb the same symptoms were present. no power, and over heated.

Sounds like maybe the balancer outer ring has slipped and the timing is off to me.Is this a stock type balncer on the engine? If so, replace it with a new balancer and re-set timing to 36* and it should be fine.That would explain the loss of power and the over heating as well.

racer69
06-04-2010, 06:41 PM
I am like a lot of these guys...most likely its along the lines of cam or ignition timing. We had a problem with a new motor a couple weeks ago(not one of mine!) it qualified 4th but when the green dropped they drove by us. I told the owner it was something in the valves but idling in the pits it sounded great again. Come to find out, it had two broken rocker studs and one broken push rod! All on separate cyls! The stud girdle held everything in place but left enough to cause the bad run.

brs11
06-04-2010, 06:43 PM
Did someone in middletown ohio build it???

Check your timing, also I heard that if you have an older distrubitor and put a new msd box the wires are backward, never seen it but I just heard that.