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-   -   Engine loses power after launch (https://www.racingjunk.com/forums/showthread.php?t=32671)

lodilobo 10-02-2012 04:14 AM

The carb is a Demon 1090 Dominator, and yes it has a primary power valve (6.5) and secondary (plugged) according to the specs. I pulled up on the Demon site. I know less than nothing about power valves.

oldandtired 10-02-2012 11:42 AM

What is your vacuum at idle?

wrightway 10-02-2012 02:13 PM


Originally Posted by oldandtired
What is your vacuum at idle?

In gear.

oldandtired 10-03-2012 11:05 AM


Originally Posted by wrightway

Originally Posted by oldandtired
What is your vacuum at idle?

In gear.

Joe - if you're thinking what I'm thinking, the PV is cracking open.

wrightway 10-03-2012 04:24 PM

A 6.5 power valve sounds high to me for a 700 hp NA small block. but That should cause a rich low speed problem not what he has described.
Vent tube spill over and rear power valve installed in a hard leaving car sound like probable cause for symptoms described but sounds like he has the covered.

lodilobo 10-04-2012 03:34 AM

I haven't had the chance to get an accurate vacuum measurement yet....just too busy at work. I hope to do it today. I have a feeling the power valve is the culprit, based on some of the input here. Thanks.

kevinmooreo1 12-13-2012 10:05 AM

reply
 
Check your coil for a crack. I had the same problem during launch.

johnracer 12-29-2012 07:22 AM

Not trying to be a prick, but are you absolutely sure (you've checked) that the jet extensions are in the rear, not the front? Been there, done that.....also check to see if you have a starter cable or other wire that might contact the header during launch. Haven't done that, but I've seen it....

Johnny

lg406 07-08-2013 06:03 AM

Try replacing parts in the ignition system. Could be a loose wire.

markdunlap 07-08-2013 04:33 PM

Engine loses
 
Had a friend who fought this type of deal.

Ended up being a lose wire in the steering column that was shutting off power to the MSD box for a second.


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