Crab - Running - Vacuum problem sloved!!
Thread Starter
Racer
Joined: Sep 2003
Posts: 261
Likes: 0
From: Hershey Pa
Crab - Running - Vacuum problem sloved!!
Thanks to all you guys and your valuable help with this mystery.
As stated in my previous post the culprit was the power brake booster causing a huge vacuum leak. I plugged that port and changed plugs and off it went.
I opened up the secondary butterflies about 3/16 inch and I can easily set the idle. It idles nice and lopey at 900rpm. I took a vacuum reading and have about 5 inches of vacuum.
I picked up a new 2.5 power valve to install then I'll tune and set the timing. I'll keep the vac port plugged off and install a vacuum pump and reserve tank to run my accessories.
I also bought some 78 and 80 jets to try, I believe stock on the
4777-4 Holley 650 is 76?
Any thoughts on jet size for this application?
350 .060 over, .200 domed forged pistons, Air Gap intake, Eagle heads 230cc comb chambers, 2.08 int 1.6 exh. 10:1 compression, 519/523 lift @ 297/306 duration.
Thanks again everybody.
JZ
As stated in my previous post the culprit was the power brake booster causing a huge vacuum leak. I plugged that port and changed plugs and off it went.
I opened up the secondary butterflies about 3/16 inch and I can easily set the idle. It idles nice and lopey at 900rpm. I took a vacuum reading and have about 5 inches of vacuum.
I picked up a new 2.5 power valve to install then I'll tune and set the timing. I'll keep the vac port plugged off and install a vacuum pump and reserve tank to run my accessories.
I also bought some 78 and 80 jets to try, I believe stock on the
4777-4 Holley 650 is 76?
Any thoughts on jet size for this application?
350 .060 over, .200 domed forged pistons, Air Gap intake, Eagle heads 230cc comb chambers, 2.08 int 1.6 exh. 10:1 compression, 519/523 lift @ 297/306 duration.
Thanks again everybody.
JZ
Thread Starter
Racer
Joined: Sep 2003
Posts: 261
Likes: 0
From: Hershey Pa
Ah - yeah and "slove" in the title too. Brain is going faster than my fingers today. Pays to proof read.
But the crab runs great thumps and pounds at idle and screams when you hit the gas. Little bit of fine tuning yet. Can't wait to get it out on the road.
JZ
But the crab runs great thumps and pounds at idle and screams when you hit the gas. Little bit of fine tuning yet. Can't wait to get it out on the road.
JZ
Team Owner
Joined: Feb 2002
Posts: 29,702
Likes: 0
From: Sometimes I wonder... why is that frisbee getting bigger? Then it hits me.
Cruise-In X Veteran
St. Jude Donor '06
Originally Posted by Corz
thats one hell of a CRAB 
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