Posted By: skep419
carb jet ? - 05/02/09 01:54 PM
Do the primary jets have anything to do with idle setting?
carb jet ?
Posted By: fox
Re: carb jet ? - 05/02/09 02:33 PM
No.
Are the boosters dripping?
Are the adjustment screws doing anything?
How open are the primary plates? You may need to open the secondaries if this is a holley.
Are the boosters dripping?
Are the adjustment screws doing anything?
How open are the primary plates? You may need to open the secondaries if this is a holley.
Posted By: skep419
Re: carb jet ? - 05/02/09 02:45 PM
it idles fine in the garage. take it out and dies while pulling up to stop signs. Had to drill the primaries. transfer slots are now in spec. smells rich kinda bogs to a hault but starts right up. if you feather the gas rolling up to it you can keep it running. 600 holley dp
timing is 13 base 32 full in at 2500
timing is 13 base 32 full in at 2500
Posted By: fox
Re: carb jet ? - 05/03/09 01:20 AM
What do the plugs look like? Are they black?
It gives me the thought that the primary jets are too big, it is running rich.
Give me the list number and I may be able to find the original jet size from a holley book.
Are you the original owner of this carb?
If it runs best with this size jet--at WOT, you may need to open the power valve channel restiction and reduce the jet size. Manytimes getting the jets a little lean really increases the throttle response. But you must pay attention to spark knock.
It gives me the thought that the primary jets are too big, it is running rich.
Give me the list number and I may be able to find the original jet size from a holley book.
Are you the original owner of this carb?
If it runs best with this size jet--at WOT, you may need to open the power valve channel restiction and reduce the jet size. Manytimes getting the jets a little lean really increases the throttle response. But you must pay attention to spark knock.
Posted By: skep419
Re: carb jet ? - 05/03/09 02:09 AM
Quote:
What do the plugs look like? Are they black?
It gives me the thought that the primary jets are too big, it is running rich.
Give me the list number and I may be able to find the original jet size from a holley book.
Are you the original owner of this carb?
If it runs best with this size jet--at WOT, you may need to open the power valve channel restiction and reduce the jet size. Manytimes getting the jets a little lean really increases the throttle response. But you must pay attention to spark knock.
360 9.37 comp h405p speed pro pistons, stock rods, new stock cast crank, mild port ede heads, mopar 273 ductile rockers, xe284 comp cam, ede air gap. 1" phenolic spacer 4 hole, 727 2800 stall, 8 3/4 3.91 suregrip. was running a 4150hp 750 mechanical but didn't have the throttle response. I switched to a 600 holley dp and had great throttle response but couldnt get it to idle.
I just switched back to the 750 to make sure it wasnt just my imagination and it idles sweet but bogs off idle?
I tried different jets in the 600 didnt make any difference. the primary's are drilled on both to get the transfer slots at a normal range.
On the hp I'm running 69 and 75 with a 4.5pv
68 and 74 seemed to be the best for the 600 wot plug color
oh the 750 I bought brand new the only thing that isn't stock is I tried messing with bigger squirters. it had 28 and 29 and i have 32's.
Posted By: skep419
Re: carb jet ? - 05/03/09 02:11 AM
0-82651 69 75 Primary - .029
Secondary - .028
here is the specs for the 4150 hp 750
Is this to big of carb for my combo?
Secondary - .028
here is the specs for the 4150 hp 750
Is this to big of carb for my combo?
Posted By: fox
Re: carb jet ? - 05/03/09 12:18 PM
Did you try a longer accelerator pump shot on the 750? I would say it is the better choice for your motor. Some just needd to learn to drive a mechanical secondary carb, but it can be tuned out. The 650, are you sure the metering block gaskets are ok? Did you try lowering the floats?
Posted By: skep419
Re: carb jet ? - 05/03/09 04:12 PM
tried lower the floats did nothing.
so i need a 50 accel pump
so i need a 50 accel pump
Posted By: skep419
Re: carb jet ? - 05/03/09 10:37 PM
When I blurp (quick snap) the carb makes a throaty noise. I'm going to reset the valves but any other ideas?
Posted By: fury4speed
Re: carb jet ? - 05/03/09 10:52 PM
What fuel pump pressure are you running? you could be blowing the needle and seat , just a thought.
Posted By: skep419
Re: carb jet ? - 05/04/09 04:27 AM
6.5
Posted By: GomangoCuda
Re: carb jet ? - 05/04/09 11:54 AM
Quote:
timing is 13 base 32 full in at 2500
Quote:
xe284 comp cam,
This is probably a timing issue. That cam is going to want at least 18 deg at idle. Try bumping it up 5 deg to 18 base and 37 total. If that helps then I would do some work on the advance curve to shorten it up a few degrees and come in full a little quicker. Actually a spring change would probably do both. I would be looking for 20 at idle and 35-36 total.
Posted By: fox
Re: carb jet ? - 05/04/09 01:26 PM
Late timing can be the cause.
To eliminate the carb, I'd try this.
Go out to a quiet parking lot and slam on the brakes to make it happen.
The imediately shut off the ignition, remove the air cleaner and look in the carb. Are the plates wet with fuel? If so it is fuel slosh.
To eliminate the carb, I'd try this.
Go out to a quiet parking lot and slam on the brakes to make it happen.
The imediately shut off the ignition, remove the air cleaner and look in the carb. Are the plates wet with fuel? If so it is fuel slosh.