Help?
#1
Junior Member
APPRENTICE
Thread Starter
Join Date: May 2007
Posts: 20
Help?
I just picked up an S-10 with the following engine combo, and it starts and runs but loads up if it sits for any time at all. Can I jet it down and take care of this? I would like to keep the carb thats on it, I believe it has the stock #73 jets on both ends...what would you recommend? Thanks
383 stroker with around 450hp...The block is a 010 4 bolt main. Internally balanced bored and honed with torc plates .30 over. Steel crank.CA rods all ARP bolts. Block was sonic checked. New style Vortec heads.hyd lifters. Comp cam custom ground 512 lift.comp valve springs. Double row timing chain. Melling high volume oil pump. True 10 3/4 comp almost 11.1.Speed pro hypereutectic pistons with coated skirts. Polished Aluminum fabricated valve covers. Milodon 7 qt oil pan. Elebrock aluminum water pump. Holley 4150 series 950hp.Polished aluminum intake Hurricane. Aluminum pulleys. Griffin radiator. Sanderson ceramic coated headers.
383 stroker with around 450hp...The block is a 010 4 bolt main. Internally balanced bored and honed with torc plates .30 over. Steel crank.CA rods all ARP bolts. Block was sonic checked. New style Vortec heads.hyd lifters. Comp cam custom ground 512 lift.comp valve springs. Double row timing chain. Melling high volume oil pump. True 10 3/4 comp almost 11.1.Speed pro hypereutectic pistons with coated skirts. Polished Aluminum fabricated valve covers. Milodon 7 qt oil pan. Elebrock aluminum water pump. Holley 4150 series 950hp.Polished aluminum intake Hurricane. Aluminum pulleys. Griffin radiator. Sanderson ceramic coated headers.
#5
Senior Member
RACING JUNKIE
Join Date: May 2006
Posts: 2,044
Yeah hate to say it but your carb is on the HUGE side for the engine you described. I'd say hang on to it though and build a high compression 406 with a big solid roller cam and it will love it.
On the other hand if you just have to use that carb, first thing I would do is check your float level its idling to rich and has nothing to do with your main jets A likely cause could be a high float level after checking or adjusting float level and still idles rich you'll need to adjust your idle mixture screws, run them all the way in till lightly seated and back out one half turns, thats usually a good starting point then go either back in or out to get a smooth idle, remembering not to make to big a adjustments while doing this, some carbs are real senstive in this area. Goodluck, Charles
On the other hand if you just have to use that carb, first thing I would do is check your float level its idling to rich and has nothing to do with your main jets A likely cause could be a high float level after checking or adjusting float level and still idles rich you'll need to adjust your idle mixture screws, run them all the way in till lightly seated and back out one half turns, thats usually a good starting point then go either back in or out to get a smooth idle, remembering not to make to big a adjustments while doing this, some carbs are real senstive in this area. Goodluck, Charles
#6
Cepx brought up a good point. I run a 950hp on my truck, and it is extremely sensitive to the idle mixture adjustment. The pesky things seem to back out about ten passes or so. I'm with the rest of the bunch though, I believe the carb is a tad large for the current set up.
#8
Senior Member
MASTER BUILDER
Join Date: Dec 2005
Location: Rutherfordton North Carolina
Posts: 192
If that carb hasn't been molested the stock jetting is 78 all the way around,with 73 jets someone probably has richened the idle mixture to cover up a lean stumble.put the stock jetting back in and reset the idle mixture and adjust from there. a large carb on a small engine needs more jet and smaller high speed air bleeds, you don't have the velocity to tip in the boosters soon enough to prevent a stumble without overly rich idle settings.Bill
#10
Senior Member
MASTER BUILDER
Join Date: Dec 2005
Location: Rutherfordton North Carolina
Posts: 192
Warm the engine up,shut it down,screw all 4 mixture screws in until they lightly seat.back all 4 out 1.5 turns,start the engine and turn all 4 in or out 1/4 turn at a time until you get the highest idle speed.you may need to slow the idle sped down as you do this if the screws were set way rich.after you find your highest idle sped richen the mixture 1/8 turn on each screw.this will put you in the ball park.Bill