fine tuning question

[ZR1BLAZER]

im not the best at carbs so any help will do. i got everything together. rockers set, carb not leaking any more, fixed cooling issues total timing set at 36 degrees (20 initial) i traded the mighty demon for $400 and a new holley 650 double pumper. i ran the blazer down the road and it doesnt pop out of the carb anymore and it doesnt spit and spudder under heavy accel. anymore either. when you hit the gas it pulls pretty hard and scoots. but still no power at off idel. still wont break traction i know its tuning so the question is what should i do to tune the carb? the carb is set up just like the mighty demon 650 jets are 71/79 with # 28 squirters and 30cc accel pumps. also i now have a holley street dominator intake( designed like the original Z28 intake) duel plain with a 2\" spacer(to clear water neck) i can go to a stock style water neck if you think the 2\" spacer may be the problem? if yall have any ideas please share them. thanks.

[ZR1BLAZER]

oh and another thing that might help. my plugs are gapped at .050 or should i go to .035? theres no book that tells you where to put the gap? i know newer cars with a v8 run at like .035 but i had a 76 malibu with a stock 350 and HEI and plug gap on that was .050 so i dont know? i do have an Accel 300+ digital ignition box with remote 45,000 volt coil and MSD mech advance dis. again thanks for any info.

[carkiller]

i always thought a spacer was no good on a spread bore manifold. if it wasnt for the waterneck, it would be pretty easy to try it without the spacer.... http://www.s10v8.com/images/smilies/icon_biggrin.gif

[Midwestchopshop]

i usually gap my plugs at 40, seems to work fine for me, i think 50 is too much to make that spark jump. i dont remember what your set up is with your motor, meaning cam and all

[carkiller]

also wanted to say im running a .045 gap on my plugs with a hei distributor and a mallory 7al box. had no problems yet

[ZR1BLAZER]

all forged small journal 327, world products sportsman II heads 200cc intake runners 64cc chambers 2.02/1.60 valves comp cams magnum 280H 230/230 duration .480/.480 lift thought i had 10.7 comp but did some reasearch and found that i have 9.7.1 comp pete jackson gear drive cam and gear drive all installed straight up. of course i just told you my carb intake and ignition. now i did go out and set the floats thats right now and i used a vac gauge to set the idel air screws i reached a max of 18\" of vac. i took it for a drive and it felt better but still wont smoke the tires but when i launch from a dead stop i did lay two faint tire marks all the way through 1st gear. so it is getting better. any ideas??

[grimpuppy]

One of the problems you have is a pretty healthy cam in a small displacement motor. In a 327 that cam is going to have trouble making the torque down low that you desire. Advancing the cam will get you a little more low end torque.. You said it was installed strait up. Did you degree it or are you saying strait up you line the dots up? Most cams are ground from the factory with at least a couple degrees of advance already. What gear are you running? Small displacement and big cam will need steep gears. I would also say .05 is a little much on the plugs. Try closing them up a bit.

[gdmclnh]

I agree with grimpuppy. Lots of cam, small displacement. Equals not so good bottom end. Too much plug gap. Play with initial timing and it might help bottom end. 200cc intake runners don\'t help either.

[ZR1BLAZER]

according to comp cams that is the biggest cam i can run in the 327 and still be streetable. i am pulling 18\" of vac. so that says something? i do have a 200-4r trans with 4.56 gears and just installed a 9.5\" 3000 stall converter. i can idel at 800rpm in drive but it is lumpy but thats what i wanted. i know it is a big cam but i wanted something that with a duel plain intake and 4.56 gears give me some fun on the bottom and lots of power on top. when i come back i will regap the plugs how about the spacer? would i pick up more power on the bottom with out it?

[grimpuppy]

with a 3000 stall AND 4.56 gears you shouldn\'t have any trouble smokin the tires. That motor should love them geara and stall. Most people put in big cam and don\'t touch the gears and convertor and wonder why they have trouble. But you have done it right and used the gearing and convertor you need to run to make it all work.

I don\'t think the spacer is costing you enough that you should have trouble. Maybe only losing 20 ft/lbs of torque?? 4.56\'s should be able to overcome that pretty easy. What kina of ignition you running? I would bring the plug gap back down. Also you may want to recheck the timing. Make absoultly sure you have the right tab and good mark on balancer. It sounds like a motor that doesn\'t have enough timing in it. Try advancing the timing and see what it does. Go 5 degrees at a time and see if it starts to wake up. Just keep an ear open for detonation as you go.

[ZR1BLAZER]

thanks i will try that.

? i do have an Accel 300+ digital ignition box with remote 45,000 volt coil and MSD mech advance dis. set @ 20 initial (35 total @ 3000rpm) i reved all the way to 4000 and it stayed just about the same spot. just moving 1-2 degrees.

[BrickTop]

actually, i lean toward carb problems. i think that the heads ARE a little big for that little motor, but you shouldn\'t have ANY problem boiling the tires off with that stall and 4:56 gears. you could try adjusting the lever arm for the accelerator pump to see if that helps the stumble off idle, or, change the acc. pump cam so that it either pushes fuel earlier, or spreads the fuel discharge out over a longer period of time, or, try changing the jets. i had a stumble in my carb on my suburban, and when i went to bigger jets, it went away. and the stumble was just on tip-in throttle, wouldn\'t have thought it was the jets, but changing to a bigger jet fixed the stumble. try those, and make sure that you have the highest number power valves in there that you can get. i think they make a 12.5, i know they make a 10.5. pulling that much vaccuum at idle, and having a mechanical secondaries carb, you\'ll want the power valves to open asap when you floor it-so you will have enough fuel to mix with all that air the engine will be pulling through the throttle blades. brick.

[ZR1BLAZER]

hey brick. just to let you know there is no stumble in the carb or motor at all. that used to be my problem and it turned out to be a 2200 stall converter. now it just wont cook the tires. but has some serious power. i was thinking last night before i mess with the timing and all i am going to take a quick look at my carb when someone presses down the accelerator. i dont think the carb is opening all the way? the pedel is kinda of stiff and seems to be a bit short. i know i cant get it to idel down as low as it should because the cable. i think when the pedal is depressed all the way down its not pulling the carb all the way open. i will let ya\'ll know. if thats not it i will play with the timing a bit more. thanks guys.

[ZR1BLAZER]

well as i suspected the sec. are\'nt opening all the way. they just barely come open. i have the holley accel and dentent bracket so i cant adjust the cable at all. what should i do? i do still have a 750 3310-2 can i use the sec metering block from the double pumper and put the 750 together with the front and rear blocks, jets, and power valves? please help i am soooooo close. money is tight right now to so buying all kinds of new stuf is impossible. thanks guys.

[DMONOTJR]

hey dayna, give me a call. maybe we could swap out the cable/ pedal assemble and the bracket off of my truck. my landlord won\'t let me keep my truck at my house, and the place that i have my truck at now, well the guy who had the land lost it to \" goverment expantion\", so now i don\'t have anywheres to keep it. so i\'m going to have to get rid of it, and later on i\'ll start another one. maybe a new body style/ stepside t/t 4.3 5spd!!! i\'ve been looking. just give me a ring. 985-758-7253