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Old 10-15-2008, 04:55 PM
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Ok, many good advice, thank you all for your time, first i checked the play in the distributor and that was at minimum i believe, i guess it may not be to tight either, another thing i see you guys very often set your total timing at 34-36 degrees, in my experiments 38 has very often give me best results ? ! Maybe the cold here has something to do with it, at summer usually around 65 on Fahrenheit, and im going to try adding a switch on the ign.wire.
Thanks. Kristofer.

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Old 10-15-2008, 05:50 PM
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Originally Posted by Icelander
Ok, many good advice, thank you all for your time, first i checked the play in the distributor and that was at minimum i believe, i guess it may not be to tight either, another thing i see you guys very often set your total timing at 34-36 degrees, in my experiments 38 has very often give me best results ? ! Maybe the cold here has something to do with it, at summer usually around 65 on Fahrenheit, and im going to try adding a switch on the ign.wire.
Thanks. Kristofer.
Either your balancer /timing tab is inacurate (very likely) , your carb jetting is too rich or too lean and or you're getting a better et from that timing cause your motor wants more inital for better initial acceleration.
When everything is accurate and jetted right with the proper spark timing curve, you'll probabily find 34 to 36deg works better than 38deg.
Every small block I;ve had has run best with less than 38deg.
BBC's seem to like 38deg. Different motor.
The more inital the better the trhottle response and low end torque.
24deg at idle is not too much at all. More base initial allows a smoother more consistant advance curve that does not need to be quite so agressive. Peaks at around 3000 3200rpm. 34-36deg.

The only other possibility is the pump gas in Iceland has additives that are slowing down the combustion speed as compared to the fuel here.
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Old 10-15-2008, 06:52 PM
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Thanks f bird.
im going to lay down the total set up.
lets start on top
14" k&n air-cleaner 4" thick, holley 750 double pumper, edelbrock performer rpm air gap intake, world cyl.heads 200cc int.runners, 2,02 and 1.60 valves, 64cc chamber, comp magnum 280 cam,230degr.@050, 480 lift and 110 lobe seperation, installed using degree wheel "to be accurate" 1,5 ratio roller rocker arms, Je srp flat top pistons, 6"eagle i beam rods, eagle 5140 crank with 3,75 stroke, and this hei ignition, maybe i should switch to msd ? or get me this curve kit you mentioned, and should i connect the vacuum advance again ? it felt like she ran smoother with out it ?!
This engine is just recently assembled so there is allot of tuning and testing left, i jetted the carb with #73 front and 75 rear and used 6,5 hg power valve. You did mention earlier i should use 4.5hg valve ? ok
Then comes a th 400 trans with 3000rpm stall converter, 3;73 gear ratio and 26" tires, all this is now sitting in my 72 ss nova.
Thanks for your time and effort. Kristofer.
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Old 10-15-2008, 07:05 PM
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The secondary jetting is a bit lean for a 750DP. Usually wants 79 to 85 sec jet.
Most times a 80 jet is fine.

Yes the vacuum advance gets reconnected after all adjustments are done. A generic fixed non adjsutable vacuum advance canister has a 90% chance of not being right for your motor. Get a adjustable one and mess with it to find the best setup for your car. Usually around 10-12deg of vacuum advance at higway PT cruise. The rate (diaphram spring tension) in and out needs to be dialed in too.
Vacuum advance moves the magnetic pick up in the distributor to advance the timing. Sometimes the vacuum advance move the mag pic up too much and adversly affects the distributor rotor phasing with the distributor cap causing cross fire and missing. If you cannot solve this by limiting the vac advance travel to 10-12 deg the the rotor/magnetic pick up orientation needs to be adjusted so that the spark fires when the rotor tip is aligned with the post in the distributor cap. (adjustable rotor) or move the mag pick up on its plate.
This vac adv/rotor phasing issue shows up on a few but not all distributors.
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Old 10-15-2008, 07:12 PM
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Thanks again.
Kristofer.
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