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-   -   carb and timing questions (https://www.nopistons.com/1st-generation-specific-16/carb-timing-questions-58690/)

bigboi12A 04-17-2006 01:30 PM

Here we go ,, with out rambling on too mutch 2 months ago i had my motor bridge ported. love it but have a few issues. timing and carb tuning. I just bought a timing lite but i don't know what to set it to. second I have a 600cfm holley single feed. I let this guy in my car club mess with my **** and made it worse. he was ******* with the idle mixtures. Just by sound i toyed with it and have it real close. but the power isn't there above 8k ish. it use to be bad ass all they way to 10k. I believe that my carb is a 4150 holley. I'm assuming that clockwise is lean and counter clock wise is ritch. No I don't have an air/fuel gauge soon though. just want to know how many turns each screw should be,, thanks

j9fd3s 04-17-2006 02:21 PM

you want to set the timing after all the distributor advance is "in" if the timing is locked, you can set it at idle, if not you need to set it around 4000rpms.



what timing you end up at depends on the rest of the setup, start at about 20 BTDC Leading, 10 BTDC Trailing (not super critical). then you can fine tune it. you're gonna end up between 20-28btdc L



on the carb, the idle mixture screws only adjust the idle mixture, it has no effect on the top end. if you're missing top end, you might wanna look at the fuel filter/pump/pressure

BeaterRX7 04-17-2006 11:42 PM


Originally Posted by j9fd3s' post='814443' date='Apr 17 2006, 02:21 PM
start at about 20 BTDC Leading, 10 BTDC Trailing

It's recommended to keep an 8* split between leading and timing, but YMMV.

ArmyOfOne 04-18-2006 09:35 AM

Well on the carb I would start out with around 2 turns out form the seats. Yes clockwise lean, counterclockwise rich. Bridges like rich idle so prepare to waste gas like me.

bigboi12A 04-20-2006 05:11 PM

I set the L timing to 22 BTDC. what rpm should the trailing be set at. Last night when i was messs'in around I set the lite to 12, because there needs to be an 8 degree differance. at idle it didn't seem right and the higher I reved the car it appeared to advance more and more. < did that make sence, I hope it did . I'm new to ******* around with timing. Haven't touched the carb yet but I'm pretty sure it at least two turns.



Oh on a non related topic. Don't ever for any reason try to punch out those triangle pieces of glass. I had an eppisode on monday wigged out and wacked that little side window. Holly ******* ****, I'm a decent size guy and I put all my weight into that hit. It laughed at me and went thump!!. My hand hurts so bad.

BeaterRX7 04-20-2006 11:10 PM


Originally Posted by bigboi12A' post='814998' date='Apr 20 2006, 05:11 PM

I set the L timing to 22 BTDC. what rpm should the trailing be set at. Last night when i was messs'in around I set the lite to 12, because there needs to be an 8 degree differance. at idle it didn't seem right and the higher I reved the car it appeared to advance more and more. < did that make sence, I hope it did . I'm new to ******* around with timing. Haven't touched the carb yet but I'm pretty sure it at least two turns.

You need to set your timing with the engine revved to 3000 rpm. This makes sure all your advance is in and keeps you from knocking.

Oh on a non related topic. Don't ever for any reason try to punch out those triangle pieces of glass. I had an eppisode on monday wigged out and wacked that little side window. Holly ******* ****, I'm a decent size guy and I put all my weight into that hit. It laughed at me and went thump!!. My hand hurts so bad.
https://www.nopistons.com/forums/pub...1047683664.gif Doesn't common sense tell you not to do stuff like that?

j9fd3s 04-20-2006 11:34 PM


Originally Posted by bigboi12A' post='814998' date='Apr 20 2006, 03:11 PM

I set the L timing to 22 BTDC. what rpm should the trailing be set at. Last night when i was messs'in around I set the lite to 12, because there needs to be an 8 degree differance. at idle it didn't seem right and the higher I reved the car it appeared to advance more and more. < did that make sence, I hope it did . I'm new to ******* around with timing. Haven't touched the carb yet but I'm pretty sure it at least two turns.





you need to set the split at the same place you set the leading, with the vacuum advances disconnected.



the vacuum advances are different, so the split changes, but you want 8degrees at wot, so you need to set it with the vacuum and over 3k


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