Topic: Tuning 383 help!!!
in Forum: C3 Fuel, Emission Control, and Exhaust Systems
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Yelm, WA - USA
Joined: 7/12/2007
Posts: 356
Vette(s): 1979 L82 4 speed Scat 383 crank 190 cc Procomp Aluminum Heads 202 160 stainless valves GM Powder metal rods Speedpro H860CP Hypereutectic pistons 280 cam hydralic HEI Pro comp 1.6 roller rockers Mighty Demon 750 Sanderson CC1AP Hedders.
I'm not sure what I'm doing wrong but I can seem to get the timing right on my engine. I'm getting a lot of backfire and (detonation??) I'm setting it at around 16 advance idle turned all the way down no backfire seems to idle ok. Once I put a load on the engine it really backfires and misses. Seems like if I advance the timing more it dosen't help. Yeah I really have no idea what I'm doing so any help would be greatly appreciated.
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16 deg at idle???? That sounds a bit fat to me! Do you know what the total advance is, and what rpm it comes in at?
Ben is great at explaining how to get the correct timing/advance to get the best response. I'm no good at explaining stuff like that...
In the meantime, you may want to have a look at a couple of threads on the timing subject, and the best way to do it...
I hate timing lights...
Setting timing
Both of these threads are the best you'll find on the subject...I have them "bookmarked" for my own reference.
Adams' Apple 2008-01-24 20:39:19
Ben is great at explaining how to get the correct timing/advance to get the best response. I'm no good at explaining stuff like that...
In the meantime, you may want to have a look at a couple of threads on the timing subject, and the best way to do it...
I hate timing lights...
Setting timing
Both of these threads are the best you'll find on the subject...I have them "bookmarked" for my own reference.
Joel Adams
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Former Member
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Yelm, WA - USA
Joined: 7/12/2007
Posts: 356
Vette(s): 1979 L82 4 speed Scat 383 crank 190 cc Procomp Aluminum Heads 202 160 stainless valves GM Powder metal rods Speedpro H860CP Hypereutectic pistons 280 cam hydralic HEI Pro comp 1.6 roller rockers Mighty Demon 750 Sanderson CC1AP Hedders.
Ok I should have searched first those posts they answered almost all my questions. I was doing it back asswords and that would explain the firebalss coming from my carb today. Now I know what all those numbers on my damper are for
Thanks Joel!
Lifetime MemberKingston, PA - USA
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Good job, Joel
Alan
Former Member
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Yelm, WA - USA
Joined: 7/12/2007
Posts: 356
Vette(s): 1979 L82 4 speed Scat 383 crank 190 cc Procomp Aluminum Heads 202 160 stainless valves GM Powder metal rods Speedpro H860CP Hypereutectic pistons 280 cam hydralic HEI Pro comp 1.6 roller rockers Mighty Demon 750 Sanderson CC1AP Hedders.
Yeah I had it totally screwed up I was way too advanced, my headers started lighting up. Just as I was getting it dialed in, I ran out of gas! 
I'm going to get a vacuum gauge and check out what ben was talking about, that might work out good on my engine.
79rebuild 2008-01-26 19:00:44
I'm going to get a vacuum gauge and check out what ben was talking about, that might work out good on my engine.
Lot's of progress today, even though I still don't know what I'm doing. A couple things I learnt were, don't use the ported vacuum port on my engine and I was running way to lean, I finally got it to shut down without dieseling and no fireballs out of the carb when giving it gas. I'm going to get a vacuum gauge tomorrow and play with that. I set the timing with a light my 383 likes about 16 initial btdc run it up to 3k and I'm right at 36. Hooked up the advance and adjusted the fuel air and idle and it runs a lot better. Still a pop in the exhaust on the passenger side but hopefully tomorrow I can work it out with the vacuum gauge. Won't idle to well under 1000 so I'm not sure if that's just my stroker or me. Those two posts were awesome thanks again Joel!
in Forum: C3 Fuel, Emission Control, and Exhaust Systems
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