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slightly built 383 likes lots of timing?? #2202304 11/25/16 01:34 PM 11/25/16 01:34 PM
Joined: Jul 2011 Posts: 781 wine country 8 8urvette OP super stock
8urvette OP super stock 8 Joined: Jul 2011 Posts: 781 wine country	I was helping my pops out yesterday with his 383. Pretty basic build- 383 .30 over 906 heads, bigger valves, cleaned up ports small tube headers edelbrock intake- 750 holley DP carb lumpy cam- i dont remember the specs but i had called comp and talked to them and they suggested this cam for this engine. 9.5 to one compression. once it is warmed up and idling at about 1100 if i hit the throttle it will backfire out the carb with the initial timing set at 12-15* if i change it to about 20* the idle drops a little and smooths out and does not have that hesitation but then i have mid 40's total at 2200+. what is that about? Is this okay?

Re: slightly built 383 likes lots of timing?? [Re: 8urvette] #2202307 11/25/16 01:39 PM 11/25/16 01:39 PM
Joined: Mar 2006 Posts: 9,848 MI, usa dvw master
dvw master Joined: Mar 2006 Posts: 9,848 MI, usa	Reduce the mechanical advance in the distributor. If it's an old style MP performance or factory you will have to weld the slots up. Newer style MP or after market usually have bushings or an adjustable plate. It may even like more than 20 initial. Just limit the total. Doug

Re: slightly built 383 likes lots of timing?? [Re: 8urvette] #2202310 11/25/16 01:41 PM 11/25/16 01:41 PM
Joined: Dec 2004 Posts: 10,555 Rittman Ohio fourgearsavoy I Live Here
fourgearsavoy I Live Here Joined: Dec 2004 Posts: 10,555 Rittman Ohio	I think 20 is fine but you might have to limit your total timing now but you wont know until you check it. Gus Treed by Doug Last edited by fourgearsavoy; 11/25/16 01:42 PM. 64 Plymouth Savoy 493 Indy EZ's by Nick at Compu-Flow 5-Speed Richmond faceplate Liberty box Dana 60

Re: slightly built 383 likes lots of timing?? [Re: 8urvette] #2202405 11/25/16 04:05 PM 11/25/16 04:05 PM
Joined: Aug 2003 Posts: 43,223 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,223 Bend,OR USA	Did you verify TDC on the balancer and timing tab when assembling it ? If not maybe you should Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: slightly built 383 likes lots of timing?? [Re: 8urvette] #2202433 11/25/16 04:49 PM 11/25/16 04:49 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	If its a stock balancer it could have slipped some giving you some bad numbers... or like Doug said.. curve the dist.. but with a bigger cam(lumpy) it will want more base timing but still want about 36* total

Re: slightly built 383 likes lots of timing?? [Re: MR_P_BODY] #2202571 11/25/16 08:57 PM 11/25/16 08:57 PM
Joined: Jan 2003 Posts: 1,376 Houston,Tx. L Lee446 pro stock
Lee446 pro stock L Joined: Jan 2003 Posts: 1,376 Houston,Tx.	I have found that 20* initial works well in lots of engines. If you have an older MP non adjustable dist, get hold of FBO. They make a great timing plate that is easy to install. It allows you to set up your dist for both initial and limits the total. The plate has slots in it that acts as a stop on the weight travel . It only costs $22 and when you order it, ask the owner how to set up your vacumn advance and you are set. I set up two distributors with them and they made a huge difference, being able to use the vac advance again really sharpened up the response and helped the mileage two. I highly recommend them.

Re: slightly built 383 likes lots of timing?? [Re: 8urvette] #2202573 11/25/16 09:04 PM 11/25/16 09:04 PM
Joined: Aug 2003 Posts: 43,223 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,223 Bend,OR USA	The reason I asked about the timing marks accuracy is most BB Mopars won't backfire through the carb. at idle when you open the throttle quickly in neutral unless the initial idle timing is close to TDC or even retarded past TDC I've also seen early model(pre 1966) balancers used on the 1966 and later motors with the later timing cover which ends up showing the TDC on that balancer to be about 15 degrees retarded on the later timing cover marks Murphy loves messin with hot rodders and racers Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: slightly built 383 likes lots of timing?? [Re: 8urvette] #2202595 11/25/16 09:43 PM 11/25/16 09:43 PM
Joined: Jul 2011 Posts: 781 wine country 8 8urvette OP super stock
8urvette OP super stock 8 Joined: Jul 2011 Posts: 781 wine country	Cab- I was wondering about the timing tab not being correct, I just laughed it off thinking, nah that cannot be the problem. The balancer is off a 67 383- maybe I should verify the TDC mark does line up. I seem to recall degreeing the cam, but it may have been in a different motor.... I don't know. The distributor is a MSD knock off I got at a car show new in box, and my father is using my MSD box which is known to be good. Maybe a new balancer and distributor is in order... Thanks for the ideas guys.

Re: slightly built 383 likes lots of timing?? [Re: 8urvette] #2202645 11/25/16 11:10 PM 11/25/16 11:10 PM
Joined: Nov 2003 Posts: 36,041 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,041 Lincoln Nebraska	As said I would suggest: confirming true TDC. set initial with "vac gauge method". Limit total to 38 with the FBO $22 plate (initial+slots with can plugged) to 38. play with springs. plug in/adj the can. consider degreeing the cam. see what your cranking compression is. Holler how things turn out live every 24 hour block of time like it's your last day on earth

Re: slightly built 383 likes lots of timing?? [Re: 8urvette] #2202749 11/26/16 02:55 AM 11/26/16 02:55 AM
Joined: Jun 2006 Posts: 5,163 CT GTX MATT master
GTX MATT master Joined: Jun 2006 Posts: 5,163 CT	Re-curve the distributor. Pop through the carb is usually lean, may need more accelerator pump shot. Now I need to pin those needles, got to feel that heat Hear my motor screamin while I'm tearin up the street

Re: slightly built 383 likes lots of timing?? [Re: 8urvette] #2204658 11/29/16 07:35 PM 11/29/16 07:35 PM
Joined: Feb 2007 Posts: 5,080 organ M maximum entropy master
maximum entropy master M Joined: Feb 2007 Posts: 5,080 organ	cab is right, those balancers slip all the time. also, 906 heads on a 383 makes about 3.5:1 compression ratio (maybe a little more, but you get the idea). stock stroke 383 takes work to end up with any real compression. that will be exacerbated by the cam reducing your dynamic c/r. Last edited by maximum entropy; 11/29/16 07:37 PM. for what is the good life if not doing things thoughtfully?

Re: slightly built 383 likes lots of timing?? [Re: 8urvette] #2204770 11/29/16 10:24 PM 11/29/16 10:24 PM
Joined: Nov 2004 Posts: 16,487 On the run… BloFish I Live Here
BloFish I Live Here Joined: Nov 2004 Posts: 16,487 On the run…	Maybe you should confirm tdc first. It really doesn't matter whether you win or lose… as long as you look good doing it! ‘65 A100 ‘69 ‘Cuda ‘73 Vega GT ‘06 Mega Cab ‘14 Mercedes SLK

Re: slightly built 383 likes lots of timing?? [Re: 8urvette] #2205152 11/30/16 11:53 AM 11/30/16 11:53 AM
Joined: Jan 2003 Posts: 24,562 Brookeville, Md Mr.Yuck Not enough dumb comments...yet
Mr.Yuck Not enough dumb comments...yet Joined: Jan 2003 Posts: 24,562 Brookeville, Md	Originally Posted By 8urvette I was helping my pops out yesterday with his 383. Pretty basic build- 383 .30 over 906 heads, bigger valves, cleaned up ports small tube headers edelbrock intake- 750 holley DP carb lumpy cam- i dont remember the specs but i had called comp and talked to them and they suggested this cam for this engine. 9.5 to one compression. once it is warmed up and idling at about 1100 if i hit the throttle it will backfire out the carb with the initial timing set at 12-15* if i change it to about 20* the idle drops a little and smooths out and does not have that hesitation but then i have mid 40's total at 2200+. what is that about? Is this okay? I had a .030 10:1 (or more) 383, w/ 509 cam, ported 915's (2.14/1.81), Torker II, 750DP and the usual stuff that loved timing. I had 42* in full at 2600rpm. A friend told me that was too high I should back it down to 38* and it slowed the car down. Another friend ran his 383 at 44*. [IMG]http://i66.tinypic.com/pui5j.jpg[/IMG] Coming soon!!!!

Re: slightly built 383 likes lots of timing?? [Re: Mr.Yuck] #2205169 11/30/16 12:28 PM 11/30/16 12:28 PM
Joined: Jan 2003 Posts: 75,043 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 75,043 U.S.S.A.	Originally Posted By Mr.Yuck Originally Posted By 8urvette I was helping my pops out yesterday with his 383. Pretty basic build- 383 .30 over 906 heads, bigger valves, cleaned up ports small tube headers edelbrock intake- 750 holley DP carb lumpy cam- i dont remember the specs but i had called comp and talked to them and they suggested this cam for this engine. 9.5 to one compression. once it is warmed up and idling at about 1100 if i hit the throttle it will backfire out the carb with the initial timing set at 12-15* if i change it to about 20* the idle drops a little and smooths out and does not have that hesitation but then i have mid 40's total at 2200+. what is that about? Is this okay? I had a .030 10:1 (or more) 383, w/ 509 cam, ported 915's (2.14/1.81), Torker II, 750DP and the usual stuff that loved timing. I had 42* in full at 2600rpm. A friend told me that was too high I should back it down to 38* and it slowed the car down. Another friend ran his 383 at 44. this is correct, 383's like timing , when I was at the pure stock drags one of the racers told me to bump the timing up to 42 , I chickened out and only went to 40* but the car did pick up some ... running up my post count some more .

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