Moparts

timing for a mild 360

Posted By: 71valiant

timing for a mild 360 - 10/09/09 09:36 PM


360 stock pistons
headers
airgap- carter 625 afb
I was running it at 35 but it was hard to start after it got hot. I set it back down to 30 and it starts alot better hot.

Where do yall run your timing?
Posted By: MoparforLife

Re: timing for a mild 360 - 10/09/09 10:37 PM

I run 34 on the street 360 and it is fine. They are all going to be different. Mine has a Crower 267/271 cam in it with stock pistons and headers. Try it at 33 and see what happens.
Is your distributor recurved so that the mechanical advance is fully advanced at the desired RPM. If not if your are measureing 35 degrees at say 25 hundred you will have too much initial becaue the advance is not fully extended and still advancing at a much higher RPM.
Posted By: RapidRobert

Re: timing for a mild 360 - 10/09/09 11:21 PM

35 total is making your initial too much & causing the labored cranking. I'd shorten the slots so you can start at ~10BTDC (depending on your cam) & still maintain 35 total(vac adv disconnected/plugged).
Posted By: MoparforLife

Re: timing for a mild 360 *DELETED* - 10/09/09 11:33 PM

Post deleted by MoparforLife
Posted By: 71valiant

Re: timing for a mild 360 - 10/09/09 11:35 PM

Quote:

I agree with the too much initial but for the reason I stated above. I have set a lot stock and higher compression engines at 35 total with 15 initial and not had a problem with hard warm starting. I haven't heard yet if the distribor is a recurve MP model or a stock distributor. If stock and testing for total at a low RPM will/may give a lot more initial thaan 15.




This is stock electronic. I tested it at idle.
Posted By: Anonymous

Re: timing for a mild 360 - 10/09/09 11:39 PM

Quote:


360 stock pistons
headers
airgap- carter 625 afb
I was running it at 35 but it was hard to start after it got hot. I set it back down to 30 and it starts alot better hot.

Where do yall run your timing?


so like 7.5-8.0:1 cr in that 360? run as much initial
as you can and limit the amount of mech. advance. mabey try 15-17deg initial and 20deg mech. should get you
where you need to be. that hot start prob could be many things not
related to timing.
Posted By: 71valiant

Re: timing for a mild 360 - 10/09/09 11:47 PM

Quote:

Quote:


360 stock pistons
headers
airgap- carter 625 afb
I was running it at 35 but it was hard to start after it got hot. I set it back down to 30 and it starts alot better hot.

Where do yall run your timing?


so like 7.5-8.0:1 cr in that 360? run as much initial
as you can and limit the amount of mech. advance. mabey try 15-17deg initial and 20deg mech. should get you
where you need to be. that hot start prob could be many things not
related to timing.



Forgot to add it has a 480/480 lift 292/292 duration 230@.050 cam. I put a mopar thin head gasket. I must have atleast 8:1 CR
Posted By: Anonymous

Re: timing for a mild 360 - 10/10/09 12:00 AM

Quote:

Quote:

Quote:


360 stock pistons
headers
airgap- carter 625 afb
I was running it at 35 but it was hard to start after it got hot. I set it back down to 30 and it starts alot better hot.

Where do yall run your timing?


so like 7.5-8.0:1 cr in that 360? run as much initial
as you can and limit the amount of mech. advance. mabey try 15-17deg initial and 20deg mech. should get you
where you need to be. that hot start prob could be many things not
related to timing.



Forgot to add it has a 480/480 lift 292/292 duration [Email]230@.050[/Email] cam. I put a mopar thin head gasket. I must have atleast 8:1 CR


that cam will bleed off ALOT of dynamic cr. good luck with that. TIMING is NOT gonna fix it.
Posted By: MoparforLife

Re: timing for a mild 360 - 10/10/09 12:08 AM

We have no idea what the initial is unless I missed something, we also don't know at what RPM he is setting the total at or if the advance has had the sprngs modified to bring the total in earier than a stock distributor.
If it hasn't the initial may be too much in order to get the 35 total at a low RPM. Stock advance will be know where near fully advanced at a lower RPM so alot of initial will be need to make up the difference + it will still be advancing well past that mark.
Posted By: forphorty

Re: timing for a mild 360 - 10/10/09 12:10 AM

Quote:

Quote:

I agree with the too much initial but for the reason I stated above. I have set a lot stock and higher compression engines at 35 total with 15 initial and not had a problem with hard warm starting. I haven't heard yet if the distribor is a recurve MP model or a stock distributor. If stock and testing for total at a low RPM will/may give a lot more initial thaan 15.




This is stock electronic. I tested it at idle.

You had 35 degrees at idle? If so, and you have a stock distributor, you probably have 50+ total. Too much.
Posted By: MoparforLife

Re: timing for a mild 360 - 10/10/09 12:31 AM

Quote:

Quote:

Quote:

I agree with the too much initial but for the reason I stated above. I have set a lot stock and higher compression engines at 35 total with 15 initial and not had a problem with hard warm starting. I haven't heard yet if the distribor is a recurve MP model or a stock distributor. If stock and testing for total at a low RPM will/may give a lot more initial thaan 15.




This is stock electronic. I tested it at idle.

You had 35 degrees at idle? If so, and you have a stock distributor, you probably have 50+ total. Too much.



Even if he checked the total of 35 degrees at 2500 it would still have way too much initial because it would still have a lot of advance to go, requiring the initial to be upped to make up for the advance that the mechanical advance has not been used yet.
To get a true total advance at a lower RPM the distributor mechanical advance must be recurved.
Posted By: stumpy

Re: timing for a mild 360 - 10/10/09 12:36 AM

Way too much timing at idle. You are checking it with the vacuum disconnected and plugged aren't you? I would think 15-18* at idle with 35* at 2500rpm.
Posted By: MoparforLife

Re: timing for a mild 360 - 10/10/09 12:52 AM

Quote:

Way too much timing at idle. You are checking it with the vacuum disconnected and plugged aren't you? I would think 15-18* at idle with 35* at 2500rpm.

Needs a recurved distributor to do it though or like I said above the initial will have to make up for the lack of the mechanical not being fully advanced.
Posted By: Anonymous

Re: timing for a mild 360 - 10/10/09 12:55 AM

timing isnt gonna help. he has waaaaay to much cam!
Posted By: 71valiant

Re: timing for a mild 360 - 10/10/09 01:14 AM

Quote:

timing isnt gonna help. he has waaaaay to much cam!



It runs good. Very streetable motor. I've run a 13.20@102 at the track.
Posted By: MoparforLife

Re: timing for a mild 360 - 10/10/09 01:18 AM

Quote:

Quote:

timing isnt gonna help. he has waaaaay to much cam!



It runs good. Very streetable motor. I've run a [Email]13.20@102[/Email] at the track.

I have seen a lot more cam than that run great in a low compression small or big block.
Posted By: 71valiant

Re: timing for a mild 360 - 10/10/09 01:20 AM

Quote:

timing isnt gonna help. he has waaaaay to much cam!



I think it really does need a recurved distributer.
Posted By: Anonymous

Re: timing for a mild 360 - 10/10/09 01:44 AM

well i bow down to you guys who run big cams and no compression. takes big kahunas to give up a second in ET (give or take a few tenths).
Posted By: MoparforLife

Re: timing for a mild 360 - 10/10/09 02:25 AM

Quote:

well i bow down to you guys who run big cams and no compression. takes big kahunas to give up a second in ET (give or take a few tenths).

That's not a very big cam. IMO It's got some duration but not a whole bunch of lift.
I was running low 12.0's with 485/495 & 284 duration with stock pistoned, cast unported 1.88 valve heads, LD4B intake and 750 Holley. Went to KB107 pistons, LD340 with Chuck Nuytenn prepped 750 and consistant low 11.70's. Not a second by a long shot.
Added Hughes stage 1 heads and cam 11.75 true calculated compression, shed a bunch of weight and still haven't gained said second.
Posted By: Anonymous

Re: timing for a mild 360 - 10/10/09 02:37 AM

Quote:

Quote:

well i bow down to you guys who run big cams and no compression. takes big kahunas to give up a second in ET (give or take a few tenths).

That's not a very big cam. IMO It's got some duration but not a whole bunch of lift.
I was running low 12.0's with 485/495 & 284 duration with stock pistoned, cast unported 1.88 valve heads, LD4B intake and 750 Holley. Went to KB107 pistons, LD340 with Chuck Nuytenn prepped 750 and consistant low 11.70's. Not a second by a long shot.
Added Hughes stage 1 heads and cam 11.75 true calculated compression, shed a bunch of weight and still haven't gained said second.


big enuff cam for the DYNAMIC cr. i also said give or take a few tenths.
my example: and 8:1 400 bbd went 14.20's. did nothing for the next
season except up the cr to 9.75 and went 13.0's. that was also
with a 230 cam. mpg's went up too. go figure.
but hey... each combo is different. but it all boils down to
the tuner. no need to chase your tail when you dont hafta.
Posted By: MoparforLife

Re: timing for a mild 360 - 10/10/09 05:56 AM

Good fo r you I am glad you got such a gain.
But the point we are after here is not performance but tough start warm. Up the compression here and it won't be a tough start warm, it just plain won't do it.
Get the the timing where it belongs and he will be be fine. He has already provent that backing it of help and that he already said he checkt totoal at TDC at 35, you should know that with out the distributor locked and retard or ignition kill switch to use while starting that that will not work. As for pwerformance, I wouldn't doubt seeing less timing result in better ET's. I know of several that this has happened to. In fact I went from 35 to 32 and gained well over a tenth on the average.
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