Another timing question

[moparisbest]

Timing 41 ° total timing. 496 stroker bb .is this ok . Cars runs grate no vacuum advance hooked up. Was thinking of hooking up the advance for a better idle. Was thinking it would make it run cooler in traffic. Any input. Tuned on Dyno. ( not by me ) I'm kinda a layman when it comes to this stuff.

 

[famous bob]

Timing 41 ° total timing. 496 stroker bb .is this ok . Cars runs grate no vacuum advance hooked up. Was thinking of hooking up the advance for a better idle. Was thinking it would make it run cooler in traffic. Any input. Tuned on Dyno. ( not by me ) I'm kinda a layman when it comes to this stuff.

View attachment 1715313430

View attachment 1715313431

Mine is hooked up via the fuel inj. system, have it set at 50 max. ----,

 

[Mattax]

Was thinking it would make it run cooler in traffic.

Yes. & Highway cruising too.

Was thinking of hooking up the advance for a better idle.

Depends on the distributor and the engine. In general no. Use vacuum advance to compensate for the increased time for combustion with leaner, less dense mixtures in the cylinder. Strong idle calls for somewhat richer mixture than when cruising.

Timing 41 ° total timing. 496 stroker bb .is this ok . Cars runs grate no vacuum advance hooked up.

Depends on how quickly the advance comes in. Big difference if its 41* at 2800 rpm, than if its at 3800 rpm. I don't know how your set up may vary but the older Direct Connection guidelines will give you a reference point.
https://www.forabodiesonly.com/mopa...mopar_performance_instruction-png.1715175314/
Notice that's timing at 2600-2800 rpm. Max mechanical timing might be a bit higher if it does not occur until over 3000 rpm.

 

[AndyF]

41 degrees total is way too much for wide open throttle work. A BB Mopar typically doesn't want more than about 36 degrees although it does depend on the cylinder head that is on the engine. If you are driving on the street then you should have vacuum advance. With a performance cam you'll want about 45 degrees total when cruising down the freeway. 35 in the distributor and another 10 in the vacuum advance gets you there.

 

[moparisbest]

And now I got a different problem. When I hook up the timing light it Boggs down and dies. (Fitech efi )

 

[AndyF]

And now I got a different problem. When I hook up the timing light it Boggs down and dies. (Fitech efi )

That is kind of funny. Good luck with that!

 

[AndyF]

I will say that I was helping with a dyno session the other day and the first three timing lights we tried would not fire with the EFI system that the engine had. The engine builder happened to have 4 timing lights in the shop (all different brands). The fourth one worked which was a good thing since the dyno session would've been a bust if we couldn't set the timing. I've never known a guy to have 4 timing lights before (I only own 2 myself) but I'm glad he did since it saved our bacon.

I should add that we had to use a stand alone battery with the fourth timing light. That engine was touchy!

 

[AndyF]

And now I got a different problem. When I hook up the timing light it Boggs down and dies. (Fitech efi )

That reminds me of a dyno session a few weeks back where the engine would shut off when we turned on the electric water pump. This was an EFI engine. Evidently it didn't like the water pump. We eventually fixed it by running a separate wire from the battery to the water pump.

 

[famous bob]

41 degrees total is way too much for wide open throttle work. A BB Mopar typically doesn't want more than about 36 degrees although it does depend on the cylinder head that is on the engine. If you are driving on the street then you should have vacuum advance. With a performance cam you'll want about 45 degrees total when cruising down the freeway. 35 in the distributor and another 10 in the vacuum advance gets you there.

^^^^^^^^^^^
Interesting , I used to run 56 total w/ the vacuum advance on my hot 406 sbc, but that was out on the hiway cruising. Was recommended by an 18 time national record holder, matter of fact he set the dist. up for me. He has said that bigger engines liked more timing ???? That being said , I do not claim to know much about this stuff . Not arguing .

 

[moparisbest]

That reminds me of a dyno session a few weeks back where the engine would shut off when we turned on the electric water pump. This was an EFI engine. Evidently it didn't like the water pump. We eventually fixed it by running a separate wire from the battery to the water pump.

I'm going to try an extra battery to the side just for light see if it works it seems like the timing light is feeding back to the efi ?

 

[moparisbest]

^^^^^^^^^^^
Interesting , I used to run 56 total w/ the vacuum advance on my hot 406 sbc, but that was out on the hiway cruising. Was recommended by an 18 time national record holder, matter of fact he set the dist. up for me. He has said that bigger engines liked more timing ???? That being said , I do not claim to know much about this stuff . Not arguing .

I spoke with the engine builder and he said 41° is where it made its most power. And I could lower it to the 36 to 38 settings

 

[moparisbest]

I will say that I was helping with a dyno session the other day and the first three timing lights we tried would not fire with the EFI system that the engine had. The engine builder happened to have 4 timing lights in the shop (all different brands). The fourth one worked which was a good thing since the dyno session would've been a bust if we couldn't set the timing. I've never known a guy to have 4 timing lights before (I only own 2 myself) but I'm glad he did since it saved our bacon.

I should add that we had to use a stand alone battery with the fourth timing light. That engine was touchy!

got it brand new one of the fancy digital ones. Going to try external battery. If that doesn't work going to take it back and get the cheaper one and try it.

 

[512Stroker]

I spoke with the engine builder and he said 41° is where it made its most power. And I could lower it to the 36 to 38 settings

What kind of fuel are you planning to use? Pump fuel? Octane rating?

 

[moparisbest]

What kind of fuel are you planning to use? Pump fuel? Octane rating?

It's a street car on 91 pump gas .

 

[512Stroker]

It's a street car on 91 pump gas .

If I run my 10.5:1 iron head 340 at more than 32 degrees, all in, on pump 91 fuel it pings bad on acceleration.
I run a pro billet MSD distributor with out vacuum advance.

 

[moparisbest]

You guys are the bomb . Thanks for all the replies. I was able to hook timing light to external battery sorce and light worked. Tell me if this is right all in at 38° intial was showing 8° to 10° on the dot . Or do I look at where the line is for intial. If so it 1/4 inch below the timing marker . Sorry for the question I just never timed a engine. Back when I was young I would do it by ear and black Mark's on the road. When the hesitation was gone and the idle was smooth it would usually be spot on in performance department.

 

[moparisbest]

Ended up 14° btdc 38° 3000 rpm all in no vacuum.
Idle is perfect and has nice crisp acceleration 13.5 Afr. At idle.

 

[famous bob]

I spoke with the engine builder and he said 41° is where it made its most power. And I could lower it to the 36 to 38 settings

Out cruising on the hi way the timing is for gas mileage , not all out power/ that`s a diff animal.

 

[famous bob]

Ended up 14° btdc 38° 3000 rpm all in no vacuum.
Idle is perfect and has nice crisp acceleration 13.5 Afr. At idle.

20* initial 34 in at 3000, 50 total cruising on the hiway----------
AT 21 initial , seems like it doesn`t start so easy when hot. The darn thing seems to get better mileage than my stock 440 1969 coronet
that I used to have , altho I haven`t got around to actually checking it. !!
Raps like a sbc, with the fuel inj., and and a fairly loose convertor .
The stroker assembly was race balanced by hughs engines , on a motor plate, and is as smooth as a babies but , except for the exhaust noise.

 

[famous bob]

If I run my 10.5:1 iron head 340 at more than 32 degrees, all in, on pump 91 fuel it pings bad on acceleration.
I run a pro billet MSD distributor with out vacuum advance.

I think some of u guys are confusing cruising , with all out acceleration timing , which is set at 34 on mine , the 50 max is limiting at cruising not much load /gas mileage.---------- I think I said that right .
I know in my own mind what I mean -----------_LOL