Max Timing for L69 with Bolt on Mods & Comp Cam

S

scoti

Master Mechanic
Sep 5, 2019
294
63
Texas
That cam is going to be a pig off idle, but should wake it up once the rpm's get over 3500.

Regarding the timing settings - no idea how to do it, but if you have 34-36 degrees of all in timing and it's not detonating/pinging, then it should be good.
a 218/224 @ .050 is going to be a 'pig' off idle? It seems big for a 305 but this one does have supporting hardware so I wouldn't think it would be that bad.
 
Supa.Slo.SS

Supa.Slo.SS

Not-quite-so-new-guy
Thread starter
Aug 7, 2020
20
3
CA
That cam is going to be a pig off idle, but should wake it up once the rpm's get over 3500.

Regarding the timing settings - no idea how to do it, but if you have 34-36 degrees of all in timing and it's not detonating/pinging, then it should be good.
For my own knowledge, what is it about the cam that makes it a pig? Anything i can do to make it better, like a different torque converter, bigger ratio rockers, stiffer springs?
 
64nailhead

64nailhead

Royal Smart Person
Dec 1, 2014
1,417
113
Upstate NY
For my own knowledge, what is it about the cam that makes it a pig? Anything i can do to make it better, like a different torque converter, bigger ratio rockers, stiffer springs?
Needs a converter to get up on it. A quality converter will seem like night and day.

Quick example - I put more cam than that in a 4.8 LS- I know , LS, but all of the same principles apply. With a new stock converter the car was unbearable to drive on the street until it hit 4K rpms. It has a turbo and it took 3 seconds of WOT to make any boost. Enter a Freakshow 3800 stall - 100% completely different car to drive. The car drives, without converter slip, at 1800-2500 without issue, but as soon as I drop the loud pedal,the rpms pickup immediately to 4000-4200. It ‘gets up on the converter’ in 1/2 a second. It’s the best of both worlds.It gets into the power band ‘on demand’ based on my right foot.

but you need to get your tune straight 1st. A converter is not a crutch to a crappy tune, and vice versa.

Your 305 will make an easy 275 with that cam and headers if you can only get there with a decent tune.

Good luck - Jim
 
Mac442

Mac442

Greasemonkey
Apr 25, 2020
122
43
Ocean County, NJ
Not sure what gears you have, but once you have your timing set the best way to really wake that 305 up is by changing to lower (numerically higher) gears in the rear. This was the way GM did it for the Chevy 305s and Olds 307 HO.
 
Clone TIE Pilot

Clone TIE Pilot

Royal Smart Person
Aug 14, 2011
2,311
113
Galaxy far far away
UPDATE:

So for those following with the same issues/question, a member from a different forum pointed out if you still have your OEM Emissions Sticker it actually gives you the procedure. If you don't have it, go to OPGI.com and search decal emissions for your car & you can see the procedure.

I realized my mistake, the plug(s) I was disconnecting and messing with were the wrong ones. I should have paid more attention but on the driver side of the distributor NONE of those wires that plug into the distributor on that side are 4 wires, they are 3 wire or less.

The wires/plug I needed to disconnect was more on the passenger side of the distributor. As many had said, its a 4 wire plug that comes out of the bottom portion of the distributor with a black plug (maybe 2.5" long) that that has all 4 pins in a straight row & that plugs into the wiring harness.

Below is the picture and the stated process.

Can't say I understand the verbiage entirely, so if someone can translate those 4 steps in lamest terms that would help.

Thank you all!

View attachment 157254
That is not quite the correct emission label for an L69, its likely an LG4 label. My L69 label says 600 rpm for curb idle in drive. Higher performance sub models sometimes have higher idle speeds than base models, Crown Vics are that way.

You set the timing by disconnecting the 4 wire to disable timing advance. Once done, you will need to clear trouble codes by disconnecting the battery.

To set curb idle, make sure the engine is fully warmed up, choke open, the computer is in closed loop, and the trans in drive, and disconnect the wire for the idle kicker solenoid. The curb idle screw is on the driver side of the carb.

To set the idle speed with the kicker extended either set the A/C on max or run a jumper wire to extend it, and thd trans must be in drive. The idle kicker solenoid is on the driver side of the carb, above the curb idle speed screw.

To set the fast idle speed, disconnect and plug the vac line to the EGR valve, make sure the throttle is on the high step of the idle cam, trans in park. The fast idle speed screw is on the passenger side of the carb.

All together, there are 3 idle speeds, cold start idle, warmed up idle, and heavy load (A/C) idle.
 
Supa.Slo.SS

Supa.Slo.SS

Not-quite-so-new-guy
Thread starter
Aug 7, 2020
20
3
CA
Not sure what gears you have, but once you have your timing set the best way to really wake that 305 up is by changing to lower (numerically higher) gears in the rear. This was the way GM did it for the Chevy 305s and Olds 307 HO.
Mac, I have the stock 3.42:1 rear end, however I do have a Grand National 8.5" Rear end that I will be installing at some point & I believe it has 3.73 gears.
 
Supa.Slo.SS

Supa.Slo.SS

Not-quite-so-new-guy
Thread starter
Aug 7, 2020
20
3
CA
That is not quite the correct emission label for an L69, its likely an LG4 label. My L69 label says 600 rpm for curb idle in drive. Higher performance sub models sometimes have higher idle speeds than base models, Crown Vics are that way.

You set the timing by disconnecting the 4 wire to disable timing advance. Once done, you will need to clear trouble codes by disconnecting the battery.

To set curb idle, make sure the engine is fully warmed up, choke open, the computer is in closed loop, and the trans in drive, and disconnect the wire for the idle kicker solenoid. The curb idle screw is on the driver side of the carb.

To set the idle speed with the kicker extended either set the A/C on max or run a jumper wire to extend it, and thd trans must be in drive. The idle kicker solenoid is on the driver side of the carb, above the curb idle speed screw.

To set the fast idle speed, disconnect and plug the vac line to the EGR valve, make sure the throttle is on the high step of the idle cam, trans in park. The fast idle speed screw is on the passenger side of the carb.

All together, there are 3 idle speeds, cold start idle, warmed up idle, and heavy load (A/C) idle.
Thank you Clone. I'll try see what it sounds/feels like at 500, but to you point i think it rather be above 600.

Question, what does it mean when it says "throttle is on the high step of the idle cam" .. do I have to rev the engine to a certain rpm? If so what is it?

Thanks
 
1983calais

1983calais

Master Mechanic
Supporting Member
Feb 26, 2015
275
63
Tiffin, OH
That cam is going to be a pig off idle, but should wake it up once the rpm's get over 3500.

Regarding the timing settings - no idea how to do it, but if you have 34-36 degrees of all in timing and it's not detonating/pinging, then it should be good.
I’m not sure where you’re coming from with this, but I have ran this same cam with 3:73 gears in a truck and it had all kinds of power down low, mid, and up top in the rpm range. I had the tune where it needed to be and it performed very well.
 
64nailhead

64nailhead

Royal Smart Person
Dec 1, 2014
1,417
113
Upstate NY
I’m not sure where you’re coming from with this, but I have ran this same cam with 3:73 gears in a truck and it had all kinds of power down low, mid, and up top in the rpm range. I had the tune where it needed to be and it performed very well.
Because that cam is a pig off idle in a 350 at 9:1. So lower compression and less cubes won't be an improvement. Especially with a stock converter.
 

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