How to Lock Out the Timing on an HEI Distributor - A Complete Guide

[@richardsmith-qy6vl]

That was the easiest way I've seen to lock out a distributor. Wow good deal.

[@MarkDHall]

Great to hear! Glad it helped. Thank you for watching!

[@IT3Mack]

I was having the same problem with a thumpr cam and to big of a cylinder head combo, i ran an adjustable vacuum canister and was able to dial in 32* initial with 42-48* part throttle highway cruising with the vacuum canister and total of 37 at WOT with the mechanical advance, im going to lock out my HEI now though. I picked up a 6AL-2 and can digitally program everything now which is more accurate so the video has helped with that. Thanks!

[@MarkDHall]

Hi Mike. I'm sorry I didn't reply sooner. I'm not sure how I missed your message. Glad the video helped! If the lockout didn't work, Matt was going to get a new ignition box/distributor. Thanks again for watching!

[@blakerodriguez5999]

Great stuff guys. I have a gm847 cam in my carbed lt1 and I am dealing with some nasty spark knock if I have my timing set to what I want on initial. Going to lock out my dizzy thanks you to!

[@MarkDHall]

Keep us posted! I hope it helps.

[@blakerodriguez5999]

@@MarkDHall it worked! I did the zip tie method though. I appreciate the video!

[@Nomad-376]

Been looking for this !!! Thank You ! Subbing now

[@Nomad-376]

Do you set timing before or after this ?

[@MarkDHall]

I know Nomad. You want to put the engine at top dead center, drop in the distributor, and then set the timing. Hope that helps.

[@sepasgozar]

If advance curve doesn’t change while the rmp increases, doesn’t damage the engine at all???

[@MarkDHall]

Hi! I'm so sorry for the slow reply. I wanted to check with Matt about this and totally forgot to reply. He said - as long as you don't go too far, it shouldn't be a problem. He locked it at 36 degrees. Most cars advance the timing automatically when the RPM increases. Matt wanted more timing at idle, and that's what this does. Many distributors have the lock-out capability built in, but they're expensive and Matt didn't want to spend the money. Thanks for watching!

[@sepasgozar]

@@MarkDHall . Thanks for getting back to me. I am still wondering if the advance curve fixed on 36degree, so 36degree crank advance during idle won’t cause any fireback or engine damage??

[@MarkDHall]

We haven’t had any issues, and it’s been this way for a couple years.

[@johnfinley4024]

I'll be doing this tomorrow. BBC solid roller nitrous cam. Just can't get things adjusted with the lower timing. Runs a little rich and won't adjust out. Dosen't seem happy with base timing in upper 20s. I am running an msd box that has start retard so it should work good. Thanks

[@MarkDHall]

How did it turn out? I hope it worked. Matt had the same issue and said his timing needed to go higher. Internet research said to try this, and thankfully, for us, it worked. Hope it did for you too!

[@johnfinley4024]

@@MarkDHall it made it happier. Was blacking the spark plugs and make you sick with gas fumes. It's good now. My buddy I bought it from ran crank trigger ignition with a locked distributer. So basically the same deal. Thanks

[@MarkDHall]

That's great. I never heard of having the timing so high, but Matt was like, "Yeah, that's what it needs."

[@johnfinley4024]

@@MarkDHall I locked it on 35,36 and it idles much cleaner now. I have an msd box and it will retard timing 20 degrees for starting. Soon as the engine hits 800rpm it goes back to 35. Keeps it from kicking back.

[@MarkDHall]

@@johnfinley4024 Sounds like it worked perfect. Matt was too cheap to get a box and is thankful it's working properly without it. His engine is low compression, so that may help, but I imagine it wouldn't work with a higher compression one.

[@ProjectHuntBowhunting]

Hey man great video! I’m running a custom grind isky cam in my 355 sbc, and I’m having advancing problems as well and imma lock my distributor out as well. I will probably weld mine though. My build is also on my channel as well man. Thanks again!

[@MarkDHall]

Thank you for the kind words. Sorry I didn’t see your message sooner. I’m going to go to your channel and check out your engine too. I think welding is probably a better option, but this seems to be working OK so far.

[@tylermease8465]

Great video Thanks for sharing ! 😁Were there any big improvements ??? What did you set your vacuum advance at?

[@MarkDHall]

Hi Tyler. Thank you for watching! The timing is set at 35 degrees. There is no vacuum advance. The improvements were huge. Very snappy and great throttle response.

[@Nomad-376]

Should help with cams at or more with 240 @ 50 , burning rich at idle . Correct ?

[@MarkDHall]

Yes. It should run cleaner at idol.

[@RTROME]

So did you set the 35 degrees of timing at idle ?, or at 2500 to 3000 rpm? I have the same HEI, on a sbc 350 running a Comp cams Thumpr and was thinking of doing the same thing , nice video BTW...

[@MarkDHall]

Hi Ross, thank you for watching. We set the timing at idle, but because the timing is locked, it stays the same at all RPMs, so I don't think it really matters at what RPM you check it. In a normal distributor that's not locked, the initial timing at idle is less than the total timing at a higher RPM. As the RPM increases, the weights expand, which advances the timing, but because the weights are locked in place with this setup, the timing will stay the same throughout the RPM range. The cam we have is also a Thumpr. It's a 305, so yours is going to be a lot more powerful. I hope this answered your questions, but if not, please let me know. Thanks again!

[@RTROME]

@@MarkDHall Thanks for the response and it makes sense... I have a spare HEII, so I will try this , !!

[@wyatthull6613]

Your mantle totally reminds me of boogie nights.

[@MarkDHall]

That's funny. Thanks for watching!

[@Bekind1980]

So you locked it fully closed so it won't open at all ?

[@MarkDHall]

Correct. It's locked so it won't vary from the timing that's set. If for instance the timing is too advanced and we decrease it, it will always stay at that new decreased setting. It won't increase or decrease automatically as they normally do.

[@toddhill2362]

Um... you pulled that out at TDC?.... Was that locktight you put on those screws?... or no

[@MarkDHall]

Hi Todd. I checked with Matt, and he said "yes" he pulled out the distributor at TDC. You also want to put it back in at TDC. I watched the video and didn't see Matt put anything on the screws, but when I asked, he said he put Loctite Blue onto them. Looking back, I should have noted those two things in the video.

[@jacobjarvis2545]

? Are you droping the distributor in on the zero mark at tdc or 34 degrees before tdc

[@MarkDHall]

Hey Jacob. Yes, drop it in at zero and then adjust from there.

[@jacobjarvis2545]

@@MarkDHall thanks for the reply i just did this today i had the wrong timing tab on so now its 32 degrees at the 12 o'clock position

[@MarkDHall]

@@jacobjarvis2545 Sorry for my slow reply earlier. How’s it running?

[@jacobjarvis2545]

@@MarkDHall best it ever has

[@MarkDHall]

Glad you got it figured out. Sometimes it takes some trial and error to get it right.

[@Mattndew676]

You don't need anything aside from the spark module for this? no ECU or CD Box?

[@MarkDHall]

Hi - Correct. No ignition box or anything extra needed. Thanks for watching!

[@lynndragoman2454]

Why not pull off the vacuum canister as well?

[@MarkDHall]

I asked Matt, and he said he wanted to leave it on (maybe if he needs to use it in the future?), but he said it's not functioning.

[@poulfrascini4927]

Should have drilled the holes while holding the distributor in full advance. When the cap and distributor were being designed they was expecting it to spend more time advanced so that's where it will work better. Maybe I'm just nit picky with mine but that's what I do.

[@MarkDHall]

Hi Poul. Thank you for watching. That's a great suggestion!

[@stratdude83]

Why would it work any different in full advance or not? It shouldn't make any difference at all

[@brawler3475.0]

Instead of using the screws you used why not just use rivets it would make for a lot nicer end result

[@MarkDHall]

Matt thought that but figured since it's only visible with the cap and rotor off he'd just stick with screws.

[@maxxmasson4263]

good idea

[@objectionhearsay4102]

If you take the weights off and switch sides with them it does the same thing without drilling it

[@MarkDHall]

Hi. I can’t speak for other distributors, but with this one, that doesn’t work. I know some higher end MSD models have the capability built in, but you need an ignition box.

[@Fritsvrolijk]

Thanks pro \

[@MarkDHall]

You're welcome!

[@Llothedon1]

Isn’t it easier to just plug vacuum canister

[@MarkDHall]

Hi Truckin. This is for mechanical advance, not vacuum advance.

[@davidvonanderseck8649]

Why not just take the weights off

[@MarkDHall]

Would that actually work?

[@davidvonanderseck8649]

Ya I just locked mine out. I bought the "kit" .... All it was, was a plate that about 3/4 wide and 3 inches long with 4 3/16 holes that are inlined with eachother. You could make pie easy. Except o spent 25 dollars for mine.

[@MarkDHall]

@@davidvonanderseck8649 Thanks! For some reason I think Matt read that wouldn't work with his distributer, which is why he did it this way, but that was awhile and I'm old, so I may not be remembering right.

[@bartbarnett2811]

I don't understand the point of locking out the timing

[@MarkDHall]

Hi Bart. Some camshafts like a lot of initial timing at low RPMs, but with most distributors, if you set the initial timing higher, you'll have way too much total timing as the RPMs increase and the timing advances. This can damage the engine. When you lock the distributor, it keeps the timing consistent at all RPMS. Its easier to lock the ignition timing and just keep it the same at all RPM ranges instead of having to limit the amount of mechanical advance and adjust your timing curve throughout the RPM range. Certain distributors have the capability to lock the ignition timing, but they are expensive, and we didn't have the money to buy one, so this is sort of a "poor mans" way to do it.

[@donefedup2208]

lets have a look at your girl friend why ya stick that cap back on

[@MarkDHall]

No girlfriend in the video here. That’s mom. You have to put the cap on so the spark plug wires have a place to go.

[@perrywright4624]

Turn the weights upside-down

[@MarkDHall]

Hey Perry. What does that do? Does it help?

[@perrywright4624]

@@MarkDHall did lock the distributor out within 2 degrees

[@MarkDHall]

@@perrywright4624 Thanks!

[@davidrowland2354]

Why would u wanna do this?

[@MarkDHall]

Some camshafts like a lot of initial timing at low RPMs, but with most distributors, if you set the initial timing high to start, you'll have way too much total timing as the RPMs increase and the timing advances. This can damage the engine. When you lock the distributor, it keeps the timing consistent at all RPMS. Its easier to lock the ignition timing and just keep it the same at all RPM ranges instead of having to limit the amount of mechanical advance and adjust your timing curve throughout the RPM range. Certain distributors have the capability to lock the ignition timing, but they are expensive, and we didn't have the money to buy one, so this is sort of a "poor mans" way to do it. Hope this helps, but if not, let me know, and I'll try to explain it better.

[@J.Ogden954]

Why not just tack them with a welder?

[@MarkDHall]

That’s a great way to do it too, but we don’t have a welder. Wish we did, though!

[@davidrowland2354]

I bet its hard to crank

[@MarkDHall]

Hi! It's actually not. Turns over and fires up in 2-3 cranks is all.

[@davidrowland2354]

@@MarkDHall my experience has been if you put too much initial timing it makes the motor hard to turn over

[@MarkDHall]

@@davidrowland2354 This is the only motor we've done that too, so we don't have anything to compare it to. Does compression make a difference? This is a pretty low compression motor. Maybe that's got something to do with it?

[@davidrowland2354]

Is it hard to crank when it's hot

[@MarkDHall]

@@davidrowland2354 It's not really hard, but it can take a couple seconds. I forget what Matt said it was, but it's not vapor lock.