The Stovebolt Site Forums The Shop Area Engine Shop HEI.....UNK.....and I.....its alive!

Well...."we" installed the Langdon's HEI after two years frought with other problems on "our" truck. Bumped the startrer and it roared to life.....very cool...put smiles on both of our faces!! We are still fooling with the timming right now we are at 550- 650 rpm vacuum at 18.5 and the ball on the fly wheel( with timming light) about 5/8 of an inch to the left of the pointer. Since we are both hard of hearing we think there might be just a little pinging with foot into it on a very long steep hill??? Do these numbers seem right? The thing goes like a bat out of the bad place...(GOD Bless Mr. Langdon) MAN what a difference....OK let me know what "we" should do next on the timming and t/c Steve

Congratulations to the dynamic duo from CA!!!

Sounds like you have the timing about right. A slight pinging on a long steep hill is normal (in my opinion) for the best in performance and economy.

Good job guys.

THANKS ..."we" could not have done it without your help! T/C Steve

We are a skeptical lot here on the Bolt and would like to see proof of all this!
Where are the pictures?

Who,Me- congrats on stepping up to modern technology. I have Tom's very first mini unit in my 46 and it's been super. Have not had to touch the thing other than the usual cap and rotor. Tom's instruction sheet suggests 10 to 18 deg (with vac. adv disconnected) also recommends wider gap on plugs.
Get the thing where you like it then head UP Greenwith St. hill in the city and if you make it to the top you're ok.

Also, I've home built another mini and it's not worth the hassle, Tom's prices can't be beat.

Hey...I would post pictures but I have no idea how to do it and my wife owns the camera.... I still have my brownie box camera and have trouble with that! I'll speak with the boss and see what she can do as far as pictures....?

Yep Tom is a very nice fellow also and stands behind his products. I thought about making the HEI dizzy also but you are correct. Tom's price is too good to beat and its very well machined and a great hold down also. Well you guys have me 10 to 18 degrees but the fly wheel is not marked that way so I have no way of getting to those numbers.YES...I did 60 on the plug gap. I just used vacuum gauge 18.5 and RPMs550-600 at idle and let the BB sit at about 5/8" left of the pointer... does that location of the BB to the pointer sound right as I really have no idea where it should be its just a guess I'm open to all suggestions! Steve

Hey Steve;
When you say 5/8" left of the pointer are you meaning 5/8" below the pointer? Or maybe your '55 has the pointer in a different location than my '54 which is just above the starter (?)

I've got mine timed so that the BB is just starting to appear in the "hole", below the timing arrow, so I'd say 5/8" below the mark is just about right. Does that make sense?

Well..my engine is a 55-57 model and the "pointer" (timing arrow) is in the middle of the hole that's above the starter and the BB on the flywheel is about 5/8 of an inch from the arrow (pointer) LH side of hole not below it. LH edge of hole--->( BB-5/8-I<--pointer)<-----RH edge of hole....make sense? What do you think pretty close? Steve

Just got a PM from Mr. Langdon he says move the BB on the flywheel to the LH side of the arrow pointer and try it there to see if it pings....back to the drawing board! Steve

I am pretty sure if you use one of the newer timing lights that have the adjustable timing, you can set it(the light) to the 18 degrees and reset your distributor back to the BB.

I too have the Langdon HEI kit in my '50 3100 on a '60 235 car engine. I rebuilt the engine and added a 3/4 race cam from Patricks to the dismay of Mr. Langdon. I've run the engine three times in the past couple of months and have tried to set the timing by ear per Mr. Patrick's advice (difficult having never heard one of these engines run before) and with a timing light. I think I got my engine at a fast idle to about 5-7 degree before top dead center before it started to stall out. I backed it up slightly and it runs well.

I don't know how anyone can get it over to 18 DBTDC. Aren't you supposed to set the timing at a specific RPM, like 2,000 RPM? That's how we used to do it with the more modern cars like the '79 MGB or the '78 Land Cruiser.

I called a buddy of mine up and he has an adjustable timing light that he got from his step-dad...GREAT...but he has no idea how to use it...is there a quick course guide out there? We did a search but its all tech speak....any help would be appreciated! Steve

Steve,

The adjustable timing light is just a timing light with a calibrated dial. Hooks up the same and works the same.

Make sure the dial is set at zero.

Shine it at the pointer hole, now turn the dial and watch the BB move to where you want it. Then read the dial, it will tell you the number of degrees.

Tom thanks will give it a try this weekend. As we understand it you point it at the timing arrow pointer and make sure the degree wheel is on zero and that the BB on the fly-wheel is at TDC and is lined up with the arrow pointer. When those two line up then move the dial to the degree number you want(which changes the strobe pulse) then rotate the dizzy until the two marks line up again and that gives you your degree numbers...agree? T/C Steve

If the flywheel BB is about 5/8" "to the left" or below the bell-housing pin, that would be about 5 degrees BTDC. The BB is in the flywheel at about a radius of 7", so that would imply that there would be about 8-3/16 degrees per inch at that location (360 degrees/(2 X 3.1416 X 7") = 8.185 degrees per inch). Is the BB at TDC? My 1955 shop manual indicates that it is.

Since the hole in the bellhousing is only about 5/8" on either side of the pin, you cannot set much more advance with a convetional timing light. Timing marks and a pointer could be added to the crankshaft dampener pulley, or use one of the new "adjustable advance" timing lights, as mentioned by BigSix302.

How much total centrifugal advance is in your HEI distributor from Tom? The 1955 shop manual says 12-14 distributor degrees for the 1955 engine. Thus (for the 1955 distributor) the total timing would be 29-33 crankshaft degrees with 5 degrees of initial advance.

I also have a Langdon HEI. I bought it on ebay.

How do you hook up the two wires that come out of the distributor?

I got the whole kit including the round f*&d coil, but I didn't get the instruction sheet. I have a scanned image of it but parts are unreadable.

Thanks,

Bill.....the pink wire goes to the + side of coil along with your 10 ga. ignition wire to your key switch. The brown wire goes to the - on the coil. You need to change your coil and plug wires also the wire that goes to the key swich (10 ga.) and take off the ballast resistor on the fire wall also spark plugs are a diffrent type. If you shoot Mr. Langdon an email with any questions he will always answer. T/C Steve

Hoyt....we used an advance feature timing light and got our 10 degrees advance which is on the RH side of the timing pointer. Mr. Langdon said 10 to 18 degrees and our truck runs great at 10 with 18 vacuumm. You are correct without an advance feature timimg light we were up the creek. What was confusing were all the terms and what they equaled (not just before top dead center and after top dead center) but also BTC=retard....ATDC=advance...once I got that ( a big bag of DUH ). It sort of all came together ( with the help of a lot of people on this forum) with the advance feature on the timing light....T/C Steve

Ok guys and gals you have me wondering now....what is a good ignition curve for a BONE stock 1955 235? The books I have say something like about 2 degrees btdc which dont seem like very much? I guess let me put it like this,

when the ball is centered on the bb,is that TDC

what would be a good initiall setting?
how much mechanical?
how much vacuum?
for a total of?
and what RPM would you want it all in by?

I know from experiance most all engines can be made to perform better whith a better ignition curve set up than the factory had.

Mr. Goodwrench,

I don't know if this pertains to a '55 engine, but on a '51 235, when the ball is on the pointer your ignition timing is 6&deg BTDC.

I think this is correct!

Stuart

Octane levels of gasoline used to be a lot lower when the shop manuals were written for these engines.
With todays higher octane gas, timing needs to be advanced.

Timing should always be as much advanced as possible (leanest setting) before pre-ignition or detonation can do any damage.
This will also give better mileage and improved acceleration.

I always let the engine tell me where it likes ideal timing.
Forget about the flywheel marks and timing lights.
Just keep advancing (turning dizzy counter-clockwise) in small steps until you get slight ping at WOT going up hill in highest gear.
Then just back off until pinging goes away.
This gives ideal timing with any octane gas and at any altitude.

Recurving the distributor and/or vacuum advance is not required with mostly stock street engines, unless you have a race cam and go beyond 3000 rpm a lot.

Mr Goodwrench,

Here are the stats from back in the day. 55 truck wasn't listed.
This should give you an idea.

55 Car

54 Truck

On our engine the ball on flywheel is TDC its a 1955-57 engine code....so we have been told?