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Fasttrack
10-10-2006, 08:18 PM
Ok so here's what i did:
(400 cid Chevy small block w/ HEI ignition)

Hand cranked the engine over until the exhaust valve just began to open up (to find where the firing stroke was), turned it back an 1/8 - 1/4 a turn, then turned forward until my timing mark showed somewhere between 6* and 8* btdc. The tab was just a little bent so i can't be sure of exactly where it is, but it is between the two - closer to eight. Should it be higher? I understand that stock 400's are pretty low compression...but then its a truck and wouldn't often run very high rpm

Anyway, after doing this, i marked down from my dist. cap the number one firing post to the body of the distributer. I then measured 2.25" back from that mark on the body, rotated the rotor so the leading edge of the contact point was at the mark, inserted distributor with vacuum canister at about 45* across the engine. Then, i made a slight adjustment to the body so that the triangle shaped segments lined up (this only required a very slight movement). Then i clamped the dist down and popped the cap back on.

Did i do it right?

p.s. edit with timing advance - the line i was shooting for was marked "8*" and it was between that line and the line before it - i wasn't thinking and called the line before it 7* instead of 6* :)

Evan
10-10-2006, 08:44 PM
Does it run?

Fasttrack
10-10-2006, 08:55 PM
Lmao

I'll find out in a little while...i i've still got a bunch of body work to do before i can put my battery back in at which point i'll put the front end back on and hook up all the electrical and cooling stuff. 'Till then i'm just sitting here wondering! If it ran or didn't run i'd know i did or didnt do it right, respectively :D

wierdscience
10-10-2006, 10:46 PM
Doesn't HE ignition fire through 15* on the crank? Screw it,it's a Chevy,twist the distributor till it sounds right and run it:D

bob308
10-10-2006, 11:07 PM
trun the motor over by hand till #1 intake closes keep truning till the timing mark comes up on 0. pull cap and see if it is pointing to #1 if not set it so it is. that is the way i set all my motors up and they start right up. you mite also check the weights and lube the pins they ride on i have seen some worn half way through. a small block likes 28-30 deg. at 3000 rpm. the stock cruve in the hei is way too slow and some times has too much total advance

J. Randall
10-10-2006, 11:56 PM
Follow Bob's advice, should get you close enought to start and run, then fine tune it with a light. Sounds like you have it 180 degrees off, if you did it on the exhaust valve. James

Carld
10-11-2006, 12:10 AM
Yep, Bob's way is the normal way to set a distributor. Then use a timing light or tweek it by ear if you are a good mechanic.

Your Old Dog
10-11-2006, 08:14 AM
Does it run?

You are worth every nickle I paid to read this forum! :D

kendall
10-11-2006, 09:04 AM
Normally I'll pull the #1 plug, hand rotate the engine till I get pressure at the plug hole, slip a drinking straw into the plug hole and turn engine till straw just stops rising, then install distributor with #1 firing at that point. Very slight tweaking (needed with any install) gets firing dead on.

works for every engine you can slip a straw into and touch the piston, and has never failed me yet.

Last Chevy I owned was an '79 malibu, stupid $@##^%&^ thing burned out distributor pick up coils every 750 to 800 miles, could never find cause, but got so I could swap out that distributor and be driving again in less than 5 minutes, kept a spare in the trunk all the time, swap it, rebuild when I got home and be ready for the next time. was so 'reliable' that at around 700 miles I'd grab the distributor and wrench and put it on the front seat .

Was going to swap to points, but luckily the thing got rear ended and I managed to pick up a real car.

ken

torker
10-11-2006, 11:06 AM
Normally I'll pull the #1 plug, hand rotate the engine till I get pressure at the plug hole, slip a drinking straw into the plug hole and turn engine till straw just stops rising, then install distributor with #1 firing at that point. Very slight tweaking (needed with any install) gets firing dead on.

works for every engine you can slip a straw into and touch the piston, and has never failed me yet.

Last Chevy I owned was an '79 malibu, stupid $@##^%&^ thing burned out distributor pick up coils every 750 to 800 miles, could never find cause, but got so I could swap out that distributor and be driving again in less than 5 minutes, kept a spare in the trunk all the time, swap it, rebuild when I got home and be ready for the next time. was so 'reliable' that at around 700 miles I'd grab the distributor and wrench and put it on the front seat .

Was going to swap to points, but luckily the thing got rear ended and I managed to pick up a real car.

ken
Ken, that's how I've done it for years. Keep a piece of alu tig rod in my tool box for that all the time. If it's easy enough to get at you can also use a compression tester to find #1 TDC.
russ

Fasttrack
10-11-2006, 05:35 PM
I tried the straw trick (actually with a piece of plastic tubing) but becuase of where the #1 is located in relation to the brake lines and frame rail i couldn't use it very sucessfully. Thats why i did it off of the exhaust valve.

Someone else said i may be 180* off - here's my reasoning behind what i did. I turned the engine forward until the exhaust rocker just began to move. I assumed this would happen somewhere at, or near, the bottom of the combustion stroke. As soon as it began to move, i turned the engine the opposite direction, thus "re-entering" the combustion stroke - so to speak. I continued turning it backwards until my timing mark went beyond the tab and then turned it forward until the mark lined up with the mark for 8* btdc. Is this 180* off or is it the same as starting with the intake and continuing in the forward direction? Seems like it ought to be the same

According to Vizzard's "how to rebuild Chevy small blocks" the static timing for a sb with unkown static timing specs, one should set it at 8*. Should i keep it at eight or go to zero or go to more? The most i can accurately set static timing btdc is 16* advance or i think 6* retard. (possibly four or eight can't remember).

J. Randall
10-11-2006, 10:12 PM
Fasttrack, I think I understand what you mean now, you could have also just watched for your timing mark after the exhaust started opening continueing in a forward direction and turned it through another complete revolution till your mark reappeared, then you would have been on the firing stroke. As far as getting the static timing exact it is pretty hard. It will start and run anywhere from a few degrees retarded up to 20 degrees advanced or more. You need to use a light then anyway. James

kendall
10-12-2006, 01:10 PM
is that it can be used on any cylender, no real need to use #1, just remember which cylender you have an align the rotar wth that cylender.

another little 'trick' If you normally work on chevies, and need to rewire a ford, (or the reverse) 'renumber' the ford block like a chevy, then use the chevy firing order, most V8's use the same order, it's just that the cylenders are numbered differently

there are only two basic firing orders, the one used on 302's, and the one used on 351w, most chevies use the 302, and most dodges use the 351 order. there are oddities in each make (302 vs windsor for one) used to have a cheat sheet pinned to the wall for my less experienced mechanics.

Ken.

larry_g
10-13-2006, 12:45 AM
If you use this method then your perty wide open to missing the mark. The piston has virtually no vertical motion from 20 degrees BTDC to 20 ATDC. Your best off using the straw on the #1 cylinder and then bring the timing mark to the indicated point. Fasttrack it sounds like your in the ball park.
lg
no neat sig line

speedy
10-13-2006, 02:11 AM
Find TDC on 1,6,8 whatever. Lightly clamp dissy with rotor pointing to correct cylinder. Start engine bring up revs, move dissy in both directions till the motor begins to stumble then lock in midway position.
Take the vehicle for a drive till warm. Select a straight, flat section of road and in top gear at about 35mph apply full throttle smoothly. If it is flat then advance the dissy a tad and try again till you get the pink and it is just discernable and then disappears,if pinking too much just bring it back till the pink is just discernable and then disappears as your speed increases.

Oops, that should read 35kph; 20mph

Fasttrack
10-13-2006, 04:50 PM
Thanks guys! Hopefully i'll get some more tinkering time this weekend and i'll see what happens!