Classic Winnebagos & Vintage RVs

Topic Boards => Chevy - GMC Chassis => Topic started by: jeno on June 10, 2015, 09:01 AM

Title: which cylinder to use for timing 89 454?
Post by: jeno on June 10, 2015, 09:01 AM
i've been reading on the forum and it sounds like you use different cyl for timing i always thought i was number 1 cyl? i have never done this before so i have some questions. what should my timing be? i took off all the air pumps so what i have read the timing is retarded for emissions what would it be without it? if there is anything else you can tell me about the timing it would be greatly appreciated. as i said i'm trying to learn.
Title: Re: which cylinder to use for timing 89 454?
Post by: Froggy1936 on June 10, 2015, 04:33 PM
On any engine that has an even no of clys ( wont work on a 5 cly)the one opposite no 1 on the cap will give you the same timing readings Frank
Title: Re: which cylinder to use for timing 89 454?
Post by: jeno on June 10, 2015, 04:39 PM
so on mine can i use the number 1 cyl? and if i can is it the one on drivers side front or passenger side front?
Title: Re: which cylinder to use for timing 89 454?
Post by: gpw9552 on June 10, 2015, 04:44 PM
Use #1, Driver side front.  Google "timing a chevy 454" and there are about 4,000 + hits.
Title: Re: which cylinder to use for timing 89 454?
Post by: jeno on June 10, 2015, 04:51 PM
no#1 it is thank you i found on this site that 4 degrees btdc is the timing. is that still true with all the air pumps and everything off?
Title: Re: which cylinder to use for timing 89 454?
Post by: Rickf1985 on June 10, 2015, 07:37 PM
Number 1 IF you can see the timing marks on the right side of the pulley. There is another set of marks usually on the lower left that can be seen from under the drivers side. I forget which cylinder this is, it would not be #6 which is the opposite of #1. That would be on the upper left side. I want to say #5.
Another thing to consider is that if you disconnected the EGR then you might have detonation if you advance the timing. Just try it but keep a sharp ear out.
Title: Re: which cylinder to use for timing 89 454?
Post by: M & J on June 10, 2015, 08:46 PM
I think it is #5 Rick if theres a timing tab below. Theres a pretty good thread on it somewhere on the site.
But that way makes it a 2 person job.
Title: Re: which cylinder to use for timing 89 454?
Post by: Rickf1985 on June 11, 2015, 06:59 AM
Or one man if you need a lot of exercise getting up and down!
Title: Re: which cylinder to use for timing 89 454?
Post by: jeno on June 11, 2015, 11:41 AM
yes it has timing marks on the right side of pulley passenger side so number one it is. and yes i guess i'm going to get a lot of exercise. i did leave the egr on and connected. does anyone know what i should set the timing at with the air pumps off or should i just set it a 4 degrees btdc?
Title: Re: which cylinder to use for timing 89 454?
Post by: Rickf1985 on June 11, 2015, 12:17 PM
The A.I.R. will not change the timing specs. one way or the other. You could try advancing it a couple degrees to see if it runs any better. Just listen for pinging. If it pings you will have to back it off on the timing or run premium gas. At 6-8 MPG that could get real expensive when the alternative is to just back off the timing a bit and run regular. Or the other route is to go with a custom distributor timing advance curve that has been talked about on here.
Title: Re: which cylinder to use for timing 89 454?
Post by: jeno on June 11, 2015, 12:55 PM
ok will do ill let you guys know how it turns out. maybe ill get 20 miles to the gal. lol
Title: Re: which cylinder to use for timing 89 454?
Post by: legomybago on June 11, 2015, 03:49 PM
Our 1986 P30 454, I timed off the #5 cylinder, laying under the drivers side of the rig to see the lower timing marks I believe....been awhile.
Title: Re: which cylinder to use for timing 89 454?
Post by: Turbodime on June 15, 2015, 11:25 PM
Cyl #5 if using the indicator underneath.  Just went thru this process.  I used a sponge sanding block to clean up the harmonic balancer and cleaning it up made it more visible.
Title: Re: which cylinder to use for timing 89 454?
Post by: legomybago on June 16, 2015, 12:08 PM
 :)ThmbUp :)ThmbUp :)ThmbUp

You use ALL the length of your timing light power leads to reach...at least i did. Glad they make them long
Title: Re: which cylinder to use for timing 89 454?
Post by: Rickf1985 on June 16, 2015, 12:23 PM
Quote from: Turbodime on June 15, 2015, 11:25 PM
Cyl #5 if using the indicator underneath.  Just went thru this process.  I used a sponge sanding block to clean up the harmonic balancer and cleaning it up made it more visible.

You show two cylinders at each location when in fact only one will flash at each location. Unless you have distributerless ignition the cylinder only fires on the compression stroke. With late model distributerless ignition that has four coil packs there will be a waste spark on the exhaust stroke so you will get a strobe on them but timing is not adjustable on those engines so it is moot.
Title: Re: which cylinder to use for timing 89 454?
Post by: MotorPro on June 16, 2015, 12:59 PM
Yes the plug only fires on the compession stroke but since the crank turns twice for every turn of the distributor using either of the listed plugs will show the same on the crank. Timing lights only flash every second turn of the crank
Title: Re: which cylinder to use for timing 89 454?
Post by: legomybago on June 16, 2015, 01:22 PM
That diaghram is just showing what cylinder is firing 180* off in coralation to the balancer. Thats a great illustration of the lower timing marks for people who need this info. This should be bookmarked or something for users to find this info easily later on.
Title: Re: which cylinder to use for timing 89 454?
Post by: Rickf1985 on June 16, 2015, 06:12 PM
Quote from: MotorPro on June 16, 2015, 12:59 PM
Yes the plug only fires on the compession stroke but since the crank turns twice for every turn of the distributor using either of the listed plugs will show the same on the crank. Timing lights only flash every second turn of the crank

You know, for some reason I knew when I was posting that that I was wrong and the brain would not register it. I have been working on the modern stuff too much and lost track of the basics. I don't ever remember seeing a set of timing marks on the upper left side. Could be brain fade again though.
Title: Re: which cylinder to use for timing 89 454?
Post by: DaveVA78Chieftain on June 16, 2015, 06:19 PM
Thats why we work on all this older stuff.  Keeps the brain fresh
Title: Re: which cylinder to use for timing 89 454?
Post by: TerryH on June 16, 2015, 07:21 PM
Kinda figured you'd spent the day in the bucket truck in the sun when you posted that, Rick. :'( :'( :'(
Title: Re: which cylinder to use for timing 89 454?
Post by: Rickf1985 on June 17, 2015, 07:01 AM
Actually bucket truck will be today. Got a hundred foot lift coming in next week, I sure hope it does not rain! I don't know what they are going to do when I retire, I am the only one here not afraid of heights. i?? When I am doing that work it clears my mind and I think better.

Anyway, If you time off of number 5 plug then the timing leads are plenty long enough since it is right in front of the block on that side.