wmf62

Bob & everyone....
it seems like i have the opposite problem as you described it. i originally had the narrow window shutter wheel (the one in the picture with the optical sensors laying in the bottom). the replacement distributor i got from Summit had the wide window, and i used the same phasing instructions as for the narrow window distributor (Accel INSISTS that the setup instructions are the same for both distributors). it was probably then that i started experiencing starting problems (it seems like it has been going on so long that it has been that way forever.., so i really don't know for sure...).

anyway, i rechecked/rephased the wide window dist and there was still no change in starting. i then removed the circuit board from each and checked the difference between the 2 distributors and it appears the trailing/leading edge position of the inner ring relative to the outer ring is different (look closely at the pictures of the shutter wheel in each style of distributor). so, out of frustration, i decided to install my other dist (the narrow window replacement from Accel for the one that came apart..) AND, at the moment, the starting problem has gone away..... just dumb luck....

and so the question still remains; what is the real difference between the 2 dist styles, and do they really have different setup requirements (remember, Accel says there is no difference..); or is there something wrong/out of adjustment with my wide window dist... ????

IF my starting problem is really solved, i now need some help in getting the tuning right..



Bill

Bullshark

I don't see how Accel is saying they don't have different setup procedures when they themselves published two different sets of directions. You got copies of both didn't you. How did they explain that?

So, the bottom line is that the old (wide cam sync window) style distributor was setup using the new setup directions....right? You now took the new (narrow cam sync window) style distributor setup using the new directions and everything seems to be working fine. That's not opposite???? I think that is what we (I) was meaning to say all along. Anyway its good you have all this behind you.
When you get around to drop kicking that old style dizzy out of sight, Kick it my way. Ok.

wmf62

Bob
i can rarely get to talk to a Accel tech support person, so i haven't heard that directly from them; but the guy i got my stuff from (and i asked him the question) says he talked to them and was told there is no difference...

and a guy that i paid to do some tuning for me says the same thing...

Bill

Bullshark

Oh.....You know what my answer to them is don't you? .....

wmf62

yes....

do you know how to use the VE table estimator utility?

weez58

Bill,

That's great news that you have the starting issue cleared up. Have you tried using the Ve table estimator? As I recall it was self-explanitory. The only hassle was trying to come up with the cam timing info it asked for.

-Bob

wmf62

what i meant by opposite was, you went back to the wide-window dist & i went back to the narrow-window one....

now i need to try to figure out how to upgrade this dist to the new shutter style so that i have a good spare...

wmf62

Bob
yes, it's self explanatory, kinda sorta; it's figuring out how to determine the 'intake valve closing angle', 'intake valve lift', 'total runner length', etc when you don't have the foggiest idea what they're talking about in some cases...

i did plug in some values that we thought might be right, but it generated a table that was very different from the one that the tuner came up with...
Bill

weez58

Bill,

I agree. My VE table doesn't look much like the one that was generated by the estimator.

-Bob

Bullshark

Bill,
I wouldn't worry about trying to generate an estimated VE table. It sounded like you already have it started and running. After you install the LC-1 wide band O2, its just a matter of going through the table at key points and using the autocal function to set VE table values based on your selected A/F table. Then do some curve fitting / smoothing across the table for uniformity. You can always double check various points (cells) to fine tune the map. So, the next question is what A/F table does one use. That depends on what you want! Performance or economy. I suggest you setup one around the guidelines suggested by this FAST A/F instruction graph below as a good starting point. Don't forget this graph is in vacuum psi coordinates and would need to be converted to KPa



Bullshark

Bullshark

One more important tip though, Make sure you let all the fuel transient modifiers settle out and are fully up to operating temp before you do any adjusting. You don't want to skew the values due to accel enrichment, etc. etc.

Bullshark

wmf62

Bob
your A/F chart is about what i would expect, thanks.

my problem is trying to get the A/F, VE & ignition timing tables all synched within a relatively small rpm range window because i am running a 3:36 rear gear AND have a 0.73 OD. as a result, i run down the road at 70 -75 at approx 2250.

right now my mileage REALLY sux, with no more than 17 on the road (today i topped off and only averaged 12.7 for about a 50/50 mix of town/highway driving ), whereas with the rochester FI was i able to get well over 20 on the highway... something isn't right, i should be able to do as good, or better.

can the VE auto cal be done under no load, or must it be done while driving?
Bill

Bullshark

You can do a few of the cells under no load, but you won't be able to do the majority of the table without varying the map value. Which means under varying loads.

wmf62

Bob
i've got to do something about the mileage, the latest is 15.5, and that sux...

when doing the VE auto cal, should that be closed loop or open loop?
Bill

Bullshark

Closed Loop. Use A/F ratio numbers on the higher side of the ranges in the above graph.

wmf62

Bob
are the numbers in the individual cells of the VE table larger or smaller for leaner?
Bill

Bullshark

Smaller

wmf62

Bob
OK, i've bumped my A/F ratio table to various values (depending on 'sweet spot' MAP values at various rpms) from a low of 14.20 in the 250 column to a high of 14.90 in the 1800 column, and 'leaned out' my VE table by making auto cal changes at steady state rpm values (non-driving) in each appropriate rpm column cell (and then interpolating each of the columns using these values, and then going back and interpolating each row to get a final table) to the ragged edge of a bit of surge/miss. i have then used this VE table to check for driveability and mileage. so far i have increased the entire table twice by 10%, then decreased it by 5%, and then increased by 2%... (may have to go 1% more....)

are there any other adjustments that can be made to squeeze a few more mpg out?
Bill

wmf62

the following is what Accel now says about setting up the 2 different distributor styles:

Hi Bill

The shutter wheel is not the problem, there are two different installation procedures for each distributor.

1) If the red light stays on after the blue light shuts off, you have to keep rotating the distributor until the red light shuts off, turns back on and off again; that is when you lock the distributor down, than you would phase in the rotor at 25deg BTDC #1.

2) If the red light is off after blue light shuts off, keep rotating the distributor until the red light goes on than shuts off ; that is when you lock the distributor down, than you would phase in the rotor at 25deg BTDC #1.

Depending on the light sequence, you the proper instructions.

Have a great day

Elie Nahed

Sales Manager - EMIC Program Manager

Bill

Bullshark

Bill
I think this is just a different way of saying the same thing we have said all along wrt Accel's published directions. NO new news here. BTW, the shutter wheel was your problem since it was setup wrong.

Bullshark