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Topic Review (Newest First)
10-10-2012 02:44 PM
ggevaert
Torque converter

Talked to a couple of torque converter companies and they all recommended a 2400-2600 stall converter for my Cam specs. My local performance transmission shop recommended the same thing so I ordered a custom built 10" one for $500 bucks. Should be here early next week.

Now to the job of taking tranny out and once back together back to the disitributor and holley setup. Should also have the MSD 8365 later this week.

Cheers
10-08-2012 08:19 PM
ggevaert
converter

Hi F-Bird'88, Thank You for all the excellent info!
Now I know why the tranny guy explained to me that this was the best way to go. jeez.

I have attached a picture of what I have installed now; I could not find any info on what its specs are other than what the tranny company told me (1500 stall). I even looked at their bill and it does not list an actual model, only that it was a 'rebuilt torque converter'.

Anyway, I don't need it to be low rpm hiway cruiser, I was just wondering what I really have on my hands here. My goal all along is to build this setup the way it was meant to be; I acquired the engine as it is so now I am working towards maximizing it the way it was mean to be. If that requires putting in a 3000 stall 10" converter then that is what I will do.

Any recommendations on a torque converter company? Or maybe I should ask if there are any i should stay away from. I'll call a couple of companies and do some research. I'll call my friend who works the parts counter at the local GM dealer to see what he can get me in the GM line as well.
I have a THM-375 with a stage 2 shift kit hooked up through a BOP plate to the SBC 350.

Also, on the rear-end; I have been saving up to get that done as well; wasn't planning on doing it until later in the winter but may have to forgo that second coffee in the morning to get it in sooner. Currently it has the original rear-end in it from when the truck had a straight 6; in other words 2.73 rear end. So, what does that mean for driving it until I get that done? how will that affect the trucks driving manners?

Thank You

Gary
10-08-2012 12:00 AM
ggevaert
Torque converter

Thanks! I'll play with the timing tomorrow.
The torque converter is a bit trickier as I have to order one, drop to the tranny, blah blah blah, you know the deal.

I think I need to read up on the torque converter and how it works as I know the basics but not how/when it kicks in when you have a 1500 vs a 3000. i.e. does putting a 3000 in gear do nothing when the idle is at 1000 or does the car try to move (my 1500 will try to move). Do you need to be reving at 3000 (or close to that) before the car starts the move. Not that familiar, yet, with workings of the torque converter when it comes to actually when they engage. Another area for me to read up on; exciting!
There was probably a good reason why the engine/tranny combo came with a 2500 stall.
When I destroyed the tranny pump, and therefore parts of the tranny, through improper spacing of the torque converter (another lesson learnerd) the tranny shop recommended/put in a 1500 unit. But they never asked what engine setup I have. jeez.

I did not pick the specs on this engine so what's the deal with this setup F-Bird88, is it a street/strip type of setup or more agressive than that?
I do want to be able to drive the setup on the road and I'm concerned about the high stall.

Thanks for all your continued help!

Ps. the mech advance stop will be much easier when I get my MSD 8365 in
10-07-2012 12:24 AM
ggevaert
distributor

Thanks F-Bird'88, I'm going to check the advanced weights but since the whole distributor is new I don't think it would be warped; then again you never know.
I am more convinced now that the pro-billet (made in US of A) is the way to go. I read an article about a week ago where MSD was indicating their streetfire was chinese made and was their attempt to stay in the market they were losing to low cost alternatives. The way I read it they were pretty much apologizing for the lower quality of the unit.
Personally I don't like to scrimpt on certain things and the streetfire was a mistake so I'm going to correct that with a pro-billet. I already have a friend who will take the streetfire off my hands for a stock application and he will give me 90% of the units value so that helps.

I have multiple threads but they are not related. One is for mechanical advance (this one), one if for holley setup - transfer slot and one is for Holley setup - Choke. I guess you could say they were all related to engine tuning but I personally like to keep subjects separate as change-of-topic questions get lost in the discussion sometimes.

As for Cam shaft and torque converter specs; they are:
Cam: 450 lift, 224 duration, 206 lobe centre
Torque converter: new 1500 stall unit from GM - 2 years old now. (long story, had a 2500 in there and it went bye-bye when the transmission fried and now I have a rebuilt thm-375 tranny with 1500 staff as recommended by the tranny shop).

Thanks for the feedback, I guess my next step in this thread is to get the HEI Pro-Billet and go from there. I'll update how that goes when it comes in.

Cheers
10-06-2012 12:32 PM
ggevaert
Ongoing distributor saga

Hi SSmonty,

I tried swapping out weights with the advance kit specified from MSD for the streetfire and I didn't like it; the timing came in all at once at around 1800 (from 18 to 32 in about 200 rpm). All the different kinds of springs did was move the all-in point around but there wasn't a smooth curve so I went back to the stock setup. I have not played with shaving or changing the weights as that would be somewhat final so don't want to go there yet.

I checked the weights movement and there is no binding anywhere.

The MSD advance kit 8428 is the one I'm using now (since it is the one actually for this unit - the pro-billet kit was not)

I put a bright green line on the balancer since the day I got the engine and its still bang on.

I'm now actively saving up for a pro-billet unit but until that time I'm going to play with the Holley setup and maybe, when I have patience back, play with the ignition advance again

Thanks for all your continued help
Gary
09-29-2012 07:33 PM
ssmonty Sorry, I forgot to mention that I had to trim the bushings to get them to fit under the e-clips that hold the weights in place with the advance kit.
ssmonty
09-29-2012 07:12 PM
ssmonty Just my two cents,
Your distributor looks just like the MSD HEI Streetfire that I have laying around. I had issues with the advance mechanism not being as smooth as I thought it should be in certain positions. With no spring yours may let one weight get out in front of the other and bind(see pic,near thumb). I had to grind the end of one weight to keep it from catching. It may never have got to that position in normal use with springs. I'm just too picky(anal).
I swapped the weights out with a MSD Advance Kit PN 8428 and it seemed to be smoother.
However, I bought a MSD rev limiter module that was advertised to fit Stock and aftermarket HEI's, but low and behold it wouldn't fit in the streetfire????
I made a mod to it to get it to fit, but was still disapointed.
I decided to use an older MSD 8365 Pro Billet I had on another engine instead.
Something sure doesn't make sense with your timing being more advanced with springs vrs none. You sure the harmonic balancer outer ring isn't moving around on the hub(doubt it on a new engine)? Brush a thin line of paint across the two(from center outward) to be certain. You'll alwas know in the future if it has if the lines aren't straight.
I suspect the weights aren't as smooth as they should be, but thats just me. Might try the kit I mentioned.
Good Luck!
ssmonty
09-29-2012 10:29 AM
ggevaert
Stumped

Ok, I'm officially stumped and need some assistance. I'm using the MSD HEI advance medium springs. Initial is set at 17 degrees

1. with no springs and the stop advance screw in it stops at 36 degrees perfectly all the way up
2. With medium springs an NO stop advance screw I get 42 degrees at 4500
3. with medium springs and a stop advance is stops at 31 degrees all the way up.

huh? if the springs by themselves go over 36 and the stop stops it at 36 would that not have it stop at 36? I just don't get it.

I have played with over 3 different companies springs (Morose, MSD pro billet springs, MSD HEI springs and I have a mr gasket HEI kit on order). I have played with light all the way to heavy and numerous combinations of lights, mediums).

I made another screw and shaved it down to stop at 40; testing with springs showed it to stop, yup you guessed it, at 31.

I'm not sure where to look next. Any thoughts are appreciated.

I used a screw as the picture that F-Bird'88 sent, maybe another approach is needed? what are the alternatives (short of buying the pro-billet one with the built-in stop)

BTW, confirmed timing with another timing gun, a non-dial back light.

Thanks for any help
Gary
09-28-2012 06:03 PM
ggevaert
timing light

Thanks ssmonty,

I'll pull my old light out of semi-retirement and check it out. it has no dialback feature on it.

I actually went out and bought a brand new OTC 3367 last weekend because of the concern with MSD (and I needed one that would work with an MSD ignition box for my impala restoration).

I'll update when I compare the two readings tonight.
09-28-2012 04:40 PM
ssmonty Try a different timing light, one without a dial back function. MSD ignitions have been know to mess with lights, especially if its a dial back type.
Good luck,
ssmonty
09-28-2012 09:58 AM
ggevaert When I run the distributor without springs and with the stop screw installed (36 degree stop) it goes to 36 degrees but then starts to go backwards when I get above 3000; not an issue, just wondering why it does that? I went to 4500 and it went all the way back to 30 degrees on the timing tape. Interesting.
09-23-2012 10:25 PM
ggevaert
Springs

Thanks F-BIRD'88, I have already ordered MSD PN 8248 (the proper spring advance set for my distributor) which should be in tuesday and I'm also going to look into the mrgasket one you noted. I also found a moroso HEI spring set sitting around and tried it as well but still got stuck at the 32 degree mark. (although those springs were tiny compared to the pro-billet ones)

A couple of questions:
1. These kits come with weights, are these supposed to replace the weights in the distributor to work in conjunction with the springs included in the kit or are they only there in case you need new weights because the current ones are old/worn? I have a brand new MSD so the weights are working smoothly so I thought I would not need to change.

2. Can you elaborate on what you mean with
Quote:
"Check the free length when the spring is at rest. Check the weights for free movement"
.
I think I know what you mean with the first one; Some of the springs I did note were really tiny and I had to open them quite a bit to put them on so I can see them being limited. As for the weights; they are snug and not moving when I jiggle them at rest; they move smoothly out and snap right back. With 'free movement' do you mean they should not move (i.e. slop in them) when at rest or do you mean they move easily out and back?

Thank You!
09-22-2012 11:03 PM
ggevaert
Almost there

Ok, Almost there but still an issue.

Installed the mechanical limiting screw in my MSD Streetfire pn 8362 and confirmed mechanical advance now limited at 36 degrees. Confirmed it by taking the springs out and going up to 4000 rpm. Stayed at 36 degrees all the way up there.

However, after that I tried a number of different advance rate springs out (2 blues, 1 heavy and 1 light, 2 silvers) and all of them cause the advance to stop at 32 degrees all the way to 4500 rpm. (did not go higher than that). What gives?

Idle timing continues to be set at 18 degrees. (vacuum advance disconnected and plugged)

Do I adjust the distributor to bring it to 36 degrees? Would that not raise the idle timing to above 20?

Since without the springs it goes to 36 and with it doesn't the problem has to be in the springs I think; I'm just not sure how to resolve this. I want 18 degrees of mechanical advance on top of my initial advance.

So, on my thought of this being springs related; I used the springs from the Pro-Billet advance kit (the store had that in stock and not the one for my distributor so I took it thinking springs are springs) so I'm thinking that maybe those springs are not designed to work with my distributor and cannot stretch far enough. The pro billet advance chart shows them going much higher than what I need but maybe that is specific to the pro-billet and, on my distributor, they can't stretch that far so are limited to 14 degrees?

thoughts?

Thanks
Gary
09-10-2012 04:52 PM
spinn It is important to know how to do it yourself so you understand. F bird knows much and helps out with maximum verbosity. He deserves much thanks.

You can just throw money at it. For $70 4secondsflat.com will set up a distributor to any curve you want on the advance machine. Don, used to be very reasonable and fast return. Not to mention dead on accurate. Have not contacted them in over 10 years, but the site is still up.

There used to be tons of distributor shops that put the dizzy on the spin and suck machine. Now a days they are harder to find. Damn computers ruined everything except adult entertainment.
09-09-2012 09:00 PM
ggevaert
Mechanical Advance

Hello,

F-Bird'88, you are correct, budgets must be maintained!! I'll look into contuing with my unit and using your your picture and notes to fabricate a stop.
Is there a particular machine screw size/type you go with that I could start with? Or am I looking at putting it in, testing, then shaving it down some, testing, shave some more, test, etc. etc.

The VAC advance on my unit is NOT adjustable. I guess it used to be (based on the 2 different user guides for 8362 I found out there) and when I called MSD they indicated that, Yes, they changed their street-fire "value brand" to no longer have an adjustable can but they do include the vacuum advance stop plate. (see attached picture).
The MSD tech also indicated that the vacuum advance can with this unit will go all the way up to 22 degrees advance. It kicks in at 5 hg and goes up linearly, based on Hg, to the max of 22 degrees. The stop plate willl stop it at that range listed for the letter selected.
When I pull the distributor out I will also be installing that stop plate and I am going to set it at the B (11-14 degrees stop) so as not to exceed 15.

Also, I read a bit up on Phasing alignment but did not think it would matter to me as I have a brand new distributor so everything should be smooth and work great. Is there some sort of test I can do to ensure there is no phasing problems?

cdminter59, no box, just the streetfire GM HEI with incorporated coil.

Cheers
Gary
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