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MikeKanterakis
01-19-2005, 07:33 PM
Can someone please help me decifer this e-mail from Art Carr transmissions? thanks. Specifically, what is flash? and why won't that use the car as well?

The "Mileage Maker" converter is designed for offroad, 4WD,
pulling, &
highway use. It will give you better fuel mileage by lowering
the stall
slightly below stock. You gain fuel mileage but the stall is
lower.
When you accelerate, the converter won't flash as high so it
won't be
utilizing your cam's power range as well.




Edit: Given this setup, wouldn't a 3.73 rear-end help satisfy this problem? At ultimate cost of top speed, but none the less...

Dirtyd0g
01-19-2005, 07:37 PM
Flash is how many rpms the converter allows the engine to jump to.
Do this get in your car put your foot firmly on the brake and then put it in gear.
Snap the throttle to the floor and the rpms will rise fast. Lets say you have a 2200 stall converter. It will generally flash to about 2400 and settle in about 2200 provided the wheels don't start moving. Bringing up the rpms slowly will not get the flash out of the converter. I hope that made sense, it is much easier to show somenone.
Alan

MikeKanterakis
01-19-2005, 08:20 PM
Thanks for the reply. So you're saying that it's that "slack" you see on the tach. when bouncing in and out of gear as you're cruizing along on the highway?

Bouncing in and out of gear by either pressing on enough gas pedal to cruize along, or to pull your foot off the pedal and let the rmp's drop. ???

Dirtyd0g
01-19-2005, 09:01 PM
Bouncing in and out of gear?
How much stall do you have?

MikeKanterakis
01-19-2005, 09:09 PM
now, i'm not sure... what did you mean when you said : Bringing up the rpms slowly will not get the flash out of the converter.

Dirtyd0g
01-20-2005, 01:04 AM
now, i'm not sure... what did you mean when you said : Bringing up the rpms slowly will not get the flash out of the converter.

Easing the throttle down instead of shoving it to the floor

MikeKanterakis
01-20-2005, 01:03 PM
so, the more flash you have, i.e. the higher the stall, the more engine rpm you'll have towards your launch. But, this lessens fuel economy because you're revving the engine higher and using more engine power to take off faster. where by a lower stall, would give you less take-off / launch power, but would keep the rpm's nice and low, there by saving on gas?

Then, a change in the rear gears would keep those rpm's low, but now, you wouldn't need such a high stall b/c the engine doesn't have to work as hard in order to cruize down the street.

?

Dirtyd0g
01-20-2005, 01:16 PM
Smaller converter flash considerably high than larger converter. It all has to do with pressure building up in the turbine. For example if you have a 2200 stall 12 inch converter it will flash to about 2400. If you have a 2400 stall 9.5 inch converter it will flash to about 2800. The 10 inch units I build stall about 2500 and flash to about 2600, but that is because i close up all the leak points and trap the fluid in.
Alan

MikeKanterakis
01-20-2005, 02:13 PM
ok, i've read some more about torque converters, and came up with this. Basically, you need to match the torque converter to the engine's peak torque rmp, as well, as the gearing in the differential. This way, you use the converter's torque multiplying properties up the the point where the engine takes over in terms of peak power.

I'm rebuilding my wife's SC as a stock + car. By that I mean, that I want to run it in it's stock configuration, but if I can ease some stresses inherent in the system, then that's the plus part. I.e. add a tranny cooler, install a different power steering cooler (yes, i've been meaning to post that for ever, but I'm slow.), replace the air dam with the pontiac air dam, etc.

So, when I saw the listing for this Mileage saving torque converter, I got all excited. But, it seems that, really, all I can do is match the torque converter to the system, and that's about it. Therefore, do you, Dirtyd0g, or anyone else, have a recommendation for a good light-weight torque converter with a stall matched to the stock setup? Howabout a match for 3.73 gears?

Damn, I thought I was done with these messy automatics when I got my 5-spd. Oh well. Wish they made a clutch light enough to satisfy the wife.

Thanks for the replies Dirtyd0g. I appreciate your making me more informed. Between the advice I get here on SCCOA, and this rebuild project with my wife's AOD, I'm on the road to SC enlightenment! Pretty soon, I'll get to the mountain were all the people wear robes and talk about that silly little puzzle called the internal combustion engine. he he he he he

Dirtyd0g
01-20-2005, 06:30 PM
For a stock engine go with a 2200 stall non lockup converter.You just missed it I sold a couple of those. Bill Evanhoff @ SCP sells the ones I build very reasonably.
Alan

MikeKanterakis
01-20-2005, 07:16 PM
ok, thanks for the recommendation. Have you done a write-up regarding the "better" quality of your rebuilt torque converters? If not, I think it would be a great idea.

Dirtyd0g
01-20-2005, 08:04 PM
ok, thanks for the recommendation. Have you done a write-up regarding the "better" quality of your rebuilt torque converters? If not, I think it would be a great idea.

I have done several writeups on tccoa about my 4r70w converters. I will be building a few of these aod converters here in a couple weeks and I'll get some pictures. Words mean nothing without pictures. :)
Alan

MikeKanterakis
01-21-2005, 01:11 AM
Wow, that made for some interesting reading. Would you answer a few questions for me?

1. What is/are single / tripple plates?
2. you recommended me a 2200 stall non-lockup converter. are any of the ones you will be building in a few weeks available for purchase?
3. How streetable are the TC's you build? Or is that just a matter of the stall?

Dirtyd0g
01-21-2005, 01:43 AM
Wow, that made for some interesting reading. Would you answer a few questions for me?

1. What is/are single / tripple plates?
2. you recommended me a 2200 stall non-lockup converter. are any of the ones you will be building in a few weeks available for purchase?
3. How streetable are the TC's you build? Or is that just a matter of the stall?

Single and triple plates refer to 4r70w transmissions. Aod transmissions do not have a lockup clutch.
All of the converters I build are for sale, see [email protected] performance
streetability is determined mostly by stall speed. Yes the 2200 is completely streetable. You will need to run an external cooler to run the converter unlocked.
Alan

MikeKanterakis
01-21-2005, 03:41 AM
My brother gave me the one from his old auto tranny. it's a stacked plate design, and it's like 8 X 11 inches. I was thinking of attaching a 9'' fan to that with a temp. switch. Do you think the fan would be over kill?

Dirtyd0g
01-21-2005, 07:48 AM
You only need a fan if you mount it somewhere that doesn't get air

Randy N Connie
01-21-2005, 08:39 AM
I am running a 8.5'' convertor 2400 stall,non-lock.I had to install a
26000 GVW 10'' wide x 12'' long cooler.Still ran warm,so I install in
a series a 9'' wide x 13.5'' x3.5 thick cooler with a 10''fan with
160 degree thermostat.And the trans fuild runs though the radiator.

And my SC still runs warm when it is 32 degrees out.So I do not think the car
will be drivable in the summer.So I am going to delete the radiator as
part of the transmission cooling system.And hope that the motor and
trans will start running cooler.

And I lost over 4 miles per gallon of gas.This is with a stock motor.

I think I may have to pull the lentech trans out.And install a locking convertor.And I have a one peice shaft in the trans.So I need to
know what type convertor I can run now to cool the car down.
I don't think that a stock convertor will work now.I may need to get
another trans.This will be 5th trans in less than 6000 miles.

Randy

Randy

tim
01-21-2005, 09:13 AM
I got dibs on the lentech trans if you dont want it. Ever thought of a fuller 10 speed lots of gears and really heavy duty!!

Dirtyd0g
01-21-2005, 01:20 PM
I am running a 8.5'' convertor 2400 stall,non-lock.I had to install a
26000 GVW 10'' wide x 12'' long cooler.Still ran warm,so I install in
a series a 9'' wide x 13.5'' x3.5 thick cooler with a 10''fan with
160 degree thermostat.And the trans fuild runs though the radiator.

And my SC still runs warm when it is 32 degrees out.So I do not think the car
will be drivable in the summer.So I am going to delete the radiator as
part of the transmission cooling system.And hope that the motor and
trans will start running cooler.

And I lost over 4 miles per gallon of gas.This is with a stock motor.

I think I may have to pull the lentech trans out.And install a locking convertor.And I have a one peice shaft in the trans.So I need to
know what type convertor I can run now to cool the car down.
I don't think that a stock convertor will work now.I may need to get
another trans.This will be 5th trans in less than 6000 miles.

Randy

Randy


It isn't the lack of lockup killing your gas mileage and creating all that heat. Your converter is too small for street operation. I have actually had customers tell me they got better gas mileage by installing a 2000 stall non lockup converter. Any non lockup will generate slightly more heat ,but one that small will generate too much. Small converters like that are generally race only. Anything less than 10 inch without lockup is too small for the street.
Alan

Randy N Connie
01-21-2005, 02:24 PM
I made a mistake my convertor is 9.5''

Randy

MikeKanterakis
01-26-2005, 03:25 PM
Hey dirtyd0g, if you have the time, could you write a post explaining the workings of torque converters? It would make for some great reading.

Dirtyd0g
01-26-2005, 06:27 PM
Hey dirtyd0g, if you have the time, could you write a post explaining the workings of torque converters? It would make for some great reading.

You can feel free to search my posts on TCCOA. I have done alot of threads there. Search the drivetrain forum because anything else is probably just me rambling. Start here this thread explains alot.
http://forums.tccoa.com/showthread.php?t=47149

tim
01-27-2005, 10:45 AM
Randy thats to bad, I wonder if the converter in my car would work in yours? I would really like a 9.5 for drag racing. I dont think it will cause you have a soild input shaft.

Randy N Connie
01-27-2005, 11:08 AM
I think I have not been plain enough about my thoughts of a AOD.
My AOD & convertor is near perfect.

Its just a automatic trans do's not fit my driving style.

Why do you think it is, that most all racers, in all forms of racing
around the world do not use automatic transmissions? Its the same
reasons that I would rather not use them.

Thanks Randy

MIKE 38sc
01-27-2005, 11:46 AM
I know what you mean Randy. I myself left auto trannys back in the early 80's and could'nt have been happier. Then I got the SC and thought I'd give em a try again, however if it all fails I will be converting to a manual myself and it will not be the Mazda tranny either.
Alan is building me a converter that I think will be just what the Dr. ordered.
Alan is pretty damn sharp and very honest to boot! That 1 in a 1,000,000 find! ;)

tim
01-27-2005, 01:15 PM
Randy to bad you want a stick. The setup you have is the dream tramsmission/ converter combo. From what I understand it will hold up to almost anything. I like an automatic. First i have to shift all day so a stick really has no appeal to me. Next I really dont like the trans that was used in the S.C. I dont know what else you could use. A lentech full manual with all the tought stuff and a 9 inch converter would be my dream trans. It cost more than my car is worth. I am taking my car out to dirtydog and have him set me up a converter to match my combo. I think it will really wake it up on the bottom end. Then if it will work with it I will change out the 3:73 rearend for a 4:10. All drag race is what I want with a tad of street driving. Now all I have to do is wait for the weather to break. I am not going to drive it on snow and salt. It has a perfect body and I plan on keeping it that way.

Dirtyd0g
01-27-2005, 01:24 PM
I think I have not been plain enough about my thoughts of a AOD.
My AOD & convertor is near perfect.

Its just a automatic trans do's not fit my driving style.

Why do you think it is, that most all racers, in all forms of racing
around the world do not use automatic transmissions? Its the same
reasons that I would rather not use them.

Thanks Randy

Alot of drag racers still use powerglide transmissions. Auto's are more consistant for drag racing.

Randy N Connie
01-27-2005, 02:00 PM
But I am retired from Drag Dacing 1968 TO 1996.And power glides are chevy parts. :)

When I drag raced we used multi stage slipper head clutch with no trans.in pro-fuel class.Top fuel we use BM 2 to 3 speed.

RANDY

MIKE 38sc
01-27-2005, 02:10 PM
Alan Randy wants to do some road racing and likes the extra control that a manual gives you in those instances, such as engine breaking and setting up for turns. True he loves to drag race as well but he really has a hankering for some twisties.
Couple that with the fact that the man has had undoubtedly the worse luck with AOD's I've ever heard of(gone through about 5 of them it seems) and I can see why he has a bitter taste in his mouth for them.
The biggest problem with auto tranny's seems to be the mystery that surrounds them, so everybody is left having to trust some tranny guy to help them with there problems. The next biggest problem seems to be that about 99% of those tranny experts just bend everybody over for the fast buck simply because noone can tell what they've done or not done to there tranny.
I admit that once you first started coming here I did'nt give it much thought because so many experts have come and gone.
I spotted a thread you were posting in one day where you posted a link to a thread you posted at the TCCOA so I checked it out. My first thought after reading that thread was WOW!!! I've read some more of your threads since then and all I can say is I hope you stay here. I enjoy and appreciate your honesty and willingness to show everyone just what the so called experts are getting away with. You've provided a much needed and long overdue breath of fresh air on the subject of auto tranny's, so I really hope you stay around and help us to learn some much needed things about these mysterious machines. You're gonna meet up with some skeptasism for a little while but thats just because we've all been sold a pig in a poke from the guru's and were not so easy to give our trust anylonger.
I'm certainly no expert on these tranny's but I've learned enough about them through the years to know that every single one of the so called big boys is raping there customers for the services they provide. Come on over $2,000 for a rebuilt tranny? give me a break! Unless they hand machine every single part in that tranny from billet I just do not see it. Your threads where you've torn down some of these experts tranny's and cut apart there CONVERTERS to show whats actually been done with pictures is just fantastic. From what I've seen you hide nothing regardless of what the big name builder did and you're able to explain why something is good or bad. I commend you for this because I certainly appreciate it.

Randy N Connie
01-27-2005, 02:18 PM
Mike thank for writing that.I feel the same .I am glad Alan is posting here on the SCCoA.

Alan SORRY if I come OFF sounding negitive.It is in no way pointed toward you.

RANDY

joenintiesc
01-27-2005, 02:21 PM
Yes, I completely concur with everything Mike said above. It's good to have such a knowledgeable person take the time to share thier expertise with others so willingly! I bought a TC from Alan recently and cannot wait to get it installed, but the whole tc/transmission to engine relationship is still mostly mystifying to me. I read all Alan's posts on the subject here, and my only request to him would be to see if maybe he's be willing to do a little comprehensive write-up on the whole tc subject as it pertains to the SC for the FAQ section? I'm sure it would be read by everyone! :)

Dirtyd0g
01-27-2005, 06:27 PM
I am waiting on parts and I am going to build some of those converters. When i do I will get lots of pictures. Is there a place to upload them here?

MikeKanterakis
01-27-2005, 10:47 PM
Dirtyd0g, thanks for the heads up regarding your previous posts on TCCOA. I've read them and all I can say, is " I'm hungry for more information". Have you done any writing on the Torque Converter for the AOD? I was told today that the AOD doesn't have any friction material in the TC.??? Is that true? if so, how does "lock-up" or "direct-drive" happen in the AOD? (it's locks up in 3rd gear right?)

btw, i've started my first AOD rebuild. :D

Dirtyd0g
01-28-2005, 12:39 AM
Dirtyd0g, thanks for the heads up regarding your previous posts on TCCOA. I've read them and all I can say, is " I'm hungry for more information". Have you done any writing on the Torque Converter for the AOD? I was told today that the AOD doesn't have any friction material in the TC.??? Is that true? if so, how does "lock-up" or "direct-drive" happen in the AOD? (it's locks up in 3rd gear right?)

btw, i've started my first AOD rebuild. :D

I haven't done any write ups on the aod's yet. They do use most of the same parts. The only difference is the spline and front cover. The rest is the same.
These have 2 inout shafts. Take the small input shaft and put it into a stock converter. It will not turn without turning the entire converter. The larger spline will.

MikeKanterakis
01-28-2005, 09:44 PM
oh, ok, I guess the cheap TC I got from autozone either didn't replace the friction material or used cheap material. Oh well, it's for my wife's car, so since she isn't going to be racing it, all's well. They said it had a 1600 stall. well, hope to see the improvement in fuel economy.

brw, aod is completely torn down. I'm gonna atack the sub-assemblies next, and have the case jetwashed tomorow. I'll probably have the local trans place take out the bushing in the rear of the case and press in a new one. Other than that, the tear down went nice and smooth. (so far)...

Dirtyd0g
01-28-2005, 11:39 PM
oh, ok, I guess the cheap TC I got from autozone either didn't replace the friction material or used cheap material. Oh well, it's for my wife's car, so since she isn't going to be racing it, all's well. They said it had a 1600 stall. well, hope to see the improvement in fuel economy.

brw, aod is completely torn down. I'm gonna atack the sub-assemblies next, and have the case jetwashed tomorow. I'll probably have the local trans place take out the bushing in the rear of the case and press in a new one. Other than that, the tear down went nice and smooth. (so far)...

There is no friction inside an aod converter. They are actually very cheap to build if you just clean them out and put them back together. The expense comes from replacing all of the splines with hardened ones, deleting lockup, and massive time spent reinforcing the fins. Building stock units properly requires removing the direct drive damper to clean underneath it ,but very few people do that because it is alot of work. By the time you take it out you're best to just delete it and go non lockup. Also installing bearing in place of the stock plastic substanically drives up cost. For what it is worth stock replacements sell all day long for about $125
Alan

MikeKanterakis
01-29-2005, 01:34 AM
Sweet!!! I paid $75.00

MIKE 38sc
01-29-2005, 02:01 AM
Sweet!!! I paid $75.00

Now that screams qaulity! :p Possably another fine Chinese import? :p

MikeKanterakis
01-29-2005, 02:12 AM
Well, the box it came in said Accurate Transmissions and had a website, www.accuratetrans.com (http://www.accuratetrans.com/)

MIKE 38sc
01-29-2005, 02:24 AM
Just teasing you Mike! :)

MikeKanterakis
01-29-2005, 02:40 AM
Yeah, it's cool, I felt like a goofball ordering my torque converter from autozone anyways.

tim
01-29-2005, 04:26 AM
Well if its for your wifes car you did ok. My next door neighbor works for that company. They are right down the street from me. They sell a lot of transmissions and torque converters so they cant be to bad. $75 is a good price, saving money is a good thing.