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Conveter RPM calculations

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hrmmm I disagree

Turbo dave quote

REMAN D5
unlocked in the middle of 2nd gear yielded 55%
unlocked in 3rd at 80mph yielded 85%
unlocked in 3rd at 90mph yielded 90%
unlocked in 3rd at 100mph yielded 94%

locked in 3rd at 80mph yielded 93% ***
locked in 3rd at 90mph yielded 98% ***
locked in 3rd at 100mph yielded 100%

Now for the VIGILANTE. (These readings are at the end of it's second season of racing) (Always locked at WOT and about 80mph) (a couple seconds after the 2-3 shift)

unlocked in the middle of 2nd gear yielded 50%
locked in 3rd at 85mph yielded 97.3% ***
locked in 3rd at 95mph yielded 97.6% ***
locked in 3rd at 105mph yielded 97.7% ***
(the 10ths of percent differences could be attributed to measurement errors).

I did find some early Vigilante runs and it was rock solid at 99.7-100% through the above 3 parameters
--------------------------------------------------------------------------------
My reply.... ( due to Mr Computer genius here, I have more trouble with these quotes and crap!!))

( I put *** next to what I found odd)

The first thing that caught my eye was,the ***"s I dont care what RPM and Gear and speed your at, locked, the converter should be 100%. If it is not, trans is slipping. PERIOD! With that in mind how much percentage of slip does a manual trans have? With the clutch out it would be zero ? correct? Well a locked converter should be the same. AND not to take sides but if the trans is in fourth locked it will show over one hundred percent because the gear ratio will show more out than in.OD is about 30% , over. Now if I got this right, with the D-5, you say at WOT in 2nd gear it has 45% slip? With either converter I find this not possible. No way. It has to be more effiecent than that. With your Vigilante I might agree but with a D5 stall would have to be 4000-5000 to get that number. It would be REAL REAL ugly..Heat would be through the roof! And at load it best be a whole lot better than that (45%) or car is gonna be real high stall or rpm'ing big time and car not moving along well
REMEMBER!!!
A trans puts out only what is put in. RPM is the factor. Speed has nothing to do with INPUT speed. Once converter is locked, 100% has to be achieved unless trans is slipping or converter is slipping. Think about it. .The D-5 shows exactly how effiecent they are throughout the power band. The 9X11 converter is alot the same in this aspect. EVERY single Vigilante converter I have ever seen was always too loose for whatever application it has been in. ALWAYS loose. great for all out drag racing but sucks for everyday driving.
Just my thoughts...

Prove me wrong Dave....
What scares me is you just might :D:D:D

BTW ..... How are you out in the middle these days? I will always resent you for leaving this God foresakken state and NOT taking me with you!!!! You are an evil, evil person for this.....:D:D ROFLMAO


Bruce
WE4

And..... will you two knock it off... both of you.... LOLOLOLOL:)
 
Re: hrmmm I disagree

Originally posted by WE4

Prove me wrong Dave....
What scares me is you just might :D:D:D

BTW ..... How are you out in the middle these days? I will always resent you for leaving this God foresakken state and NOT taking me with you!!!! You are an evil, evil person for this.....:D:D ROFLMAO


Bruce
WE4

And..... will you two knock it off... both of you.... LOLOLOLOL:)

Can't prove anything right or wrong, I don't profess to know much about what's going on with the numbers. I just applied that formula (mph*47)/rpm to the numbers I took off my DS recordings over the last couple years.

Frankly, I was a little bit amazed at the why the Vigilante didn't show 100% either. I suppose it's possible the tranny could be slipping, but with your expertise coupled with that of Don Wang, I didn't even think about it. Between the two of you I've got to have one of the best tranny's in the country.
BTW, I lost your challenge. I have not been able to bust any of your parts, and the tranny's been going strong for... what, 2 years now? :D

The tranny still hits hard in every gear, and of course so does the TC when it locks. Don't know.... one of them may have some slip

My D5, I'm pretty sure had some slip in it. You could see it sorta "slidding" into lockup on DS. Took well over a second to "couple" and then only dropped the rpm by about 150-200.

Things aren't too bad out here. No employment to speak of, but we'll get by. My biggest problem is there's nobody anywhere close that I'd trust do any machine work on getting my "numbers matching" block back together. :mad:

Later Dude

P.S. NO MORE SMOG INSPECTIONS... neener, neener, neener ;)
 
thinkin again....

I know this is hard to believe, but I was thinking..... What about tire spin? In second gear that may apply and be a cause of the numbers being odd down low , or what we assume to be low.When that happens it does unload a bit then loads again when traction is achieved. Look at when tires recover in a burn out, as they pull down so does rpm. Also, I wonder if it is based on a 1 to 1 theory, meaning is low gear ratio( 274) and 2nd gear ratio (152)and 4th od (.67) even considered in the formula? If the clutch was slipping, I would think it would get worse towards the top. That is my understanding, more power to drive thru the clutch and at weight in high gear is where I believe you would see it.

Quote by turbo Dave

"I suppose it's possible the tranny could be slipping, but with your expertise coupled with that of Don Wang, I didn't even think about it. Between the two of you I've got to have one of the best tranny's in the country.
BTW, I lost your challenge. I have not been able to bust any of your parts, and the tranny's been going strong for... what, 2 years now? "

Yea, I would tend to lean that trans isn't slipping..... Converter could be tho...but still I doubt it. Good point BTW! ROFL :D

As for your parts "test", I can assume they passed eh? You were one who had "first hand" experiance..LOL

Are you a believer now, Dave? Hehe

Anyway, just thoughts

Bruce
WE4
 
I don't think I was suffering from tire spin. Could be, but I doubt it. I was running 11.5" ET Streets.

Couple of observations:
I see what you mean about different gear ratios in the equation though. Maybe taking readings in second gear don't work. Most of the ones I took were in 3rd gear (Drive) 1:1. And I never use O/D at the track so that's not a concern.

I'm wondering where the loss of 3% might be coming from on this vigilante?? It's a -6 pump multi disk and really isn't very loose. I don't think anyway.
I did a brake stall test the other day, and here's the results:
0# boost stalled to 2400
5# boost stalled to 2800
10# boost stalled to 3200
15# boost stalled to 3700

seems consitent with boost rise. Any thoughts?
Maybe the 3% is being lost in the tranny, but it sure "feels" healthy, but does have a solid two years of racing under it's belt.

I think I was a believer before your parts went in. When I looked at them when they were delivered, it only took one look at that input shaft on the intermediate drum to know I probably wouldn't be breaking that part any longer!! I even flogged on it for a few months with that stage right tranny brake I used to have in there (removed about a month after install).
 
If you did this test standing still

Turbo Dave quote
"I did a brake stall test the other day, and here's the results:
0# boost stalled to 2400
5# boost stalled to 2800
10# boost stalled to 3200
15# boost stalled to 3700 "


If you did this test standing still, that converter is loose. Did you ever hit the point in which it drove through? Ill bet if you put a brake on it and took it as high as you could it would go 42-4500.
As far as the loss locked, man that is the tough one. But I would still bet it is looser than you think. Not an arguement, just an observation. Good sloid info tho. :)

And....I just noticed this is with a t44? Man that is loose.....


Bruce
WE4
 
Re: If you did this test standing still

Originally posted by WE4
Turbo Dave quote
"I did a brake stall test the other day, and here's the results:
0# boost stalled to 2400
5# boost stalled to 2800
10# boost stalled to 3200
15# boost stalled to 3700 "


If you did this test standing still, that converter is loose. Did you ever hit the point in which it drove through? Ill bet if you put a brake on it and took it as high as you could it would go 42-4500.
As far as the loss locked, man that is the tough one. But I would still bet it is looser than you think. Not an arguement, just an observation. Good sloid info tho. :)

And....I just noticed this is with a t44? Man that is loose.....


Bruce
WE4


See, now that's just what I mean. I don't know as much as I like to think. I thought it was a little tight. At 15# of boost the car is just barely trying to move. I can hold it, but I'm on the brakes real hard. It was a -0 pump that I had re-stalled because I wanted to be able to build more boost on the line without pushing through the lights, and this seemed the only option at the time.
I tried a stage right brake, but hated that thing and took it out and pitched it. Couldn't afford a real brake so I went back to foot braking and a higher stall.

I'm sure you're right, If I had a "brake" it would probably easilly stall to well over 4500 just by the "feel" of it. Those crappy 16" ET Streets I was running though would never bite with more than 12-15# unless the track was "super" prepped.

In defense of my 44 though, I am running a .85 housing. So my whole setup could have been a lot easier, had I had the $$ for good slicks and the wheels to mount them on, and a good BatBrake. Then the -0 pump would have been ideal.

I get such an adrenalin rush when that converter clutch/s hit a couple seconds after the 2-3 shift! AND my intermediate shaft don't snap ;)
 
Now you did it... You got me thinking again....

You know.... might be a good test bed since you got so much info. Going into winter there tho soon eh? Someday, when you can, call me and maybe we will try something, for no other reason than just to learn some more. Might be fun and informative. Personally , I feel that if a combo is covertered correctly, a brake isn't needed in 95 % of the cases, and I make the brake. (Not real good for sales you know , lol) In fact, I know I talk more out of than we sell. Hrmmmm.... Another challange.... Are we having fun yet, Dave? :D
ROFL

Bruce
WE4
 
Who me??? I'm always having fun!!
After all, I haven't busted the tranny in over two years.

Feels almost like winter's already trying to get here :( Never got over 60 today, and wont for another 7 days at least.

Went from running the A/C one day to almost having to light off the furnace the next. :confused:

Used to be an "every six month" ordeal. :mad:
 
Vigilante intalled and ran this Saturday at the M7 event. I ran through just above 6000 RPM at 134.5 My old convertor slippage was 12% and was about 6200 at 128.5, but there is a margin of error because I cannot monitor VSS at RPM so who really knows exactley what RPM you are at when you trigger the lights. The new one is at about 6% and I netted another 6 MPH with it. In conclusion, there is a lot to be gained with a properly matched convertor. Just because one works doesn't mean you are getting all you can through it. I spent $650.00 and got 6 MPH and will get a good .2 when I re-learn how to drive the car. I am having to launch with lower boost now. I am by no means a "expert" on convertors, but I did learn what to watch for, and diagnose problems. :)
 
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