radz282003

iTrader: (1)

Good day all.

Well, it' s just as the question above. How much RWHP do you guys loose, with the converter unlocked? I have a SS3800, and unlocked, it put down 317 RWHP and about 310 RWTQ. With it locked, it put down 354 RWHP and 360 RWTQ. The dyno tuner advised he usually doesn' t see this much of a difference, but, I know my car is finicky. I FINALLY got a GOOD tune from this gentleman and I just wondered what you all had experienced.

Thanks - Chuck

Ragtop 99

iTrader: (7)

If unlocked was your first pull, pre-tuning, and you are comparing to a locked run with finished tune, then the tune could account for some of the difference.

If that was back to back (unlocked and locked) dyno after the tune was done, that's 10% and it is waaay too much loss. If this is the case, I'd call Yank to discuss the situation.

I would have expected 15 - 20 rwhp loss. My YTP converter lost 13 out of 380, but it is a very loose, but efficent design.

radz282003

iTrader: (1)

My understanding WAS they were back-to-back pulls, after tuning. I' ll have to look at the sheets tonight, but, I know I had seen a test, in GMHTP, of a Procharged TA, where they tested locked and unlocked, and the difference was like 40 horse'. Of course, that car was making 100+ HP, so, that' s that.

If anyone has more input, I would appreciate it.

Thanks again. Chuck

darrensls1

My car was 300 rwhp unlocked through a TCI 3500. I was told it was dangerous to dyno my car unlocked and that I would have to sign a waiver before they would do it. So needless to say, I never had it dynoed locked. But based on my 109 trap speed, I would say I'm around 330 rwhp locked.

So my educated guess is that I'm losing 30 rwhp between locked and unlocked on a 3500 stall with a 2.5 str. Remember too that the higher the STR the more HP your stall eats. Since you're making a little more power then me and probably have the same STR I'd say 37 rwhp (354 minus 317) doesn't sound that abnormal.

C5XTASY

What is the loss on a stock stall? Does anyone know? Thanks!
Ed

Ragtop 99

iTrader: (7)

Actually that only holds up when taking an existing converter and trying to increase its STR. Yank went through and tested their converters (along with some competing models) and 2 of their high STR units ate less HP most of the lower STR units. Within a given design however, increasing the stall speed, which increases the STR, generally resulted in lower efficency. My point is that it comes down to the design and it is not possible to generallize that all low STR converters are more efficent than high STR converters.

Roarin_8

iTrader: (5)

Don't know about how much HP it ate but with the converter locked I dynoed 313rwhp and 331rwtq and gained 2mph at the track.

radz282003

iTrader: (1)

Thanks for everyone's input. I appreciate it, and feel a little better.

jimbob

iTrader: (4)

Here's another one for you...

My old combo was 401 locked(SAE)......370 unlocked(SAE)....

Yank...(2800) stalling at over 4000...My fault not Yanks, to much Torque. Sold verter went with tighter Yank

Over 30 rwhp at that hp level is a little excessive. I think mine should have been in the 20ish range just for a comparison....I switched verters because of excessive loss....

rufretic

iTrader: (37)

I would take to the track and see how it performs before you start to worry about dyno numbers. If it doesn't do well then you can start narrowing down what might be the problem.

jimbob

iTrader: (4)

I like that answer best....

Although it is odd.......

Ragtop 99

iTrader: (7)

As long as he has something to baseline his mph against. I've seen stalls that eat lots of HP produce a good 60' and decent ET. However, the loss of HP results in a slightly slower ET and being down some mph. Ideally the SS3600 should give both a good 60' and a good mph. It should be pretty efficent.

Roarin_8

iTrader: (5)

Yeah my old mph with the stock converter was 106, now I managed to get a 108.

rufretic

iTrader: (37)

Yeah, I've been down that road. My first converter was a vig 3800, 1.7 60' 12.2 @ only 109. Now I have a yank ss4000, 1.6 60' 11.9 at 114. Very close 60' times and normal gains in et for the better 60' but I also picked up 5mph which I thought was huge.

Roarin_8

iTrader: (5)

5 mph is huge in a quarter of a mile, imagine half a mile

C5XTASY

Anyon know how the Yank SS3200 stacks up in efficiency versus the stock converter?
Ed

rufretic

iTrader: (37)

The ss3200 should be very efficient, even more so than stock.

BlackHawk T/A

iTrader: (3)

Wow so do Yank's generally perform better than the Vigilantes? A lot of people recommend the Vig...

Scotty-Z

iTrader: (5)

Who cares how much you lose? Think about how much horsepower that converter is simulating when you go to the track and lose .5-.7 off your times!

radz282003

iTrader: (1)

Yeah, I hear ya' there. The dyno operator mentioned how HE thought it seemed a little high, of a loss. I don' t know how many he has dyno' d ( with this conveter ) but I just thought I' d get some input. Honestly, I haven' t really optimized my setup with DRs yet, so I can' t say I have " lost " anything. Just curious.

I had been a LITTLE worried, because I just got it tuned Monday, and finally ran it Wedneday. With rolling into the throttle, until about the 60' mark, then putting it to the wood, AND banging' into the rev' limiter a few times going into third, my traps are about where they were last year, at the same time. Before I was running at about 107.XX, about this time last year. I' m sure if I got some DRs I could nail it off the line and pull out some better traps after I adjust my shift points. I didn' t add a stall until March and just installed the LTs, so I was pretty sure I should get about the same trap, but I noticed some of you actually gained a few MPH after a stall. I need some good tires to reep the benefits of what I have done, I guess.

Thanks again, for erveryone' s input.