1/8 mile trap rpm 6622
4:88 gears
Powerglide
14-32 slick
2850 pounds.
4:88 gears
Powerglide
14-32 slick
2850 pounds.
73 Duster build named Fred
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dusterbing the peace
FABO pyrite member
Roughly 14% converter slip across the stripe.
Mine was 12%.
We both had roughly 1200 rpm on the shift drop, the second shift on the data log I grabbed happened to be a little short.
Ok, now I am a little baffled. I still think I can benefit from more stall on the launch but the shift drop has me thinking....
If you didn't have at least 1000 rpm shift drop what would be the point of shifting.
You might need more rear gear.
You might need more rear gear.
dusterbing the peace
FABO pyrite member
No, just 904. 10-15% is great for track, terrible for street. Converter Slip = torque multiplication (to the approximate range listed above…too much and it’s just a bad selection). Also, slip = heat of course.
I should of course add that this is for the bracket racing we’re doing here. Soggy converters help with consistency because they really narrow your operating band which leaves less room for error. If you had to drag the engine from 3500-7000 in every gear your times would be all over the place!
All out racing and high HP stuff will favor less slip or lock-up’s to maximize MPH and minimize ET.
Some of the reasons why telling the converter folks what your combo is and what you actually want out of it are so important.
My son went from 4:30
To 4:10
With the converter he’s going to try and I thought it would hurt and it didn’t. And he’s 300 pound heavier, 48 inches small engine, .040 less cam lift.
dusterbing the peace
FABO pyrite member
Looking at your dyno print, I would agree that you want some more RPM to get off the line. And it’ll certainly raise the RPM on the shift to get it there, but they may have to find a bit of a balance. Just make sure to give them all the info they’re asking for (weight, gear, tire dia, tell them you have a dyno graph and send it to them, they may still ask for engine combo for reference).
I gave them all the info when I initially ordered it and I went over what it is doing on the track. Kenny said he knew what to do to get it to perform the way I want. I am going to try the loner converter which should stall 400-600 more than the one I currently have. I will be able to see immediately if my theory is correct or at least if I am heading in the right direction. It should also tell me if I want more stall or not.
I've said this numerous times now and I will say it again. I am trying to get my car to leave harder than it does currently. I am assuming this is what I need to get my 60' times down, which in turn will give me more out the back end and a lower ET. Based on all of the information I have (which I have openly shared on this forum), I feel my converter is stalling well below the peak torque rpm and I am giving away a bit off the hit.
I will try this first before sending out my converter.
Do you know what I really like about this. 8 years ago a 10.50 small block was kick azz fast. Now if we run 10.50’s we are bending over backwards to “fix it”. Lol
You're right about that. In this case though, I am trying to fix one thing and that is how the car leaves. I think if I fix that, I'll get the benefit of the car being quicker.... lol
73smallblock
Well-Known Member
60' is as you stated, is going to pick up e.t. on the big end. The converter that's in my car at one point and time the converter that is currently in my car, would only go 1.52 60'. Even after changing from speedmaster's to trickflows, it went 1.48 once and I think that's when it broke, my e.t. didn't really move much. Once I got a different converter and my 60' went into the 1.4s my my e.t. changed almost .4 in the 1/8. The only reason I switched converter's after that was because 1. I wanted a spare. 2. I wanted to see what a converter "built" for my combo would pick me up even more. Turns out that the one I had built, works exactly as the one I took out, lol.
dusterbing the peace
FABO pyrite member
Not sure if I miscommunicated, will try to add clarity:
Sometimes they miss. I’m betting he’ll get it right with even more info this time around.
Still in agreement here!
Yep, and as you said later, getting closer to your peak torque is the path.
Should contribute to better ET, but the added slip may bring the MPH down a little. Less ET = less time on track = less time for errors, so I agree with this yet again.
Pretty awesome you can try before you buy!
I agree 100%. In fact, that's probably why so many converter companies give you a free re-stall.... lol
I think we all agree that every car is different, even when they have pretty much the same parts. They can only make an educated guess as to what you need. At least now, they know what they built only flashed 5000 and if it is 5800 that we want, they will know what changes to make to get it much closer.
Maybe I’ll throw a curveball and throw on my 28” tall drag radials. If they hookup, the added gear will definitely wake up the launch. lol
dusterbing the peace
FABO pyrite member
They should stall a little higher when they hook…hook and book!!!
You just don't want to buy me a steak lol
Are your 29.5s 30.60 height?
No, my 29’s are 29.2…. lol
Ok, time for an update….
Let me start off with thanking everyone for taking the time to try and help me figure out why my car was leaving so soft. Special thanks to @73smallblock for loaning me his spare converter and to @71Demon528 for taking the time to talk about my theory and for agreeing with me.
I felt all along that my converter wasn’t performing the way it should and that it was holding back the performance. Starting with the first time I dynoed the car, then to the track in Vegas, then the dyno again and finally the 2nd time in the track here, I thought there was something going on with the converter. The car just felt like I was driving a stick shift car with a slipping clutch.
Got the spare converter which is a 5300 stall (2600-3200 lb car with 360) Turbo Action on Friday after work and I proceeded to get to work. Pulled the trans and converter, then called it a night. Got up this morning and got the converter in and trans mated to the engine and stopped to go watch my grandson’s football game. He scored 2 touchdowns and a 2 point conversion and they won their game 24 - 8. Headed home to finish getting the car back together. Decided to check valve lash whilei I had the hood off and a couple of hours later with the trans fluid topped off, the car was back on the ground and ready for a test drive.
Backing up out of the shop, I immediately noticed a difference in the converter. Before, you could tell I had a 5000+ stall converter because it took a lot of throttle to get the car moving. Now it seemed to take very little to get going. At first I was concerned that the converter would be too tight and stall end up lower than the one I pulled out. By the time I drove around the block to the spot I use to test hits, I had convinced myself that this is what current converter technology was supposed to feel like and when I finally got after it and saw the converter flash at between 5400-5500, I immediately felt what the car had been lacking all along. This sumbeech gets up and moves now!
I stopped and launched the car again and witnessed a solid 5500 rpm flash again…. Hell yeah!
I’m not going to be able to sleep for 6 days now waiting to make the trip to @MOPARMAGA and @Newbomb Turk ’s home town for their Summit Racing series opener next weekend. I fully expect to see some new PB’s and finally get to experience what I built this car for. I should also be able to decide on how much more converter I will want when sending the PTC in. I might even choose to go with turbo action on the next build…. I guess we will see.
Let me start off with thanking everyone for taking the time to try and help me figure out why my car was leaving so soft. Special thanks to @73smallblock for loaning me his spare converter and to @71Demon528 for taking the time to talk about my theory and for agreeing with me.
I felt all along that my converter wasn’t performing the way it should and that it was holding back the performance. Starting with the first time I dynoed the car, then to the track in Vegas, then the dyno again and finally the 2nd time in the track here, I thought there was something going on with the converter. The car just felt like I was driving a stick shift car with a slipping clutch.
Got the spare converter which is a 5300 stall (2600-3200 lb car with 360) Turbo Action on Friday after work and I proceeded to get to work. Pulled the trans and converter, then called it a night. Got up this morning and got the converter in and trans mated to the engine and stopped to go watch my grandson’s football game. He scored 2 touchdowns and a 2 point conversion and they won their game 24 - 8. Headed home to finish getting the car back together. Decided to check valve lash whilei I had the hood off and a couple of hours later with the trans fluid topped off, the car was back on the ground and ready for a test drive.
Backing up out of the shop, I immediately noticed a difference in the converter. Before, you could tell I had a 5000+ stall converter because it took a lot of throttle to get the car moving. Now it seemed to take very little to get going. At first I was concerned that the converter would be too tight and stall end up lower than the one I pulled out. By the time I drove around the block to the spot I use to test hits, I had convinced myself that this is what current converter technology was supposed to feel like and when I finally got after it and saw the converter flash at between 5400-5500, I immediately felt what the car had been lacking all along. This sumbeech gets up and moves now!
I stopped and launched the car again and witnessed a solid 5500 rpm flash again…. Hell yeah!
I’m not going to be able to sleep for 6 days now waiting to make the trip to @MOPARMAGA and @Newbomb Turk ’s home town for their Summit Racing series opener next weekend. I fully expect to see some new PB’s and finally get to experience what I built this car for. I should also be able to decide on how much more converter I will want when sending the PTC in. I might even choose to go with turbo action on the next build…. I guess we will see.
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Glad you heading in the right direction buddy.
That's a great update. It will be nice to see you Bill. I'm glad you got a good idea of what you should have with the torque converter, good **** and good job !
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