Still missing 2 tenths???
#1256499
06/24/12 03:23 PM
06/24/12 03:23 PM
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Joined: Feb 2003
Posts: 1,730
Red Deer, Alberta
bill_greenwood
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Red Deer, Alberta
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To recap, I changed convertors 2 years ago leading me to pick up .05 on the 60', but lose 3 mph and .3 overall. With my first convertor and 4.88 gears, the car was routinely 11.35-11.40 at 118-119 mph. Trap rpm was 7200, which it would routinely hit well before the strip and simply keep climbing the torque convertor from 1100-1200' or so until the stripe.
When I changed the convertor (TCS 8") from approx. 4200 stall out to 4700, the car immediately picked up .05 in the 60', but I found it struggling to pull in high gear. Trap speed immediately dropped to 115-116 and only hitting 66-6700 in the lights. ET dropped back to 11.65-11.70.
As my old gear set was in really bad shape, and I now had 500 rpm to play with, I switched up to 5.13's in the hope of getting some of my ET back. Here's where things stand after a good weekend where we put 10 good passes on the car-
60'- 1.58
330'- 4.650
1/8- 7.291 @93.2
1000'- 9.60
1/4- 11.56 @ 114.02
I had a couple of little issues dog me, but over 10 passes, the car is definitely more consistent than it ever has been, but it's still hitting the rev limiter well before the stripe and then climbing the torque convertor (i.e it is still actually pulling). My puzzle is that it should have (IMO) came back to the 11.30's but hasn't.
One clue- it seems to recover "softly" on the shift. Any ideas?
Shifting at 6800, BTW.
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Re: Still missing 2 tenths???
[Re: bill_greenwood]
#1256500
06/24/12 05:09 PM
06/24/12 05:09 PM
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Joined: Jan 2004
Posts: 13,247
Mt. Vernon, Ohio
dartman366
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I Live Here
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several things come to mind,,fuel, are you running out? HP, now that the converter is locking up tighter is it actually causing the motor to need more to pull it thru,,torque, where is your torque band? and are you actually going way beyond it's peak effeciency? and by bumping the rev limiter it will make it consistent but won't let it rev beyond that, killing ET and MPH just like putting a govenor on it 
Light travels faster than the speed of sound,,,this is why some people seem bright untill you hear them speak.
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Re: Still missing 2 tenths???
[Re: bill_greenwood]
#1256501
06/24/12 05:59 PM
06/24/12 05:59 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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What rpm chip are you using that its hitting... I would pull that chip and make a pass without it... hitting the rev limiter is like throwing out a anchor 
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Re: Still missing 2 tenths???
[Re: bill_greenwood]
#1256502
06/24/12 06:13 PM
06/24/12 06:13 PM
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Joined: Nov 2009
Posts: 2,177
ill
dennismopar73
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Quote:
To recap, I changed convertors 2 years ago leading me to pick up .05 on the 60', but lose 3 mph and .3 overall. With my first convertor and 4.88 gears, the car was routinely 11.35-11.40 at 118-119 mph. Trap rpm was 7200, which it would routinely hit well before the strip and simply keep climbing the torque convertor from 1100-1200' or so until the stripe.
When I changed the convertor (TCS 8") from approx. 4200 stall out to 4700, the car immediately picked up .05 in the 60', but I found it struggling to pull in high gear. Trap speed immediately dropped to 115-116 and only hitting 66-6700 in the lights. ET dropped back to 11.65-11.70.
As my old gear set was in really bad shape, and I now had 500 rpm to play with, I switched up to 5.13's in the hope of getting some of my ET back. Here's where things stand after a good weekend where we put 10 good passes on the car-
60'- 1.58
330'- 4.650
1/8- 7.291 @93.2
1000'- 9.60
1/4- 11.56 @ 114.02
I had a couple of little issues dog me, but over 10 passes, the car is definitely more consistent than it ever has been, but it's still hitting the rev limiter well before the stripe and then climbing the torque convertor (i.e it is still actually pulling). My puzzle is that it should have (IMO) came back to the 11.30's but hasn't.
One clue- it seems to recover "softly" on the shift. Any ideas?
Shifting at 6800, BTW.
NEED MORE INFO,
but I'll take a wild guess from what I can read between the lines.
MUST BE SMALL BLOCK!
CAM SHAFT?? would be my question,
513 (weh!) size tire? 513 gears better have good camshaft!!
hitting rev limiter well before line??
My bet is your out of camshaft with the gear you have and tire size is guess @28-29 tire?? guess!! Difference between 488 and 513 not much @ 200-300 rpms at the finish thus the reason for the tighter vert(your old one you took out!) to run faster?
So it means your limiter set ? @7200?
with those combos, without limiter easy 7500 or more depending on loss out of the vert would be common!
just guessing!!
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Re: Still missing 2 tenths???
[Re: bill_greenwood]
#1256504
06/24/12 10:07 PM
06/24/12 10:07 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
Yes, small block. 360 @ .040 over. 5.13 gears and 9x30 tires- Hoosier drag radials. 528-286 MP solid, 1.6 rockers. Fuel situation is good. Holley 280 gph (black) pump and 1/2" lines to regulator. Pump will fill a gallon pail in 15 seconds after the regulator. Fuel pressure is 7.5-8 psi.
I will try bumping the rev limiter up 100 rpm at a time and see what that results in.
Max toque with the old dual plane intake was at 4400 and max hp with the dual (LD4B ported with milled divider) was at 6300. I now run a Weiand X-celerator and have moved up to a 750 Claw over the old 650 Demon. Jetting up didn't seem to make any difference when we tried that last weekend.
Were you hitting the rev limiter last weekend...
changing from a dual plane to a single plane is gonna
move the torque and hp higher
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Re: Still missing 2 tenths???
[Re: bill_greenwood]
#1256505
06/24/12 10:19 PM
06/24/12 10:19 PM
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Joined: Jan 2004
Posts: 13,247
Mt. Vernon, Ohio
dartman366
I Live Here
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I Live Here
Joined: Jan 2004
Posts: 13,247
Mt. Vernon, Ohio
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Quote:
Yes, small block. 360 @ .040 over. 5.13 gears and 9x30 tires- Hoosier drag radials. 528-286 MP solid, 1.6 rockers. Fuel situation is good. Holley 280 gph (black) pump and 1/2" lines to regulator. Pump will fill a gallon pail in 15 seconds after the regulator. Fuel pressure is 7.5-8 psi.
I will try bumping the rev limiter up 100 rpm at a time and see what that results in.
Max toque with the old dual plane intake was at 4400 and max hp with the dual (LD4B ported with milled divider) was at 6300. I now run a Weiand X-celerator and have moved up to a 750 Claw over the old 650 Demon. Jetting up didn't seem to make any difference when we tried that last weekend.
I have found that MSD's chip's can vary as much as 300 rpm, I just put a shift-noid in my car and had to use a 7000 chip to get it to shift at 6800. 
Light travels faster than the speed of sound,,,this is why some people seem bright untill you hear them speak.
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Re: Still missing 2 tenths???
[Re: bill_greenwood]
#1256506
06/24/12 10:22 PM
06/24/12 10:22 PM
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Joined: Nov 2009
Posts: 2,177
ill
dennismopar73
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Quote:
Yes, small block. 360 @ .040 over. 5.13 gears and 9x30 tires- Hoosier drag radials. 528-286 MP solid, 1.6 rockers. Fuel situation is good. Holley 280 gph (black) pump and 1/2" lines to regulator. Pump will fill a gallon pail in 15 seconds after the regulator. Fuel pressure is 7.5-8 psi.
I will try bumping the rev limiter up 100 rpm at a time and see what that results in.
Max toque with the old dual plane intake was at 4400 and max hp with the dual (LD4B ported with milled divider) was at 6300. I now run a Weiand X-celerator and have moved up to a 750 Claw over the old 650 Demon. Jetting up didn't seem to make any difference when we tried that last weekend.
Well, timing??@ set at what now? 38-40?
looks as tho you have some data from a dyno,
Max tq at 4400? would have thought higher than that??
6300 max hp??
something amiss here??
maybe still the cam , I'll look that cam up for what your trying to do and what I see is do-able..but the loss of et and mph after vert change, even with the 1.6 rockers
cam change to fit the rpms and vert maybe the future?? 
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Re: Still missing 2 tenths???
[Re: viperblue72]
#1256510
06/24/12 10:43 PM
06/24/12 10:43 PM
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Joined: Nov 2009
Posts: 2,177
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dennismopar73
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Quote:
Why not look at what you changed when your mph did? Your converter. May wanna put your old one back in and see if your mph goes back up. IF so maybe you bought a junk converter.
I would say yes he changed vert and lost,
the larger the stahl 4700 affected lockup capabilities of the new vert,
but he changed gears to get it back, thus more than likely over running the cam thus the loss. jmo
The right steps around his cam will and can make the car run even faster I believe ?
I don't like 110c/l cams (if that is what he has, and it appears he does) but to each their own I would have gotten a cam something in the 560-590 range @ 105 c/l installed @ 102 timing @ 34-38, shift @ 6500 6800 keep the 4700 vert , maybe even went with a 5200-5500 vert??
but still believe he can get close to the 10s what he has,
11.30 -40 car is no slouch his combo just a little off, you can tell by the just the change in the vert what happened!
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Re: Still missing 2 tenths???
[Re: dennismopar73]
#1256511
06/25/12 02:43 AM
06/25/12 02:43 AM
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Joined: Feb 2003
Posts: 1,730
Red Deer, Alberta
bill_greenwood
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Red Deer, Alberta
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Yes, that's the cam. While the dyno pulls were done with the old LD4B intake, I only ran that carb/intake for a little while. My best ever ET/MPH was with the Weiand/750 combo and the old convertor. I've just been perplexed by the gain in the 60' that has not shown up downtrack. That was a 11.28 @ 119.6 on a 1.66 60. My thought on the looser convertor was that I might find a tenth or better. The launch says it's there, but I've obviously upset the apple cart. I've been reluctant to be liberal with the rev limit, as I don't relish the idea of ruining my floor pan with my crank, which incidentally may be the most expensive cast 360 crank in the west (don't ask  ), but that's definitely a good place to start. Mr. Pbody- yes, I was hitting the rev limiter this past weekend. Something worth considering as well- I have moved the lash back from .024 on intake and exhaust to the recommended .028 & .032 just to see if that keeps the lifter breaking gremlins away. On the first day at the track this year, I broke two lifters- the pushrod punched through the insert on two of these Comp solids. I know tightening the lash made it quicker but a don`t recall the difference, and I`ve essentially assumed the single plane intake bumped the power/torque curve up about 500 rpm. Can't put the old convertor in as this is the old convertor with the stator angles changed. I really wish I hadn't tossed out my old time slips, too. They would make for some good comparison and probably have some clues.
Last edited by bill_greenwood; 06/25/12 02:48 AM.
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Re: Still missing 2 tenths???
[Re: bill_greenwood]
#1256514
06/26/12 08:57 AM
06/26/12 08:57 AM
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Joined: Nov 2009
Posts: 2,177
ill
dennismopar73
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Yes and No! you have such a gear it is rpm way over where it needs to be, the converter does help it get there faster, but the gears do too! When it comes to gears and convert it will always bring the finish line closer to the start, rpm wise, so any issues you have , say change gears, it makes any issues come on faster! You need to get the rpms down below that 7 grand mark, other wise that crank will not be there long! A 430 gear ,,maybe 456? that cam will work it not by far anything I would run , but you can get that combo to work, 112 c/l is something guys with power adders no20 may run ,? All of my cams come from Racer Brown, I have my c/l 105 installed at 102 advanced! You up against the chip with the 488, and the 513, because you don't want the crank to come out and see you,, so best thing is take gear away! you can do that, and put in low gear set in the trans, keep the vert you got in there,,IF it is working right? I have my doubts on that too. You have some what easy fix here, change gear first, change the chip up a little, go make couple hits with out it hitting the chip, shift the car lower in rpms??? may like what you see until change cams!?? 
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Re: Still missing 2 tenths???
[Re: bill_greenwood]
#1256515
06/26/12 11:11 AM
06/26/12 11:11 AM
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Joined: Mar 2007
Posts: 1,608
Rudolph, Ohio
moparguy7074
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Rudolph, Ohio
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What is the weight of your car? IMO, you have too much converter and gear. My engine combo is very similar, and I am running low 11.20's at 118, while shifting at 6400 and going thru the traps at 6400 also. My car weighs 2925 with me in it, and it has a 4.30 gear with 29x9 hoosier slicks with a 9" Turbo Action "J" converter. Oh yeah, my 60 ft. times are 1.51-1.55... 
Last edited by moparguy7074; 06/26/12 11:14 AM.
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Re: Still missing 2 tenths???
[Re: sshemi]
#1256516
06/26/12 11:14 AM
06/26/12 11:14 AM
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Joined: Oct 2008
Posts: 99
USA
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Quote:
Too much rpms everywhere
430 gear
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