How much ET will i pickup with following changes

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justinp61 said:
The car looks great Don.

It's raining here too, I was going to Bowling Green to the NMCA/NSS race tomorrow but there is a 80% chance of rain there. Hate to drive an hour and half to get rained on and not see any racing.
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Nice car. I`m wondering , did u ever stall the original set up ? I NOTICED U SAID U LEFT AT 2000 W/ IT. I WOULD ALMOST BET IT WOULD 60 FT BETTER , "if u have traction" , by jacking it up some. ----------as always disregard caps, cant seem to keep my fingers off it ! !
 
famous bob said:
Nice car. I`m wondering , did u ever stall the original set up ? I NOTICED U SAID U LEFT AT 2000 W/ IT. I WOULD ALMOST BET IT WOULD 60 FT BETTER , "if u have traction" , by jacking it up some. ----------as always disregard caps, cant seem to keep my fingers off it ! !
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It hooked all the time, no issues spinning. Car sits down over the tires because its minitubbed and has ladder bars. Yes, the convertor flashed at 4500.
I have tried leaving all over the place rpm wise. Doesnt effect how it 60 foots( and it shouldnt)
My old 9 sec Duster would 60 foot the same off idle or 2000 rpm off the foot, or 4400 using trans brake and two step.
I leave at 2k because its easier to look at the tach needle at 2000 for repeatability, keep it simple.
 
B3422w5 said:
It hooked all the time, no issues spinning. Car sits down over the tires because its minitubbed and has ladder bars. Yes, the convertor flashed at 4500.
I have tried leaving all over the place rpm wise. Doesnt effect how it 60 foots( and it shouldnt)
My old 9 sec Duster would 60 foot the same off idle or 2000 rpm off the foot, or 4400 using trans brake and two step.
I leave at 2k because its easier to look at the tach needle at 2000 for repeatability, keep it simple.
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interesting. A little story here, I first learned to use a new j model convertor in my hemi belvedere at St. louis one year. There was a 70 hemi barracuda in my class, I was about 4 thenths faster than him in all the time trials. Class elim. came around, he staged and stalled so high I COULD HEAR HIM, I was holding about 2500, we cut the same light, and he jumped out about 4 car lengths on me , I caught him at the finish line and thot I had beat him, but the win light came on in his lane. We ran the same identicle E T, and I was "4 full mph faster" than him , but he won !
 
Often “running up” on the converter on a good track will get you some 60ft..... funny, I’ve had a mild built 904 kicking around here for 20 years and I’m in the process of throwing it in the car. It’s trans brake prepped, A&A front clutch spring equipped, front drum lightened and cross drilled for fluid evacuation... We used to run it behind our high 10 iron head 360 which is still stacked in the corner :)
 
Finally gonna get out tomorrow night to test and tune. The Fri night test and tune wont have track prep due to a no prep race Saturday.
 
Wierd results tonight i am still trying to figure out. First a little background. Car typically used to run from mid 11.40’s to mid 11.50’s in summer air, depending on just how hot it was.
Mph typically in the 117’s in those summer conditions.
Last time out last year i was able to get the car in great fall air. Made 3 good hits that night. 11.36, 11.33, and an 11.26 to finish off the night( and season).... those passes were all right around 118 mph, the 11.26 was 118.40..............

Fast forward to tonight. Ditched the 727 and tight 4500 flash 8inch convertor for a 904 and much looser 5200 flash convertor..
Previous best ever 60 foot was a one time 1.587, came on that 11.26 pass. All other 60 foots ever were 1.61-1.63.
Tonight i got three good hits on the car, 60 foot on all three passes was 1.55 exactly, each time.
Previously i shifted the car about 6000/6100. Tonight with more convertor i bumped it up to 6500, to keep it out of the convertor on gear changes as much as possible.

Here is the wierd part. First pass car went 11.40. Mph was 113 and change. All the mph loss was in the back half of the track. Buddy thought my new mufflers might be the culprit. Took them off, next pass 11.39 at 114 mph...... wasnt the mufflers. Staged the car identical to how i always have, bring it up to 2 k and bump into the beam.
My brother talked me into making another pass, i really wasnt in the mood at this point, but i said OK.
Figured might as well try something different, so i brought it up to 3k and bumped in.... 11.37 at 117...... mph all the sudden is almost “ normal”.
So looks like the car is probably about a tenth and a half better taking same conditions to same conditions into account, picked up about 6 in the 60 foot, same conditions to same conditions........ and sucked big time in high gear, mph was definately off from what the car has done in the past

Dont know what to make of these results..... is the convertor too loose???

What happened to my mph.... car had never run slower than 116 something no matter how hot or bad of conditions, and tonight wasnt terrible, just typical summer evening in Mi.
 
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Just talked to a buddy of mine who is way sharper than me. Thinks this used tranny i bought on here is slipping going into high gear. Need to adjust the bands and try again.
Car was identical to the 60 foot and to the 1/8 mile last night. And the 1/8 mile MPH on all the passes was nearly identical. All just over 94 mph, all 7.20 or 7.21.
 
Don, how did it feel onthe gear changes? When I killed one of my converters it felt like it slid into gear. I could hear and feel it shift but my friends watching said they couldn't hear it shift. There was very little fall back.

When I ran the 340 with a 9 1/2" converter that flashed 5000, 727, 4.30 gears with a 275 radial, at 3260# it ran 7.24-28 at 94 mph with 1.54-58 60' and 11.60 at 116 on cal tracs.
 
justinp61 said:
Don, how did it feel onthe gear changes? When I killed one of my converters it felt like it slid into gear. I could hear and feel it shift but my friends watching said they couldn't hear it shift. There was very little fall back.

When I ran the 340 with a 9 1/2" converter that flashed 5000, 727, 4.30 gears with a 275 radial, at 3260# it ran 7.24-28 at 94 mph with 1.54-58 60' and 11.60 at 116 on cal tracs.
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Second to third shift felt like a new car, not sure how else to describe it. Car is remarkably consistent to the 1/8 mile, as i said all the mph and ET’s were the same on every pass.
It was only in high gear where the mph was off.
Not sure exactly what your combo was, they are all different.... lol.
This 360 is literally bone stock. Stock crank, rods, and stock 30 over factory replacement cast slugs, factory 28 thou in the hole. I milled the heads to up the compression a bit
Big cam, dinky 1 5/8 tube headers and factory flat steel hood with no scoop.
It actually made very good mph with the 727 ( 118+) last year, for what it is, was extremely happy. I figured it would go 120 ish with the new convertor and this tranny. I think like 340Rick does( my buddy who called) the tranny is slipping.... hurting trap mph and slowing the back half of the track results down. I figured the car would run 11.20’s last night, and in great air threaten the 10’s
I mean, running 11.39 at 113 mph, something aint right.... lol.......
Here are the incrementals on that pass:
60 foot.... 1.553
330.........4.60
1/8..........7.201
1/8 mph....94.12
1000 et......9.459
1000 mph....107.71
1/4...........11.395
1/4 mph......113.35

Something aint right there........

Edit..... and here are the incrimentals a short while later( same air)

60 foot...... 1.554
330............4.614
1/8 mile......7.206
1/8... mph...94.56
1000......... 9.456
1000 mph.....108.15
1/4...............11.374
1/4 mph.........116.94

Still “off” but better...... this pass and the one above are the quickest the car has ever been other than on that last mineshaft air outing last year..... and even that night, only that one pass was in the 20’s......... its just not picking up from the 1/8 to the finish line..... its worse.
 
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Do you think it's possible it's driving through the converter in high gear? Take it out on the street and after it's good and warm and in high gear slow it down to 15-20 mph and flat foot the throttle, if the transmission is slipping or the converter is bad it'll show up.

BTW, you car runs very well for what it is.
 
justinp61 said:
Do you think it's possible it's driving through the converter in high gear? Take it out on the street and after it's good and warm and in high gear slow it down to 15-20 mph and flat foot the throttle, if the transmission is slipping or the converter is bad it'll show up.

BTW, you car runs very well for what it is.
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How would i tell which is the problem?..... btw i took that 7.20 the car kept running last night in the 1/8 and all the online calculators say that equates to an 11.23( exactly where i figured the car would run last night) as its geared more to running 1/4 mile....... but it was runnng high 30’s. Something in the backhalf sure isnt right
 
If you do as I suggested and something does slip I'd pull the pan and check for debris. I had my pan off several times checking band adjustment and looking for trash, finally figured it was the converter after it started slipping pretty bad. My skull is pretty thick. lol
 
Did you happen to notice what the drop back was on the shifts and what did it cross at.Also does the 904 have the low set in it.Other thought was any wind that night it plays havoc with my mph.
 
scampy said:
Did you happen to notice what the drop back was on the shifts and what did it cross at.Also does the 904 have the low set in it.Other thought was any wind that night it plays havoc with my mph.
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Crossed at 6500, about 300 more than last year. Didnt notice dropback. Not a low gear. Standard gearset
 
Yea the numbers listed from the slips are weird,that last one was like .5mph faster at 1000 but picked 3 from 1000 to 1320 from previous,where these in the same lane or some gust of wind?????
Other thing would be to see what that converter is dropping back to may be out of the power band,could try bringing the shift point back down,but if there is something wrong with trans all bets are off
 
scampy said:
Yea the numbers listed from the slips are weird,that last one was like .5mph faster at 1000 but picked 3 from 1000 to 1320 from previous,where these in the same lane or some gust of wind?????
Other thing would be to see what that converter is dropping back to may be out of the power band,could try bringing the shift point back down,but if there is something wrong with trans all bets are off
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Same lane, same night, same DA. Next time out gonna shift it at 6 like i always have in the past and see what happens. Might have went the wrong way shifting it at 6500.
Car still picked up a good tenth and a half in ET over what i would have run with the old tranny. Maybe my expectations werent realistic
 
B3422w5 said:
Same lane, same night, same DA. Next time out gonna shift it at 6 like i always have in the past and see what happens. Might have went the wrong way shifting it at 6500.
Car still picked up a good tenth and a half in ET over what i would have run with the old tranny. Maybe my expectations werent realistic
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Can u say convertor slippage !
The looser the convertor, the more slippage , about 100% of the time./ The best hi dollar convertors will not be as bad, but it is still there!-------FLUID COUPLING.
 
Sorry, what intake is up top now?
RPM - M1?
 
Thanks.

I think your doing the right thing. 1 change at a time. Then sort it out. IMO, pay attention to the trans/converter right now.
I think your just about at the boarder line between the intakes.
Between the intakes, I truly think the rpm is better for the current combo. IMO, the M1 will loose a little bit of time even if it is modified for a Holley for betterment.

In a way I envy your position. I’m constantly getting a bit of Murphy’s law handed to me. At least the wife’s car is 98% finished. Now if she stop chirping in my ear... oh the joy.... I may get to my junk....
LOL, pipe dreams I tell ya!

Keep at it. This is the point in time where it is frustrating as hell. Something I miss when I’m not doing it and something I don’t miss when I’m in the thick of it.
 
rumblefish360 said:
Thanks.

I think your doing the right thing. 1 change at a time. Then sort it out. IMO, pay attention to the trans/converter right now.
I think your just about at the boarder line between the intakes.
Between the intakes, I truly think the rpm is better for the current combo. IMO, the M1 will loose a little bit of time even if it is modified for a Holley for betterment.

In a way I envy your position. I’m constantly getting a bit of Murphy’s law handed to me. At least the wife’s car is 98% finished. Now if she stop chirping in my ear... oh the joy.... I may get to my junk....
LOL, pipe dreams I tell ya!

Keep at it. This is the point in time where it is frustrating as hell. Something I miss when I’m not doing it and something I don’t miss when I’m in the thick of it.
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Agree. The rpm is helping the combo more than even a victor would right now. Frankly, i have had a number of different manifolds on smallblocks over the years, and generally swapping doesnt do much one way or the other on an ET slip. Street strip deal a dual plane is a good choice, high compression, higher rpm race motir likes a single plane. This combo i have is definately the former of the two.
I called PTC Thursday afternoon about this new convertor they built for me and what its doing. Guy i talked to said he was going to discuss it with Kenny Ford and call me back. Have yet to hear from them.
I dont know enough about convertors to know if i can keep my 1/2 track gains and have it tightened up in high gear.
For the next outing i will lower my shiftpoints to what they were before and see if it riding on the convertor more helps with torque multiplication, maybe by upping my shiftpoints 500 rpm i went the wrong way.
 
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