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Whose 727 street/strip converters are you using? #2709518
10/23/19 01:24 PM
10/23/19 01:24 PM
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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BradH Offline OP
Taking time off to work on my car
BradH  Offline OP
Taking time off to work on my car
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Val-haul-ass... eventually
I have the same Dynamic 9.5" that I bought in '99(?) and it's still in good shape given how little my car's been running over the years. However, it was spec'd for the car when it was making maybe 550 HP and running very low 11s. The converter still seemed to work well w/ the 50+ HP increase that put the car into the mid 10s, so I was happy.

However, the new engine is an easy 100+ HP more than the converter was spec'd for originally in '99. It's still going to be my baseline when the car is back together, but at some point I a$$ume it's either going to need to be re-configured for the new engine... or perhaps I'll want (need?) to change to another converter.

So, as my subject line states, whose 727 street/strip converters are you using? work

Re: Whose 727 street/strip converters are you using? [Re: BradH] #2709520
10/23/19 01:38 PM
10/23/19 01:38 PM
Joined: Jan 2016
Posts: 216
America
WedgeFED Offline
enthusiast
WedgeFED  Offline
enthusiast

Joined: Jan 2016
Posts: 216
America
http://www.tcsperformance.com/performance_converters/

have been good to us. good customer service and quality

Re: Whose 727 street/strip converters are you using? [Re: WedgeFED] #2709523
10/23/19 01:42 PM
10/23/19 01:42 PM
Joined: Jan 2003
Posts: 1,237
North Central, Indiana
Roughbird72 Offline
pro stock
Roughbird72  Offline
pro stock

Joined: Jan 2003
Posts: 1,237
North Central, Indiana
PTC


72 Plymouth Roadrunner 11.08@123.25
Re: Whose 727 street/strip converters are you using? [Re: BradH] #2709549
10/23/19 02:58 PM
10/23/19 02:58 PM
Joined: Oct 2007
Posts: 4,205
New York
polyspheric Offline
master
polyspheric  Offline
master

Joined: Oct 2007
Posts: 4,205
New York
The question is "how much torque does the new engine make at the observed stall speed?"
It may have less than the original engine (later intake closing = lower CCP) and will stall lower despite the higher peak power.

If the stall torque is higher, the stall speed will increase (duh) by the ratio of (new torque ÷ old torque)^.5
RPM = K × (T^.5)

Just using easy numbers:
Stall now 3,500, new torque 550, old torque 500
(550 ÷ 500)^,5 = 1.0488, × 3,500 = 3,671 RPM new stall
Stall now 3,500, new torque 600, old torque 500
Same math = 3,834 RPM new stall

Whether this helps or hurts launch...?


Boffin Emeritus
Re: Whose 727 street/strip converters are you using? [Re: BradH] #2709558
10/23/19 03:06 PM
10/23/19 03:06 PM
Joined: Feb 2003
Posts: 1,098
Massillon, Ohio
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cudatom Offline
super stock
cudatom  Offline
super stock
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Joined: Feb 2003
Posts: 1,098
Massillon, Ohio
PTC.


Ok
Re: Whose 727 street/strip converters are you using? [Re: polyspheric] #2709564
10/23/19 03:35 PM
10/23/19 03:35 PM
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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BradH Offline OP
Taking time off to work on my car
BradH  Offline OP
Taking time off to work on my car
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Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
Originally Posted by polyspheric
The question is "how much torque does the new engine make at the observed stall speed?"
It may have less than the original engine (later intake closing = lower CCP) and will stall lower despite the higher peak power.

If the stall torque is higher, the stall speed will increase (duh) by the ratio of (new torque ÷ old torque)^.5
RPM = K × (T^.5)

Just using easy numbers:
Stall now 3,500, new torque 550, old torque 500
(550 ÷ 500)^,5 = 1.0488, × 3,500 = 3,671 RPM new stall
Stall now 3,500, new torque 600, old torque 500
Same math = 3,834 RPM new stall

Whether this helps or hurts launch...?

Converter flashed to ~4500 from 2000 launch w/ old engine combination, so I highlighted the #s at 4500 for comparison. Your formula shows about a 4600 stall w/ additional torque. shruggy

10.2017 BSH RB452 dyno_2.jpg
Re: Whose 727 street/strip converters are you using? [Re: BradH] #2709577
10/23/19 04:26 PM
10/23/19 04:26 PM
Joined: Mar 2009
Posts: 2,457
Sydney,Australia
tex013 Offline
top fuel
tex013  Offline
top fuel

Joined: Mar 2009
Posts: 2,457
Sydney,Australia
Brad ,
I ran a similar Dynamic/Lupo to you for years stalled around 48/4900 . This was with both 440 and 505 footbraking .
Now with transbrake I have a A1 Performance 8" unit , stalled at 5800 with original 505 and 440 . When I went TF270 head stall went to 6000 , but car went 0.25 faster so the heads obviously helped the motor HP wise.
Drives fine daily . Even drove to a race in Mildura on the other side of the state - 12 1/4 hours on the highway no dramas . Tis was 2 weeks ago .

Tex


New best ET 10.259@129.65 .
New best MPH 130.32
Finally fitted a solid cam,
stepped it up a bit more
3690lbs through the mufflers
New World block 3780lbs 10.278@130.80 . Wowser 10.253@130.24 footbraking from 1500rpm
Power by Tex's Automotive
Re: Whose 727 street/strip converters are you using? [Re: tex013] #2709590
10/23/19 05:14 PM
10/23/19 05:14 PM
Joined: Jan 2003
Posts: 8,005
Tulsa OK
Bad340fish Offline
master
Bad340fish  Offline
master

Joined: Jan 2003
Posts: 8,005
Tulsa OK
I have loads of street miles on a Turbo Action 8" 4500 when I had my 727. My 904 had a 8" 4800 until the snout broke but that is getting repaired. The 4500 behind the 727 flashed to about 5500 and the 4800 with the 904 flashes to 6400. I did 5 drag weeks with the 727 converter and 1 with the 904, car weight on the road for drag week is around 4000ish.

The street manners of them don't bother me at all.


68 Barracuda Formula S 340
87 "Chrysler" Conquest
Re: Whose 727 street/strip converters are you using? [Re: Bad340fish] #2709598
10/23/19 05:52 PM
10/23/19 05:52 PM
Joined: May 2003
Posts: 2,117
Cleveland Ohio
10secGTX Online happy
top fuel
10secGTX  Online Happy
top fuel

Joined: May 2003
Posts: 2,117
Cleveland Ohio
8" ATI Tree master about 18 yrs old with one refresh it has great street manners also

Re: Whose 727 street/strip converters are you using? [Re: BradH] #2709606
10/23/19 06:29 PM
10/23/19 06:29 PM
Joined: Oct 2007
Posts: 4,205
New York
polyspheric Offline
master
polyspheric  Offline
master

Joined: Oct 2007
Posts: 4,205
New York
That's not "my formula", it's the one the transmission and converter manufacturers use.


Boffin Emeritus
Re: Whose 727 street/strip converters are you using? [Re: polyspheric] #2709662
10/23/19 09:28 PM
10/23/19 09:28 PM
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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BradH Offline OP
Taking time off to work on my car
BradH  Offline OP
Taking time off to work on my car
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Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
Regardless, it calcs right at 100 RPM increase.

Know of any formula to help quantify converter slippage increase resulting from torque increase? It would be interesting to know if there is a way to help predict at what point you are likely to start "driving through" a known converter when the power level is stepped up.

Re: Whose 727 street/strip converters are you using? [Re: BradH] #2709664
10/23/19 09:37 PM
10/23/19 09:37 PM
Joined: Jan 2003
Posts: 1,800
North Dakota
Azzkikrcuda Offline
top fuel
Azzkikrcuda  Offline
top fuel

Joined: Jan 2003
Posts: 1,800
North Dakota
Turbo Action or PTC, never had any issues with either one.


The only Carbs I care about are under the hood!
Re: Whose 727 street/strip converters are you using? [Re: Azzkikrcuda] #2709670
10/23/19 09:47 PM
10/23/19 09:47 PM
Joined: Apr 2005
Posts: 98
ma.
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duspan Offline
member
duspan  Offline
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Joined: Apr 2005
Posts: 98
ma.
ptc is very good,they have a mopar guy that is real good with converter combo!!!

Re: Whose 727 street/strip converters are you using? [Re: BradH] #2709679
10/23/19 10:08 PM
10/23/19 10:08 PM
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Posts: 1,979
s. e. pa.
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calrobb2000 Offline
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s. e. pa.

hi ,

the dynamic worked good for 20 years and you want to know where to get a converter ?

Re: Whose 727 street/strip converters are you using? [Re: calrobb2000] #2709705
10/24/19 06:29 AM
10/24/19 06:29 AM
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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BradH Offline OP
Taking time off to work on my car
BradH  Offline OP
Taking time off to work on my car
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Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
Originally Posted by calrobb2000

hi ,

the dynamic worked good for 20 years and you want to know where to get a converter ?

My Dynamic has worked very well so far. My friend's sucked. Nobody hits 100%, and converter tech & good builders can change over 20 years. If the new engine and the old converter aren't a good match, I'd like to know what other people's experiences have been.

Re: Whose 727 street/strip converters are you using? [Re: BradH] #2709719
10/24/19 07:57 AM
10/24/19 07:57 AM
Joined: Jan 2007
Posts: 8,027
Mt Morris Michigan
mopar dave Offline
master
mopar dave  Offline
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Posts: 8,027
Mt Morris Michigan
When I bought my 8" vert from Dynamics I told them I wanted it to flash 5200. It was dead nuts 5200. Can't get any better than that.

Re: Whose 727 street/strip converters are you using? [Re: mopar dave] #2709731
10/24/19 09:15 AM
10/24/19 09:15 AM
Joined: Jan 2003
Posts: 11,701
Portage,michigan
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B3422W5 Offline
I Live Here
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I Live Here
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Joined: Jan 2003
Posts: 11,701
Portage,michigan
PTC
Mopar racer owned


69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight
418 BPE factory replacement headed stroker, 565 lift solid cam
Best so far, 10.40 @127 1/4
1.41 best 60 foot
6.60 at 103.90 1/8

Re: Whose 727 street/strip converters are you using? [Re: BradH] #2709733
10/24/19 09:16 AM
10/24/19 09:16 AM
Joined: Aug 2011
Posts: 2,842
Pattison Texas
CSK Offline
master
CSK  Offline
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Joined: Aug 2011
Posts: 2,842
Pattison Texas
For my A518 I had PATC custom build mine, told them my engine combo & they nailed it, so far so good, 3500miles of abuse .


1968 Charger COLD A/C Hilborn EFI
512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim
2020 T/A 392 Stock 11.79 @ 114.5

Re: Whose 727 street/strip converters are you using? [Re: Azzkikrcuda] #2709878
10/24/19 08:50 PM
10/24/19 08:50 PM
Joined: May 2004
Posts: 12,379
Taxes & Virus's R-US, NY
Dragula Offline
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Dragula  Offline
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Joined: May 2004
Posts: 12,379
Taxes & Virus's R-US, NY
ATI here......Getting one for a big engine like mine wasn't easy....Love it.


'70 Cuda,...605 EFI Hemi Street Car (6.20 best pass, 1.33 60ft)
https://www.youtube.com/watch?v=WYw6RA-k5Bk (6.25 at 108.75mph from inside car)
https://www.youtube.com/watch?v=3zQEb9uxFng (6.25 at 108mph from outside car)
https://www.youtube.com/watch?v=JCvfzsC4NgM (9.9)

'66 Barracuda AWB Stretched nose Blown 440 Car in build stage

'71 Duster Drag Car 400 Low Deck 512 best 6.002 at 115.44mph
https://www.youtube.com/watch?v=Znuo3jMUXTk
Re: Whose 727 street/strip converters are you using? [Re: Dragula] #2709926
10/25/19 07:39 AM
10/25/19 07:39 AM
Joined: Aug 2004
Posts: 214
Hamburg / Germany
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Den300 Offline
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Den300  Offline
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Joined: Aug 2004
Posts: 214
Hamburg / Germany
FTI - great Service! Switched from a 9.5" PTC with 3200 stall to a 9.5" FTI with 3500 stall. Day and night difference! Much better.


Hamburg/Germany

69 Chrysler 300
446cui Dual Quad
12.64 @ 110.7

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