Stall speed question.....355 sbc

casrak7 · 12-27-2016, 12:55 PM

I have a 355, solid roller, ported dart heads, makes 544hp@7100, 448ft.lbs@5700...........UNFORTUNATELY.......the top end and camshaft surpass what the bottom end is capable of handling reliably. I dont mind shifting/and or crossing at 7400 or so (1/4 mile).......but I'm leary of much higher. I still want ONLY MAX ET for this combination. ET is my ONLY concern. How would you make a converter for this application? Since I will gear the car to cross at 7400-7500 rpm........which I'm thinking should go around 10.0@130-131 if things go correctly (2850 lbs w driver)........4.56 gear, 28" tire, roughly 5-7% conv. slip..............Probably be a footbrake only deal.........

casrak7 · 12-27-2016, 12:57 PM

Im aware that the car would shift around 7500-7600 normally, and maybe cross at 8100 under normal circumstances........but how would I converter this around the peak rpm restrictions? Oops...and TH-350, stock gearing.

Jeff Stout · 12-27-2016, 01:49 PM

Ck your PM

Mike Pearson · 12-27-2016, 03:43 PM

Unless your car is real light 10.0 will not be possible with the HP you have listed. That would be more like 10.90. Most 350 engines like a 6000 rpm stall speed. My car runs in the low 10 - High 9 second range and makes 620 HP approx. 3150 lbs.

casrak7 · 12-27-2016, 06:00 PM

Car is 2775-2825 w driver. 2850 w full tank of fuel.

Ed Wright · 12-27-2016, 07:18 PM

I would gather my dyno data, and call. ATI. Provide the data they ask for, and buy what they tell you is needed. Don't try to tell them "Everybody says I need....) There are some sharp guys here, but as far as needed converters, it doesn't really matter what anybody here says. Believe what somebody like Charlie Plott there says what you need.
It will be correct.

joespanova · 12-27-2016, 08:30 PM

Quote:

Originally Posted by Mike Pearson

Unless your car is real light 10.0 will not be possible with the HP you have listed. That would be more like 10.90. Most 350 engines like a 6000 rpm stall speed. My car runs in the low 10 - High 9 second range and makes 620 HP approx. 3150 lbs.

X2......
I think mid 10s is likely though

casrak7 · 12-27-2016, 11:45 PM

It might be. Who knows. Anything we have usually runs within 2/10ths of the slide rule.......it says 9.90. I hope....but if it doesnt, no big deal.

Ed Wright · 12-28-2016, 07:30 PM

Why don't you ask the guys where your going to buy your converter?
There is more to it than stall RPM.
A given converter won't flash to the same RPM behind just any engine, in just any weight car. Your torque peak RPM has more to do with it than your hp peak RPM.

cad · 12-29-2016, 11:44 AM

Call ATI and order a converter. It will be right.

My 68 Camaro with a 385 (6" rods), AFR 220s, powerglide 1.76, 4.88, 28" tire went 10.53 @ 127 at 3280 lbs @ 2600' DA in topeka last Sept.
10.92 with my 383 (400ci rods) AFR 195s and same converter
ATI converter.

12-27-2016, 12:55 PM	#1
casrak7 Junior Member Join Date: Jul 2011 Posts: 63 Likes: 0 Liked 3 Times in 2 Posts	Stall speed question.....355 sbc I have a 355, solid roller, ported dart heads, makes 544hp@7100, 448ft.lbs@5700...........UNFORTUNATELY.......the top end and camshaft surpass what the bottom end is capable of handling reliably. I dont mind shifting/and or crossing at 7400 or so (1/4 mile).......but I'm leary of much higher. I still want ONLY MAX ET for this combination. ET is my ONLY concern. How would you make a converter for this application? Since I will gear the car to cross at 7400-7500 rpm........which I'm thinking should go around 10.0@130-131 if things go correctly (2850 lbs w driver)........4.56 gear, 28" tire, roughly 5-7% conv. slip..............Probably be a footbrake only deal.........

12-27-2016, 12:57 PM	#2
casrak7 Junior Member Join Date: Jul 2011 Posts: 63 Likes: 0 Liked 3 Times in 2 Posts	Re: Stall speed question.....355 sbc Im aware that the car would shift around 7500-7600 normally, and maybe cross at 8100 under normal circumstances........but how would I converter this around the peak rpm restrictions? Oops...and TH-350, stock gearing. Last edited by casrak7; 12-27-2016 at 01:01 PM.

12-27-2016, 01:49 PM	#3
Jeff Stout VIP Member Join Date: Dec 2001 Location: phoenix Posts: 1,486 Likes: 66 Liked 704 Times in 281 Posts	Re: Stall speed question.....355 sbc Ck your PM

12-27-2016, 03:43 PM	#4
Mike Pearson VIP Member Join Date: Mar 2007 Posts: 2,445 Likes: 614 Liked 1,919 Times in 576 Posts	Re: Stall speed question.....355 sbc Unless your car is real light 10.0 will not be possible with the HP you have listed. That would be more like 10.90. Most 350 engines like a 6000 rpm stall speed. My car runs in the low 10 - High 9 second range and makes 620 HP approx. 3150 lbs. __________________ Mike Pearson 2485 SS

12-27-2016, 06:00 PM	#5
casrak7 Junior Member Join Date: Jul 2011 Posts: 63 Likes: 0 Liked 3 Times in 2 Posts	Re: Stall speed question.....355 sbc Car is 2775-2825 w driver. 2850 w full tank of fuel. Last edited by casrak7; 12-27-2016 at 06:05 PM.

12-27-2016, 07:18 PM	#6
Ed Wright Veteran Member Join Date: Mar 2005 Location: Sand Springs, OK Posts: 8,132 Likes: 896 Liked 390 Times in 170 Posts	Re: Stall speed question.....355 sbc I would gather my dyno data, and call. ATI. Provide the data they ask for, and buy what they tell you is needed. Don't try to tell them "Everybody says I need....) There are some sharp guys here, but as far as needed converters, it doesn't really matter what anybody here says. Believe what somebody like Charlie Plott there says what you need. It will be correct. __________________ Ed Wright 4156 SS/JA Last edited by Ed Wright; 12-27-2016 at 07:22 PM.

12-27-2016, 11:45 PM	#8
casrak7 Junior Member Join Date: Jul 2011 Posts: 63 Likes: 0 Liked 3 Times in 2 Posts	Re: Stall speed question.....355 sbc It might be. Who knows. Anything we have usually runs within 2/10ths of the slide rule.......it says 9.90. I hope....but if it doesnt, no big deal.

12-28-2016, 07:30 PM	#9
Ed Wright Veteran Member Join Date: Mar 2005 Location: Sand Springs, OK Posts: 8,132 Likes: 896 Liked 390 Times in 170 Posts	Re: Stall speed question.....355 sbc Why don't you ask the guys where your going to buy your converter? There is more to it than stall RPM. A given converter won't flash to the same RPM behind just any engine, in just any weight car. Your torque peak RPM has more to do with it than your hp peak RPM. __________________ Ed Wright 4156 SS/JA

12-29-2016, 11:44 AM	#10
cad Senior Member Join Date: Apr 2009 Location: Omaha, NE Posts: 702 Likes: 202 Liked 91 Times in 51 Posts	Re: Stall speed question.....355 sbc Call ATI and order a converter. It will be right. My 68 Camaro with a 385 (6" rods), AFR 220s, powerglide 1.76, 4.88, 28" tire went 10.53 @ 127 at 3280 lbs @ 2600' DA in topeka last Sept. 10.92 with my 383 (400ci rods) AFR 195s and same converter ATI converter. Last edited by cad; 12-29-2016 at 11:47 AM.