C3 Diff gearing for TH700
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Joined: Nov 2014
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Hey this is a great thread! Thank you! I plan on putting that same 383 crate motor in mine soon and have been wondering about all the same drive train questions. This thread is definitely helping me make up my mind. I also plan on using the car often in both around town and some hi way driving. I think I'll be using the 700R4 with overdrive to keep the rpm's lower for the hi way driving?
Thanks all,
Tom
Thanks all,
Tom
Last edited by Tommy K 47; Nov 10, 2015 at 10:01 PM.
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Joined: Mar 2007
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From: Bridgewater nj
The 700R4 has a very low 1st gear so snappy isn't a problem. My stock 82 is running a 2:73 rear and it will break the wheels loose easily off the line and even a rolling start. That's with 255-60,15 tires.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Actually in a lower powered car a 200R4 has better gear ratios and uses less RWHP and no drive line length to change. The 200's can be built to take on maybe 600 hp at lower TQ numbers. the 700 like i had was about a 800 hp model with all the best upgrades available. they claimed like 850 but who knows.
Unless you have to have an auto tranny they both burn up HP.
Unless you have to have an auto tranny they both burn up HP.
Thread Starter
Cruising
Joined: Nov 2015
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Actually in a lower powered car a 200R4 has better gear ratios and uses less RWHP and no drive line length to change. The 200's can be built to take on maybe 600 hp at lower TQ numbers. the 700 like i had was about a 800 hp model with all the best upgrades available. they claimed like 850 but who knows.
Unless you have to have an auto tranny they both burn up HP.
Unless you have to have an auto tranny they both burn up HP.
69 vet TH700 30 spine box, 3.73 diff, 2800 9.5 inch torque converter with lockup,
383 455 hp, Cam rpm range 2400-5800,
How does that look guys, Vote now? so i can place my order.
Thread Starter
Cruising
Joined: Nov 2015
Posts: 11
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ok i think i've come to the final setup guys taking into account all the great advice on the forum.
69 vet TH700 30 spine box, 3.73 diff, 2800 9.5 inch torque converter with lockup,
383 455 hp, Cam rpm range 2400-5800,
How does that look guys, Vote now? so i can place my order.
69 vet TH700 30 spine box, 3.73 diff, 2800 9.5 inch torque converter with lockup,
383 455 hp, Cam rpm range 2400-5800,
How does that look guys, Vote now? so i can place my order.
The only parts that are variables are diff ratio, Torque converter,
and possibly the next cam down that has a rpm range of 1600-5400. the rest is already installed.
Cheers
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
What you saying makes sense.
Below are my Cam specs.
Hydraulic Roller Camshafts for OE Roller Applications
180265-10 Duration @ .050 IN 233 OUT 241
2400-5800 rpm Rough idle, Hot Street & Bracket Racing. 10.0:1-up CR 2800 rpm + stall
This seems to be going pear shape?
I either work with this or get the next cam down that's milder with a 1600 to 5400 rpm range.
Below are my Cam specs.
Hydraulic Roller Camshafts for OE Roller Applications
180265-10 Duration @ .050 IN 233 OUT 241
2400-5800 rpm Rough idle, Hot Street & Bracket Racing. 10.0:1-up CR 2800 rpm + stall
This seems to be going pear shape?
I either work with this or get the next cam down that's milder with a 1600 to 5400 rpm range.
I had something like this in my first 383 only the Solid roller.
this cam will have better idle qualities and higher MPG
http://www.summitracing.com/parts/hr...make/chevrolet
Last edited by gkull; Nov 11, 2015 at 12:08 PM.
Thread Starter
Cruising
Joined: Nov 2015
Posts: 11
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I don't know what kind of rods you have, but stroker motors need small base circle cams (less than .950)
I had something like this in my first 383 only the Solid roller.
this cam will have better idle qualities and higher MPG
http://www.summitracing.com/parts/hr...make/chevrolet
I had something like this in my first 383 only the Solid roller.
this cam will have better idle qualities and higher MPG
http://www.summitracing.com/parts/hr...make/chevrolet
I just checked it out, The brand and specs are nearly identical except it has a lopey idle, and its made for retro fit roller cam blocks.
Mine is a newer roller cam block.
Cheers
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
i'd call howard cams and ask about small base circle. Some cam companies go overboard and make .870 diameter base circles. Those look funny because the low point on the lobe is the same as the shaft.
The other problem with too small base circle is the added stress on the roller lifter wheel.
I overlooked the part that your block was a roller block. sorry. It took me three solid roller cams to get it right on my 383. The problem is I bought off the shelf billet steel small base cams. the first one was 232/238 .620/.645 and it had detonation because of my 11/1 compression. #2 was 242/248 .620/.645 It was a 3500 - 7500 rpm and not friendly even with a 3500 stall. I had big 227 cc heads and a single plane. So I went to some engine simulation software and spend days running profiles from the Comp Cams lobe profile catalog. I came up with the need to go down on the head cc side to AFR 210 cc and because of free flowing 3 inch exhaust that 236/242 112lc .644/.680
The lobes are much more aggressive than street roller cams. I also did some cam to rod clearance measuring and i found that .950 cleared my Manley 6 inch H beam rods
The other problem with too small base circle is the added stress on the roller lifter wheel.
I overlooked the part that your block was a roller block. sorry. It took me three solid roller cams to get it right on my 383. The problem is I bought off the shelf billet steel small base cams. the first one was 232/238 .620/.645 and it had detonation because of my 11/1 compression. #2 was 242/248 .620/.645 It was a 3500 - 7500 rpm and not friendly even with a 3500 stall. I had big 227 cc heads and a single plane. So I went to some engine simulation software and spend days running profiles from the Comp Cams lobe profile catalog. I came up with the need to go down on the head cc side to AFR 210 cc and because of free flowing 3 inch exhaust that 236/242 112lc .644/.680
The lobes are much more aggressive than street roller cams. I also did some cam to rod clearance measuring and i found that .950 cleared my Manley 6 inch H beam rods
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Thread Starter
Cruising
Joined: Nov 2015
Posts: 11
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i'd call howard cams and ask about small base circle. Some cam companies go overboard and make .870 diameter base circles. Those look funny because the low point on the lobe is the same as the shaft.
The other problem with too small base circle is the added stress on the roller lifter wheel.
I overlooked the part that your block was a roller block. sorry. It took me three solid roller cams to get it right on my 383. The problem is I bought off the shelf billet steel small base cams. the first one was 232/238 .620/.645 and it had detonation because of my 11/1 compression. #2 was 242/248 .620/.645 It was a 3500 - 7500 rpm and not friendly even with a 3500 stall. I had big 227 cc heads and a single plane. So I went to some engine simulation software and spend days running profiles from the Comp Cams lobe profile catalog. I came up with the need to go down on the head cc side to AFR 210 cc and because of free flowing 3 inch exhaust that 236/242 112lc .644/.680
The lobes are much more aggressive than street roller cams. I also did some cam to rod clearance measuring and i found that .950 cleared my Manley 6 inch H beam rods
The other problem with too small base circle is the added stress on the roller lifter wheel.
I overlooked the part that your block was a roller block. sorry. It took me three solid roller cams to get it right on my 383. The problem is I bought off the shelf billet steel small base cams. the first one was 232/238 .620/.645 and it had detonation because of my 11/1 compression. #2 was 242/248 .620/.645 It was a 3500 - 7500 rpm and not friendly even with a 3500 stall. I had big 227 cc heads and a single plane. So I went to some engine simulation software and spend days running profiles from the Comp Cams lobe profile catalog. I came up with the need to go down on the head cc side to AFR 210 cc and because of free flowing 3 inch exhaust that 236/242 112lc .644/.680
The lobes are much more aggressive than street roller cams. I also did some cam to rod clearance measuring and i found that .950 cleared my Manley 6 inch H beam rods
Cheers