run 4+3 as a regular 4 speed?
Thread Starter
Drifting
Joined: Sep 2004
Posts: 1,638
Likes: 3
run 4+3 as a regular 4 speed?
seems to me this has been asked about a few times - but I'm too stoopid to make the search function properly.
I am currently putting a Big Block into an 88. as part of that process i am replacing the 700R4 with a manual transmission. The car is being built for running Bonneville and El Mirage dry lake bed speed trials.
i want a 4 speed with a 1:1 final drive, that gives me optimal gearing to go with RPM and tire size to reach 225mph.
It seems to me intead of reinventing the wheel and go about fabbing up all sorts of adaptors etc - it would be easy to bolt in the 4+3 I removed from my 86. The 4 speed worked great - the OD never worked - so essentially I would just run it as a 4 speed. But I wouldn't have to do alot of adapting to make it all fit together.
So whats going to happen if I just ignore the OD unit and run the snot out of the 4 speed? will fluids mix and doom the 4 speed?
Carl Johansson
I am currently putting a Big Block into an 88. as part of that process i am replacing the 700R4 with a manual transmission. The car is being built for running Bonneville and El Mirage dry lake bed speed trials.
i want a 4 speed with a 1:1 final drive, that gives me optimal gearing to go with RPM and tire size to reach 225mph.
It seems to me intead of reinventing the wheel and go about fabbing up all sorts of adaptors etc - it would be easy to bolt in the 4+3 I removed from my 86. The 4 speed worked great - the OD never worked - so essentially I would just run it as a 4 speed. But I wouldn't have to do alot of adapting to make it all fit together.
So whats going to happen if I just ignore the OD unit and run the snot out of the 4 speed? will fluids mix and doom the 4 speed?
Carl Johansson
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
There are trannies available that will bolt right in and be much stronger than the 4+3 unit. Keisler and Richmond Gear have 5 and 6 speed units that have mounting flanges for the C-beam and fit with almost no modifications (mods would be around the tranny tunnel and console to get the shifter to clear. Any of these trannies have a 1:1 ration in 4th or 5th depening on the particular unit. You can also get a couple different 1st gear ratios that could help the car get rolling without a lot of initial wheelspin.
While the 4+3 handled the power from the 87 and 88 Callaway twin-turbo motors, I would think that 500 HP and the large abount of torque that rat motors can generate would put a hard (if not fatal) strain on the 4+3.
You can try the 4+3 but given that there are bolt-in alternatives, it may be easier to upgrade as the car is built.
While the 4+3 handled the power from the 87 and 88 Callaway twin-turbo motors, I would think that 500 HP and the large abount of torque that rat motors can generate would put a hard (if not fatal) strain on the 4+3.
You can try the 4+3 but given that there are bolt-in alternatives, it may be easier to upgrade as the car is built.
Thread Starter
Drifting
Joined: Sep 2004
Posts: 1,638
Likes: 3
I appreciate your input. I am familiar with the tremek tko 500 - I have it in my 86. and I just purchased a richmond 6 speed to go into a 1000 hp studebaker we are building. I know conventional wisdom doesn't think that the 4 + 0 would hold up to the 718 hp we will be putting through it - but remember the application - no hard launches - running on a surface with considerable "slip", lots of time to get to speed. Trannies hold up OK out there. Besides I already have the 4+3 hulk sitting there, and could mount it up with no problems (or at least minimal issues) If it fails - I'm out nothing - and move on to plan B, but if it works -well goodie for me I just saved 3500 bucks!
Isn't the 4+5 just a T-5 with a bastardized autotrans bolted on to the rear? so what kind of power would a T-5 hold?
I'm just looking to find out if the trans would be fine - no damage by just ignoring the OD - or do we need to seal off something / remove something? in order to keep the tranny from eating itself!
Carl Johansson
Isn't the 4+5 just a T-5 with a bastardized autotrans bolted on to the rear? so what kind of power would a T-5 hold?
I'm just looking to find out if the trans would be fine - no damage by just ignoring the OD - or do we need to seal off something / remove something? in order to keep the tranny from eating itself!
Carl Johansson
There are trannies available that will bolt right in and be much stronger than the 4+3 unit. Keisler and Richmond Gear have 5 and 6 speed units that have mounting flanges for the C-beam and fit with almost no modifications (mods would be around the tranny tunnel and console to get the shifter to clear. Any of these trannies have a 1:1 ration in 4th or 5th depening on the particular unit. You can also get a couple different 1st gear ratios that could help the car get rolling without a lot of initial wheelspin.
While the 4+3 handled the power from the 87 and 88 Callaway twin-turbo motors, I would think that 500 HP and the large abount of torque that rat motors can generate would put a hard (if not fatal) strain on the 4+3.
You can try the 4+3 but given that there are bolt-in alternatives, it may be easier to upgrade as the car is built.
While the 4+3 handled the power from the 87 and 88 Callaway twin-turbo motors, I would think that 500 HP and the large abount of torque that rat motors can generate would put a hard (if not fatal) strain on the 4+3.
You can try the 4+3 but given that there are bolt-in alternatives, it may be easier to upgrade as the car is built.
Safety Car
Joined: Jan 2006
Posts: 3,566
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From: Mt Laurel NJ
St. Jude Donor '06-'07
A 4+3 tranny is just a munce (sp) w/ a two speed tranny mounted in place of the tailshaft. I am sure you could use it, just make sure the OD has tranny fluid in it so it will nor seize up. You could also use a T5, as they bolt up to the same bellhousing. You would have the buy an adapter for the C beam, and mod the shifter, but your race car doesn't have an interior, does it?
Thread Starter
Drifting
Joined: Sep 2004
Posts: 1,638
Likes: 3
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
The 4+3 is a Borg-Warner Super T-10. Dough Nash bought the rights to make the gearbox and then designed the OD unit to attach to it.
I don't think any T-5, even the "World Class" version would hold up to those HP numbers for any length of time.
I would add a separate cooler to the OD fluid lines instead of running to the radiator like an auto trans setup to make sure the fluid is kept at a reasonable temp. This is one case where a synthetic Dexron III/ Mercon ATF fluid might be a better deal. Install a new filter (it's the same one used in a Ford FMX tranny) and give it a try.
The 4+3 shifter bolts to the body and not the tranny so you will have to fab up the braces and attaching points to get the shifter in the right spot. There is no place on the 4+3 to attach a Hurst or similar shifter.
Is wheelspin a big problem on the salt? I would think that would put lots of strain on the tranny and the u-joints if the tires slip and grab a lot until you get towards top speed.
I don't think any T-5, even the "World Class" version would hold up to those HP numbers for any length of time.
I would add a separate cooler to the OD fluid lines instead of running to the radiator like an auto trans setup to make sure the fluid is kept at a reasonable temp. This is one case where a synthetic Dexron III/ Mercon ATF fluid might be a better deal. Install a new filter (it's the same one used in a Ford FMX tranny) and give it a try.
The 4+3 shifter bolts to the body and not the tranny so you will have to fab up the braces and attaching points to get the shifter in the right spot. There is no place on the 4+3 to attach a Hurst or similar shifter.
Is wheelspin a big problem on the salt? I would think that would put lots of strain on the tranny and the u-joints if the tires slip and grab a lot until you get towards top speed.
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Verdad Gallardo
Team Owner
Joined: Aug 1999
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St. Jude Donor '10
You can get a bronze clutch kit from SK Speed, for the 4+3. Its not meant for street use.
The real killer of the 4+3 is the auto kick down and lack of maintenance. The 700lbs of torque my B2k put out thrashed one in no time flat. However using the clutch to shift remedied the problem as best I could tell...as well as hearing from other Callaway owners.
I think if you build it right, change the OD fluid and clutch shift if you'll be find.
The real killer of the 4+3 is the auto kick down and lack of maintenance. The 700lbs of torque my B2k put out thrashed one in no time flat. However using the clutch to shift remedied the problem as best I could tell...as well as hearing from other Callaway owners.
I think if you build it right, change the OD fluid and clutch shift if you'll be find.
Thread Starter
Drifting
Joined: Sep 2004
Posts: 1,638
Likes: 3
The 4+3 is a Borg-Warner Super T-10. Dough Nash bought the rights to make the gearbox and then designed the OD unit to attach to it.
I don't think any T-5, even the "World Class" version would hold up to those HP numbers for any length of time.
I would add a separate cooler to the OD fluid lines instead of running to the radiator like an auto trans setup to make sure the fluid is kept at a reasonable temp. This is one case where a synthetic Dexron III/ Mercon ATF fluid might be a better deal. Install a new filter (it's the same one used in a Ford FMX tranny) and give it a try.
The 4+3 shifter bolts to the body and not the tranny so you will have to fab up the braces and attaching points to get the shifter in the right spot. There is no place on the 4+3 to attach a Hurst or similar shifter.
Is wheelspin a big problem on the salt? I would think that would put lots of strain on the tranny and the u-joints if the tires slip and grab a lot until you get towards top speed.
I don't think any T-5, even the "World Class" version would hold up to those HP numbers for any length of time.
I would add a separate cooler to the OD fluid lines instead of running to the radiator like an auto trans setup to make sure the fluid is kept at a reasonable temp. This is one case where a synthetic Dexron III/ Mercon ATF fluid might be a better deal. Install a new filter (it's the same one used in a Ford FMX tranny) and give it a try.
The 4+3 shifter bolts to the body and not the tranny so you will have to fab up the braces and attaching points to get the shifter in the right spot. There is no place on the 4+3 to attach a Hurst or similar shifter.
Is wheelspin a big problem on the salt? I would think that would put lots of strain on the tranny and the u-joints if the tires slip and grab a lot until you get towards top speed.
wheel spin is the big problem - but it is consistant - not really grabby and loose - it's always there - consistantly. Bikes going 200 mph ground speed often show indicated speeds of 220 mph.
300 mph cars come back to the pits with their tires smoking from spinning even at 300,. We figure 10% loss to the salt - some years it's less - other years it's better!
The big issue is getting the traction to put the power to the ground - thats why the very thin (4.5" wide) tires and adding lead and other ballast to the cars. Some of the high powered cars weigh in excess of 9K lbs - half of that being lead! They are after lots of weight on a tiny contact patch. It's almost the antithesis (did I spell that correctly) I mean it's almost exactly opposite of drag racing!
Carl Johansson
Thread Starter
Drifting
Joined: Sep 2004
Posts: 1,638
Likes: 3
I'll keep you guys posted - right now I have to clear my plate - I really want to get started on the 88 - but I'm in the middle of an engine swap for my Bobcat - hopefully thats done by saturday - then I have to tear into a Junk Supra - we just got accepted into the 24 hours of lemons race in california between Christmas and new years (you can google it up if your interested) . To make a long story short you have to run a 500 dollar POS car (not including safety items).
So I found a junker for 100 bucks and have to get it running and handling for less than 400 bucks. My brothers and I will be driving it - but of course they are in Michigan and Utah - so guess who does all the prep - they just show up - drive and probably wreck - then go home leaving me with a wrecked POS!
After that - we get to work on the Bonneville car - the engine is ready - sitting there - I can't wait - but I have to clear these other projects first (damn I wish I was unemployed! I could use the extra time for doing good and fighting evil!)
Carl Johansson
So I found a junker for 100 bucks and have to get it running and handling for less than 400 bucks. My brothers and I will be driving it - but of course they are in Michigan and Utah - so guess who does all the prep - they just show up - drive and probably wreck - then go home leaving me with a wrecked POS!
After that - we get to work on the Bonneville car - the engine is ready - sitting there - I can't wait - but I have to clear these other projects first (damn I wish I was unemployed! I could use the extra time for doing good and fighting evil!)
Carl Johansson
