Engine and Transmission Tech

Hello Guys . Need your help.Ive got an 84 Mustang/Capri non WC with a 295 first gear and a .63 fifth gear. The top gear is way to long and I want to change it to a .80 fifth gear. Looking on Ebay there is a gear set available to do this It has a 5th counter gear with32 teeth and a 5th gear main shaft gear with 20 teeth with 28 splines which when installed will give me a..80 final drive .It also says for WC only .How do I verify that I will end up with a.80 ratio and will it fit on a non WC main shaft. this kit is from Competition Transmissions

Tim, If they say WC only it won't work. You need the set that was .73. It was also available in the 83/84 Mustang V8 T5 with 2.95 first. It was also available in the Camaro/Firebird V8 with the 2.95 first. To use the GM OD gears you would have to switch main shaft and slip yoke.I told Carl the tooth count for the two gears awhile back. Don't have those notes here. EDIT: found the tooth count for NWC .73 OD gears: 31 drive and 55 driven.



Edited 2 time(s). Last edit at 09/25/2018 04:59PM by mgb260.

Hi Jim. Thanks for responding. First of all I must say I have the T5 trans in my TR2 now and it works fine except when I change from fourth at 3000 rpm to fifth it drops to 2000 rpms and makes the 2.2 litre 4 sluggish to get more revs. It has a custom driveshaft for the Ford T5 so I don;t want to change that.Is it possible to change the main shaft to a WC one along with the two fifth gears?I'm worried that the NWC .73 gears may also be too tall also and the .80 ratio would put me at 2400 rpms in fifth with enough torque to rev better up to 65 or 70 miles an hour cruising speed.Thanks Tim

Tim, I don't know if the WC main shaft will swap. Call Modern Driveline and ask. What rear ratio do you have? You could go lower (higher numerically) or to a lower diameter tire. Or build your motor for more power.

Tim, Two places to look for information are: Pro-ForcePerformance.com for the history of the T5, and 5speeds.com
for videos explaining details of the T5.
From what I find, the 2.95 first gear unit has options of 31T/55T for a .72 o.d., and 33T/53T for a .80 o.d. I have not found
the 33T/53T set, and one place lists them as no longer available.
Changing the two gears is a little involved, the counter gear comes off with removal of a snap ring, but the mainshaft gear usually requires a press.
The mainshaft has to be removed in order to press the gear off and the new one on, which leads to "well, I might as well" regarding synchro, bearings and
seals. Pretty soon you are talking replacement cost. I desperately wanted to change my 3.35 first trans to 2.95, and that requires the counter gear, and
the three forward gears plus the two overdrive gears. So, I fixed the oil leak, replaced the input shaft seal and decided to cuss it when the first gear seems
too low. (I have a V8)
You will see that the o.d. gear choices result in a different overdrive ratio when using the 3.35 gears as the input/counter tooth count is different. If I had changes to a 2.95 input/counter gears with the associated forward gears, my overdrive would have been .59, which is really tall.
Dennis

Hi Jim. I suspect the main shafts are not interchangeable since the 93 WC trans has bearings and the 84 NWC doesn't. I will call Modern Driveline. The rear ratio on TR's is 3.7 No options there and then it changes all the trans gear ratios if you go to smaller tires. Hi Dennis Thanks for helping out. . I guess the only way to go is to find a93 T5 with the 295 first gear and then tear it down and install the .80 kit . Put it in the car and sell the 83 NWC to recoup some costs . Still wondering if the .73 gear set would be too tall ? Would maybe be ok in TR6 with more torque available with 2,5 litre. And I thought this would be easy because of all the gear ratios available . Thanks again guys Almost forgot tosay in the ID tag listings of T5's there is a mystery Ford Wc trans number 1352 225 which has a 292 first gear and a .80 fifth gear which is the very trans I need. but it has no listing of what car it was in. How would one find out the answer to that ? The plot thickens

It is probably aftermarket, Ford Racing,Tremec etc. Besides the 83/84 NWC I think all other Ford T5's had the 3.35 first. Datsun/Nissan also used the T5 in some 280ZX and 300Z cars. I believe it was Ford pattern with different input shaft/splines. 81-83 had 3.5 first. 84-86 had 3.35 first.



Edited 2 time(s). Last edit at 09/28/2018 06:06PM by mgb260.

"The rear ratio on TR's is 3.7 No options there..."

The confusing thing about saying TR is that there are so many different models of TR.

We have two different rearend ratios for our TR6 race car.

RE: TR gears...

Richard Good-something-or-other (forgot his last name) sells bits to swap to a Nissan R200S differential. A few gear choices there including 3.54 and 3.31.



Edited 1 time(s). Last edit at 09/29/2018 06:32PM by rficalora.

Richard Good of GoodParts specializes in TR6.

[www.goodparts.com]

Hi Carl.I always thought Triumphs TR2 to TR6 ran a 3.7 gear. What ratios are you running in your race car?Changing the rear end changes all the gears in the trans and I like all of them now very nicely except for the too tall .63 fifth so I'm sticking with that . I'll run it as a four speed untill I can build up a WC trans with the .80 over drive.Am I correct in calculating that when I shift at 3000 rpm in fourth that I will end up at 2400 rpm in fifth?That is what I have to know.

We have a 3.45 in the TR6 race car.

I have been using a T-5 with a .63 5th gear for 17.5 years. Works great with the MGB stock 3.9 rearend. ;)

Hi Carl .That's interesting.I had a friend of mine drive my TR2 yesterday and after three or four miles he said he thought the tachometer was reading high . At 3000 in 4th gear he thought it did not feel like 60 miles per hour.Ive been thinking all day what if I'm shifting at 3000 and dropping to 2000 in fifth and really i'm at1600 or 1800 in fifth. No wonder the car is lugging. I am going to have to get a precise measurement of my rpms with another independant tach. Will keep you informed

I believe that the USA carb version of the TR6 was 3.7 & that the EFI UK version was 3.45. I don't think the 3.45 was ever offered as OEM in the USA.

The genuine 0.8 gearset is no longer available from Tremec, any that come on the market make very high prices. The 0.8 ratios that are currently for sale are after market ones with larger teeth, this has the advantage of being stronger but the disadvantage of being noisier and the need to grind a small amount from the tailhousing to give clearance for the slightly larger gears. The original 0.8 was fitted to the Sierra Cosworth and some TVR's but was a little weak and often broke up when being removed from the shaft. This is of course no help in telling if they will fit a NWC T5

Hello Phillip. That is kind of nice to know. I'm going to get my tachometer problem sorted out and then see if i can use the.73 ratio gears in the 83 NWC trans so I don't have to buy another trans etc.

Hello Tim
I found the info that I was looking for here [www.5speeds.com] It shows exactly where you need to remove some metal. It also states that in a GM T5 you need to fit the Ford tailshaft and change the driveshaft yoke as well.
As you can see this gearset is not cheap.

5speeds.com state near the top of the page "Other companies have manufactured gearsets based on this very design". I did see on the USA Ebay several vendors selling a similar (same?) set for about $120
I would be interested to know if these "cheap" 0.8 gearsets are of a similar quality to the 5speeds.com ones.
Let us know how you get on.
Philip

Thanks Phillip. I will check out the info and keep you informed. Getting tach accuracy done first.

Got the tach checked out by hooking up a MGB electric tach and running the motor. At 2000 rpm on the electric one the TR2 tach read 1900. At 3000 electric the TR2 read 2900 so that was that.Took the car out yesterday and shifted into 5th at higher speeds At 3500 rpms in 4th the rpms in 5th were 2500 and not enough power to run it Pretty much same at 4000 in 4th .down to 3000 in 5th and some acceleration in 5th Since I want to use 5th at between 60 and 70 mph the .63 ratio is useless at any speed.Will have to figure out mathematically what the .73 ratio will do for me. Any info on that available? Tim

Quote:

.Will have to figure out mathematically what the .73 ratio will do for me. Any info on that available?

Sure.

[forum.britishv8.org]