BBC, which Transmission is the best?

[betzjr66]

Hello all,
I have a BBC that I plan on running in a Cobray. I decided to go with a Richmond 5-speed partly because I got a great deal, but also because I was able to keep the stock 3.08 gears in the rear (saves $$$ on a gear swap)with this trans and have it act like a 3.73 geared car with a .8 overdrive. What is everyones transmission preference? Anyone else using a Richmond?

[Lightingrod]

How much torque?

Al

[vettestr]

Hey betzjr66,
Are you running the Street Richmond tranny? Here is a good info site with RPM's listed at different gear selected (1 to 5th) and tire size listed. I think the Street version is rated at 600 for torque so you should be fine, especially with a light car.
http://www.5speedtransmissions.com/5sp_comparison.html

[RICK LAKE]

betzjr66 I have a couple of questions. What is the power output on your BBC? What tires are you running, Street autocross, slicks? This question is most important, what are you going to do with the car? Street driving and Shows? autocross and roadracing, Drag racing, alittle of all this? Here is the issues. You have not said which trans you have. The one that has been out for the last 15+years has a tork and HP rating of 450HP and 450ft pounds of torque. For normal street driving with street tires this trans SHOULD be no problem and holdup. The gears inside are cut a 22 degrees to keep the trans quiet and keep noise down. The new Super street trans has straight cut gears and a 600 HP and torque rating. I'm sure that you BBC is maken 500+ ft of tork. I run 2 different transmissions. I have a 6spd Richmond for street with the overdrive. The first gear is 3.25, what a waste with 3.31 rearend gears I never use it. It's 1" longer for the trans mount location. It only has a 450/450 rating. I don't beat on this trans and ONLY run BFG street tires because they have poor traction on the street over other tires. I race with a G-Force 5 spd. The externals are the same as a richmond 5 spd but this trans is good for 1000 HP and torque. It's a semiclutchless 5 spd. It is also about twice the price as the cheaper Richmond 5 spd. I am looking at the superstreet 5 spd with the 2.87 first gear and overdrive 5th gear. This is the one that would BEST fit you over all needs. IMO You will not hear the straight gears when driving if you have side pipes. I like and run both transmissions in my car, I also KNOW there limitations. Rick L.

[betzjr66]

The trans that I got is the 4+1. I believe that it is rated at 450 lbs. I only plan on using street tires on this car and driving it for fun and to local shows. There is a possibility that I take this car to the local drag strip, if so, I would probably run a drag radial instead of a full slick and keep my fingers crossed. I believe that the wheels will break loose before the trans. breaks. the car will weigh under 2500 lbs. with the big block when it is completed. I am thinking of a 10 in. wide rim on the back with a 285/40 tire.

[RICK LAKE]

betzjr66 The problem is wheel hop that does most the damage to the trans, clutch and rearend IMO. You you have to do is come out of the hole easy and then you can get into it. The gain and lose of traction is what breaks more parts than anything else. Leave the starting line at 1,200 rpms, If the car squats and leaves, raise the rpm's another 100 rpm, When you start to spin you tires off the starting line back down 100 and stay there. Make sure that both rear tires have the same pressure in them. If the rear shocks are adjustable, turn down the dampeners to softer so the car will that weight transfers, the rear of the car will go down and leave. This puts more weight on the rear tires to hold the track surface. If you get wheel hop off the line, and the whole car shakes, GET THE HELL OUT OF THE GAS. Don't try to quick shift the trans too fast. I have seen some guys go from 2nd to 5th more times than I can count ( 7 ) . I race with 2nd gear and stay out of first, the shift is to quick, and in 2nd it slows down some of the power shock to the rear tires. Don't worry about the other car, If you are ahead great, if not keep 1/2 an eye on him for keeping control of his car. If that little voice starts talking in your ear, listen and get out of the gas. Save the car for next run. That's the best info I have to give you. Don't run fastern than 12.00 They will throw you off the track for safety issues. Been there had this happen. OPPPSSS. Have fun and be careful Rick L.

[vettestr]

Rick's description of the launch as a squat and squirt motion was very accurate. With the torque of a big block and the low car weight many people would be happily surprised with the launch. Because the Cobray is over 1000 pounds lighter than a stock 68 to 82 Corvette the handling is greatly improved.

In most cases if wheel hop is encountered on our car the shocks need to be firmer and /or the RPM lowered. The driver can feel the car squat and begin it's launch but you can throw that run away if you roll power on so fast it blows the tires off the car. Aftermarket companies like VBP now have a Dual Mount Rear Suspension set up that helps to tame the torque. With big HP/torque numbers you can boil the tires at will but it will tell you it is coming if you listen. If not hang on.

[betzjr66]

Jeff, This is Mike from California. I have the dual mount spring that you are refering to. I believe that I sent you some pics of the set-up a few months ago. I have set the spring farthest to the inside of the car which my understanding is will lengthen the distance of the fulcrum to wheel and give me the softest spring rate. I thought I would start here, play with launch rpm, then try adjusting the spring rate. Sound like I am on the right track? I also have a Centerforce Dual Friction clutch which I believe is significantly stronger than stock, Not sure if this will have too much effect on trans. life with the traction issues we are talking about. By the way, I just went to the 3 day show at Pismo Beach in California, It was Fantastic!

[vettestr]

Hey Mike,
I would love to have checked out the show at Pismo. I have not been myself but have heard from a few friends it is a very nice show.

The dual mount spring set up you are running is the ticket. I think you would be better off setting her up 1 more notch in the heavier direction ( #2 hole). You can run the current setting and change after some seat time and shake down miles as it is very easy to change.

I don't think the heavier clamping force clutch is an issue for the tranny as in the real world the clutch is only a problem if slipping and the rest of the time more of an on / off sw. A real aggressive disc material can be touch n go but all is good with your choice. If running a SB you may want a rear end ratio closer to the high 3's or even a 4:11 for play time but the BB will not care and loves your current ratio. It is Play Time !! Jeff C

PS. I will check but do not remember seeing any photos recently???

[betzjr66]

Hey Jeff, Just added a pic of the dual mount rear spring to my gallery. It was quite a while ago when I sent you the photo in an e-mail to cobras n vettes concerning the front springs that I bought. You had stated that the rear spring rate would affect the front spring rate so I sent you a reply with my adjustable rear spring photo and you sent the front springs accordingly, Thanks Jeff

[1Cobrat]

I'm running the street richmond (4+1) behind a 550+hp 427 BBC with a C4 Dana 36 rear end. As others have mentioned you need to go easy on the take-off. I've found that once you get rolling you need to feel where your torque kicks in and play with it. Mine is about 3,900 RPM. The tires start to spin when I'm on it hard. I can see not messing with first gear. You really get through it fast. However, I've noticed that the Richmond shifts hard. I have blown many of shift and have gotten the trany stuck between gears a few times. I getting the hang of it but it is tight. 2nd to 3rd is my biggest problem. I may need more clutch release. Haven't tried that yet. All in all I'm happy with the trans. . . .

[RICK LAKE]

1Cobrat You are not the first to have the same problem. I went through this in 97 with the new 6spd that came to market. My car wouldn't shift over 2,800 rpms with clutch, I could bang it into gears by coasting, letting the rpm's drop and slide into the next gear. I don't know what clutch you have but, IMO the centerforce gold SUCKS. Centerforce was call 6 times and NOBODY in TECH know what they are talking about. I sent the trans back to Richmond thinking it was a trans or shifter problem. They call and said no problem. I explained the issue and they had it put in someones car and driven for a couple of days, Again no problem. It was sent back with the shifter setup by them. Put the trans in the car and the same problem. Call Centerforce and went round and round about those sliding wieghts and how they work. Centeforce SWORE it was the TRANS. I was not into racing but was heading in that direction. So I got a new G-Force clutchless 5 spd and 2 shifters for the trans. $6,500.00 dollars later and 2 weeks the new trans was in the car. Same shifting problem over 2,800 RPM. The bottom line is the weights are locking up the disc, unless you have a heavy TOB and strong fork, you will bend the fork and the clutch will not RELEASE. I pulled the trans and ripped off the weights, reinstalled the 5 spd and no trouble shifting at 6,000 rpms, put 6spd in car and no shifting problem at 6,000 rpms. PI$$OFF person. I have been racing with both transmissions since 98. After running roadracing, my trans starts to get stiff shifting. I run 85W-90 synthestic. I gets very hot in the tunnel araea from no way to remove the heat from the inner brakes and heat from the motor. Was given 3 ideas, Change the fluid to Amsoil rearend lube, Go to ATF fluids( all the new cars are running ATF instead of heavy gear fluids ), or add a trans cooler and pump assembly to the car to keep down the trans fluid temp. I have double reflective tape on the tunnel for heat inside the car and my headers are rapped, and inner Jag brakes get hot from racing. Richmond sells GL-6 that is 75W-140. This almost the same stuff as what I am running. I am looking at the cooler idea. The ATF bothers me, I will need to call Richmond on this before trying it. My Trans binds up after 15-20 minutes of racing. Good Luck. I will reply after talking to Richmond again Rick L.

[vettestr]

Hey All,
When the Center force P plate assembly was new to the market I was working in a machine shop and running the balancer. I found the weights made it impossible to get a repeatable balance as they moved around a bit. This was many years ago and sure a zillion have been sold since then and are still being used.

I am a big supporter of additives and like Lucas myself and synthetic as well. If you are pushing a component out of the average use it makes sense to me to use lubricants with higher ratings. Heat has a huge impact on most things but I think our Cobray breaths or cools better than many stock body cars including the Vette.

Rick, what is the tranny in that is getting hot? Let us know what direction you choose and how it works.

[Snakebit]

Richmond road race 5 speed. 3.28 1st with 3.08 rear

[1Cobrat]

I'm just running a cForce 384148 disc with a heavy duty Hayes diaphram cover and a McLoed 1300 series TOB. Nothing special. Am also using the RedLine Synthetic that Richmond recommends. The shifter (Hurst) seems a little loose all the way around. I may get a different shifter that has more positive heim based shifter fork connectors. Something my Nascar buddy runs and I forget the name. I need to spend some more time diagnosing and testing various work arounds.