Mike1985

Hey all, just a quick question for you guys. I have an 85 with the 700r4 automatic tranny and Im thinking of getting the b&m shifter ratchet shifter. Wouk putting it into 1st and shifting through the gears be bad for my transmition? I've seen mixed thoughts on this online so I figured I'd ask it on here. Thanks for any opinions!

John A. Marker

Just an opinion. The trans can shift better than you. If you want to tighten things up, then add a shift kit into the transmission and upgrade the converter to a higher stall. The stock stall is about 1400 RPM. If you go to a 2400 stall, it will still be drivable on the street but get you to the higher RPM torque range. If you are running the 1/4 mile then leave it in D not over drive. IF your running autocross then put in in 2 and leave it there.

My past experience has shown me that these (700R4) last about 100,000 miles or so with normal driving. More if your easy on them. They can be upgraded with heavy duty parts.

JD Shredds

I wouldn't be concerned about killing your trans upshifting on acceleration (its designed to work that way for a reason), but I wouldn't say you're doing it any favors. Keep in mind if you're going for speed, like stated above, the transmission will shift better (faster and smoother transition) than if you do it manually.

gerardvg

Hi

The best gear is Drive, the TPI engines have their peak torque before 5,000 rpm. If you want to redline it before every gear change you tend to go slower over a quarter mile, i have found D the best in my experience with turbo 700 transmissions.

Short shifting works best shift at around 4,500-5,000 rpm, (unless you have a mini ram intake then you can take advantage of 6,000 rpm shifts)

Take her to a drag strip and practice, you will find drive is the best gear.

You can adjust the shift points and firm it up by adjusting the TV cable tighter, if that is not to your liking a shift kit is the way to go.

If you are putting extra hp though the transmission a heavy duty rebuild, an extra oil cooler will lengthen their life.
A lot of horsepower and you are going to go through these transmissions quickly, transmission builders may say good for 600 hp but that is just wishfull thinking.

I have had my 85 for around 20 years, and have blown 4 turbo 700 transmissions, the last two were expensive extreeme duty builds.
When you put more h/p and hard launches though these they do not last very long.

John A. Marker

with gerardvg.

Mike1985

Correct me if I'm wrong, but I thought D without square around it was 3rd gear? Or is that just turning off overdrive?

gerardvg

OD =1,2,3,4. Drive =1,2,3 gears only.
Normal driving leave it in overdrive, drive (with overdrive inhibited) is for mountains if you do not want it shifting in and out of overdrive at certain speeds on uneven terrain.

It doesnt really matter when the pedal is pushed flat to the floor will inhibit the shift to overdrive, which is a real pain having to lift the foot to allow it to shift into overdrive. (at around 200kmh third gear will hit the wall with 3.07 gears, "120 mph" then lift the foot and when it shifts into overdrive you can slowly depress the pedal and go to 150 mph). Which she did when i first got her stock standard, some 20 years ago.

I hate that overdrive inhibitor function, found that out at a airport runway hired for car clubs to see how fast they could drive their cars.
It must be a safety feature to prolong the transmission life....

Some say corvette turbo 700 trans will shift into overdrive when accelerating flat out, all 4 previous transmissions never did.

Mike1985

Thank you so much!

LAddams

Had that ratchet shifter in my chevelle years ago. Like the others said drag racing your better off setting up the trans and letting it do its thing. But i can tell you, it was really a lot of fun to crank that baby all the way back,load it up then slam forward 1st pull back Slam! forward second etc. Really a blast.

Cliff Harris

Mine did after I massaged the valve in the governor. Sanded off the sharp edges and it now shifts into OD at WOT.

Lloyd Smale

put one in my old iroc. Don't know if it made me faster but it was fun playing with and I guess that's what these cars are best at doing as there not really all that competive on the strip anymore anyway.

crowz

Not a fan of the b&m ratchet shifters. Ive had a few and its kind of what everyone uses in the real drag built cars and trucks around here.

The T handle version looks awesome in a trans am for instance and probably could be setup fine in a vette. The problem is they are not reliable for a street car that's driven all that much. The best I can describe what happens with age is the frame wears out and the thing starts jamming up. I went thru about 5 of them in the trans am for instance. Even the people around here that only run the drag cars on the track on Saturdays have them fail eventually. The boxed body ones with the ball shifter seem to hold up the best. I think they are called quick silver or something. But even those wear out.

So nice while it works but the hassle of it messing up gets old fast for a daily driver. My wife had a real knack for jamming the trans am's shifter and calling me to come get it out of park for her or she would come home and it would be stuck in drive.

Also I agree with the post above on a good shiftkit and leaving it in drive being the best choice for shifting.

arbee

Why are you still telling people to wreck their equipment? I provided you with two links from reputable companies that clearly state the sharp edges on a hydraulic valve are there for a reason.

MaxDaemon

I think Cliff was just providing information. He wasn't advocating anyone go out and do it themselves. We are all adults here, we can make our own decisions based on what we want. Personally, I want as much information as I can get ..

MaxDaemon

Now that the conversation has died down to bickering I feel I can ask a question without hijacking the thread much.

My '84 came with a "shift kit". Being a newbie to all things Corvette (and mods for that matter) I was wondering what that entailed? I was hoping it meant that when they put the shift kit in, it meant that also rebuilt the transmission while they were at it. Seemed to me it would be logical that if you were modding the trans, you'd go through the whole thing. Like replacing all the light bulbs in the instrument panel as long as you'd gone through the pain of taking it all apart anyhow.

Obviously you can't tell me if they DID go through the whole thing, but I was hoping you could give me the logical answer.

Thanks!

Churchkey

If performance & fun factor are the goal suggest installing the ratchet + a manual valve body.

arbee

I beg to differ. Below is a direct cut and paste from a different post he made on December 6.

"I suggest smoothing the sharp edges of the valves with emery cloth so they move more easily. They tend to bind in the valve body otherwise. That's why they are so hard to get out. "

People come to these sites to get help on problems with their car. Often, they are trying to save some hard earned money. Giving false information loosely does a disservice to these people and can cause hundreds of more dollars in damage.

crowz

A shift kit is normally just a valve body rebuild for the most part. It can range from something as simple as removing the valve body and adding or removing check ***** to new springs, valves and even drilling passages larger in the valve body. What kit you go with determines how much is done. So basically a shift kit is something that's easy to do normally and requires nothing more than dropping the pan and removing the valve body (plate on the bottom of the trans) tinkering with it and putting it back.

So no its not a rebuild or anything major.

ghoastrider1

never seen an auto miss a shift.

MaxDaemon

Ok. So I got an oil change and pan gasket and probably filters, but that's likely about it? Still not a bad deal - better than having 80k mile oil in her!