4 speed crossmember.

[Mad4slalom]

Hi all , anyone fitted or know anything about the removable trans crossmember kits available from American powertrain. I think ecklers sell /sold them . Wondering if this can be done in situ. My box has to come out so seems a good modification whilst in there.

 

[James Vette]

Is your corvette bridgehampton blue and is it original paint?

 

[Corvette]

It seems a lot of work when all you have to do is pull the box back whilst turning it 1/4 turn.

 

[Forrest Gump]

Hi all , anyone fitted or know anything about the removable trans crossmember kits available from American powertrain. I think ecklers sell /sold them . Wondering if this can be done in situ. My box has to come out so seems a good modification whilst in there.

Wouldn't you only do that if you were converting from manual box to automatic box, where the crossmember is detachable to enable auto box removal?
It is not massively difficult to get a manual box in and out with the fixed crossmember.

 

[Mad4slalom]

Wouldn't you only do that if you were converting from manual box to automatic box, where the crossmember is detachable to enable auto box removal?
It is not massively difficult to get a manual box in and out with the fixed crossmember.

I am not sure , I have read good and not so good reports of how tricky it can be to remove box. Seems logical that a removable crossmember is the easiest route. Will google it some more . Someone must have figured it a benefit to go to the trouble of designing and producing a kit

 

[Mad4slalom]

It seems a lot of work when all you have to do is pull the box back whilst turning it 1/4 turn.

Some say bellhousing off some say bellhousing left on , is there a factory recommended step by step procedure?

 

[Mad4slalom]

Is your corvette bridgehampton blue and is it original paint?

It is very close to bridgehampton blue, it is actually 2002

Is your corvette bridgehampton blue and is it original paint?

it is very close to 1972 bridgehampton blue, it is actually 2002 electron blue and not original as the car was white from the factory then bridgehampton or targa blue I think before being off the road for 20 years.

 

[Oneball]

I can never really see how a crossmember attached with two bolts can maintain the rigidity of one that is welded in place.

 

[Mad4slalom]

I can never really see how a crossmember attached with two bolts can maintain the rigidity of one that is welded in place.

Maybe not but loads of crossmembers are removable with no issues . Look at how many modern cars have a removable crossmember that supports not only the gearbox but the engine and front suspension as well. . Cant see why, if GM did it for the auto box ,(that is more likely to last its liftime in the vehicle ) they didnt do it for the manual that is going to need to come out for clutch renewal st some time.
seems a lack of foresight to me .
Reminds me back in the day I fabricated a gearbox crossmember for my 55split window morris minor from part of a tubular trampoline leg to support the 289 ford v8 and C4 auto box . Bolted between the rails of the jago pop chassis I used under the moggy. Worked a treat

 

[Roscobbc]

Having had the manual engine/transmission combo on and off my BB more times than perhap a 'lady of the night' changes her drawers I can say that unless you are perhaps upgrading to an alternative manual transmission (and the new crossmember comes as a kit with the gearbox) then I don't really see any advantage.

 

[Chuffer]

I can never really see how a crossmember attached with two bolts can maintain the rigidity of one that is welded in place.

Judging by the quality of most of the welding on a C3 , double sided sticky tape would be as effective .

 

[stealthyflatfish]

I can never really see how a crossmember attached with two bolts can maintain the rigidity of one that is welded in place.

Two bolts at each end Oneball.
Just changed my clutch assembly on 5 speed tremec, crossmember out, prop off, four bolts to disconnect gearbox from scatter shield
( bellhousing ) disconnect Speedo cable, take gear knob off, drop gearbox out. Gota be easier than trying to get whole lot out in one go. Just my three penny's worth chaps.

 

[Oneball]

Ok 4 bolts. But my thinking is if there wasn’t an advantage to the welded crossmember Duntov wouldn’t have done it.

 

[Forrest Gump]

Two bolts at each end Oneball.
Just changed my clutch assembly on 5 speed tremec, crossmember out, prop off, four bolts to disconnect gearbox from scatter shield
( bellhousing ) disconnect Speedo cable, take gear knob off, drop gearbox out. Gota be easier than trying to get whole lot out in one go. Just my three penny's worth chaps.

Was your car originally an auto or have you converted it to a removable cross member?

 

[stealthyflatfish]

oneball, I did say it was just my three penny worth having not got a welded gearbox cross member, I don't know how fiddly it is to get a gearbox out with the cross member still in place, others have said it's easy anyway.
Perhaps in the early days of Corvette production it was cheaper to weld a cross member in, than to bolt one in ?
I think I'm correct in saying that from 1980 on they were bolted in anyway,
so why would a bolted in one (correctly) not be as strong as a welded in one? There are lots of companies in the States that sell bolt in conversations, you just have to make sure you get the right conversion kit for the type of of gearbox you have or are using.
Just saying.

 

[stealthyflatfish]

Was your car originally an auto or have you converted it to a removable cross member?

No Forrest it's always been a manual
from day one of manufacture, but the tremec conversion was done in the States, and it comes as a complete kit including the bolt in cross member.
About an 8000 dollar conversion at the time if I remember correctly. Also it has side pipes on which must make it easier clearances wise underneath, no exhaust pipes to get in the way. oh! it's a 71 BB by the way, and I believe the conversion was carried out in 2005 going by the serial numbers stamped on the gearbox.

 

[Oneball]

oneball, I did say it was just my three penny worth having not got a welded gearbox cross member, I don't know how fiddly it is to get a gearbox out with the cross member still in place, others have said it's easy anyway.
Perhaps in the early days of Corvette production it was cheaper to weld a cross member in, than to bolt one in ?
I think I'm correct in saying that from 1980 on they were bolted in anyway,
so why would a bolted in one (correctly) not be as strong as a welded in one? There are lots of companies in the States that sell bolt in conversations, you just have to make sure you get the right conversion kit for the type of of gearbox you have or are using.
Just saying.

sorry wasn’t meant to be argumentative just the reasoning that was going through my head.

 

[Forrest Gump]

No Forrest it's always been a manual
from day one of manufacture, but the tremec conversion was done in the States, and it comes as a complete kit including the bolt in cross member.
About an 8000 dollar conversion at the time if I remember correctly. Also it has side pipes on which must make it easier clearances wise underneath, no exhaust pipes to get in the way. oh! it's a 71 BB by the way, and I believe the conversion was carried out in 2005 going by the serial numbers stamped on the gearbox.

I see. Sounds like a great set-up you’ve got with your Vette

 

[stealthyflatfish]

sorry wasn’t meant to be argumentative just the reasoning that was going through my head.

Oneball, no offense taken, just two blokes having a discussion about mad4slaloms original question

 

[Mad4slalom]

Judging by the quality of most of the welding on a C3 , double sided sticky tape would be as effective .

Here is the one I found, pretty easy to fit as long as you can cut the old one out with the limited clearance between the top of the crossmember and the floor.. will certainly make box removal easier once fitted.