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Nivlek2525

4 to 5 speed conversation

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Help please.

I've read thought previous posts so I know this has been covered before but I'd really appreciate some details if anyone has them.

I'm looking at potential fitting a GTE cih engine in my manta possibly with carbs and a cam. I've also managed to source a 2.4 head but I don't know if I can use that yet.  Anyway,  my car would have originally had a 4 speed box so has the 4 speed tunnel. I know I can cut out the tunnel and install a 5 speed tunnel or modify my tunnel. However, I've read that the 5 speed box can be modified by shortening the linkage (or shortening something) so that the 5 speed will enter the car through the 4 speed hole. 

This is referred to on a number of posts but the detail either isn't there of the photos are gone.

So, can anyone tell me, preferably with a helpful pic or two, how to make a 5 speed work with a 4 speed tunnel.

Also, is the 2.4 head I've been offered of any valve to a 2.0 engine?

Many thanks all.

Kelvin.

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Posted (edited)

Think i remember reading if 5sp stick throw is shortened to fit 4sp hole, fifth gear can touch the radio, or is it first?, i remember seeing someone fit a 4sp stick to a five speed box. Another problem is finding a colour matched 5sp centre console. Another is 4sp gearbox mounts. Mont needs made up to hold 5sp box, or you need 2x 5sp mounts.

5sp mount are further back on shell, you can leave 4sp mounts in place.

As for 2.4 head to 2.0. Never seen it done, has to be a reason why. I would imagine valves issue. Compression maybe?

 Had a 2.0 gte with 2.2 carlton exhaust valves fitted, fit for a 2.0. Lively!

Ive a 1.6 4sp manta b, brilliant wee driving car. Never tried a 2.0 diff, maybe better for motorway cruise speed.

 

Edited by ®evo03
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Not sure on the GTE but i have fitted the 5 speed to my A series, you shorten the main selector rod and mounting for the gear stick and modify the gearbox cross member. no tunnel mods needed.

I have the box out of the car so can take pics of all the bits, you can get the mount from Thomas 

https://www.edelschmiede.com/shop/Damping-block-transmission-suspension-rear-5-speed-Getrag-240-265-cih-automatic

I fitted the old 4 speed stick to the 5 speed mount so it looks like it has a 4 speed, the throw is a lot shorted and shift is quicker.

 

I can get you some pics of the old selector shaft V the shortened one, you need someone who can weld it up properly or i think you can by the kit from some one on here, its up to you. Well worth fitting the 5 speed. Its tight getting it in and bolted on with the engine in!

 

From reading on the head i think the 2.4 head will be wrong for the 2.0, wrong compression and also you will need the 2.4 manifold as the ports are offset with the intake higher so your 2.0 wont fit (new gasket needed as well) better off getting the 2.0 fitted with bigger valves and ported rather than spending the money making the 2.4 fit.

Lots of info on here if you do a bit of searching.

https://www.opelgt.com/forums/forum.php

 

Not sure if i put any pics on the box on my blog? www,theopelproject.com

I can get some pics tomorrow night if you want.

 

Andy

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Posted (edited)
1 hour ago, ®evo03 said:

Think i remember reading if 5sp stick throw is shortened to fit 4sp hole, fifth gear can touch the radio, or is it first?, i remember seeing someone fit a 4sp stick to a five speed box. Another problem is finding a colour matched 5sp centre console. Another is 4sp gearbox mounts. Mont needs made up to hold 5sp box, or you need 2x 5sp mounts.

5sp mount are further back on shell, you can leave 4sp mounts in place.

As for 2.4 head to 2.0. Never seen it done, has to be a reason why. I would imagine valves issue. Compression maybe?

 Had a 2.0 gte with 2.2 carlton exhaust valves fitted, fit for a 2.0. Lively!

Ive a 1.6 4sp manta b, brilliant wee driving car. Never tried a 2.0 diff, maybe better for motorway cruise speed.

 

Thanks Evo

I have two 4 speed consoles and a 5 speed console. The 4 speed is black so won't match the interior but being black it might look ok. If not I'll maybe spray it?

Shame about the 2.4 head. I thought I'd heard they were better flowing heads so snapped it up. Not the end of the world. It has a nice alloy rocker cover which I might be able to use.

 

28 minutes ago, 611 said:

Not sure on the GTE but i have fitted the 5 speed to my A series, you shorten the main selector rod and mounting for the gear stick and modify the gearbox cross member. no tunnel mods needed.

I have the box out of the car so can take pics of all the bits, you can get the mount from Thomas 

https://www.edelschmiede.com/shop/Damping-block-transmission-suspension-rear-5-speed-Getrag-240-265-cih-automatic

I fitted the old 4 speed stick to the 5 speed mount so it looks like it has a 4 speed, the throw is a lot shorted and shift is quicker.

 

I can get you some pics of the old selector shaft V the shortened one, you need someone who can weld it up properly or i think you can by the kit from some one on here, its up to you. Well worth fitting the 5 speed. Its tight getting it in and bolted on with the engine in!

 

From reading on the head i think the 2.4 head will be wrong for the 2.0, wrong compression and also you will need the 2.4 manifold as the ports are offset with the intake higher so your 2.0 wont fit (new gasket needed as well) better off getting the 2.0 fitted with bigger valves and ported rather than spending the money making the 2.4 fit.

Lots of info on here if you do a bit of searching.

https://www.opelgt.com/forums/forum.php

 

Not sure if i put any pics on the box on my blog? www,theopelproject.com

I can get some pics tomorrow night if you want.

 

Andy

Andy

Thanks, this is exactly what I'm thinking about. If you could take a photo or two so I can work out what I need to do that would be great. I still need to source a 5 speed box but I have an engine and 5 speed propshaft sorted so I'm getting there. I'm just planning so I can roll straight on with the mechanical stuff once I'm finished with the structural repairs. I'll look at those links now.

Thanks again.

Kelvin

Edited by Nivlek2525

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They are better flowing but from what i have read on opel gt forum wont work great with the 2.0l. 

This is the inlet and exhaust on the 2.4, inlets much higher.

spacer.png

 

If its one of these rockers it will fit nicely 🙂

spacer.png

Had a couple of issues using the cork gasket as you cant tighten the alloy cover down as much as you can with the steel one. Got  rubber gasket that seals perfect. Can find the link if it helps.

 

Andy

No problem, i will get pics tomorrow and post up.

Best to connect the engine and box and drop the front sub frame, lift the body up and roll in the front sub frame with engine and box on, super simple otherwise even on a ramp its a bugger to get the box in and the top bolts tightened up with the  engine in. Been there, done it, cursed a lots and learnt the hard way 🙂

 

Andy

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Posted (edited)
20 hours ago, 611 said:

They are better flowing but from what i have read on opel gt forum wont work great with the 2.0l. 

This is the inlet and exhaust on the 2.4, inlets much higher.

spacer.png

 

If its one of these rockers it will fit nicely 🙂

spacer.png

Had a couple of issues using the cork gasket as you cant tighten the alloy cover down as much as you can with the steel one. Got  rubber gasket that seals perfect. Can find the link if it helps.

 

Andy

No problem, i will get pics tomorrow and post up.

Best to connect the engine and box and drop the front sub frame, lift the body up and roll in the front sub frame with engine and box on, super simple otherwise even on a ramp its a bugger to get the box in and the top bolts tightened up with the  engine in. Been there, done it, cursed a lots and learnt the hard way 🙂

 

Andy

Thanks Andy,

The subframe is off now as I'm working my way around welding up the underneath. In fact the car is currently upside down so I'll do as you suggest. 

I was originally going to fit a bigger engine as my car was just a shell when I bought it but I've read lots about what you can do with the cih engine and thought I'd give that a go. A GTE engine came up and there was a 2.4 head next to it. The lad told me it wouldn't work, but of course I knew better...

Rocker cover isn't the same as that unfortunately. It's marked up 2.4 on the top but I thought I could maybe remove that and just make it plain.

Really appreciate any guidance on the gearbox. The shell is in good shape and I'd rather not cut I to the tunnel is I done need to. Also I quite like the idea of it looking like a 4 speed.

If it's just the inlet that's nighter and I run carbs, would that work do you think? Would I still have a compression issue?

Thanks again.

Edited by Nivlek2525

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If you contact Paul Newport he should be able to walk you through the gear stick conversion

 

Andy

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2 hours ago, Nivlek2525 said:

Thanks Andy,

The subframe is off now as I'm working my way around welding up the underneath. In fact the car is currently upside down so I'll do as you suggest. 

I was originally going to fit a bigger engine as my car was just a shell when I bought it but I've read lots about what you can do with the cih engine and thought I'd give that a go. A GTE engine came up and there was a 2.4 head next to it. The lad told me it wouldn't work, but of course I knew better...

Rocker cover isn't the same as that unfortunately. It's marked up 2.4 on the top but I thought I could maybe remove that and just make it plain.

Really appreciate any guidance on the gearbox. The shell is in good shape and I'd rather not cut I to the tunnel is I done need to. Also I quite like the idea of it looking like a 4 speed.

If it's just the inlet that's nighter and I run carbs, would that work do you think? Would I still have a compression issue?

Thanks again.

Personally i would flog the 2.4 head and spend the money on the 2.0l. The opel gt forum have lost of info on the 2.4 and most say it wont work. I had a 1.9, bored out to a 2.1, big valve head, ported etc... drove nice, think i could have got a bit more out of it but when i went to rebuild it there was a crack by the valve guide and i could have had it fixed but i had read how good the 2.4 was on the opel forum. So i bought one, worst mistake i could have made, lots of bits are different, pistons cost a fortune, i have spent so much time and money on this bloody engine and its still causing me issues. I should have got another 2.0l head and spent the money on getting that fully sorted, better cam etc. (i might even end up doing that!)

 

Got back from work late and a bit dark to take good pics, i have the bits ready to take pics of so will get it all done tomorrow as have the afternoon off.

Andy

2.4 rocker cover looks nice, the one on mine was very corroded so didnt bother but cleaned up they look nice, you could probably get the 2.4 ally welded and sanded flat.

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Right, managed to get those pics for you. I hope if gives you an idea of the setup. Mine is on an A series so you might need to get the box in place and measure as im not sure if the GTE stick is in the same place and the pics of the gearbox mount might not be 100% right with my adaptor plate on as it was over a year ago that i took the box out!!

As you can see from the stick i measured exactly where the old 4 speed sat so then with the 5 speed stick in place after i could work out the height to cut it off and weld the old one in place so it sits exactly how it did with the 4 speed box. Only word of warning if you do that is dont leave it with the garage to move when they do the MOT as even though i told them it was a 5 speed and how to get it into reverse one of the twats decided to not listen and jam it in gear but trying to select reverse from the diagram on the gear knob! and he was a knob 🙂

Got a nice one from opel gt source that is the same as the old A series 4 speed with the 5 speed pattern on top!

popped the pics on the blog.

http://www.theopelproject.com/?p=1742

i might make it into a proper post later as going to trial fit the box this weekend so might add some proper pics of the cross member setup.

 

Andy

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23 hours ago, 611 said:

Right, managed to get those pics for you. I hope if gives you an idea of the setup. Mine is on an A series so you might need to get the box in place and measure as im not sure if the GTE stick is in the same place and the pics of the gearbox mount might not be 100% right with my adaptor plate on as it was over a year ago that i took the box out!!

As you can see from the stick i measured exactly where the old 4 speed sat so then with the 5 speed stick in place after i could work out the height to cut it off and weld the old one in place so it sits exactly how it did with the 4 speed box. Only word of warning if you do that is dont leave it with the garage to move when they do the MOT as even though i told them it was a 5 speed and how to get it into reverse one of the twats decided to not listen and jam it in gear but trying to select reverse from the diagram on the gear knob! and he was a knob 🙂

Got a nice one from opel gt source that is the same as the old A series 4 speed with the 5 speed pattern on top!

popped the pics on the blog.

http://www.theopelproject.com/?p=1742

i might make it into a proper post later as going to trial fit the box this weekend so might add some proper pics of the cross member setup.

 

Andy

Many thanks Andy.

I read through your blog the other night. Great effort. 

I've also looked at the pictures which I think makes sense. I need to source a 5 speed box and do some measuring but I really appreciate you confirming that it can be done which is that main thing I was after.

I'd love to read a full write up if you get around to doing it.

Thanks again

K

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Hi Kelvin

Im glad the pics are helpful. I also have a diagram of the Getrag gearbox under workshop section in case you need it when you get the box. When i got mine the main bearing was noisy which i changed and while i was there i stripped the box and replaced any bits i could get that were new so the diagram is helpful.

I set the blog up initially to record the progress but i found that as i was restoring things it was hard to find pics of stuff so i started writing up things and as the project has been over a very long time it was some times a handy reminder 🙂 and hopefully some of the modifications might help others.

When i get mine in this weekend i will be taking pics etc.. and doing a write up as i have a hydraulic clutch im fitting so i need to record this as well some hopefully by the time you get your box all the info will be on there to help you.

 

Just shout if you need any more info when you get the box.

Im off to write up the problems caused by aftermarket timing chain guide parts!! as i think i have figure out my issue with the engine!

 

Andy

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