f20 or f28 gearboxes

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joe cavalier sri
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f20 or f28 gearboxes

Post by joe cavalier sri »

Hi as you all are aware I'm going turbo but still haven't made my mind up yet which turbo either c20let or saab b204 but it will be one of the two ? :scratch
Now my question is after reading a few people saying f28's don't like tork and they don't like abuse like the f20 and that f20 is the best with the f18wr 5th gear conversion done can take the tork which I already have the f20 with f18wr conversion done on my c20xe all ready.
So which one would you all say is the best choice before I go spending money I want about 380bph out of the engine I buy or tune up to but It will be either the c20let or the saab b204 engine I choose many thanks Joe :thumb
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Robsey
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Re: f20 or f28 gearboxes

Post by Robsey »

Hmm torque eh..

You will find that the number in the gearbox code is the torque rating...
So F28 = 280 lb ft torque rating.
F20 = only 200lb ft torque.

So there lies the answer.
I am sure that most B204 / B207 conversions that I have read about use the F28 box.
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btcctroy
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Re: f20 or f28 gearboxes

Post by btcctroy »

F28 all day.
380 bhp looking forward to seeing how you get this.
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humbucker
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Re: f20 or f28 gearboxes

Post by humbucker »

Why don't you use the Saab gearbox? That's what Kirk has done with his Sri. Built for the job.
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TurboDan
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Re: f20 or f28 gearboxes

Post by TurboDan »

F28's dont like tourque? Where do you get your info ffs
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Robsey
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Re: f20 or f28 gearboxes

Post by Robsey »

I can guarantee Joe that the F28 would have much fewer issues than the F20.

This is confirmed if you have access to GlobalTIS, TIS2Web, TIS2000, EPC 3 & 4 (Technical Info section).

So whoever told you otherwise does not have a clue what they are talking about.
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btcctroy
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Re: f20 or f28 gearboxes

Post by btcctroy »

Buy an sccr with dog engagement.
Fit in with your rediculous budget
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joe cavalier sri
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Re: f20 or f28 gearboxes

Post by joe cavalier sri »

If I use f28 I mite get one of these to put power down but if I go saab b204 then use the saab box

https://shop.quaife.co.uk/opel-astra-f1 ... fferential
Desy221
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Re: f20 or f28 gearboxes

Post by Desy221 »

Hello! I am now also interested in this issue. I can not find the answer.
Microsoft Corporation customer service phone number
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Robsey
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Re: f20 or f28 gearboxes

Post by Robsey »

Don't worry - Joe never worked out the answer either.

It depends what you want to do with the car. From memory, Joe wanted to be the fastest Cavalier in Rotherham, so that he could race round his local estate quicker than his friends.

The answers are there though.

It makes sense to use an F28 in a Cav as this is the highest rated box used in the Cav range.
It was a regularly used unit on the V6 power units.

As for the Saab b204 engine units.
The Vauxhall f28 box will mate up to it quite easily.
You may have minor issues with mounts if you use a Saab box in the Cav engine bay.

And no doubt, any exhaust will need to be modified or custom made.
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Cavalier342
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Re: f20 or f28 gearboxes

Post by Cavalier342 »

Robsey wrote:Don't worry - Joe never worked out the answer either.

From memory, Joe wanted to be the fastest Cavalier in Rotherham, so that he could race round his local estate quicker than his friends.


:lol: :lol: :lol: :lol:

Then appear live on the next series of Police Interceptors or Road Wars :D
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