My C20LET conversion thread

Update post #38






Instead of making lots of separate threads I thought it would be better to keep all questions in one place.

I will update as I progress.

1- What fuel pump? My car had a XE and an external GM pump, no idea what its capable of.

I was thinking Walbro 255?

2- The engine is running 291 BHP (apparently), is this intercooler good enough? LINK

3- I'm using F28 with flat type flywheel, I done some research and people are saying I need F28 clutch plate and F20 pressure plate. So I'm going to to buy a new F28 clutch kit and a second hand pressure plate, is this a good idea?

One more thing, what clutch do you recommend?

4- I might get a LSD for the box, is there anything recommend to change other than the oil? And what oil should I be using?

Quote:

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Originally Posted by Mieran

Instead of making lots of separate threads I thought it would be better to keep all questions in one place.

I will update as I progress.

1- What fuel pump? My car had a XE and an external GM pump, no idea what its capable of.

I was thinking Walbro 255?

2- The engine is running 291 BHP (apparently), is this intercooler good enough? LINK

3- I'm using F28 with flat type flywheel, I done some research and people are saying I need F28 clutch plate and F20 pressure plate. So I'm going to to buy a new F28 clutch kit and a second hand pressure plate, is this a good idea?

One more thing, what clutch do you recommend?

4- I might get a LSD for the box, is there anything recommend to change other than the oil? And what oil should I be using?

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1. good pump its what i run and im around the same figures
2. yup that will be biggenough as long as your not upping the power much more
3. cant use the flat fly with f28, f20 plate will not fit f28 box you need a pot fly wheel and full turbo clutch or an aftermerket lightened version of the pot fly wheel
4. sprip the box fully when fitting to check the syncros there still available and you will be peedoff if you get it all in and it crunches so you have to remove it again, and obviously you will need new diff bearings and id fit new drive shaft seals too

hope that helps

Thanks for the answers.

But I'm sure people have fitted a flat fly to a F28 before

the flat fly is when fitting an let with f20 if the engine is standard you can just get away with an uprated clutch, the imput shaft on a 28 is bigger than a 20 so the f20 plate wont fit,

the odball combo of f28 clutch plate and f20 preasure plate is used with a pot fly when you fit an f20, the f28 clutch plate will not fit a flat fly wheel either, just like late and early xes are not interchangable all lets had a pot fly wheel so the combo you listed will not work trust me

i have the same combo on mine potfly 28 clutch plate and f20 preasure plate with f20 box, got the full 28 clutch with the engine and its way to big for the 20 input so the 28 input is to big for a 20 clutch

the only way you can run a flat is with a silly speck paddle clutch so benefits are out weighed by cost imo

Hows using a f28 clutch plate on a f20 box possible? Aren't the splines different? :confused:

You might have a clutch kit made for a pot fly to suit a f20, all late coilpack XEs came with pot fly.

iv got it the wrong way then i have f28 bit that bolts to fly and f20 clut that goes on the splines

but as i said all lets had pots so the outer f28 bit wont fit a flat like with an xe you cant interchange early and late

i also tryed the flat fly with f20 full clutch and it was useless with phase 3 was fine on standard boost but on full boost car was slower than standard boost due to the amount of slip lol

i sould of gone with my words f20 friction plate f28 cover lol

and an xe cover wont give enough clamping on a flat as i am still using the same f20 bit just now have the 28 cover and pot fly

i realy shouldnt drink then try to articulate lol

Quick question.

What bolts can I use on the crank pulley?

I will be using a single pulley.

M8x25 cap head x 6 bzp not stainless

I can supply them. In allen key head.