Was a Paxton supercharger conversion, now a Rotrex C38-91

Post by **Coops** » Thu Apr 15, 2010 3:31 pm

how much did that cost mate????

stevieturbo · Post by **stevieturbo** » Thu Apr 15, 2010 6:19 pm

I think the crank pulley was around £300 or so.

But obviously bare in mind thats a whopping chunk of aluminium its made from. I know the one I want will be circa 8.5" diameter. Terry's is slightly smaller.
so teh billet would be about 8.5" x 3" thick to start with.

The idlers etc and blower pulley are around £100, or a little more each.

The idlers and blower pulley

Post by **Coops** » Thu Apr 15, 2010 6:30 pm

well its looking more like im going to use the o/e crank pulley use a single belt and get the charger pulley made,
i think i need a 5" pulley on the charger as the bottom serp one is 6.75"

stevieturbo · Post by **stevieturbo** » Thu Apr 15, 2010 6:42 pm

That should be easy to achieve. He'll likely have a PAS pulley off the shelf of the same dimensions, and may just require work to the centrebore/keyway or something

I know most of the PAS stuff sells for mid £100's or less.
Or maybe a crank pulley off another vehicle might be suitable for the bower with a little work.

Post by **Coops** » Sun Dec 12, 2010 9:51 pm

just an update,
while sorting out the workshop at caprisport today,
i found a 3" 6 rib pulley, that with opening the hole out a fraction and cutting another keyway, (handy when capsport knows machine shop guys),
will fit the charger,
meaning i just need to draw up and get an adaptor 4" pulley made to bolt to the bottom pulley, to drive the seperate belt to the charger,
had to go this dual belt route as the charger fouls on lots of things when sat back inline with the O/E belt and pulleys,
so have a spare bottom serp pulley to play with to make something that locates in the lower pulley and drives the charger,
will report back once i have had a play,

i have had the bottom end balanced, with this affect it much?

Post by **Coops** » Sun Dec 12, 2010 9:54 pm

change that,
a 3" charger pulleys means i need a 3.75" bottom pulley to give 36075rpm @ 6500rpm

or have i got things a little mixed up

is the charger ratio 4.40 or 4.44 ??

using this: http://www.v8forum.co.uk/supercharger_speed.xls

kiwicar · Post by **kiwicar** » Mon Dec 13, 2010 10:17 am

Hi Tony
At 4" it will be 6.5% faster, that would about cover any belt slippage, I would go for the 4" bottom pully, should be fine.
(I probably have just contradicted somthing I have previously said but I don't think you will over rev it if you keep the engine revs below 7K)
Best regards
Mike

stevieturbo · Post by **stevieturbo** » Mon Dec 13, 2010 10:21 am

better fast than slow. And the larger diameter the less chance of slip.

Post by **Coops** » Mon Dec 13, 2010 7:14 pm

i'll only be reving her to about 6k with a possible accidental rev to 6.5k.

will get on drawing up the 4" bottom pulley, and get the 3" pulley opened out etc to fit the charger.

cheers

topcatcustom · Post by **topcatcustom** » Tue Dec 14, 2010 9:15 am

Come on Tony- how long is your 6k limit going to stick?! When you hear that thing whine and realise it will keep spinning the wheels right up to 7 grand you'll keep your foot planted! Especially seeings how well you built your bottom end and have those nice top hat liners in there

Post by **Coops** » Tue Dec 14, 2010 7:16 pm

nah 6k with odd burst to 6.5k mate,
even set the ecu up for that too,
i just want it up and running with the charger can then play a bit afterwards

kiwicar · Post by **kiwicar** » Tue Dec 14, 2010 7:43 pm

Hi Tony
I have a spare 3.3" six rib CV pully here if you are interested, 2 pin drive type with a 1" hole down the middle.
Best regards
Mike

Post by **Coops** » Tue Dec 14, 2010 7:46 pm

pm sent mate

Post by **Coops** » Sun Jan 30, 2011 11:38 pm

right,
as room is very limited in the front of the cappa,
will this intercooler be ok to use???
http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... K:MEWAX:IT

stevieturbo · Post by **stevieturbo** » Sun Jan 30, 2011 11:44 pm

Coops wrote:right,
as room is very limited in the front of the cappa,
will this intercooler be ok to use???
http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... K:MEWAX:IT

it's quite small.

I'd have thought a Capri would have plenty of room ?

What sort of layout do you use at the front with the rad ?

Where is there room for the pipes to enter/exit the IC ? sides, top, bottom etc ?

ie, would something like this fit ?

http://cgi.ebay.co.uk/FORD-SIERRA-ESCOR ... 1549wt_922

Not saying it is good or bad. But at least going down that route, if you did decide to upgrade later, parts are off the shelf and not custom.

or you could maybe look into buying say 2-3 Cossie 4x4 intercoolers and welding up new end tanks yourself ?
At last proper cores like that will be good quality. Welding OE cores is actually quite common too.