G+S 2.1 Pistons and Liners

Post by **Pickles** » 17 Mar 2006, 10:55

I have had a price of £175 for piston and liners from G+S seems a good
price. They are made by Cofap in Brazil according G+S.
Any one no if they are any good I assume they are cast, what compression ratio will they give me. There is a good article on Pistons on the Go Westy site but I am not sure which it is any help.

Post by **toomanytoys** » 17 Mar 2006, 11:21

Dunno...
but might be worth popping on a set of german rings..
what part number do they corespond too? what engine do G+S say they are for?
DJ, has thinner rings apparently....and all the combustion chamber is in the piston top, so you could work out what difference there is..

I sent you some mails.. but no replies.. did you get em?

Post by **Pickles** » 20 Mar 2006, 14:02

They are for 2.1 they also do 1.9 kits a bit cheaper.
I will try and get some more details.

I have not received any e-mails from you
I have sent you a few e-mails

Any luck on building a bigger motor
sourced any 97mm pistons that fit.
I am going down the turbo 2.1 megersquirt route. With dual maps one for
petrol and one for lpg. Different advance on both

PM me

Post by **Pickles** » 25 Mar 2006, 21:40

Come on somebody must have used the G&S 2.1 cofap piston and liners.
Don't you all rebuild engines on a weekend

Post by **HarryMann** » 25 Mar 2006, 22:21

Not dem fings, nope

Soundsa gooda price though !

About = one Sunbaru piston!

Post by **Pickles** » 31 Mar 2006, 14:42

Spoke to GSF a bloke called Keith at head office (very friendly)
but could not give me much detail. He said they were listed for the DJ engine. As I like to question things. I asked him if they did pistons for the MV, SS engines he said they werent listed. I know for a fact that they sell them in the states cofap. On the Go Westy site they say the Cofap piston
gives a compression ratio of 8.3:1 not very good

Brazilian-made 94mm piston-425 grams
76mm crankshaft stroke
2110cc actual displacement
137mm connecting rod
2mm piston/cylinder head clearance
8.3:1 compression ratio, too low
Piston Dish 43cc Standard MV 47cc

Part No of the US cofap pistons
Price: $404.34
Part Number: 025 198 075D
Cofap 94mm pistons and cylinders for Water Boxer Vanagon 2.1L engines. More Info

GSF part No Cofap 16509B PISTON+BARREL SET T25 2.1 Water Cooled > 11/90 165.00 + vat £194.00 incl vat

Just Kampers Cofap
T25 Piston & cylinder set (4) 2100cc watercooled DJ engines
J10356
Price: 249.00 inc vat
Cofap No 025 198 075Z

Different Suffix to US
Any one shed any light on all this or am I rambling on and nobody gives a
!!!!!!!!!!!!!

Post by **HarryMann** » 31 Mar 2006, 23:39

Something doesn't seem to add up there...

Theres not enough data really, but IF the head is flat (valves flush with head surface) and ignoring spark plug volume

Cyl Capacity = 527.5cc

2mm head gap x Bore area = 13.88 cc
Bowl volume 43 cc

C.R. = 527.5 + (43 + 13.88)/(43+13.8816)

C.R. = 10.277

Allowing 1cc for spark plug (say)

C.R = 10.11

So ther must be some volume in the head somewhree, but haven't a 2.1 head to hand to look...

But, here we have an increase in swept volume, and a significantlty reduced bowl volume compared to an MV. Unless that 2mm head clearance is significantly less on an MV, how do we get such a low ratio. Both the reduced bowl vol and increase in swept volume should raise it... ?
I've got a figure of 9.0 for an MV ?

But if thats what the mfrs say it is, then that should be right and that ratio fits for an engine running on low quality fuel, or dubious sources of fuel found all over the Americas. They're not promoting the pistons for high performance, are they...

So put a mild turbo on it

just a whiff should do it, that ratio is not far off what it should eb for a bit of boost

Post by **toomanytoys** » 03 Apr 2006, 15:50

IIRC heads are about 15cc...
So agree clive, something isnt quite right...