Stock, stroker or ghetto capacity increase? ( supra 7m gte pistons bmw rods )

[prj]

Sorry, i thought the price was for 1 piston not for 6!!!!! although that comment here is questionable: "High Quality piston set, same as what came in the 7M-GTE stock."

http://www.supramania.com/forums/sho...20-NPR-pistons
From what I understand they are the same as stock.
And the stock ones are fine to 600hp...

[Billman]

it gets cheaper

http://mizumoauto.com/product/view/id/230

[Rusty]

that is cheap... +0.5mm too, or is that getting a little silly...

[prj]

Out of stock tho.
Well, anyway, I guess we established that they are really cheap
But I guess if you find a 7M-GTE at the breakers, you can probably have them even cheaper. Though not sure if there is a point to getting them over the new ones.

I'd like to see more of these Frankenbuilds around. Props to the original creator who thought outside the box.
He has a mid-engined Ur-Quattro btw. Just to give you an idea

[A80Avant]

dont you have any valve pocket modifications to fit those?

only thing i dont like is the low compression, but for a track car, that is ideal.

[Rusty]

can always deck the block a tad, if you want a little more compression, but as you're skimming the pistons, you should be able to customise the comp. ratio easily enough.

[Billman]

the pin diameter must be 22mm on them.

[Rusty]

One thing I do remember from various over bored engine builds, is the headgasket was an issue. Has this been solved now, or is it still something that has to be custom made / machined?

[A80Avant]

i know 034 have a ready gasket for 83mm


and machining the deck is an option but how much can you go from 8.5 to? If you want close to 9:1 or more, its going to be quite i bit machining, isnt it?

[prj]

8.5:1 is very nice for 400+hp car. Can run cool EGT's, lots of timing, perfect for the track as well. Fuel economy does not suffer a lot.
And yes you can customize the CR easy enough.

Nothing needs to be done to the head for this to work.
The car I tuned is great off boost... well there is no "off boost" with this tiny turbo.
It has more power and torque in every place of the map than a stock car.

Just timing needs to be adjusted on the dyno. We are running upto 45 degrees in some spots.

[Error404]

Gasket is the problem on the 83mm bore, I brought that up recently re: using a 7A block and concensus was to use a 7A gasket and o-ring the block.

[G60Rallye]

If it was a road car I would go for a stroker without question. If you are going to use it for any sort of racing, circuit work or drag racing I would stick with the standard stroke. Your always going to be up in the higher revs so its should always be on boost. Therefore you would just be running higher piston speeds for no real gain as you would be out of its low down torque advantage.

[Rocco]

Gasket is the problem on the 83mm bore, I brought that up recently re: using a 7A block and concensus was to use a 7A gasket and o-ring the block.

Alex,do you know ehre you can buy O-rings for our cylinder blocks?

[Error404]

you make them out of copper

[Rocco]

you make them out of copper

and do you know how much it cost?

i have ready to machine my AAT stroker block,and a 034 Motorsport 82mm copper head gasket.... maybe it is a good chance