Scooterotica

The New Gran Turismo Big Block tooling is complete and the first castings done. The machining jigs are being made over the Christmas Break and production parts will be available mid-back end of January 2013. The kit is 100% cast and machined in the West Midlands and features all the proven technical features that are available in the current Small Block design but with the added bonus of 1. Improved Exhaust port profile 2. 66mm - 71mm bore capacity (potental of 20 oversizes) 3. Boysen ports 4. Larger transfers 5. Larger boost ports 6. Larger Exhaust 7. two new inlet manifold options 8. New balanced and flowed crank options. 9. Off the shelf packing plate options.

Target price is sub £400, specification dependant.

To register your interest contact me over Scooterotica or call Gran Sport.

sounds good, if as successfull as the small block kit, looking for a big block touring kit, rich what carb and exhaust do you think will be best for touring with this kit ?

still cat iron then, thats a shame

Looking good Rich. It'll be nice to see how these perform.

Adam

dave wheeler wrote:still cat iron then, thats a shame

You have to remember that the Small Block GT186 kit put a lot of TS1 225 kits to shame even though it was a full 40cc smaller. It managed to achieve this in cast iron too which kind of turned conventional wisdom of plated barrels on it's head. It is considerably harder to produce a barrel in iron than it is to produce it in aluminium (I've cast barrels in both) yet I still elected to go cast iron. This is not done out of shear belligerence, it is done for a series of very carefully considered reasons.

Now the GT kits have gone up to the 200 casing it will be interesting to see how a cast iron barrel compares in this arena; remember that Eden's barrel puts out 27 odd BHP without any ill effects. This cylinder has the capability to match it.

The new manifold options are 30mm on the L/H side for PHBH30 carbs and 34mm carbs on the R/H side for Mukuni or similar (not VHSB 34 as the bore is bigger than 34mm).

dave wheeler wrote:still cat iron then, thats a shame

Why?

I Must admit the Precision moulding and the casting quality looks fantastic, it will be a very interesting future topic no doubt :fb:

Good luck with this kit

Interesting indeed
Rich, will the new manifold fit the 186 cylinder, enabling a PHBH30 on he LHS?

soulsurfer wrote:Interesting indeed
Rich, will the new manifold fit the 186 cylinder, enabling a PHBH30 on he LHS?

Yes, the reed valve is common to both kits as is the big bore exhaust gasket face (although the gasket face is moved 4mm further outboard so the flange is a little thicker and the stand off from the bore face is longer). The Porcupine head will also be available for both and there are new GT balanced 58 and 60mm cranks arriving shortly.

Having enjoyed two small block kits i can't wait to see a big block one on the road.