New Big Block Gran Turismo Kit 200-245cc

[Yanker]

If I were going to put dead inertial mass anywhere in a bottom end it would be in the crank webs where the extra width could be used more positively to retain the crank pin and counter balance the moving parts without a huge torque load going through the mag side taper.

Keeping the revolving 'mass' and inertia the same then

(Sorry this post is for the hard of understanding defence league)

So variators a) weigh less, b) have a cush in terms of the pulley/belt etc. c) have an rpm progressive clutch: therefore do not suffer these probs?

The crank/flywheel taper is to ensure alignment at the same time as adhesion.

So the solution is a splined flywheel fitment that ensures ignition system alignment? Or an ignition system that is not so sensitive to alignment...eg external?

Sorry for this 'Blurt', curious tho....

[Mr G in NYC]

Any up dates ..progress.....news on the prototype/testing ?

Cheers G.

[Rich_T]

So variators a) weigh less, b) have a cush in terms of the pulley/belt etc. c) have an rpm progressive clutch: therefore do not suffer these probs?

The crank/flywheel taper is to ensure alignment at the same time as adhesion.

So the solution is a splined flywheel fitment that ensures ignition system alignment? Or an ignition system that is not so sensitive to alignment...eg external?

Sorry for this 'Blurt', curious tho....

Not sure what this is about?

Any up dates ..progress.....news on the prototype/testing ?

There are two prototype, the 200cc cylinder is running for the last 2-3 weeks and is doing very well. It is currently running in stock configuration PHBH30 and 42mm clubman. The second is a bit of a hotted up version 70mm bore and 62 stoke (235cc) with DT250 piston. The crank has to be fixed for this for run, it uses a 6H4 rod which comes back from surface grinding on Monday. Fingers crossed this cylinder will be running next weekend-ish. I have a meeting to finalise pattern tools on Wednesday. The plan is an intensive Dyno session for four engines later this month, the 2 big block GT kits, a small block GT development and the new LC barrel.

[RICSPEED]

new LC barrel.

intrested in this

[Muppet]

6H4 rod has 18mm wide big end eye; wots width after surface grinding and fitted t lambretta crank? DT 250 piston what year?

[Rich_T]

intrested in this

new LC barrel.

intrested in this

There are pictures earlier in this post on the LC. Prototype should be running in a couple of weeks. it is 76 bore on 60 stroke.

6H4 rod has 18mm wide big end eye; wots width after surface grinding and fitted t lambretta crank? DT 250 piston what year?

Wasn't aware they differed DT250's but it is the one with 25mm comp height. The 6H4 rod is being modified to fit in a wrecked Tino crank. This means surface grinding the bottom end to 16mm, using an RD BE bearing and shims.

The Big Block GT's start at 66mm bore with the 350LC piston, from there they use a combination of pistons up to 71mm bore (basically, 350LC, DT175, YZ250 88-98 and DT250).

[Mr G in NYC]

Thanks for the update ,

Best of luck with it.

cheers G.

[TED CRUD]

Its been a couple of weeks

[Rich_T]

It has been a couple of weeks, and the first 66 x 58 kit has been running extemely well.

It 's a bit of a head stractcher where all the power came from as there are a lot of small changes in this barrel over the small block and the difference between a small block bored to 66 and the big block at 66 is massive.

It hasn't been on the dyno yet, I'm waiting for two more engines to be finished before we spend a day up there. It cetainly does feel like 25bhp and it pulls from nothing and stays on the power really well.

The test engine is running with a Porcupine head and a huge squish (it is pretty low on the compression stakes) but is starts extremely well. Years ago, at Gran Sport, we used to get the GT206 demonstrator warm then play the game of trying to push the kick start to the floor as slowly as possible with out starting the engine. This new engine has the same properties, it is exceptionally easy to kick over.

I have some pictures which I'll post up in a bit.

[TED CRUD]

Sorry Rich-T not trying to rush you ,Just really eager to see the LC motor