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With different piston and rod sizes...

http://babelfish.altavista.com/babelfish/t...dett27rkit.html

Its good to find a use for all the years in school.

How exactly do you increase stroke by 2mm with a piston upgrade on standard crank? :confused:

And I don't need a web calculator, I remember my Year 7 volumetric formulas :Oops: Probably the first time I've used them since high school :)

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And the rings were properly seated and in full seal?

Adrian is right.

Synthetic is not a recommended run in oil.

These 2.7 and HKS 2.8 kits are ok for drag purposes and perhaps if they kit if cheap, go for it instead of your plain forged but until it gets to the OS Giken 3.0 litre set, I doubt that there's that much difference.

Maybe a bit more meaty torque in the middle?

T.

Yep, you read right. 5000km.

I can't imagine running 1.9 bar of boost on a new engine that has only done 1,500km.

Even if the engine was standard, I still wouldn't tune it to full power till at least 5,000km.

After spending over $10,000 on the engine, 5,000km is nothing mate.

5000km run-in??? That would take most people 6 months to complete. You really think that's a feasible run-in time?

What engine parts could POSSIBLY need 5000kms bedding in time??? :uhh:

No comment on the full-synthetic running in oil use... People have different ideas on that one, but the vast majority believe that mineral oil for the first 1000kms or so is still the best way to go.

You'll have to tell tuning shops like Top Secret, Still Way, Veilside etc. that it doesn't make much difference. Most of those tuners build track and high speed cars.

Regarding oils,

The less friction on an engine the better.

Adrian is right.

Synthetic is not a recommended run in oil.

These 2.7 and HKS 2.8 kits are ok for drag purposes and perhaps if they kit if cheap, go for it instead of your plain forged but until it gets to the OS Giken 3.0 litre set, I doubt that there's that much difference.

Maybe a bit more meaty torque in the middle?

T.

With different piston and rod sizes...

http://babelfish.altavista.com/babelfish/t...dett27rkit.html

 

Its good to find a use for all the years in school.

But you just linked me to the GREX stroker kit, and that's not what you have...

It's the crank in the GREX stroker kit that gives it the extra 2mm stroke, not the pistons or rods :P

And yes, I was pretty proud of myself that I remembered how to calculate volume of a cylinder without looking it up :) :Oops:

My kit isn't the stroker kit, it's the 2.7 ltr kit.

The stoker kit comes with the crank which I didn't get.

But you just linked me to the GREX stroker kit, and that's not what you have...

It's the crank in the GREX stroker kit that gives it the extra 2mm stroke, not the pistons or rods :D

And yes, I was pretty proud of myself that I remembered how to calculate volume of a cylinder without looking it up :D :Oops:

I cracked my old block in 4 places.

Id prefer to leave the extra 1mm bore thickness in the block and get a realible 7-800hp than boring it to 1mm of its life and drastically reducing the blocks rigidity . Have seen a block split at high horsepower with 88mm bore.

I don't think a thicker block gives you realibility.

If the block is going to crack, I honestly don't think 1mm is going to save you.

I've seen pistons and rods go through the side of a block with a standard sized bore due to spinning bearings.

As you may know, RB26 engines are renowed for spinning bearings which in turn will damage all kinds of things in the engine including the engine block.

I think it's the package that will give you realiablity.

Id prefer to leave the extra 1mm bore thickness in the block and get a realible 7-800hp than boring it to 1mm of its life and drastically reducing the blocks rigidity . Have seen a block split at high horsepower with 88mm bore.

1) It's the crank which determines the stroke of the engine.

2) The piston determines the bore size

3) A standard crank has 73.77mm of stroke

4) Running a piston designed for a stroker crank will leave you with a very very low compression ratio as the stroker pistons have a short pin to crown height to accomodate the additional stroke on the crank.

1) It's the crank which determines the stroke of the engine.

2) The piston determines the bore size

3) A standard crank has 73.77mm of stroke

4) Running a piston designed for a stroker crank will leave you with a very very low compression ratio as the stroker pistons have a short pin to crown height to accomodate the additional stroke on the crank.

I've already tried telling him that, but it doesn't seem to be getting through hsugh.gif

My kit isn't the stroker kit, it's the 2.7 ltr kit.  

The stoker kit comes with the crank which I didn't get.

Correct.

It's the crankshaft in the stroker kit that = 75.7mm stroke

You're running standard crank, so you've got a 73.7mm stroke (standard)

I think you might find that it's not just the crank that gives the extra stoke but also the combination of the piston height and conrod length.

The displacement was messured and was found to be just over 2.7ltr.

I'll have to check whether my rods a standard length or not.

Regarding compression, both my head and deck where milled to accomodate the setup the mechanic is seeking.

Correct.

It's the crankshaft in the stroker kit that = 75.7mm stroke

You're running standard crank, so you've got a 73.7mm stroke (standard)

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