TR6 TR6 Motor rebuild Latest

[hondo402000]

TR6 Motor rebuild up-date

My engine is at the shop, the head has been cleaned magnetic particle tested, pressure tested and the porting has begun. the block had been cleaned and all plugs removed, they are ultrasonic testing the wall thickness of each cylinder to make sure we are good to bore out to 78mm, all indications so far is its good, I got a call from my engine guy and he informed me that he had a shop that made crank shafts and reworked cranks for racing and that they can and have removed 10 pound of weight from a TR6 crank last year for a race application, and has no effect on strength and then after its nitrided its actually stronger than the original, and since I probably will not hit 6000 RPM So I said go for it.

Hondo

 

[Hap Waldrop]

Re: TR6 Motor rebuild up-date

Removing weight from a crank increases acceleration rate, for sure the TR6 engine could benefit from this, but you'll find a aluminum flywheel can do the same thing for less money. I lighten alot of MG cranks for racing, this require alot more balance work than a unligtened crank. At the end of the day you will probably not notice much from the seat of your pants with the crank ligtened, most race drivers do not, not nearly as much as a lighter flywheel will. It's one of those things we do to a race engine when I'm doing the 10/10th approach. Also where you remove the weight from a crank is big time important where you remove the weight, you don't want to remove any weight from the counterthrows bottom, just concentrate on removing weight around the journal, in short you are trying to remove weight from the center of the mass.

 

[trrdster2000]

Re: TR6 Motor rebuild up-date

Hi Hondo, Good to see things moving along.

I agree with Hap, you will get much more out of a lightened fly wheel. You can either machine it off the original or get the aluminum replacement, both help. I would think 5 pounds off the original is easy.

Wayne

 

[hondo402000]

Re: TR6 Motor rebuild up-date

I also have the AL flywheel too. I have had much discussions with my rebuilder and I trust his judgement so with the Al flwheel and lightened crank, JE forged pistons and carillo rods he says its ALL goood. He says most of the weight is removed from the forging flashing thats left on during the manufacturing process and also since my crank it the earlier style its more robust( from what I understand)

Hondo

 

[Monkeywrench]

Re: TR6 Motor rebuild up-date

I also have the AL flywheel too. I have had much discussions with my rebuilder and I trust his judgement so with the Al flwheel and lightened crank, JE forged pistons and carillo rods he says its ALL goood. He says most of the weight is removed from the forging flashing thats left on during the manufacturing process and also since my crank it the earlier style its more robust( from what I understand)

Hondo

Sounds good to me. A very light rotating assembly will spin up very fast . As long as nothing is flexing, the lighter, the better, even if you keep your redline lower. Talk to your engine builder and make sure your valvetrain can keep up with the increase rate of acceleration (added pressure from a big cam is one thing, increase rate of spinning is another), though since it's not a 10/10 race motor, and it looks like you're using quality parts, whatever you have should work with no problem. Keep in mind, the motor's revs will drop much faster when you let off, but I'm sure you already know this.

Make sure you use a good damper like an ATI unit.

The secret to a great race motor (except for land speed and tractor pulling) is a super lightweight rotating assembly and a great flowing head. Everything else falls into place after.

 

[Brosky]

Re: TR6 Motor rebuild up-date

That thing should rev like a small block Chevy. It all sounds like a great plan. Keep us posted on the progress and make sure they are taking LOTS of pictures for you.

 

[hondo402000]

Re: TR6 Motor rebuild up-date

I have a set of roller rockers going on, CRMO pushrods and my builder is picking a cam he feels suitable for the engine and how I plan to drive it.

I do think he is documenting most of the rebuild for my benifit and his too

Hondo

 

[poolboy]

Re: TR6 Motor rebuild up-date

What ratio are the RR's ?

 

[Brosky]

Re: TR6 Motor rebuild up-date

Don't go too crazy with the roller rocker ratio Hondo.....that cam has plenty of lift and duration.

 

[hondo402000]

Re: TR6 Motor rebuild up-date

I got the 1,55 rockers and just because they have bearing, and my motor guy knows the ratio and is selection a cam based on the rocker ratio. so it good

Hondo