Tb42 Conrods into Tb45

[Pottypirate]

Hi guys,
Just purchased a 98 Gu Ti which unfortunately will need a new bottom end.
As down the track I'd like to turbo it my engine builder has sourced some tb42 rods.
He was asking does this throw engine balance out at all?
I told him it seems a common swap and most turbos are running them.
Apart from the rods I'm just getting a stage 2 cam put in.
Are stock pistons okay?

First 4x4 after owning xr6 turbos. Wow their slow but I bought it as a tow vehicle not a race vehicle so all good.

Cheers Shaune

[Pottypirate]

Hi,
Can anyone help me here?
I need to know about engine balance with the tb42 rods and secondly will the stock pistons be okay with a low boost setup down the track?
If not do I need to go to forged( expensive) or will some other type suffice?
Also am I wasting money on the stage 2 cam that should be elsewhere, im just trying to build a reliable engine that will tow 2 t worth of horse float with ease.
Thanks Shaune

[Ben-e-boy]

If your worried about the balance source the crank from the motor the rods came from and install as matched set. No need to worry about throwing the balance out

[Pottypirate]

If your worried about the balance source the crank from the motor the rods came from and install as matched set. No need to worry about throwing the balance out

Okay good advice I'll see whether the engine builder can get his hands on the crank.
Any advice on pistons? Do I have to go forged or is there a cheaper option that will do the job.
Just building a reliable tow vehicle with the option of a turbo down the track to help pull the horse float easier, nothing stupid just make it a little more drivable.

[the evil twin]

Uummm... wouldn't the reciprocating mass (rods pistons etc) have bugger all to do with the rotating mass (crank, flywheel etc) balance?

Given the 42 and 45 have the same stroke (the 42 is a square engine and the 45 slightly over) I don't quite get the difference it makes.

Heavier piston/lighter piston, heavier rods/lighter rods wouldn't matter as long as they were blue printed or at least matched

[Pottypirate]

Uummm... wouldn't the reciprocating mass (rods pistons etc) have bugger all to do with the rotating mass (crank, flywheel etc) balance?

Given the 42 and 45 have the same stroke (the 42 is a square engine and teh 45 slightly over) I don't quite get the difference

I didnt really understand it either when the builder asked. I just schrugged my shoulders and said I dont know, seems to be the done thing, your the engine builder. He said to ask on this forum if there was any balancing needed. I figured as they are the same engine it would be a straight swap. Mind you, my mechanical knowledge is okay at best and my engine building knowledge is average. Seeing as though I was forced into a rebuild I want to do it right. Dont have any plans on stripping the engine again soon hopefully

[the evil twin]

Fair 'nuf...