11 replies to this topic

[bigrob]

Hi guys

So ive just got hold of a metro turbo engine, needing a rebuild.

Now im looking to rebore so im going to need bigger new pistons.

Are any of the new pistons available gonna be up to the task? Or are there specific ones needed?

Cheers guys
Rob

[jonny f]

http://www.med-engin...istons-die-cast

 

Or forged if you can afford it. Obviously you need to get the correct CR though depending on the boost you want to run.

[bigrob]

Brilliant cheers. Is there of a budget option? Im planning on running pretty much standard boost

[Ethel]

21253's should be ok. Minispares Mega are a bit cheaper than those KAD ones too

[Turbo Phil]

21253's are a good piston & can be dished out to about 11cc if required. The cast Omegas are also an excellent choice.

Phil.

[MIGLIACARS]

turbo phil

 

Can you explain to me the advantages of the forged pistons over the di cast pistons that med sell. apart from the weight!!!!!!!!!!

[mini13]

well the cas one is cast... so it will always be more brittle than a forged one.

[MIGLIACARS]

so there stronger then !

 

 

are the cast med ones prone to breaking!!!!

 

what will break them!!!!  

 

 high revs        !!!!!!!!!

 

 

to much boost!!!!!!!!!!!!

 

 

heat!!!!!!!!!!

 

 

 

were the metro turbo standard pistons forged or cast!!!

[Ethel]

Revs are the main issue, forging makes them stronger which means they can be made thinner & lighter which reduces the inertia that goes up with the revs. A cast piston can be just as strong, but if it is it'll also be heavier. As you can build a turbo engine that doesn't use any more revs than a normal road car you could argue lightweight internals aren't so critical. That's why the original Metty Turbo pistons are right bruisers.

[Turbo Phil]

The cast ones certainly aren't prone to breaking. I've run a minimum of 15psi on mine & over 20psi on occassions without issue, rev limiter set at 7,000.
Phil.

[MIGLIACARS]

Ok thanks.

 

With all the above said then, would med s forged pistons have any benefits over there di cast pistons on a forced induction set up.

14 psi

rpm red line 7700

[hankins]

Bump...

 

Also interested to know the answer :)