14 replies to this topic

[PACINO]

Hi everyone and happy new year! First question: - Are these high compression pistons? Second: - Is there much difference between these Swiftune "Die cast" and the forged Omega (of course in their price) for daily use?

Thanks in advance!

[nicklouse]

As they have a 6.5 cc dish I would say they could allow I HC build without having to skim things too much.

 

but they could very easily give a too high CR with some race heads.

 

https://swiftune.com...-pistons-2.html

Edited by nicklouse, 01 January 2023 - 12:52 PM.

[Cooperman]

Those pistons are really for very high compression and high revving engines suitable for competition.
For normal road use the 21253 is ideal. It has an 8.4 cc dish volume and if fine for CR's of up to around 10.5:1.
The price is good as well.

[PACINO]

Thanks Nick and Cooperman. Yes, they are 6.5cc, but the question I have is whether to buy these pistons or the forged Omega ones. It is true that I am not going to compete on the circuit, but I will use it daily and I like to step on the accelerator.

Should I keep the "Die cast" or buy the forged ones? I ask about the level of guarantee, effectiveness, compression and durability of the rings.

Your opinions are appreciated.

[imack]

Never used the die cast Swiftune pistons but you'll have no problems with the die cast Omegas.
Most of the currently available forged Omegas use a smaller than standard gudgeon pin so you need to use appropriate aftermarket con rods or bush the small end of the factory rod.

[Spider]

Forged Pistons are generally more robust than Cast and also much more expensive. I'm not implying here that Cast pistons are weak or inferior, they are usually well up to the job for just about any street engine, even in light boosted applications.

[OzOAP]

I use cast Omegas or Swift pistons in most road applications. MED state cast Omegas good for up to 11:1cr
They all use the same piston rings.

[Steve220]

Thanks Nick and Cooperman. Yes, they are 6.5cc, but the question I have is whether to buy these pistons or the forged Omega ones. It is true that I am not going to compete on the circuit, but I will use it daily and I like to step on the accelerator.

Should I keep the "Die cast" or buy the forged ones? I ask about the level of guarantee, effectiveness, compression and durability of the rings.

Your opinions are appreciated.

Unless you're racing it, I wouldn't bother with forged. Modern aftermarket cast pistons are quite strong.

[Cooperman]

I have 21253 pistons in my 1990 Cooper 1330 and it has 10.4:1 CR.
It really does run well and the pistons are fine. I have just done an engine refresh with new rings and even after doing a lot of hard work pistons look great.

[PACINO]

I have 21253 pistons in my 1990 Cooper 1330 and it has 10.4:1 CR.
It really does run well and the pistons are fine. I have just done an engine refresh with new rings and even after doing a lot of hard work pistons look great.

That is precisely what I want. Avoid in the not too distant future having to open the engine to change the rings. Cooperman, I also have those pistons in the engine and they look great but ..., the rings have worn out very quickly. They have only lasted 30K kilometers.

3 years ago. When I lifted the cilynder head:

Edited by PACINO, 01 January 2023 - 07:32 PM.

[PACINO]

Thanks to Imack, Spider, ozOAP and Steve220 for your answers. I belive then that I have made a good purchase and I will forget to change them for forged pistons.







Regards

[nicklouse]

Have re read this thread I think there maybe a bit of language misunderstanding.

 

high compression pistons. This normally describes the geometry of the piston. Rather than the quality of the product.

[PACINO]

Cooperman said yesterday that these pistons are really for very high compression.

[sonscar]

Did you clean the pistons and bores with Scotchbrite pads?I was lead to believe they were impregnated with abrasive and should be used with caution.This may be complete codswallop of course.Steve..

[PACINO]

Hi Steve. Yes, I only cleaned the top of the pistons. And it was with a smooth Scotchbrite pad.

Regards!