TVR RV8 pistons

[domV8]

What exactly are the pistons that came with a TVR RV8, as compared to standard RV8 pistons..?

Feel I should know this, but it rarely seems to come up - did TVR just take standard items and do the relevant machining, or did they commission bespoke items..?

I have a 1998 Chimaera 450 with a 4.6 engine that originally came with pocketed pistons - are they different from standard RV8 pistons with identical machining, or not at all..? Thinking in terms of manufacturer, cast/forged, etc. If so, what are the benefits..?

Thanks,

Dom

[Pupp]

Depends on the model/engine etc... range from forged Cosworth jobs on some exotic wedges to cast oem Rover. The later 4.6 pistons are apparently cast hypereutectics that are much improved over the traditional casts but not all 4.6s will have them as 4.0 pistons will give a higher static CR so are often fitted. I've never learned whether later 4.0 had better castings than the earlier ones. Dare say the info is out there.

The whole debate of forged v cast is a real can of worms

[domV8]

What, dare I ask, are the arguments given in the cast/forged debate..?!

I haven't heard of this, but it sounds very interesting...

Dom

[Simon says]

To my knowledge the serp 4.6 just as notched/cut outs stock 4.6 RR pistons, unless anyone knows otherwise.

[haircutmike]

4.0 ones are higher comp as stated, have no cut outs and are much stronger then for example the 5.0 ones which are made of Gouda.

4.6 ones are standard compression with cut outs and still stronger then the 5.0 ones.

[Pupp]

domV8 said:

What, dare I ask, are the arguments given in the cast/forged debate..?!

I haven't heard of this, but it sounds very interesting...

Dom

'ereyago

[TVR Thunder]

My Chim 500 was speced with 'pocketed pistons' BV heads and 11.2CR. Which makes it a 5.2L. So my engine builder informs me.

[domV8]

Hmm interesting - presumably the high CR is a result of the pistons, rather than the heads..?

Can anyone tell me what the max CR I could run safely on cheap supermarket 95RON would be..?

Thanks,

Dom

[TVR Thunder]

I'm pretty sure he said that the increased CR is due to my having a longer stroke and hence needing the pockets etc. He also advised that at this high CR to use a 97/99 RON & and Octane Booster!

I have put nearly 1000 miles (running in ) on the engine and I'm having a RR session next Friday to have it checked out before I give it any real Beans!