2.4T Piston options

impmad2000 · Post by **impmad2000** » Mon Jul 23, 2007 1:00 pm

OK, so I'm doing a rebuild on the engine, see other thread. I'm pretty sure tht I'll find some wear in the barrels. I have cast iron barrels (T motor)
What are my options ?
I can get the barrels re-bored, can I get oversized pistons to suit ?
Obviously there are better P and B sets available, but at a relatively high cost. What is a good (sensible priced, fair performance ) upgrade I should consider ?
I'm sure you've all got some crazy ideas. Want to pass some of them on ?
Cheers
Tim

johnM · Post by **johnM** » Mon Jul 23, 2007 1:40 pm

Hi Tim

I have just gone through the same process, you can overbore your barrels and buy custom made pistons from JE. pistons run at about £100 each but for every non standard machining alteration there is a charge of I think £20 ie 84mm piston is standard 84.5 is non standard so that would count as 1 alteration. If you decided to go with a non standard compression ratio that could also count as an alteration. So you would be looking at about £720 for pistons they come without rings so rings would be £100 to £120 (non standard) and then you have to find somebody to bore your barrels out. What you end up with is 6 barrels and pistons that are not matched and will not be as good as mahle pistons and barrels. I found some well priced new mahle pistons and barrels from www.ebsracing.com and they came in at around £1300. They arrive this week

Hope this helps, of course there is import duty to pay on all of these prices

Regards John

Gary71 · Post by **Gary71** » Mon Jul 23, 2007 1:54 pm

Hi Tim,

Check out this thread:

http://www.ddk-online.com/phpBB2/viewto ... ht=pistons

davidppp · Post by **davidppp** » Tue Jul 24, 2007 9:29 am

Hello, Tim.

depends on budget as usual!

I happen to have just taken apart a "just rebuilt" 2.4 MFI engine..the pistons and barrels look to be newly replaced: the story was the engine never ran right after the rebuild..

So Those are available at a budget price..

But I'd highly recommend the high-compression route with E or better cams..

Kind regards
David

Gary71 · Post by **Gary71** » Tue Jul 24, 2007 7:20 pm

How about these?

http://cgi.ebay.co.uk/PORSCHE-911-2-4E- ... dZViewItem

impmad2000 · Post by **impmad2000** » Tue Jul 24, 2007 8:08 pm

yeah ? Any thoughts anyone?? Not sure I'd trust them, am I being too picky.
I could go and see them perhaps ?
I'm torn 'cos I really don't want to cheapskate too much.
I may put the whole engine bit on hold till I've finished the rest of the car....
Cheers
Tim

Gary71 · Post by **Gary71** » Tue Jul 24, 2007 9:05 pm

I was tempted myself

Just to put to one side for when the time comes.

As you say who knows what you are actually buying, all you can go on is the feedback which is 100%. Not Porsche related feedback, but at least gives an indication to the honesty of the guy.

He has some cylinder heads for sale as well

davidppp · Post by **davidppp** » Tue Jul 24, 2007 10:17 pm

Hello all.

If those are really in spec, they might be worth buying'.

The 2.4 E is actually a forged piston unlike any other E..but like all forged 911 pistons suffers from top ring groove widening quite quickly, especially if revved...

Allow 100 quid for rings, and clips..

Honing is a whole 'nother thing..a really good quality honing is only possible on very lowmileage barrels..and is about 10-15 quid a pot...

A grape hone is much less of course..

Bottom line..secondhand pistons and barrels are not really worth using IMHO..the cost difference compared to new pistons and bored barrels is less than 10% of the rebuild cost..and you can choose your own CR etc...and use E or better cams!

Kind regards
David

impmad2000 · Post by **impmad2000** » Wed Jul 25, 2007 7:18 am

davidppp wrote: Bottom line..secondhand pistons and barrels are not really worth using IMHO..the cost difference compared to new pistons and bored barrels is less than 10% of the rebuild cost..and you can choose your own CR etc...and use E or better cams!

This is the way I'm starting to think. When the rest of the re-build is going to cost minimum of ~£1k any way !
Tim

johnM · Post by **johnM** » Wed Aug 01, 2007 10:17 am

Hi Tim

my piston and barrel option pitched up this week they look great, not the cheapest option but still they work out at £260 including import duty and VAT per barrel and piston which is not bad when you see how much work goes into them.

Now all I need is to glue it all back together

Regards

Gary71 · Post by **Gary71** » Wed Aug 01, 2007 10:47 am

Where did you source them? That's a great price for new barrels and pistons.

hot66 · Post by **hot66** » Wed Aug 01, 2007 10:49 am

if you read Johns post again Gary, it is per barrel & piston

johnM · Post by **johnM** » Wed Aug 01, 2007 11:05 am

My Mrs hasn’t worked out that its £260 per barrel/piston yet

well the kids could do with going on a diet, bread and water for the next 6 months I think.

impmad2000 · Post by **impmad2000** » Wed Aug 01, 2007 11:05 am

They look Good. Big cut outs for S cams then ?
My plan now is to get the bits measured, checked and held pending my go-ahead. Might buy bearing shells now is availability may mbe an issue . I will then continue on with the bodywork and save the engine til the end. At that point I'll be either A) fed up and want to do a cheap job
or B) be totally over the moon with the rest of the car and want a real screamer in the back !!
We'll see.
Ian, If you want your engine stand back , it is now stored with the motor on athe shelf.

Cheers
Tim

Gary71 · Post by **Gary71** » Wed Aug 01, 2007 12:56 pm

hot66 wrote:if you read Johns post again Gary, it is per barrel & piston

Doh

If it looks too good to be true it usually is!