944T Engine Rebuild
- Thread starter barks944
- Start date
944 turbo cabrio
New member
I have also looked at Lindsey for at set of pistons. They can be delivered coated if you want..... 
So far they have been cheapest of what I have found.
I know a company called Wahl in Germany have modified standard pistons for other 2,8 builds in Germany but personally I prefer to be 105% safe and buy new pistons wit a CR of 8,5:1. I'm primarily in it for the better boost and torque build up
Cheers
Niels
So far they have been cheapest of what I have found.
I know a company called Wahl in Germany have modified standard pistons for other 2,8 builds in Germany but personally I prefer to be 105% safe and buy new pistons wit a CR of 8,5:1. I'm primarily in it for the better boost and torque build up
Cheers
Niels
I see that if you use stock pistons, S2 crank and short rods you get 9:1Cr which is prob a bit too high like you say! My current favourite idea is to stick with the 2.5 block and use a rotrex supercharger. This is about £1500 but its very efficient compared to old designs. Much less friction in the gearing, only about 2% of total kinetic energy used to drive the supercharger. 2 of these are used on the Konigsegg CCX(R). Theres no need for the stroker with this as you have boost across the rev range and you get 0 lag.
DivineE
New member
Sorry just got back to this. S2 crank and Carrillo rods (standard dimensions). The engine ran over 400hp in a 968 race car that was reversed into a wall at 120mph. As far as I know the engine survived and went on in another car.
The kit was bought from Promax before it became Promax motorsport and I think was the Andial kit from the states. The original white 2.8 Promax car still lives too so the 2.8 kit has proved to be quite a reliable way to go.
If I remember correctly, my engine is supposed to have 8.5:1 CR. Piston bowls have been enlargened somewhat but the tops are not any thinner than stock. I think the strenght hasn't been compromised much. The obvious benefit of course is that if you have cylinder bores and pistons in good shape, you don't have to get the block machined. (which seems to be hit and miss with the tolerances and all that) It'll save some money and work too.
If I was to do this now I'd probably go for 3 liter or bigger though. If you are buying pistons and rods and having the block machined anyway the difference in total cost isn't that much.
I have dynoed the car once when I bought it four? years ago. It made 320 bhp at 1 bar. Torque was 450 Nm or so. It had a Lindsey sport turbo -what ever that is and a Vitesse MAF. I have been having persistent hesitation problems ever since and the tune is not optimal. I am now changing the turbo and exhaust and possibly engine management as well. I am hoping to get some more power with same boost.
But anyway I think the extra displacement itself doesn't give you much power over the stock. It does have an effect on driveability though. Bigger engine definately feels stronger off boost.
If I was to do this now I'd probably go for 3 liter or bigger though. If you are buying pistons and rods and having the block machined anyway the difference in total cost isn't that much.
I have dynoed the car once when I bought it four? years ago. It made 320 bhp at 1 bar. Torque was 450 Nm or so. It had a Lindsey sport turbo -what ever that is and a Vitesse MAF. I have been having persistent hesitation problems ever since and the tune is not optimal. I am now changing the turbo and exhaust and possibly engine management as well. I am hoping to get some more power with same boost.
But anyway I think the extra displacement itself doesn't give you much power over the stock. It does have an effect on driveability though. Bigger engine definately feels stronger off boost.
Olli
Mine were bought about 5 years ago now, but they came in the exact same Mahle box with the same markings on the piston, a friend in the US sourced them for me. At the time they were one of the last sets left in 104mm. These low compression pistons were never available as a standard piston from Porsche in this bore size and were a special commision. Andial had sets made in 104mm and in 104.5mm, they all sold out as far as I am aware although there have been limited batches of the 104.5 that have come out since. I think I have a pic somewhere that I could dig out if you need photographic evidence I can email it to you, the number on the side is 103.98.
Mine were bought about 5 years ago now, but they came in the exact same Mahle box with the same markings on the piston, a friend in the US sourced them for me. At the time they were one of the last sets left in 104mm. These low compression pistons were never available as a standard piston from Porsche in this bore size and were a special commision. Andial had sets made in 104mm and in 104.5mm, they all sold out as far as I am aware although there have been limited batches of the 104.5 that have come out since. I think I have a pic somewhere that I could dig out if you need photographic evidence I can email it to you, the number on the side is 103.98.
Just checked through an old post I made on rennlist about the clearances of my bore and pistons and Scott Gomes from Under Pressure performance posted that he had the last set of 104mm i.e. standard size pistons, for sale and that was back in 2004, which was also when I bought mine so in fact 7 years ago not 5! Time flies when your modding cars
Thom
The point is that if you are turbo charging your own S2 or 968 engine, you do not have to do anything to the bores, if they are within tolerance and not scored you can just fit these pistons, some carillo rods and a 2.7 head and you are good to go. No need to touch the bores.
The point is that if you are turbo charging your own S2 or 968 engine, you do not have to do anything to the bores, if they are within tolerance and not scored you can just fit these pistons, some carillo rods and a 2.7 head and you are good to go. No need to touch the bores.
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