whats the difference

[ever88]

Can someone please inform what the difference is between the naturally aspirated and turbo 944 2500cc models are please.

generally, manufacturers build the turbo model with forged internals such as crank rod piston setup but there are a surprisingly amount of engines with virtually identical internals on the basis the boost levels are quite low.

I'm curious to know the difference as I begin looking at the possibility of fitting a blower to to a nat aspirated engine running 5lbs of boost. I still consider I would be safe but it doesn't hurt to ask the question about how porsche did build them. It's probably irrelevant as the turbo models will run a higher boost than I will anyway.

cheers
Paul

 

[Diver944]

The Turbo had stronger pistons (early ones were forged) and runs at 8:1 compression ratio with 12psi of boost

The N/A runs high compression at 10.9:1 but at only 5psi boost should be fine. There are supercharger kits on the market that run up to 7psi on standard N/A internals

 

[ever88]

I have not purchased a blower as yet and would like to view such kits if you could point in right direction.
cheers

 

[Diver944]

Try http://www.speedforceracing.com and http://www.ninemeister.com/

I'm not sure if Ninemeister have ever done one for a 2.5 but they have done several 3.0L's

 

[Guest]

If you look at this ad for the 944 turbo from 1986 it shows you what the differences are ...... []

http://www.flickr.com/photos/kenrosario/138505401/sizes/l/

 

[appletonn]

Great picture!

Don't forget the boost gauge.. ...oh and the special bracket to hold your wallet...[8|][][][]

 

[Peter Empson]

Simon at ESS has plans to SC his 'track slag' Lux, so at this rate there could be quite a few cars running around with them fitted [] His is going to be a diy conversion using an Eaton blower from a Merc.

 

[ever88]

this is my intention also.

I have ran through the calulations myself to see how fast I need to spin it and know there is plenty of room with the air box removed.

I'm just running through whats required really but need to sell my M Coupe to avoid arguments with the Mrs.

would be nice if he posted a thread on this to see how he is going about it.

my intentions are to spin the eaton M45 blower at 2 to one revolution of crank.
use the MAF sensor to detect flow on inlet of blower.

use a blow off recirc back to blower inlet and finally use an index linked fuel pressure regulator to richen up when needed. I'm informed to try this 1st without moving spark and see if there are detponation issues.

I'm curious to see if others do it differently.

 

[Peter Empson]

I dont recall many other details of what he's planning, but I'll ask him when I next see him. One thing you can be sure of though, lots of cable ties are bound to be involved []

 

[carreraboy]

I guess you are probably better to ask on the 944 Forum which is extremely active [s1]

 

[tscaptain]

Moved.......[]

 

[John Sims]

I don't know off hand but my guess is the later one includes level adjustment. Certainly the 944 takes two different headlamp units subject to year and origin (US headlamps don't fit UK Turbo/S2's as an example).

 

[GlennS]

I don't know off hand but my guess is the later one includes level adjustment.

Your guess may be correct, but I am not 100% convinced. Both part numbers are listed in the "up to MY91" PET catalogue. That covers the 944 2.7, the S2 and the later Turbos; so the "944" referenced is the 2.7. Both my 2.7 and my S2 have headlight level adjustment.

Of course, it is always possible that someone has retrofitted level adjustment to my 2.7 at some point in the last 20-odd years!