Show full size 924Board.org
Discussion Forum of 924.org
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 
 Technical FAQ924 FAQ (Technical)   Technical924 Technical Section   Jump to 924.org924.org   Jump to PCA 924 Registry924 Registry

My new project
Goto page Previous  1, 2, 3 ... 10, 11, 12
 
Post new topic   Reply to topic    924Board.org Forum Index -> General Discussions
View previous topic :: View next topic  
Author Message
Carrera RSR  



Joined: 08 Jan 2010
Posts: 1412
Location: Somerset, UK

PostPosted: Tue Jul 25, 2017 3:56 am    Post subject: Reply with quote

5th injector was first unplugged during initial start ups to avoid bore wash before and during running in. We found it was not needed and never plugged it back in.

No exhaust info. It was made by a UK stainless specialist. It expands to 3.5-4'' off the turbo then tapers back to 2.5'' at the union with the tail section. No middle box. The large exit off the turbo will give little to no back pressure on the turbine housing allowing faster spool up. Tapering ensures the hot gasses maintain velocity out the pipe as the gasses cool. Sounds good too!

Don't see why 1.0 bar isn't achievable. Forged pistons allow more scope for error when pushing the limits of the motor. Stock pistons haven't got that luxury.

Data is king to pushing the motor so gauges for AFR, boost and temps is a must. Also look at some kind of detonation monitoring too.

MLS and ARP head studs are also worth investing in
_________________
1980 931 - forged pistons, Piper cam, CGT turbo, 951 ducted FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife LSD
Now www.924board.org/viewtopic.php?t=34690
Then www.924board.org/viewtopic.php?t=31252
Back to top
View user's profile Send private message
924-76  



Joined: 05 Jun 2006
Posts: 1190
Location: Ontario, Canada

PostPosted: Sun Aug 13, 2017 6:02 am    Post subject: Reply with quote

Rainy day, note the FMIC






_________________
1976 924 N/A ROW SOLD
1980 931S
Back to top
View user's profile Send private message Send e-mail
Fasteddie313  



Joined: 29 Sep 2013
Posts: 1402
Location: Not Detriot - NMI

PostPosted: Sun Aug 13, 2017 10:29 am    Post subject: Reply with quote

Very nice looking build!!

The 951S turbo is a direct swap, it has the same bearing housing geometry and turbine wheel/shaft as the 931, but it is a bit expencive..

If you want a bigger compressor on the cheap you can take a compressor off of a 951 non-s and it will go right on.. You can get one of those turbos that need a rebuild for $100-$200, just make sure it didn't get so bad that the compressor wheel met the housing..

I think the 2664 turbo will get you to 1bar fine but not much more.. I did a lot of pulls with a 2664 and fmic @ 1bar and it seemed to be fine.. Then I did a lot of pulls with the early 951 compressor and it was a lot better feeling but I developed a small head gasket compression leak to my coolant system and that's the last it ran since I dove into my injection project..

How did you route your intake plumbing from the turbo to your IC?
_________________
1980 931S LSD FMIC
Back to top
View user's profile Send private message Yahoo Messenger
924-76  



Joined: 05 Jun 2006
Posts: 1190
Location: Ontario, Canada

PostPosted: Sun Aug 13, 2017 8:50 pm    Post subject: Reply with quote

Fasteddie313 wrote:
If you want a bigger compressor on the cheap you can take a compressor off of a 951 non-s and it will go right on.. You can get one of those turbos that need a rebuild for $100-$200, just make sure it didn't get so bad that the compressor wheel met the housing..

I think the 2664 turbo will get you to 1bar fine but not much more.. I did a lot of pulls with a 2664 and fmic @ 1bar and it seemed to be fine.. Then I did a lot of pulls with the early 951 compressor and it was a lot better feeling but I developed a small head gasket compression leak to my coolant system and that's the last it ran since I dove into my injection project..

Thanks for the info, so all you need is an non-s 951 compressor wheel with is compressor housing?


Fasteddie313 wrote:
How did you route your intake plumbing from the turbo to your IC?

From the turbo, I went up to cross over the frame rail and down behind the headlight, through the IC to the other side, up behind the other headlight and cross over the frame rail and into the GTS intake.
I use 2.25 inch diameter piping to keep it the same as the turbo outlet.
_________________
1976 924 N/A ROW SOLD
1980 931S
Back to top
View user's profile Send private message Send e-mail
924-76  



Joined: 05 Jun 2006
Posts: 1190
Location: Ontario, Canada

PostPosted: Sun Aug 13, 2017 9:13 pm    Post subject: Reply with quote

Fasteddie313 wrote:
Then I did a lot of pulls with the early 951 compressor and it was a lot better feeling...

Could you elaborate on this? How was it better? Less or more lag?
Thanks
_________________
1976 924 N/A ROW SOLD
1980 931S
Back to top
View user's profile Send private message Send e-mail
Fasteddie313  



Joined: 29 Sep 2013
Posts: 1402
Location: Not Detriot - NMI

PostPosted: Mon Aug 14, 2017 1:31 am    Post subject: Reply with quote

924-76 wrote:
so all you need is an non-s 951 compressor wheel with is compressor housing?



You need parts: A, B, C, and maybe 7 and 8..
I don't recall which compressor had the different sized compressor side piston and rings, "mating rings, compressor seal"..
A= "seal plate" / backing plate..
One of the backing plates used a smaller diameter piston..

BTW I could not get the k26/6 water cooled bearing housing to work, I think it may have been the thickness of the hot side heat shield but putting the 931 turbine housing on it with the 931 turbine the turbine wheel would hit the turbine housing because I think the heat shield plate spacing was wrong and the heat shields would not swap..

924-76 wrote:

Could you elaborate on this? How was it better? Less or more lag?
Thanks


Well the 2664 spooled faster but had to be really spooled up to make boost, the k26/6 compressor spolled a little slower but made boost with less spool..
The k26/8 compressor would make 1 bar of boost at around 2800-2900 RPMs if you were pulling against the breaks or 3000-3100 RPM WOT in 2nd..

Hmmm
Id say the bigger compressor makes better turbo noise and feels like a cleaner more solid power/torque on boost as compared to the 2664 that felt a little strained close to 1bar.. The bigger compressor turns a noticable amount less RPM to make the same boost and is a more efficient air pump at that level.. It had a less likely to explode feeling..

Same with adding the intercooler, I could immediately tell that the engine was much happier at WOT, even more powerful at the same boost.. The bigger compressor just stepped that feeling up another notch..

Hard to explain but scientifically the bigger compressor is more efficient at 1bar so the turbo is turning less RPMs to make that boost and will last longer because of this, should have lower post turbo pre IC IATs too..

The best way I've found to disassemble turbos..
Take the compressor housing and turbine housing off..
Loosen the nut off of the compressor wheel so the nut is a little past flush with the end of the shaft..
Use a small brass hammer to tappity tap tap the shaft out the back of the bearing housing, hitting it on the nut as to not damage the end of the shaft, catch the turbine wheel/shaft as it comes out the back and not let it fall all the way through so you can see the order of parts behind the backing plate still..

It's just that the shaft is a really tight fit on the compressor wheel and you need to tap it through the compressor wheel..
A lot of places say to heat the compressor wheel and pull on it and all sorts of stuff but it hasn't worked for me.. Just tap the shaft through it..


I suppose you should send it in to have it balanced as an assembly but the parts are already mostly balanced individually and weren't balanced in the 80's like they do today anyway..

Most definitely use loctite on that shaft nut and torque it down pretty good..
_________________
1980 931S LSD FMIC
Back to top
View user's profile Send private message Yahoo Messenger
924-76  



Joined: 05 Jun 2006
Posts: 1190
Location: Ontario, Canada

PostPosted: Sun Aug 20, 2017 5:51 am    Post subject: Reply with quote

I still need to clean up/tidy up things, but I though I'd share a picture of my engine with the GTS intake manifold fully installed and functional.

The installation included:
-GTS intake manifold
-Front Mounted Inter-Cooler
-Universal 2.25 inch inter-cooler piping with silicon coupling.
-Modified 931 S2 air charge tube.
-Dual air temperature gauge: 1 sensor half-way between the turbo and the inter-cooler and 1 few inch before the throttle body (post inter-cooler)
-Lindsey Racing silicon vacuum hose kit (5/32 inch)
-Custom build 5th injector bracket / intake port. (see picture above)
-Modified barb connector to fit under the intake (re-circulation valve).
-944 coolant tank
-Modified alternator bracket
-Modified catch can/oil separator bracket
-Home made (using few original parts) throttle body cable. The 931 throttle cable was too short.

Next on my list:
-Strut brace (sitting in my garage)
-Adjustable cam gear...maybe...
-Seats
-And I'm still thinking about the 951 turbo conversion


_________________
1976 924 N/A ROW SOLD
1980 931S
Back to top
View user's profile Send private message Send e-mail
Display posts from previous:   
Post new topic   Reply to topic    924Board.org Forum Index -> General Discussions All times are GMT + 10 Hours
Goto page Previous  1, 2, 3 ... 10, 11, 12
Page 12 of 12

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group