2.1 turbo? - SaabCentral Forums
*
Home Saab Pictures Saab Classifieds Saab Dealer Listings Saab Forum Saab Forum


Go Back   SaabCentral Forums > Saab C900, 1979-1993 & '94 Convertible (C=classic) > C900 Performance, Mods & Tuning

C900 Performance, Mods & Tuning Covers Tuning & Performance modifications for the Classic 900 (C900)

SaabCentral.com is the premier Saab Forum on the internet. Registered Users do not see the above ads.
Reply
 
Thread Tools Display Modes
  #1  
Old 20th October 2007
grif900's Avatar
grif900 grif900 is offline
Saab Lunatic
 
Join Date: May 2006                                                
Location: W. Yarmouth,MA. U.S.A.
My Saabs: 1988 900 SPG
Posts: 4,358
Question 2.1 turbo?

I am going through the prossess of thinning the heard again, but couldnt pass up a free 92 parts car. Its a n/a with an ill 5 speed, I think the box is a good candidate for a rebuild so I'm going to pull the thing out. I am also considering building up a fresh motor for my 88 spg. I've read here about using a 2.1 head to reduce compression and allow for more boost and using a 2.1 inlet manifold to help the engine breathe better (I think) but, what if I were to build the 2.1 for the spg? how can I lower the compression ratio from 10.1:1 to 9:1 ? It seems to me that shorter con-rods would do it but, are they out there to be had? Are the "dished" pistons for a turb eng. all it takes? Am I wasting my time thinking about this? Or is there more power to be had with an engine that will otherwise leave with the next load of scrap? Any thoughts , opinions or comments would be apreciated.

Last edited by grif900; 20th October 2007 at 06:24 PM.
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2  
Old 20th October 2007
TheRedBaron's Avatar
TheRedBaron TheRedBaron is offline
Saab on the Brain!
 
Join Date: Aug 2006                                                
Location: Washington, DC
My Saabs: 1990 900 turbo
Posts: 5,779
Default

Just pop the head on the turbo block - compression ratio will be maintained (unless you just want to replace the block). The difference in compression lies only in the stroke.
__________________
The faster you go, the more you see.
Reply With Quote Quick reply to this message
  #3  
Old 20th October 2007
grif900's Avatar
grif900 grif900 is offline
Saab Lunatic
 
Join Date: May 2006                                                
Location: W. Yarmouth,MA. U.S.A.
My Saabs: 1988 900 SPG
Posts: 4,358
Default

Quote:
Originally Posted by TheRedBaron
The difference in compression lies only in the stroke.
Not the pistons? My tiny little brain thinks the 2.1 would go. Say the 2 liter (1985 cc.) goes up to ten, then the 2.1 liter should go up to eleven right?
Reply With Quote Quick reply to this message
  #4  
Old 20th October 2007
TheRedBaron's Avatar
TheRedBaron TheRedBaron is offline
Saab on the Brain!
 
Join Date: Aug 2006                                                
Location: Washington, DC
My Saabs: 1990 900 turbo
Posts: 5,779
Default

Oh yeah, that may be part of it - the turbo pistons have that little dip which adds volume to the chamber.

Why not just do the 2.1 whole engine and do a water injection setup!
__________________
The faster you go, the more you see.
Reply With Quote Quick reply to this message
  #5  
Old 20th October 2007
grif900's Avatar
grif900 grif900 is offline
Saab Lunatic
 
Join Date: May 2006                                                
Location: W. Yarmouth,MA. U.S.A.
My Saabs: 1988 900 SPG
Posts: 4,358
Default

I am steering away from H2o and am leaning towards a c02 chilled homespun twintercooler.
Reply With Quote Quick reply to this message
  #6  
Old 21st October 2007
nnamssorxela nnamssorxela is offline
SaabNut!
 
Join Date: Jul 2007                                                
Location: Charleston, SC
My Saabs: RIP 1991 Saab 900s hatch :(
Posts: 491
Default

I've been told so many things i dont know what is right. I hear pistons are different sizes so just switching them wont work, but that the 2.1 has a better head and is better at the low end torque and accel? Also that the 2.1 has a better intake cam (or was it exhaust?) and that the other one is the same. Also I cant remember exactly, but the blocks might be made of different material and that the 2.1 will wear down faster. If you find something out, let me know! also, what exactly goes into a tranny rebuild? I was thinking of saving mine before it goes, but don't know what to do. Is checking for massive amounts of metal shavings a first step?

Thanks,
-Alex
Reply With Quote Quick reply to this message
  #7  
Old 21st October 2007
TheRedBaron's Avatar
TheRedBaron TheRedBaron is offline
Saab on the Brain!
 
Join Date: Aug 2006                                                
Location: Washington, DC
My Saabs: 1990 900 turbo
Posts: 5,779
Default

Quote:
Originally Posted by nnamssorxela
I've been told so many things i dont know what is right. I hear pistons are different sizes so just switching them wont work, but that the 2.1 has a better head and is better at the low end torque and accel? Also that the 2.1 has a better intake cam (or was it exhaust?) and that the other one is the same. Also I cant remember exactly, but the blocks might be made of different material and that the 2.1 will wear down faster. If you find something out, let me know! also, what exactly goes into a tranny rebuild? I was thinking of saving mine before it goes, but don't know what to do. Is checking for massive amounts of metal shavings a first step?

Thanks,
-Alex
Drain and refil the tranny fluid and see what comes out - if there was a lot of metal in there it could make the trans last longer to have fresh fluid, or it could just be changing rooms on the titanic. Supposedly the 2.1 head does flow better (probably more noticable at high rpm) than the 2.0. Matthew has said this gain is only really going to make a difference in high hp applications, but I'm not sure if he's done this himself. Personally, I'd say porting the 2.0 head would probably be just as good, as IIRC the valves are the same size. The intake cam for the 2.1 (same as the 2.0 n/a intake cam i believe) does net a slight tq/hp gain, saab themselves show this in some graph IronJoe posted. They actually started putting the n/a cams in the turbo engines in 9000s. The 2.1 block is regarded as a less robust casting than the 2.0.

And of course there will be conflicting info out there, this is the internet, after all!
__________________
The faster you go, the more you see.
Reply With Quote Quick reply to this message
  #8  
Old 21st October 2007
gorper gorper is offline
Saab Lunatic
 
Join Date: Aug 2002                                                
Location: US PNW
My Saabs: 86 turbo'd notch & 89T
Posts: 1,101
Default

Quote:
Originally Posted by TheRedBaron
The intake cam for the 2.1 (same as the 2.0 n/a intake cam i believe) does net a slight tq/hp gain, saab themselves show this in some graph IronJoe posted. They actually started putting the n/a cams in the turbo engines in 9000s. The 2.1 block is regarded as a less robust casting than the 2.0.

And of course there will be conflicting info out there, this is the internet, after all!
Yep, the 'net... :-)

If it's the same graph I'm thinking of, it comes from a Saab tech manual showing the power/torque of the first year of DI-APC (when they were in separate boxes, not together as DI/APC, in a single box). While that year the (Euro-only, one-year-only -- 89??) 9000T did use the same non-turbo cam fitted to all 16V B2x2 engines, it's not really possible to attribute the power gains to the cam itself.

These DI-APC-equipped engines had a much more complex timing system that could not only advance to the ragged edge of spark knock--like EZK had done for years--but now also run to the ragged edge of detonation under boost but nearly instantly retard timing upon knock vs. bleeding boost like a plain-jane APC. (DI-APC, like EZK, could also retard just the cylinder in which knock was occurring.)

Presumably, the DI-APC's better control and timing curve allowed Saab to bump the trapped compression a little by using the non-turbo cam, thereby increasing off-boost responsiveness. The added power probably came from being able to run less retard and closer to detonation under boost.

The c900/early 9000 vacuum/boost capsule timing control system was comparatively crude and I'd guess Saab was psyched to dump it from their turbo'd engines. Too bad it never made it to c900s, but the model was on the wane by then, and Saab was making <0$...

0.02
__________________
TeamD Alcan 5000 Feb 16-26
Reply With Quote Quick reply to this message
  #9  
Old 21st October 2007
TheRedBaron's Avatar
TheRedBaron TheRedBaron is offline
Saab on the Brain!
 
Join Date: Aug 2006                                                
Location: Washington, DC
My Saabs: 1990 900 turbo
Posts: 5,779
Default

Yep this is the one:



I guess Europe got the DI earlier than the US? I thought it came out in '91 for some reason.
__________________
The faster you go, the more you see.
Reply With Quote Quick reply to this message
  #10  
Old 21st October 2007
grif900's Avatar
grif900 grif900 is offline
Saab Lunatic
 
Join Date: May 2006                                                
Location: W. Yarmouth,MA. U.S.A.
My Saabs: 1988 900 SPG
Posts: 4,358
Default

Anyone have any more input on the quality of the 2.1 block? I will probably go to extremes with this project, d.i. is planned and m.s. on the horizon. For now, time is on my side.
Reply With Quote Quick reply to this message
  #11  
Old 22nd October 2007
Orca Orca is offline
Saab Lunatic
 
Join Date: Mar 2003                                                
Location: ܁
My Saabs: ܁
Posts: 4,222
Default

We have the 2.3 head from a 1993 9000 on our 1992 900 LPT. From what I understand, the 2.1 900s and 2.3 9000s use the same head. We fitted because of a head gasket failure and ... well ... why not?

Here's some data I grabbed from somewhere ... sorry the tabs are messed up:

Code:
16V Cams	 Inlet Lift	 opens	 closes	 dur	 SAAB	 Ex lift	 open	 close	 dur	 LSA	 Overlap	 SAAB
 	 (mm)	 (BTDC)	 (ABDC)	 (deg)	 Part #	 (mm)	 (BBDC)	 (ATDC)	 (deg)	 (deg)	 (deg)	 Part #
B202t  -1985	 8.65/6.65	 10	 56	 246	 7509201	 8.65	 56	 16	 252	 112	 26	 7509219
B202t cat -86	 8.65/6.65	 10	 56	 246	 7509201	 8.65	 56	 16	 252	 112	 26	 7509219
 	 	 	 	 	 	 	 	 	 	 	 	  
B202t  1986-	 8.65	 16	 56	 252	 7560808	 8.65	 61	 13	 254	 112	 29	 7560964
B202t cat 87-	 8.65	 16	 56	 252	 7560808	 8.65	 61	 13	 254	 112	 29	 7560964
 	 	 	 	 	 	 	 	 	 	 	 	  
B202i  1986-	 8.65	 16	 44	 240	 7561467	 8.65	 61	 13	 254	 109	 29	 7560964
B212i  1991-	 8.65	 16	 44	 240	 756095?	 8.65	 61	 13	 254	 109	 29	 7560964
 	 	 	 	 	 	 	 	 	 	 	 	  
B234i  90-93	 8.65	 13	 53	 246	 9116690	 8.65	 50	 16	 246	 109	 29	 9116708
B234t  91-93	 8.65	 13	 53	 246	 9116690	 8.65	 50	 16	 246	 109	 29	 9116708
You guys over that side of the pond didn't get LPT (or Lucas injection?), so think of it as a Bosch 16V without APC. The difference is quite noticeable, when in boost - even light boost. We used the cams out of the original 2.0 900 head, but I am led to believe that the normally aspirated cam from the 9000i on the intake side can be used for producing a more lower down power that is lost through the slightly lower compression of the head, which produces an advantage at high boost through better breathing and less propensity to knock.

The core difference is the ports as far as I can see:

Code:
B202 Intake - 28x38 (153 cfm) Exhaust - 31x43 (160 cfm) 
B234 Intake - 27x42 (192 cfm) Exhaust - 27x42 (170 cfm)
Later on, we're going DI. The Lucas systems fuel really well and most Lucas cars have a 3.3 bar FPR anyway. In fact, Shan has a thread about moving from Bosch LH to Lucas CU:
http://www.saabcentral.com/forums/sh...ad.php?t=92538

There's a really good DI installation walkthrough here:
http://www.uksaabs.co.uk/viewtopic.php?t=1529

... this way a DI/APC installation on an LPT car. DI+APC is different. AFAIK, DI was fitted as a piggy-back system to the 1988 9000 CD model only. That is a snap to fit to APC equipped 900s, apparently and detailed on http://www.900aero.com - DI/APC is a little more involved and perhaps removing APC to start with would be a good move? Much easier on an LPT, since there is no APC to start with, so the whole system is just dropped in place.

I think I got all that right, but if I dropped a clanger somewhere, please correct me.

Last edited by Orca; 22nd October 2007 at 05:03 PM.
Reply With Quote Quick reply to this message
  #12  
Old 22nd October 2007
xassh's Avatar
xassh xassh is offline
SaabNut!
 
Join Date: Oct 2004                                                
Location: Southern California, USA
My Saabs: 1992 900 turbo 5 sp.
Posts: 310
Default

i too have plans for building a motor and am very interested in any info i can pick up. i have been told that the 'best' combo would be using the 2.0 block (i had always presumed it was because the oil line fittings for the turbo are cast in, rather than having to drill them in) with a 2.3 head (which requires some modifications at the timing chain/chain cover area to get it to seal properly, with a 2.1 intake manifold (only 1990-93 c900's had the larger intake, '89 down N/A engines use the same intake as all the 16v turbo cars).

too bad i had never heard anything concerning the 2.1 intake manifold until well after i had all ready gasket match ported and polished my intake manifold to the head, which was also ported/polished. i got bored and decided to smooth the outside of my 2.0 intake manifold as well, there are no sand casting marks and i am sure i gained an extra 5hp by polishing the outside *nod*.

i wonder what the drawbacks are to turbo'ing a N/A engine. are there any beyond the fact that the bottom end torque will help your transmission find its way to an early grave? are there any sacrifices at the top end of the rpm range?
Reply With Quote Quick reply to this message
  #13  
Old 22nd October 2007
Orca Orca is offline
Saab Lunatic
 
Join Date: Mar 2003                                                
Location: ܁
My Saabs: ܁
Posts: 4,222
Default

I've heard about the problems at the timing chain end - our head went on as a direct swap. I wonder if it's a pre/post 1993 thing ... short block/long block? Does someone know for certain?
Reply With Quote Quick reply to this message
  #14  
Old 22nd October 2007
Saab-Daniel's Avatar
Saab-Daniel Saab-Daniel is offline
Saab Lunatic
 
Join Date: Jul 2003                                                
Location: Orlando, Florida
My Saabs: '91 Monte Carlo 'vert
Posts: 2,876
Default

I know with 100% certainty, that the difference lies between short/long engine-block switch over, moving to short-block in MY94. My brother did a head-swap on his 1993 9k aero, used a 1994-on head. It had to be modified around the timing-chain. A bit had to be machined out, and some welding had to be done to make it fit.
Daniel.
__________________
Still preaching MS...!
They call him... "The Reverend"....

Now with C900 Monte Carlo Convertible, weekend-cruiser :-)
Reply With Quote Quick reply to this message
  #15  
Old 22nd October 2007
Orca Orca is offline
Saab Lunatic
 
Join Date: Mar 2003                                                
Location: ܁
My Saabs: ܁
Posts: 4,222
Default

Awesome ... nice one, Daniel
Reply With Quote Quick reply to this message
  #16  
Old 22nd October 2007
dlb dlb is offline
Senior Member
 
Join Date: Apr 2005                                                
Location: U.S.A.
Posts: 186
Default

Hey guys, take a look at this http://www.geocities.com/schaafer84/

This is Jared's 2.1 liter turbo. If you search some old posts you can find more info on his setup.

I hope he dosen't mind me posting this.
Reply With Quote Quick reply to this message
  #17  
Old 22nd October 2007
Orca Orca is offline
Saab Lunatic
 
Join Date: Mar 2003                                                
Location: ܁
My Saabs: ܁
Posts: 4,222
Default

Quote:
Originally Posted by TheRedBaron
I guess Europe got the DI earlier than the US? I thought it came out in '91 for some reason.
The CD model had a kind of piggy-back DI system on top of APC for model year 1988. That model is useful to pull the DI system and place on top of an existing APC system in a 900. From there, so yes, 1989 (perhaps some 1988), DI/APC was installed as a single system into the 9000. So, was it 1991 in the US? Does anyone definitively know?
Reply With Quote Quick reply to this message
  #18  
Old 24th October 2007
grif900's Avatar
grif900 grif900 is offline
Saab Lunatic
 
Join Date: May 2006                                                
Location: W. Yarmouth,MA. U.S.A.
My Saabs: 1988 900 SPG
Posts: 4,358
Default

Quote:
Originally Posted by dlb
Hey guys, take a look at this http://www.geocities.com/schaafer84/

This is Jared's 2.1 liter turbo. If you search some old posts you can find more info on his setup.

I hope he dosen't mind me posting this.
Thanks for the link. Some good info there, I saw a lot of things I wont do. Jared turbed his 2.1, thats not quite what I am planning.I want to build a long-haul reliable Saab motor. I Have been doing a little homework, and belive I found turbo pistons that will work in the 2.1 block. I still need to explore the cam issues. I suppose its easy enough to keep the cams and lifters to together as sets, so I can use whatever will work best with whatever ign/fuel set-up I use.
Thanks to all for the input,keep those cards and letters rolling in.
Reply With Quote Quick reply to this message
  #19  
Old 24th October 2007
nnamssorxela nnamssorxela is offline
SaabNut!
 
Join Date: Jul 2007                                                
Location: Charleston, SC
My Saabs: RIP 1991 Saab 900s hatch :(
Posts: 491
Default

what pistons are you going to use? I was on a similar quest, but my emails never got answered
I might opt to fullfil my turbo blues else where and keep my saab running....slow. I think a turbo motorcycle would be cool...
Reply With Quote Quick reply to this message
  #20  
Old 24th October 2007
nuclear_jimbo's Avatar
nuclear_jimbo nuclear_jimbo is offline
Senior Member
 
Join Date: Dec 2004                                                
Location: Cleethorpes
My Saabs: 1992 Abbott T16S
Posts: 181
Default

Quote:
Originally Posted by grif900
Say the 2 liter (1985 cc.) goes up to ten, then the 2.1 liter should go up to eleven right?
Actually, I think it would go up to 10.5...

Sorry, I'll get my coat
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Bookmarks

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the SaabCentral Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 09:31 PM.



Powered by vBulletin® Copyright ©2000 - 2014, vBulletin Solutions, Inc.

top of page | sitemap | email us



copyright © 2003 - 2011 saabcentral.com, All rights reserved http://www.whiter.co.uk - valid xhtml - valid css
SaabCentral is an independently run website and is not affiliated in any way to Saab Automobile AB.


Garage Plus vBulletin Plugins by Drive Thru Online, Inc.