2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.
Sponsored by:

S4 NA rotors into S4 TII engine q's (searched)

Thread Tools
 
Search this Thread
 
Old 05-13-05, 10:21 PM
  #1  
Senior Member

Thread Starter
 
MountainTurbo's Avatar
 
Join Date: Jan 2004
Location: Utah (land of mountains)
Posts: 515
Received 0 Likes on 0 Posts
S4 NA rotors into S4 TII engine q's (searched)

Going to be rebuilding my S4 TII engine here pretty quick, and I had a couple quick questions.

The engine will be streetported, fairly largely. For now, the turbo will stay stock, with close to stock boost levels. Eventually a small hybrid will be used, but I'm going to keep it small since this car is mostly a DD/autox car. Tuning will be done with an SAFC, and secondary injectors will probably be upgraded to 720cc.

I have a set of S4 NA rotors that I'm considering putting in. Reason being, since this car will be an autox car, I wonder if using the higher compression rotors will give a little more power down low, since the street port will probably take away some low-end grunt.

I realize tuning will be very important, but any other thoughts/issues you guys have?
Old 05-14-05, 01:04 AM
  #2  
Super Raterhater

iTrader: (6)
 
SonicRaT's Avatar
 
Join Date: Dec 2001
Location: NY, MA, MI, OR, TX, and now LA or AZ!
Posts: 10,624
Likes: 0
Received 2 Likes on 2 Posts
Yeah, you'll be OK, the difference isn't very large, so it's not all too bad, especially for the levels you plan to run. Just run it a little bit richer and you'll be ok, also you'll be able to make more power at lower boost levels, so keep that in mind when cranking it up.
Old 05-14-05, 10:14 AM
  #3  
Respecognize!

 
Whizbang's Avatar
 
Join Date: Sep 2004
Location: Anchor Bay, CA
Posts: 4,106
Received 71 Likes on 42 Posts
might want to balance the rotating assembly seeing you are using a different eccentric with different rotors...but not sure how bad it would really be...
Old 05-14-05, 10:35 AM
  #4  
Banned. I got OWNED!!!
 
gonzz's Avatar
 
Join Date: Mar 2002
Location: Las Vegas, NV
Posts: 4,236
Likes: 0
Received 0 Likes on 0 Posts
All e-shafts are the same.. just make sure you use a S4 front counterweight with a S4 TII flywheel. That will keep it balanced
Old 05-14-05, 12:52 PM
  #5  
Senior Member

Thread Starter
 
MountainTurbo's Avatar
 
Join Date: Jan 2004
Location: Utah (land of mountains)
Posts: 515
Received 0 Likes on 0 Posts
Originally Posted by gonzz
All e-shafts are the same.. just make sure you use a S4 front counterweight with a S4 TII flywheel. That will keep it balanced
So are you saying to use the counterweight off the NA, or the TII?
Old 05-14-05, 01:03 PM
  #6  
I wish I was driving!

 
Join Date: Dec 2001
Location: BC, Canada
Posts: 5,241
Received 84 Likes on 68 Posts
Originally Posted by MountainTurbo
So are you saying to use the counterweight off the NA, or the TII?
Front counterweights are identical between N/A and TII ofthe same series.
You would need to use a TII S4 flywheel.
Old 05-14-05, 02:10 PM
  #7  
Senior Member

Thread Starter
 
MountainTurbo's Avatar
 
Join Date: Jan 2004
Location: Utah (land of mountains)
Posts: 515
Received 0 Likes on 0 Posts
Originally Posted by scathcart
Front counterweights are identical between N/A and TII ofthe same series.
You would need to use a TII S4 flywheel.
Ah, gotcha. So basically, just use everything off my current TII motor, and swap rotors.
Old 05-14-05, 09:39 PM
  #8  
Make Money.
iTrader: (6)
 
eriksseven's Avatar
 
Join Date: Oct 2003
Location: Seattle
Posts: 4,137
Received 8 Likes on 2 Posts
I'm running s4 N/A rotors in my s4 TII with slightly extended RB street-ports (pretty big).

Since doing the rebuild nearly 4000k miles ago, I've had no problems whatsoever. I've set my MBC so that max boost is at 10psi on the stock turbo (ported WG), stock IC, and stock fuel (cleaned 550cc's) etc.

I don't notice a huge difference, but I'm sure it helps a little on the DL.
Old 05-14-05, 11:55 PM
  #9  
Lives on the Forum

 
RETed's Avatar
 
Join Date: Feb 2001
Location: n
Posts: 26,664
Likes: 0
Received 16 Likes on 15 Posts
Originally Posted by eriksseven
Since doing the rebuild nearly 4000k miles ago, I've had no problems whatsoever.
Wow, 4,000,000 miles since the last rebuild???
4 million miles???
Sorry, I couldn't resist.


-Ted
Old 05-15-05, 12:03 AM
  #10  
Rotary Enthusiast

iTrader: (1)
 
turbine's Avatar
 
Join Date: Sep 2004
Location: seattle wa
Posts: 906
Likes: 0
Received 0 Likes on 0 Posts
i plan to use a set of 85 gsl se rotors in an 88 t2 (stock 3 mm apex seals high compression) run water injection and 15 psi
shooting for 350 whp
Old 05-15-05, 02:16 AM
  #11  
Make Money.
iTrader: (6)
 
eriksseven's Avatar
 
Join Date: Oct 2003
Location: Seattle
Posts: 4,137
Received 8 Likes on 2 Posts
Originally Posted by RETed
Wow, 4,000,000 miles since the last rebuild???
4 million miles???
Sorry, I couldn't resist.


-Ted
haha... shaddup, lol.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
immanuel__7
Megasquirt Forum
3
08-22-15 09:34 PM



Quick Reply: S4 NA rotors into S4 TII engine q's (searched)



All times are GMT -5. The time now is 01:10 PM.