Supercharger Discussion For all you misguided souls.
Sponsored by:
Sponsored by:

rotrex 1.6 vs 1.8

 
Old 07-10-2016, 08:23 PM
  #1  
Elite Member
Thread Starter
iTrader: (15)
 
Join Date: Sep 2010
Posts: 2,030
Total Cats: -111
Default rotrex 1.6 vs 1.8

I got really scared, and disheartened. THEN I saw that this was probably on a 1.6L and then I felt MUCH better!

I'm shooting for 260whp on a c30-94 and stock exhaust, but I have a 1.8L VVT witha flattop.

Good luck with sale!

thumpetto007 is offline  
Old 07-11-2016, 02:04 AM
  #2  
Junior Member
iTrader: (2)
 
Join Date: Nov 2013
Posts: 90
Total Cats: 5
Default

Originally Posted by thumpetto007 View Post
I got really scared, and disheartened. THEN I saw that this was probably on a 1.6L and then I felt MUCH better!

I'm shooting for 260whp on a c30-94 and stock exhaust, but I have a 1.8L VVT witha flattop.

Good luck with sale!
To be honest, even with larger motor and a 1.8VVT it will not feel as torquey as this setup. Back to back comparisons with a local 1.8VVT says that you may hit similar peak HP numbers, but the feeling is not the same. You really need a good set of cams to wake up the Rotrex's midrange power, none of which any current vendors offer as an out-of-the-box solution
Raisin is offline  
Old 07-11-2016, 02:17 AM
  #3  
VladiTuned
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 35,186
Total Cats: 3,166
Default

I beg to disagree



*edit: just realized this is a FS thread and not a discussion thread. My bad. Moving these 3 posts
18psi is offline  
Old 07-11-2016, 02:24 AM
  #4  
VladiTuned
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 35,186
Total Cats: 3,166
Default rotrex 1.6 vs 1.8

originally from this thread:

https://www.miataturbo.net/miata-par...0/#post1345306

Originally Posted by Raisin View Post
I'd call it a Kraftwerks "Race" Kit, but its really not anymore. Fits 90-93. Made 291WHP on E85, 246whp on pump on Dyno Dynamics.

Re-designed T6061 bracket for handling higher stress and better belt tension. Included are:

- Brackets
- Rotrex C30-94 blower
- Large intercooler and pipes
- Tial 50mm BOV
- Custom spec Kelford camshafts
- Custom Maxim Works Header with 3" outlet and anti-reversion
- Upsized Setrab Rotrex oil cooler

Price: $4000

Well sorted setup that provided years of enjoyment, only selling because my motor ingested a throttle body screw. Can split the package but the main bits need to go first.

Attachment 176354

Attachment 176355

Attachment 176356

Attachment 176357

Attachment 176358

Video of the car in action chasing a 600hp 996 Turbo:
UBCSCC - Mission Raceway - Chasing the Turdle - YouTube
18psi is offline  
Old 07-11-2016, 12:05 PM
  #5  
Elite Member
Thread Starter
iTrader: (15)
 
Join Date: Sep 2010
Posts: 2,030
Total Cats: -111
Default

Wait, did I start a new thread? I'm so dumb. Sorry lol.
thumpetto007 is offline  
Old 07-11-2016, 12:10 PM
  #6  
Elite Member
Thread Starter
iTrader: (15)
 
Join Date: Sep 2010
Posts: 2,030
Total Cats: -111
Default

Originally Posted by Raisin View Post
To be honest, even with larger motor and a 1.8VVT it will not feel as torquey as this setup. Back to back comparisons with a local 1.8VVT says that you may hit similar peak HP numbers, but the feeling is not the same. You really need a good set of cams to wake up the Rotrex's midrange power, none of which any current vendors offer as an out-of-the-box solution
Huh, good to know.

DO you have any dyno plots before and after the custom cams? Did you just replace the cams, no valvetrain mods? Care to PM the specs of the cams you got made? (long shot, but no shame)

Wait, don't I have different camshafts than you did before your customs? Did your local 1.8vvt have a flat top?
thumpetto007 is offline  
Old 07-11-2016, 12:21 PM
  #7  
VladiTuned
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 35,186
Total Cats: 3,166
Default

Originally Posted by thumpetto007 View Post
Wait, did I start a new thread? I'm so dumb. Sorry lol.
You didn't. I split these posts away from his FS ad that you posted in so it's not cluttered up.

I disagree with his statement though. 1.8 vvt will still make more torque and power than a 1.6, and over a broader range, even with a rotrex, and custom cams are not needed.
18psi is offline  
Old 07-11-2016, 12:37 PM
  #8  
Elite Member
Thread Starter
iTrader: (15)
 
Join Date: Sep 2010
Posts: 2,030
Total Cats: -111
Default

That is usually the case, but I'm curious to see what difference just the cams made for him.

I don't think I'll be lacking in torque (totally will compared to a turbo setup) but if I only make 200whp or like under 200wtq, through the stock exhaust, I'll get cams for sure.
thumpetto007 is offline  
Old 07-11-2016, 01:32 PM
  #9  
Newb
 
Join Date: Aug 2012
Location: Rowland Heights, CA
Posts: 38
Total Cats: -4
Default

As a point of reference, my car made 196whp with a c30-74 with a 75mm pulley. This is on a stock VVT motor with the stock exhaust system on 91 pump gas. During that tuning session the car was seeing knock. I now have a racing beat header and a 2.5" exhaust that's ready to go on and going to a retune soon. My torque curve looks similar in shape to the 949racing dyno plot above but with my peak torque at about 5.5k and much lower numbers (160wtq).
fredricktsang is offline  
Old 07-11-2016, 01:57 PM
  #10  
Elite Member
Thread Starter
iTrader: (15)
 
Join Date: Sep 2010
Posts: 2,030
Total Cats: -111
Default

What engine management were you on? What injectors? Do you think you were seeing knock because of the stock exhaust system?

I was reading that the backpressure on the stock exhaust is not a big of an issue with superchargers, while a turbocharger system would really not like it.
thumpetto007 is offline  
Old 07-11-2016, 01:59 PM
  #11  
VladiTuned
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 35,186
Total Cats: 3,166
Default

He was seeing knock because of 91. It is the worst. It will knock before mbt no matter what.
18psi is offline  
Old 07-11-2016, 02:16 PM
  #12  
Elite Member
Thread Starter
iTrader: (15)
 
Join Date: Sep 2010
Posts: 2,030
Total Cats: -111
Default

Oh ok. I'll just have to fill up on E85 when I'm in cali, and be careful filling up on my way over.
thumpetto007 is offline  
Old 07-11-2016, 03:59 PM
  #13  
Junior Member
iTrader: (2)
 
Join Date: Nov 2013
Posts: 90
Total Cats: 5
Default

Originally Posted by thumpetto007 View Post
DO you have any dyno plots before and after the custom cams? Did you just replace the cams, no valvetrain mods? Care to PM the specs of the cams you got made? (long shot, but no shame)

Wait, don't I have different camshafts than you did before your customs? Did your local 1.8vvt have a flat top?
I will have to dig up the old plots, there was about a year of gap in between having stock cams and receiving my Kelfords. Prior to that I also had a set of Chikara Stage II cams. Hopefully the screengrab is somewhere on my hard drive. The local VVT does have a flattop manifold, if it matters - I'm on a stock 1.6 IM.

Originally Posted by 18psi View Post
I disagree with his statement though. 1.8 vvt will still make more torque and power than a 1.6, and over a broader range, even with a rotrex, and custom cams are not needed.
Feel free to disagree but I would like to see some data: numbers, empirical, etc. to support your statement. While your statement may hold true for two equivalent stock 1.8v1.6 setups, I feel that once you crack open the block or head these statements are no longer valid. Custom camshafts are indeed needed and you will know what I mean once you go to a larger exhaust camshaft, as opposed to the traditional larger intake/smaller exhaust options that everyone currently offers. This is because blown motors behave differently than N/A or Turbo setups, in order to take advantage of the mass of air coming from the blower, the exhaust needs to vent as much as possible.

Originally Posted by fredricktsang View Post
As a point of reference, my car made 196whp with a c30-74 with a 75mm pulley. This is on a stock VVT motor with the stock exhaust system on 91 pump gas. During that tuning session the car was seeing knock. I now have a racing beat header and a 2.5" exhaust that's ready to go on and going to a retune soon. My torque curve looks similar in shape to the 949racing dyno plot above but with my peak torque at about 5.5k and much lower numbers (160wtq).
Like everyone said, if you want to run aggressive timing - Go E85.

Originally Posted by thumpetto007 View Post
What engine management were you on? What injectors? Do you think you were seeing knock because of the stock exhaust system?

I was reading that the backpressure on the stock exhaust is not a big of an issue with superchargers, while a turbocharger system would really not like it.
Read reply to 18psi, I feel that my perspective on the rest of the exhaust system is to have it as unrestricted as possible. Though this would not affect his knock threshold as much as the octane he is choosing to run.
Raisin is offline  
Old 07-11-2016, 04:50 PM
  #14  
SADFab Destructive Testing Engineer
iTrader: (5)
 
aidandj's Avatar
 
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 18,492
Total Cats: 1,635
Default

No e85 around MRLS. You will need to run 100 octane or something.
aidandj is offline  
Old 07-11-2016, 05:07 PM
  #15  
Newb
 
Join Date: Aug 2012
Location: Rowland Heights, CA
Posts: 38
Total Cats: -4
Default

Originally Posted by thumpetto007 View Post
What engine management were you on? What injectors? Do you think you were seeing knock because of the stock exhaust system?

I was reading that the backpressure on the stock exhaust is not a big of an issue with superchargers, while a turbocharger system would really not like it.
I'm running a MS3Pro with 610cc Flow Force Injectors. As others have said, I think the biggest contributing factor for the knock is the 91 gas, I'm not willing to go through the trouble of having to hunt down an E85 station all the time, I could do a flexfuel sensor but that might be a future project. The exhaust system may raise the knock threshold a little, but I shouldn't be able to hit MBT. I'm curious to see what difference it'll make, I guess I'll find out soon.
fredricktsang is offline  
Old 07-11-2016, 06:36 PM
  #16  
Elite Member
Thread Starter
iTrader: (15)
 
Join Date: Sep 2010
Posts: 2,030
Total Cats: -111
Default

Originally Posted by aidandj View Post
No e85 around MRLS. You will need to run 100 octane or something.
Ok, that's good to know. I'll have realtime flex fuel by the time I'm on my way to MRLS. Maybe I'll tune a bit with 18psi on the 100 octane before hand.

Best I can get in utah is 92 octane. There are like three E85 stations in the state, all of which are in salt lake city. Nevada 91 is much better than cali 91 (IIRC), so I should be ok filling up through nevada.
thumpetto007 is offline  
Old 07-11-2016, 07:04 PM
  #17  
Elite Member
iTrader: (8)
 
bahurd's Avatar
 
Join Date: Apr 2013
Posts: 2,605
Total Cats: 259
Default

Originally Posted by thumpetto007 View Post
Ok, that's good to know. I'll have realtime flex fuel by the time I'm on my way to MRLS. Maybe I'll tune a bit with 18psi on the 100 octane before hand.

Best I can get in utah is 92 octane. There are like three E85 stations in the state, all of which are in salt lake city. Nevada 91 is much better than cali 91 (IIRC), so I should be ok filling up through nevada.
You can always throw a bottle or 2 of octane booster in the trunk in case you run into problems finding the right fuel on the way.

5 Best Octane Boosters and Additives 2016 - MyCarNeedsThis
bahurd is online now  
Old 07-11-2016, 07:31 PM
  #18  
SADFab Destructive Testing Engineer
iTrader: (5)
 
aidandj's Avatar
 
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 18,492
Total Cats: 1,635
Default

Nevada has the same **** gas that CA does. So does Arizona.
aidandj is offline  
Old 07-11-2016, 07:36 PM
  #19  
Elite Member
Thread Starter
iTrader: (15)
 
Join Date: Sep 2010
Posts: 2,030
Total Cats: -111
Default

Originally Posted by bahurd View Post
You can always throw a bottle or 2 of octane booster in the trunk in case you run into problems finding the right fuel on the way.

5 Best Octane Boosters and Additives 2016 - MyCarNeedsThis
Thanks for the suggestion, but I haven't had good luck with octane boosters. They don't mix properly in the gas tank, and always cause bucking for me.

Oh well, I'll just have to not floor it the whole way. I'll be able to keep 120km/h the whole way no problem at half throttle.

Last edited by thumpetto007; 07-11-2016 at 07:44 PM. Reason: added correct unit of velocity
thumpetto007 is offline  
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
afm
Miata parts for sale/trade
13
11-16-2016 02:34 PM
Swanpuppy
Race Prep
12
06-06-2016 07:57 PM
nitrodann
Race Prep
17
05-27-2016 10:14 PM
thumpetto007
Media
16
05-20-2016 01:39 PM
Cxracer
Miata parts for sale/trade
6
05-10-2016 07:11 PM


Thread Tools
Search this Thread
Quick Reply: rotrex 1.6 vs 1.8


Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.