Page 1 of 2 12 LastLast
Results 1 to 15 of 16

Thread: Anybody Running Gen4 ZX10R (2011-2015)

  1. #1

    Anybody Running Gen4 ZX10R (2011-2015)

    Just Curious if anybody is having good luck with this engine. We have been running it this year with minor success. While the top end power is great, it lacks seriously in bottom end. We have to gear it low and run the rev limiter hard. Mine is all stock down to the airbox. Any speed secrets? Aftermarket airbox/velocity stack combo is extremely expensive. I would buy one if I knew it would help alot. I have played with cam timing and gotten it better, but not perfect.

    Any help would be appreciated.


  2. #2

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    The Gen 4 is the HP King however their mid-range power as you are seeing is way down. Running it on the limiter is also not a good idea, they tend to spit rods doing that.
    I developed a one off setup for the Gen4 that helps the mid-range a ton. How Much??? After the first couple races last season Bobby Michnowicz having the same issue your having switched his Gen4 powerded Minisprint to my setup and not only won the California Lightning Sprint Championship, he finished first in every race he ran the car in, running both So Cal and No Cal races.
    As I said the stacks are one off, designed and developed just for this motor. They will fix your problem.

    Give me a call, Monte Crawford

    Performance Fabrication

    High Velocity Intakes

    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	P1010104.jpg 
Views:	61 
Size:	96.4 KB 
ID:	15725   Click image for larger version. 

Name:	P1010234.jpg 
Views:	62 
Size:	94.6 KB 
ID:	15724  

  3. #3

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    Here's a bit of video, box stock Gen4, watch him come thru traffic on the outside, after he clears traffic watch the car accelerate, nothing has been able to run with this car.

  4. #4

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    A couple questions. What is the weight of a Mini Sprint vs Dwarf Car (my car 1100 lbs no driver)? If they are chain drive, he probably can get the gear ratio closer than us using toyota gear ratios. We run 1/4 mile tracks, usually hooked up. Final drive choices 11:38, 11:76, 11:97.

  5. #5

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    Not really sure what your asking, you say your already on the limiter, doesn't really make sense.
    The video is of a 1/4 mile track, on a 1/4 mile track making mid-range power is going to be even more critical.

  6. #6

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    We love these engines. Lots of happy customers like Paul Klager who just won his 10th feature this season with his RK gen4 ZX10. Our set up uses an aftermarket filter with stock stacks and makes as much torque as anything we've ever Dyno'd.Click image for larger version. 

Name:	IMG_7682.jpg 
Views:	44 
Size:	5.2 KB 
ID:	15734

  7. #7

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    Let me take just a moment to clarify a few points.

    All things being equal, Randy's stock motor, running a equal flashed ECU, lets say Guhl.

    What's the topic? Better corner exit power.

    How does one achieve that? To start off you cant just wish it's going to get better, you have to CHANGE SOMETHING.

    Every motor builder out there is throwing cam timing at it to improve mid-range, corner exit power. Same thing Randy has been tying with little success.

    The other common way to improve mid-range on his stock motor is thru modifying the induction trac. In this case designing a set of stacks to increase power in the required RPM range.

    Again, to make a CHANGE you have to CHANGE SOMETHING. Does using a different air filter along with the stock stacks CHANGE ANYTHING???? HELL NO!!!

    Anything what so ever to change the power curve?? To add more mid-range power?? To improve corner exit??? HELL NO!!

    Why??? Because you have not changed anything, it's just that simple.


  8. #8

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    The topic is about success with the Gen 4 ZX10R. We are having great results with this engine using the stock stacks. I am very familiar with pulse tuning and how it will change the RPM at which peak torque occurs. Altering it can also have an adverse affect on power delivery which is why we prefer the smoothness of our choice. We also feel that our target peak torque RPM is being obtained.
    Randy has altered cam timing therefore his engine is not stock it's spec. Exhaust system can also have a negative effect on power range and shouldn't be overlooked. I agree that a tune from Don is Randy's next step if he hasn't done so.
    Here is a video of Friday's event that shows this package isn't lacking power anywhere.

  9. #9

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    Congrats on your great results.

    However end of the day, the stock stacks will never match a set of stacks designed and tuned exclusively for short track racing.

  10. #10

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    Thanks guys, I was just looking for some direction moving forward. My comments about the gear ratio choices should have been at 11:76 we are still lacking bottom end and just kissing the limiter sometimes. At 11:97 we are in the limiter at the flag stand. With a micro I would think you can dial the gearing a bit closer. Not sure if RK uses a quick change and if it is any better on ratio (sounds good in video). I run a 4 into one header 1.625 primaries 2 1/4 collector that I have been using for 8 years on previous generations zx10r. Currently rules do not allow tuned ECU. Western States Rules.

    Thanks for the comments

    Video from a couple weeks ago.

  11. #11

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    Your going to have a hard time getting anywhere with the stock ecu, seems pretty stupid and a nightmare to tech, take that any way you want.... The headers are likely great for top HP but you might want to think about something different to help your issue. Personally I wouldn't get to caught up in gearing at this point, fix the problem then work on gearing.

    A quick word on stacks. The larger the ID, the less low-end and mid-range power their going to produce, that's a given. Now go take a look at your Gen4 stacks, HUGE!!!
    As I said at the beginning the Gen4 is the HP king, that's what it's designed for, that's why the throttle body venturi is so freaking big and why the stacks are the size they are, Peak HP.

  12. #12
    Member TXaggie13's Avatar
    Join Date
    Jun 2014
    Boerne, TX

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    Quote Originally Posted by RandyR41 View Post
    Currently rules do not allow tuned ECU. Western States Rules. ]
    So y'all allow aftermarket intakes, but not tuned ECUs? My club does not allow ECUs either but we also don't allow intakes (100% stock rules). I am curious to know how these motors react to intakes on stock ECUs? Not just 11-15 ZXs alone but I am curious across the board, for all motors in our application. Just looking for a little wisdom.

  13. #13

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    I would say 85% of my customers are simply adding 5psi to the fuel pressure and are more then happy with the results.

    Truth is there's tracks out there that don't allow a power commander so everyone does the flash and no one knows the difference. It's quite really stupid to limit such basic needs, they don't cost much, and it keeps things more even-more above board.

  14. #14
    Senior Member
    Join Date
    Oct 2012

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    Randy, I think your comment about the difference in cars is very applicable. I am amazed by dwarfs and mod lites anyway because the rotating weight of the drive line weighs so significantly higher than the bike the motor came out of.

  15. #15

    Re: Anybody Running Gen4 ZX10R (2011-2015)

    I agree the ECU rule is incorrect, but its what we have. Are People flashing their ECU's, Pretty sure they are, but can't prove it. I think it will be brought up in this years discussions since it is probably cheaper than Power Commander which is allowed. More so than that, You cant tech it, short of doing ecu swaps.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts