Timing and performance

Discussion in 'Modifications & DIY how-to' started by Cool_____, Jan 5, 2010.

  1. Cool_____

    Cool_____ Banned

    If you have one tooth off on the timing belt (on my car the drivers exhaust cam is off by a tooth....more like only half a tooth), how much does that hurt performance?

    I know on Ben's car he was off a tooth on every cam and it killed his performance. I'm only off by one tooth on one cam.

    BTW do not use a Gates Kevlar belt. I took my old stock belt and lined it up with the Gates and sure enough it lines up for 3/4 of the belt and then the teeth start shifting places. I'm going OEM as Will told me that he had the exact same issue with another Gates belt he had once.

    So wonder how much it's hurting me if any at all? I'm 99% sure that's why I'm throwing the random Camshaft position sensor CEL.
     
  2. integroid

    integroid Supporting Member

    I put the Gates timing belt on my car and King didnt have a problem getting it to line up? There have been hundreds of these installed and I haven't heard of any problems so far.
     
  3. DaveH

    DaveH Member

    How can it only line up for 3/4?

    It's either same tooth-spacing and length or it isn't, right?
     
  4. Cool_____

    Cool_____ Banned

    I'm not asking about the Gates belt in general....I'm simply asking how much this one tooth off could be affecting performance if any at all.


    FYI the Gates lined up PERFECTLY and I hand turned the engine completely at least ten times and every time it lined right back up. Never threw the CEL while breaking in the engine but I never went WOT or over 5 psi boost. On the dyno first couple of light pulls was fine. Then the first serious power pull bam the CEL came on and Robbie got off the throttle.

    However logs showed the car was performing flawless and I told Robbie maybe the CPS is flakey from all the oil I spilt on it and I told him to keep going if the ECU was happy which it was.

    I've isolated the CEL throwing to low gear fast REV instances (like 1st and 2nd where you wind out the gear so fast it stupid).

    I pulled my timing covers to check the timing like Robbie suggested and sure enough one gear is off. I think the belt stretched somehow.

    Called up Will and he confirmed that he has seen the same thing happen on other Gates belts. Some are fine and some are not.
     
  5. Cool_____

    Cool_____ Banned

    Not necessarily if the belt itself stretched. When I line the crank timing mark, the passenger side single ticks line up perfectly to the timing cover and the double marks line up perfectly. On the drivers side the intake cam is dead on but the exhaust cam the double ticks don't line up with the double ticks on the intake cam. Only one tick lines up. I've played with it enough to know that one tooth is more than that little 1mm that is between the ticks hence me saying it's 1/2 or 3/4 of a tooth off. One tooth is wider than the two ticks on the cams.
     
  6. integroid

    integroid Supporting Member

    I have hit full boost the first 100 miles and King had to check the timing belt again and said it was fine. I personally havent had any problems with mine but that is not what this is about.

    Maybe one of the mechanics can chime in and give their insights on how one tooth would affect your performance.
     
  7. Cool_____

    Cool_____ Banned

    Yeah I could have a flaky belt. So I just went OEM since the dealership is right down the road and I got the belt at $103.

    I doubt any of the mechanics would know for sure but hey if they do GREAT! Figured some extra input from tuners would know. I like to over research and get input from EVERYONE vs input from one or two people ;)
     
  8. siegelracing

    siegelracing Registered Vendor<br><b><font color="#666666">bion

    If you count the teeth on that gear and divide by 360 you'll get the number of degrees off that it is. Even 2 degrees makes a power difference... 5 degrees is probably "perceptible" to the driver...

    Siegel
     
  9. Cool_____

    Cool_____ Banned

    I did not know that Scott.

    So lets say there are 50 teeth. So 50 / 360 = 0.13888. So does that mean if that gear was off by 1 tooth it is off by 13.8 degrees of timing? 2 teeth is 27.7 degrees off and so forth?

    That's cool math right there.
     
  10. slowdriver

    slowdriver Banned

    On SOHC engines, 1 tooth is a tremendous difference.

    The only DOHC engines I've seen with one cam off typically was off by 3 or more teeth. It was obviously running like crap, barely drivable.

    Lots of people who have higher mileage cars like to spend as little as possible and that is usually a gates timing belt. Mainstream products like Honda/nissan/toyota/ford/gm have no issues as there are tens of millions of them that run gates belts and gates did proper R&D before selling the product seeing as how they knew they would sell so many, thus many mistake would cost them lots of .

    subaru on the otherhand, SOA is lucky to sell 200k cars a year so the market is small but still present enough for gates to rush in some belts.

    The loyale timing belts are trash. They might last 15~25k miles at the most. Most of the SOHC belts are ok enough that theres never a problem. I've personally seen a few DOHC and EJ205/255/257 belts that have issues like Coolrex is having. But 90% of the time the DOHC belts are ok enough like the SOHC belts.
     
  11. Cool_____

    Cool_____ Banned

    Heh OEM for the win when it comes to timing parts.
     
  12. slowdriver

    slowdriver Banned

    For sure.
     
  13. integroid

    integroid Supporting Member

    I have heard it a few times that the Gates makes the belts for a few of the aftermarket companies that sell the Kevalr belts. Like slowdriver has said, I have used Gates belts with great success on many cars and never once had a problem with their belts. These were more mainstream cars though....I thought the Subaru used Gates belts as well on certain models?
     
  14. Cool_____

    Cool_____ Banned

    Maybe mine is a fluke. Regardless it's not right and a solution is to be had by getting OEM.

    Wonder if I need to get retuned? Hmmmmm maybe I'll go ahead and up the wick sooner than planned and boost this thing like intended.
     
  15. integroid

    integroid Supporting Member

    LOL....Yeah, the boost comes up so quick on my car right now that it is impossible to keep out of it. I changed oil at 500 miles and has been hitting short periods at 22psi since. Should have 1000 miles by the weekend and hopefully the new turbo setup soon.
     
  16. Cool_____

    Cool_____ Banned

    Sweet. I'm at 1700 miles on the new engine already. I'm getting full boost by 3800-3900 rpms and it's SWEET. Punched the car yesterday when it was 19 degrees out on the way to work and it snapped the rear so hard it scared me for a second. Then there was a ear to ear smile on my face.

    I think I can hit 450 on a Mustang once it's all said and done after I get rid of a few restrictions.
     
  17. slowdriver

    slowdriver Banned

    I have not seen an OE gates part on any subarus...SOA may have used gates for belts some time ago, same as using Purolator and Honeywell as filter makers for the American market only. As of right now there is not a single piece of gates rubber found on any factory vehicles or in a parts department with OE Subaru parts.


    However, the normal accessory drive belts that gates makes are good as long as you get the correct size. No problems to report there.
     
  18. Cool_____

    Cool_____ Banned

    That's kind of a moot point since those are hugely adjustable.
     
  19. slowwrx

    slowwrx Supporting Member

    1 tooth will make a difference on the dyno but you might or might not feel it, two teeth you will feel and its usually like the car hits a wall power wise
     
  20. Cool_____

    Cool_____ Banned

    How much of a difference? Are we talking minimal 5 hp or more substantial like 15 hp?
     
  21. slowwrx

    slowwrx Supporting Member

    atleast 15hp
     
  22. Cool_____

    Cool_____ Banned

    Nice.....can't wait.
     
  23. slowdriver

    slowdriver Banned

    I'll agree to that but most of the time the 'next size up' is right at the end of the adjustment and the 'next size down' you cant even get it on w/out prying and rotating the engine over at the same time.
     
  24. Cool_____

    Cool_____ Banned

    ^^That's very true.
     
  25. slowdriver

    slowdriver Banned

    !!!!!!!!

    Coolrex needs to hurry back to the dyno after the new belt gets installed!
     
  26. Cool_____

    Cool_____ Banned

    Haha just got off the phone with the tuner. I think I'm gonna go ahead and get the rest of what I need and unleashing the potential. The biggest wait is something that I have no control over....it's gonna help both me and Kokopelli :naughty:
     
  27. nicad

    nicad Yes I am a troll

    which you do NOT want to do. very bad for a belt. rolling belts on is very damaging to their longevity
     
  28. gotsol

    gotsol Active Member

    are you tired of messing with this thing yet?
     
  29. Cool_____

    Cool_____ Banned

    Not quite....everytime I mess with it it makes more POWA! LOL.
     
  30. Mike@TTR

    Mike@TTR Active Member

    Ben's we actually say around 20-30 hp or more on the VF-39 when Doug and I compared his graphs to other vf-39 cars. On a bigger hp car I think the difference is more than likely a percentage of power. His car was hitting a wall. Kind of like the wall Liquidforce was hitting with the wrx cams.
     
  31. Cool_____

    Cool_____ Banned

    Yeah but Ben was off a tooth on all 4 cams from what you told me. I'm off on only 1 cam.
     
  32. slowdriver

    slowdriver Banned

    Truth.

    However, subaru didnt believe in that statement with the 2008+ and 2009+ Impreza/Forester AC belt. You have to roll that one on HARD CORE. The belt comes as a kit with all the tools needed to install it, minus a knife to remove the old one, a 22mm socket and breaker bar to rotate the engine.

    They also tell you that you cannot reuse that belt, or the tools...which is a huge line of BS.


    And again, 1 tooth off on all 4 is much more different than 1 tooth on one cam.
     
  33. Cool_____

    Cool_____ Banned

    Indeed. In all honesty I don't know how ben's car even ran with it being 1 tooth of on all four cams. If the crank was aligned his CPS's should've been triggering the crap out of the CEL. Shoot mine is now if I rev it hard in a low gear.
     
  34. nicad

    nicad Yes I am a troll

    wow. that's retarded.
     
  35. siegelracing

    siegelracing Registered Vendor<br><b><font color="#666666">bion

    I don't know if you can post the Subaru manual or the Alldata page for the '08+ AC belt but it's hilarious.

    It really shows the guy cutting the old belt and then you have to install the "tool" (a little plastic "ramp") to roll the new belt on...

    Crazy.

    Siegel
     
  36. Cool_____

    Cool_____ Banned

    ^^^That is funny.
     
  37. JDM-STI

    JDM-STI Member

    I'm gonna have to go look at the tensioner set up on our 08 STI versus my 05. I've never noticed any differences but at the same time I've never really studied it either. Not sure why much if anything would have changed...:unamused:
     
  38. slowdriver

    slowdriver Banned

    The instructions that come with it....funny. I had some guys want me to do some. I was like "WTF is subaru thinking?" :rofl:

    You will not find a tensioner there! Its odd....:pssh:
     
  39. Cool_____

    Cool_____ Banned

    HUH? So the A/C and Alternator tensioners are non-existant on the 08+? What was Subaru thinking?
     
  40. slowdriver

    slowdriver Banned

    just the ac one. The alt still adjusts.

    You can get the LGT belt, 05~09 and all the tensioner parts and blamo you've got the old system again.
     

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