Thread: R&D cam gears
08-04-2010, 04:18 AM #1
R&D cam gears
so has anybody had the chance to fit and test these goodies out yet?
08-09-2010, 04:58 PM #2
I just got back from the river and tested my cam gears.
I hate to even post results since they are not as accurate as I would like them to be, but I know a lot of people want to know about them.
OK, this will be kind of a long writeup but I would rather give too much information than not enough. All my other current mods are in my signature.
I installed the INTAKE SIDE ONLY, @ 5 degree advance. This is the S2 setting. I had planned on doing the S3 setting which includes a 2 degree advance on the exhaust side, but as you will find out when you install them, it is best to take this process one step at a time. This way if I screwed up the timing, I would know exactly which side (intake/exhaust) the problem was on.
Well I lucked out and got it right on the first try. Really I didn't luck out. I spent a few hours on the phone with Bill Chapin of R&D who pretty much walked me right though it. I can feel a noticeable difference in low end, and midrange pull. Throttle response is a bit snappier too. Idle is just a tiny bit different than stock but hardly noticeable at all.
OK now the numbers. Today and tomorrow are supposed to be the hottest days so far this year for STL and I did not make it out as early as I had planned to. The humidity is almost intolerable. It doesn't even feel cool on my face @ 70+ mph down the river. My speed was only .2 faster than my previous fastest down river in MUCH better weather conditions. So take that for what it's worth. I figure I'm loosing more than 1mph due to the heat and humidity today and I still went .2 faster down the same river, but with the cam gears.
I will look and see what the weather will be like in the morning and possibly try and make it out at sunrise. I may also slap the exhaust side cam gear in tonight since I now know I have the timing correct on the intake side.
I apologize, but I do not know my RPM gain from the gears. Since my AEM piggyback system is out for service, I do not have a way of knowing where my RPMs were. Not that it would have mattered much with the drastic change in weather we've had in the last day or so. I know my RPM increased since I was able to go .2 mph faster in worse heat, but I don't know by how much. Pretty sure I am not quite on the limiter yet either but I have to be close. I will know my RPMs maybe this weekend if my AEM system makes it back to me in time.
You can pretty much bet on the expected RPM gains in R&D's instructions being spot on, or even a bit conservative. Kind of like with their boost wheels. They don't overrate their boost wheels either. The numbers are based on real world results.
I want to give a HUGE THANKS to Glen @ R&D and especially Bill Chapin for spending hours on the phone with me on this. With the knowledge I gained, I will do my best to help others out with their installs as they helped me. Here I am just some nobody in the middle of the midwest, and I had the owners of R&D helping me with this the entire way. After all the help, I don't know if there is anyone as committed to our hobby/sport and those guys. They literally eat sleep and breathe skis. I've dealt with many other companies, and am not knocking any of them, but the service from R&D has been exceptional.
08-09-2010, 05:37 PM #3
- Join Date
- Jun 2008
thanks for info--- do a write up of how too install cam gears and make it a sticky
08-09-2010, 07:14 PM #4
The best advise I can give on this install right now is this... sometimes you have to see what it looks like when it's wrong, before you can be 100% confident that you have it right. Hope that makes some sense.
If you guys order them and run into any trouble installing, just post up. I will work on my own install experience write-up later tonight. I think I may go out and drop the exhaust side in. Now that I've felt S2, I want S3. lolol
All that said, this mod is the shit. I say order away. Definitely worth the money. And you are not just buying a $200 set of CNC machined medal gears. You are paying for a good set of instructions (the stock manual is crap) and support, and all the testing that went into these things.
Here are some pointers for anyone who wants to order them right now.
1. Get the cam chain tensioner tool. It lets you put tension on the chain after installing the gear so you can turn the motor over a couple times, get back to TDC (top dead center) and recheck all the indicator marks. It's good peace of mind before you slap the hydraulic tensioner back in.
2. DO NOT TURN THE MOTOR OVER WITHOUT TENSION ON THE CHAIN. If you do you will cause it to skip teeth.
3. You need a set of needle nose vise grips.
4. You need a Sharpie to make marks on stuff so that if you ever loose timing, you can get it back and start all over.
5. When you pull out the stock hydraulic tensioner, the stock gasket will tear, just like the oil pump gasket does when you remove it. R&D sells a really nice replacement gasket that is reusable for the hydraulic tensioner.
6. You may want to also order new crush washers for the little oil tube that connects the block and hydraulic tensioner. I reused mine, and they did not leak, but they don't cost hardly anything so just get them.
7. If you don't have a dial indicator that can reference exact TDC on our motors, you should probably get one. It will make things much easier. If you want to be a wise ass like me, and do it the bum way, with a long screwdriver or extended pen magnet, then it is possible to do it that way, but do it at your own risk.
8. You can run the cam gears without throwing off your AFR much at all. Bolt em in and GO!
What these cam gears, and messing around with cam timing in general offers us, is a way to make more power, without always just throwing more boost at the motor. Less boost is easier on things like the clutch. So we have really turned over a new leaf on our setups. Obviously this is not a new concept at all, but it took a lot of time and testing to figure out what works on these motors and with what setups, and with what gas. I think R&D has really hit a home run with these little things.
08-10-2010, 02:29 AM #5
thank you for your reply and results on this hitman i have ordered mine and waiting on them ant other parts i will update this thread when i have mine on and running, with my results
08-10-2010, 08:11 AM #6
#2 is important. Don't just install the tensioner, make sure it has extended so it will put pressure on the chain.
08-10-2010, 09:49 PM #7
Nice report Todd!
Think the conditions are any worse in STL at the moment than at Mudbug?
08-10-2010, 10:08 PM #8
I will be dropping in the exhaust side cam gear, with 2 degree advance, (S3 setting) probably tomorrow afternoon. I had been avoiding it because of the heat, but I'm making a trip out to my buddy's air conditioned shop. Then I will look for a good weather day this weekend. It's supposed to cool off quite a bit.
08-14-2010, 10:23 PM #9
- Join Date
- Apr 2007
Hey Hitman any update on this?
08-14-2010, 11:12 PM #10
Yes, I have updates. I just hope people don't take them the wrong way. The cam gears are a great mod. However, based on my most recent results, I have come to the conclusion that the S3 setting is a bit too much for people on stock boost. I hope that doesn't deter anyone from experimenting with them.
I really believe it's a trade off situation. If you add a bunch of bottom end, you might sacrifice a little top end, just like with props.
Based on everything I've tested, R&D's recommendations in the instructions are spot on. Seems like they put a lot of time and effort into real world results. I'm all about real world results. The S2 setting is a wicked setup for stock to mild boost. S3 is getting into somewhat more aggressive curves and could require tuning. If not that, then it definitely requires higher boost levels to take full advantage of the timing curve.
This mod is all about cylinder pressure. A given cylinder pressure on an engine will yield a certain HP. There is no getting around it. Doesn't matter how you get there, cylinder pressure directly relates to peak HP numbers.
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