Clutching SC apex Advice

[Barry Barton]

Hi Guys
Was told that I needed to reclutch my apex with heavier weights or I'LL OVER REV the sled . I only put on a stage 1 supercharger and I know very little about clutching but I was told that if u want to get the best out of the sc u should reclutch for down hear and up in the mountains. Some advice would be greatly apreciated and what are the best weights to use.
thanks

 

[shawnmcgr]

I just added weight to the primary by replacing the stock weights with Daltons. They are easy to adjust on the hill. Other than that I've done zip. I'm sure there are other adjustments I could make to improve my clutching. We'll see if I find time this season.

I'm back from vacation so I'll give you a call this week to see how your install is going.

ttyl Shawn

 

[new_nytro]

Hi Guys
Was told that I needed to reclutch my apex with heavier weights or I'LL OVER REV the sled . I only put on a stage 1 supercharger and I know very little about clutching but I was told that if u want to get the best out of the sc u should reclutch for down hear and up in the mountains. Some advice would be greatly apreciated and what are the best weights to use.
thanks

Unless you are ~Rowdy~ I wouldn't expect a decent response to this question.

 

[shawnmcgr]

MY response wasn't decent....man tough crowd!?

Daltons will allow you to pull weight out for you mtn trips and add back in for trail riding at lower altitude.

Or you could turn down your boost at lower altitude and adjust your fuel box. You would have to keep track of your fuel box settings for high and low altitude. Turning down the boost at low altitude will avoid the need for higher octane as well. You could run 8psi on the trails and 10-11 in the mtns.

Either way your going to have to make some adjustments to your fuel box for large changes in altitude.

 

[new_nytro]

MY response wasn't decent....man tough crowd!?

Daltons will allow you to pull weight out for you mtn trips and add back in for trail riding at lower altitude.

Or you could turn down your boost at lower altitude and adjust your fuel box. You would have to keep track of your fuel box settings for high and low altitude. Turning down the boost at low altitude will avoid the need for higher octane as well. You could run 8psi on the trails and 10-11 in the mtns.

Either way your going to have to make some adjustments to your fuel box for large changes in altitude.

Sorry, I didn't mean that your response wasn't a good one. I was just suggesting that if it was ~Rowdy~ asking the question there would probably be 50+ posts in this thread with guys volunteering their services including free parts and labour. But if a dude has a valid question there are few responses, and most of the responses are will include some form or sarcasm or brand bashing.

 

[shawnmcgr]

Sorry, I didn't mean that your response wasn't a good one. I was just suggesting that if it was ~Rowdy~ asking the question there would probably be 50+ posts in this thread with guys volunteering their services including free parts and labour. But if a dude has a valid question there are few responses, and most of the responses are will include some form or sarcasm or brand bashing.

I hear that!

Maybe Barry you should get Rowdy to ask?

 

[MRFUSION]

Daltons are a good choice, they have 66gr, 70 and 74 gram weights you can choose from. I run the 74gr with the Blue White Blue spring, and 14.5 rollers. I am running more boost and a turbo setup though. I would think with the stage 1 kit your boost is around 10psi, maybe the 66gr weights with 17.2 rivets in both holes should pull you down. Might want to beef up the secondary spring with a EPI purple or something, you will have to change your settings as the tabs are different but lots of guys using them. Good luck. Shad

 

[Barry Barton]

Hi shawn
the install went well took my time and had very little trouble. Broke a bolt off torking it down on the right side cover but it came out easy lucky me. fired the sled up this weekend and it looked good no leaks but a big quetion does the sc always have such a high pitch wine and is this normal. When u ajust the sled with the remote unit that is pluged into the sled all those fance lights mean nothing is their a book or do u just raise it up or down depending on the sound of the sled or the feel of the sled or engine.

 

[shawnmcgr]

Hi shawn
the install went well took my time and had very little trouble. Broke a bolt off torking it down on the right side cover but it came out easy lucky me. fired the sled up this weekend and it looked good no leaks but a big quetion does the sc always have such a high pitch wine and is this normal. When u ajust the sled with the remote unit that is pluged into the sled all those fance lights mean nothing is their a book or do u just raise it up or down depending on the sound of the sled or the feel of the sled or engine.

I'll have to fire mine up and listen to it - but ya I think it did. You have to keep in mind that a super or turbo are spinning at huge rpms, well over 100,000. I can hear a high pitched whine from the turbo on my truck every time I come off the throttle - and it has an air box to quiet the air intake down. Turbo and supercharged sleds have simple air intake so the intake noise is greater. I think I've just gotten used to it.

Check to make sure you have no rubs on your belts and pulleys. I had an oil line rub on mine after initial install.

Adjusting the fuel box is a bit of an art. You really need an Air/Fuel gauge to do it properly. Some guys might be able to tune by the "feel" of the motor", but I cannot. Ya, sure I know lean back fires and rich bog but I don't want to trust a $5k motor to just that. I've attached a few files I have collected which help explain the fuel box adjustments.


I'll dig up my settings when I'm at home. But generally I think I left altitude, acceleration, and accelerator pump as recommended by MPI. I have Green "idle" leaned out as far as it goes (0.5 I think) and I have used boost and main jet to tune the top end and mid range. I adjusted towards a much higher boost setting and kept the main jet setting fairly low. This helped with the mid-range lean spot.

ttyl Shawn

 

[shawnmcgr]

Here's a vid of mine the first time I fired it up. Near the end you can hear some of the whine. You can see where I've mounted boost gauge and afr gauge. Good example of lean af readings as well. The gauge reads up to 15-16 which is way lean but the motor still sounds fine - good reason to have a gauge.

IMGP0130 - YouTube

 

[Barry Barton]

Hi shawn
thanks for the info your sled sounds the same as mine but I only have my sled at 5psi it looks like yours is pushing 10 the information is very close to my sled but I picked up the information from Darren at e&s motor sports. He has been working with mpi turbos and sc for a few yrs and is willing to help anybody if u need to pick his brain. He also gave me some good information on clutching from springs to run to weights and everything else if u need anything just call him.
Thanks

 

[mike booooast!!!]

hey there, i dont mean to brage into this convo, i recently picked up a s\c apex and im in the means of doing a one over on it so i dont ge any trip ruening problems this winter, i believe it runs 8psi depending on elevation, are these superchargers tunable for boost like you can on a turbo? or are they constent boost depending on elivation and rpm? thx mike from alberta

 

[Barry Barton]

The boost will stay the same and the only way u can increase the hp is to increase the octane, much safer than a turbo because u forget to dial the boost down on the turbo when u come down u can blow the engine. If u are running 8psi u should run some av gas or racing fuel or u could pre ignite the engine and thats not good.

 

[shawnmcgr]

Yes and no. To change boost levels you need to swap pullies or dump boost with a bypass/bov. Any time the boost level changes you need to adjust your fuel supply. Your fuel box likely has a boost sensor but this just changes the fuel for one mode on the GEMS (I'm assuming your running a GEMS).

I found, when running 5psi pullies that my boost levels would vary with altitude. For this reason I run 10 psi pullies and limit my boost to 8psi with MPI's By-pass/BOV. It's also the max hp I feel comfortable running through stock drivers and suspension.

The rate the charger spins is fixed to the motor rpms so it cannot speed up to maintain boost as the air thins out at higher elevations. So gaining altitude results in less boost. This is one of the benefits of a turbo, a waste gate can be used to maintain a constant boost level at all elevations.

 

[Barry Barton]

Yes and no. To change boost levels you need to swap pullies or dump boost with a bypass/bov. Any time the boost level changes you need to adjust your fuel supply. Your fuel box likely has a boost sensor but this just changes the fuel for one mode on the GEMS (I'm assuming your running a GEMS).

I found, when running 5psi pullies that my boost levels would vary with altitude. For this reason I run 10 psi pullies and limit my boost to 8psi with MPI's By-pass/BOV. It's also the max hp I feel comfortable running through stock drivers and suspension.

The rate the charger spins is fixed to the motor rpms so it cannot speed up to maintain boost as the air thins out at higher elevations. So gaining altitude results in less boost. This is one of the benefits of a turbo, a waste gate can be used to maintain a constant boost level at all elevations.

Hi shawn I thouht that a sc keeps its boost on the way up a climb but makes 10% less power because it takes power from the engine not the exhaust . WHAT IS A WASTE GATE and is this the bov valve with the spring tighted up so u don't lose boost.

 

[shawnmcgr]

A waste gate is a valve on the exhaust side of a turbo that lets exhaust gases bypass the turbine (exhaust) side of a turbo so it does not spin up the compressor side too high and build too much boost. This effectively reduces the load on the motor, it's keeps the load on the motor balanced for the amount of boost required. As a super does not have this it's always compressing the same amount of air for a given rpm level. If it's providing too much boost (part throttle) then it either backs out through the charger (a chuffing noise) or it's relieved by a blow-off or by-pass valve. So a super is going to be less efficient at part throttle as it's compressing (working) and the the work is pissed away. But it's this compression that is being thrown away that makes their throttle response so good. The boost is there waiting you just have to open up those throttle bodies!!!

Hope that helps,

Shawn

 

[Barry Barton]

Hi shawn
Just got my apex out of e&s checked out well I missed a few things on how tight they had to be but other than that no extra work or parts needed. Talked to darren and asked weather a turbo is faster or climbs better than a sc and he said he has compared the sleds and their the same one is no better than the other. The one thing he said is the sc is much faster out of the hole but other than that they are the same.While I was their I picked up a shock wave for my secondary and this way I can change the rpm for down here or up in the mountains in about 2 min so this will also help when I start to climb at higher altitude I can change the load on the engine very quickly and have the sled run at peak performance. The bonace I got is mpi sold me a stage one sc with a stage two air box so this should help me by keeping the air a lot cooler going into the engine and i'm not sure if this will help the performance at all. Chow

 

[shawnmcgr]

Ya, I've heard nothing but good things about Darren. I may drag my sled up there to have E&S install a head shim so I can stop running av gas. I've also thought about getting a Shock wave but I've got my clutching close. I had mine out today....it was nice to feel that pull again!

 

[wilmot]

What wasn't tight enough?

Hi shawn
Just got my apex out of e&s checked out well I missed a few things on how tight they had to be but other than that no extra work or parts needed. Talked to darren and asked weather a turbo is faster or climbs better than a sc and he said he has compared the sleds and their the same one is no better than the other. The one thing he said is the sc is much faster out of the hole but other than that they are the same.While I was their I picked up a shock wave for my secondary and this way I can change the rpm for down here or up in the mountains in about 2 min so this will also help when I start to climb at higher altitude I can change the load on the engine very quickly and have the sled run at peak performance. The bonace I got is mpi sold me a stage one sc with a stage two air box so this should help me by keeping the air a lot cooler going into the engine and i'm not sure if this will help the performance at all. Chow