superjet.1

im in the process of replacing my t-belts and front seals is it possible to not hook up the counterbalance belts and just leave them in place or will this cause problems. <img src="confused.gif" border="0">

tazman

Here read <a href="http://forums.rennlist.com/scripts/rennforums/ultimatebb.cgi?ubb=get_topic&f=18&t=000394" target="_blank">this</a> .

superjet.1

more interested in leaving shafts and components in vehicle but just not utilizing them is this a problem or can it be done

Russ Murphy

You know, I'd be interested in the answer to that question as well.

Andrew

if you leave them in you should find a way to "lock" them so they don't start to spin freely. just a thought.

Luke

"just taking off the belt and leaving them in there is a bad idea. It will make the engine rough as hell. Because the harmonis will turn them but out of order. Just ask a mitsubishi 4G63 owner (Which these shafts are designed after, yes porsche bought the design from mitsubishi) So the only way is to remove them.
" -p951s

944Steve

I've been researching the same thing and it was being promoted to me by Huntley.

I just finished reading a short book on the history of 924 / 944 racing including several Lemans attempts.

The author explored this topic and found that the serious racers with factory help experimented, did get an extra 4 to 5 HP but all the small stuff around the engine broke...making the power not worth the loss of reliability.

Unless you're building a 25 to 100 hour full race engine, I came away deciding not to go there.

Regards,

Steve Doolittle

TCarrera

Jet 1,
We have run our engine for 4 years now with the balance belt removed and the shafts in place.
I was told that the vibration that the shafts are intended to remove takes place at around 3500 RPM yet we have not noticed any extra vibration at any RPM.
If you are driving at that RPM and do not vary from it, the vibration can cause damage. I don't know about you but in our racecar, the engine never sees 3500 RPM but for a split second.
We haven't had any parts fall off or loosen either, but we check all hardware and fastners on a routeen basis as all race cars should.
I agree that this is more intended for race only applications and that you are more likely to operate the engine for extended periods of time at the critical RPM. I would not recommend it for daily driven street cars.
Mike at LR

superjet.1

well i guess ill be the guiney pig im going to remove the belt and lock the shafts in place just to be shure and give it a go.hope all goes well

Danno

Hey make sure you put in dyno runs before and after disconnecting your balance shafts so we would know what the gains are. You can even do them within an hour of each other to reduce variables. Do one run, remove the belts, tie up the pulleys and do the second run.

I may even... sponsor you for that... heh, heh..

superjet.1

i have a g-tec ill try and get the runs several with and several without with a soft launch.i live in castaic california if anyone knows where a good dino shop is please answer back.thanks

Danno

I doubt you'd be able to see a difference with the G-tech, which only gives you a peak-HP reading, not a graph. Doing 5 runs in a row, my G-tech gives HP variations of about 10%. At least with a graph, you may be able to show that the balance shafts are worth a certain amount of HP across the entire RPM-range (or more in the upper-RPMs).