Balance shafts

All technical questions and answers regarding starions, being modifications to maintenance.
JD_Stazza_Brendan
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Post by JD_Stazza_Brendan »

I know first hand that Davidbek95's car runs no BS's, no aircon, no powersteering pump so the only drain on the motor is the alternator. His car accelerates very quick and also runs a decent sized turbo (cant remember specs) also with different diff gears.

It doesnt have a problem buiding boost. Only thing you have to worry about is grabbing the next gear all the time :D
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cheaterparts
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Re: balance shafts

Post by cheaterparts »

4gpwr wrote: I am the bloke who bought the ja starion shell that you were going to race but you could not get enough weight out of i have seen how much pwr your sigma makes and your in house macheing on your cranks flywheels ect but you have seen my eng you have heard it .
i still got that shell and i have dummied a 3000gt eng in it
going down that turbo road myself around the end of the year have to pick up some more bits and all the std cheater stuff will be fitted and it will be a twin cam
good to see some use coming from the JA
how is the JD progressing
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TomVR4
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Re: balance shafts

Post by TomVR4 »

4gpwr wrote:Hey Mr cheaterparts i am not question your abailty I am the bloke who bought the ja starion shell that you were going to race but you could not get enough weight out of i have seen how much pwr your sigma makes and your in house macheing on your cranks flywheels ect but you have seen my eng you have heard it .My motor is built to spin that big turbo up and to take a big ping i need to put the motor under load to make boost if i put a lighter fly wheel lwr diff gears ect it makes my motor more slow to build boost I will stand by saying that the more load the faster the boost by the way i still got that shell and i have dummied a 3000gt eng in it i will bring some beer next time i come past
you keep talking about "load" to spin your turbo, what about the flow of exhaust gases? higher engine speed (rpm) gives more exhaust gases. so wouldn't you want to shape your gear ratio's around reaching optimum rpm quickly and lightening engine components such as the flywheel and balance shafts as to allow the engine to spin freely and reach those rev's faster (and also increase rev range). this qould create maximum torque and power. as rember power (W) = engine speed (rad/s) X torque (Nm) so you can't say that you gained power and lost torque (unless you increase your rpm).

(sorry if this is a bit wishy woshy, but i have been studying all day and i am tired, also when i talk about torque i mean the output torque as measured by the dyno at constant conditions, ie constant load (no friction due to wind velocity on the dyno))
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Cookiemonster
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Post by Cookiemonster »

It's simple. Install bigger balance shafts and drive everywhere uphill. You're car will go awesome.
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Post by FST4RD »

Is there really a reliability problem with the balance shafts?
I think it's more poor maintanence, most people when they do a cambelt change neglect the tiny little belt driving the other BS. So inturn this belt only lasts as long as a standard cambelt and will break and ruin the motor if not changed at all.
My mechanic who deals with alot of Mitsi's said as long as you replace both belts at the same time and regular oil changes (i do my oil and filter ever 5000k's) you shouldn't have an issue.
I had my DASH motor rebuilt not to long ago and didn't bother taking the BS out.... didn't really see the need to.
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thrash
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Post by thrash »

engines with low torque (or all the torque up in the high revs) need heavier flywheels for extra inertia to keep the revs from dropping too much between gearshifts..

lightened flywheels work better with big v8s and high cube diesels that don't find it hard to pull the car from 500rpm onwards..

so you may find that with a lighter flywheel you will show a greater dyno figure, but you may may have a slower et because your gear shifts are slowing you down.. while with a heavier flywheel you show a slightly lower dyno run, but your et doesn't suffer or might even be slightly better..

as far as creating load so your turbo will spool faster is concerned.. working hard is not equivalent to working smart, and is definately not equivalent to getting more work done.. adding more resistance or more weight to the drivetrain (= more weight in the car) means that you will be using the same amount of power that is produced by your engine to move more mass.. so same power.. more load/mass.. the end result the extra work being done by your engine/turbo is being used to move that extra mass, instead of being used to make you move quicker.. make sense?

You'll just end up using extra fuel in the process..

generally, big v8s have low diff ratios because the engines make good torque from very low revs... small 4s have higher ratios to allow them to get to their optimum revs quicker..

so all in all.. it's a balancing act (no pun intended with the balance shafts and all that).. too much load in the diff or flywheel (or any part of the drivetrain) and it'll take you ages to get to your power range.. not enough load at the flywheel and you'll have trouble staying in that power range when you're shifting

and not enough load at the diff will mean your engine will use a shitload of fuel on the highway when you're at a constant 100kph and doing 4.5k rpm instead of close to 3k rpm

I'm not as experienced as a lot of people on this forum, so i'm sure they'll correct me if i'm wrong.. but just my 2 cents :)
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Post by tri26t »

oil pressure gains are what I think was the best
I got out of b/s removal and the comfit of knowing
that there are 4 less bearings to stuff up
I dont really know if power gains are what ppl are after
when removing b/s`s I think its about peace of mind
shit if you were after power maybe putting ball bearings
on your camshaft will do it for you or lightening the flywheel
then running your alternator of there.

oh the thing about boost comming on late could be as simple as
having a large exhaust housing, an .048 will probably give you boost
in neutral, a .063 boost at2600+ a .082 at 3600+ a .100 at 4200+
and so on.could be the turbo was never matched to the vehicles gearing
try a gt-30 BB series turbo (sorry I dont know what your running.

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TD05
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Post by TD05 »

leave them in, it's not worth it, I just like it SMOOTH , I mean I liked it

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