197.6whp @ 8250 rpm...NA...

clamping force on MSP clutch is 1350(or something like that) and the non-MSP is like 1150(or something like that) I think. but exedy offers a stage 2 and stage 3($$$$$ for stage 3). But I think the stage one is plenty for this NA build, no?
 
too much increase and you risk burning up the throwout bearing.. I run a 30% over plate which is 1800 lbs based on your 1400 number... and with the clutch disc I use it's good to over 450 ft-lbs of torque. Clutch material matters more in a lot of ways than clamping force.
 
my stocko pressure plate was 1400lbs, CM stage 1 was 1600lbs (which was just a modified stocko i found out)

highest i've heard on a g-series box is 2100lbs (guy in sydney). he's had no throwout bearing problems. he'd go more, but he'd rather the clutch let go than the gearbox.
 
I don't know how you got 1400lbs, but your stock clutch is just the same as what I have and everyone else has
 
i got the 1400lbs from having the pressure plate under a bench press and tested the pressure. i didnt do it, a very very prominant racing clutch maker (builds touring car clutches) in australia did it for me. i was there when he did it
 
I think it's wierd cause it should have been closer to 1150. Yours was even higher than the MSP clutch rating. You Aussies and your different numbers :p
 
yeah could be. the pressure plate was only about 6 months old too. it was replaced under that tsb

and note it's not the clutch rating - it's the pressure plate rating. i will never ever ever look at clutch holding ratings again. from what i've found out it's very subjective and what the plate can "hold" is directly related to the pressure plate clamping force
 
twilightprotege said:
yeah could be. the pressure plate was only about 6 months old too. it was replaced under that tsb

and note it's not the clutch rating - it's the pressure plate rating. i will never ever ever look at clutch holding ratings again. from what i've found out it's very subjective and what the plate can "hold" is directly related to the pressure plate clamping force
Click to expand...

yes I was talking about the set load which is the "clamping force" you're talking about.... either the tester gizmo your guy was using is wrong and overrating the s***, or mazda/exedy is under rating their s***

in short:
under rating = good
over rating = BAD
 
TheMAN said:
yes I was talking about the set load which is the "clamping force" you're talking about.... either the tester gizmo your guy was using is wrong and overrating the s***, or mazda/exedy is under rating their s***

in short:
under rating = good
over rating = BAD
Click to expand...
Or we here in oz could get different stuff???

dunno.

Wouldnt say twiggy's clutch guy is shifty... builds racing clutches for some pretty well funded and well known race teams here.
 
have the graph at my apartment now...and the Excel printout...but I am home until the middle of this week since finals just finished...needed to get the exhaust installed and some other stuff...

graph as well as the vid should hopefully be up by wednesday or so...but I still have the video on my machine...the excel printout will be on though...check the first post of this thread...I will just attatch it there, rather than the middle of page 5 or something...

the curve is extremely peaky though, which is why I am pulling the revs and dialing the band down with the cam gears...the power was around 175whp or so at 7300...then the overlap timing and scavaging kicked in real well and the 20 or so additional hp came in just 1000rpm...it made for a very funny feeling engine...and I would never be happy with that for the street...that steep power curve was further s*** on by the way the clutch would hold the 150lb-ft of torque fairly well, but immediately be put to the test at the higher revs...it seemed to hold on the dyno for me...but when kyle drove it on the track he said it was slipping at shifts after the launch...that will be cured by next weekend also...

I am pretty confident that I can gain area under the curve, albeit with less peak hp...and make the car a little faster than it was in the first place...just need an hour or two on the dyno after toying with it...
 
Installshield 2 said:
haha no way dude...
Click to expand...

Then you going to run into problems soon. You want your internals to hold good...you will need to at least replace the rod bolts.

This is what I found on the side of the road when I blew my last engine...rpms killed it. Yeah, I was running high boost, but the boost wasnt the killer in this one:

TDC will put so much strain on the bolts that they will stretch...

I mean...leaving TDC on the exhaust stroke where the worst stress on the internals is happening.

rodcap.jpg
 
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yeah I was kidding...everything I put into this was ultimately just for the revs...ARP bolts are basically holding every spinning part of the engine down...and nearly every bottom end journal has a sharper tolerance for lubrication to stay as good as possible...

TDC @ exhaust stroke is truely the only thing to worry about at high revs...as long as you have high real compression (by real I mean not the mathematical constant being "static"...overlap bleeds off compression into the exhaust system at some speeds due to scavaging...you can have very high "static" compression, but low "real" compression if your overlap settings are big...)...high compression allows a strong negative force to help with the TDC directional changes...the piston travels towards the head, and with high compression, the precombusted mixture will cause a retarding force that can actually put less stress on the internals even with very high rpm...but obviously only during TDC @ intake stroke...exhaust stroke there is nothing pushing back on the pistons when they hit TDC....and the calculations needed to determine how strong the rods, wrist pins, etc. need to be are directly based on the forces at this point of the engine cycle...as far as revs are concerned, this is the most stressful part of a 4 stroke engine's operation...

as far as SWC cars, I never knew...I was told they could not mess with bottom end dimensions...so rods had to be the same length, as well as stroke/bore...but compression could be increased...I do know though that they were also up around 8k rpm...with some wildly modified intake manifolds...

The proteges were pretty competetive too until RealTime was running the RSXs...I simply assumed they had to be above 220whp, not at bhp...but I could be off...

either way though...there is plenty of room to improve...if I ever get a real job, I will just tear everything apart again and put a 88mm destroke'd crank in it or something...and shoot for 9k...as far as I can tell more power will be tough to get without piston speed...at this point...
 
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