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> Hey Bill Berthgo, gotta question for ya!, oh yeah, made 590HP at the chassis dyno today
byndbad914
post Oct 20 2007, 04:19 PM
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Bill -whattup dood. Hope things are well. Anyway, what were the gear ratios and stock diff ratio for the 930 again? I seem to have lost my excel spreadsheet where I had them saved for car mph calcs.

I made ~590HP on the chassis dyno today, and that seems high to me frankly and especially at a mile-high altitude, so I think I better check the gear ratios. The total may not be 1:1 like they expect out of a 4 speed and I think between blowing the tires off on the dyno (I got a 1300HP spike on pull 1 (IMG:style_emoticons/default/drunk.gif) ) and I could smell rubber after each pull, so I just blow those 12" slicks off and then the dyno has to chase it and gives bogus numbers maybe.

OR the original engine dyno was wrong at 525HP. Sumtin' ain't adding up... but I would be happy with 590HP at the wheels if that is for sure (IMG:style_emoticons/default/laugh.gif)
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RoninEclipse2G
post Oct 20 2007, 04:24 PM
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coming loose on the dyno and burning a touch of rubber doesn't sound too odd at that kind of power. my friend John's supra was making a hair over 600 and we had to sit on the back end to keep it down.

you could be in the wrong gear as well but the symptoms sound about right to me, especially in something as light as the teener
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LvSteveH
post Oct 20 2007, 04:45 PM
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This is what I have in my file for 930 ratios


Final Drive: 9:38 (4.22)


Gear
1 (2.250)
2 (1.304)
3 (0.893)
4 (0.625)
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byndbad914
post Oct 20 2007, 11:24 PM
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Thanks Steve. Those numbers look familiar!

Erik - I agree that the tires may want to blow off, but I sincerely doubt that I am making that much power given my flywheel horsepower on an actual engine dyno was significantly less at 525HP at ~ sea level (Yorba Linda, CA). The shop had a Supra they had the same problem with - figure about 1000HP but could only get up to just over 600HP readings with four guys hanging off the back.

One issue is my car is soooo low I had maybe 2" between the bottom of my chassis and the dyno, so the straps are pulling almost straight back, not down, and I have ran out of grip with other cars as well. But I expect somewhere around 425-450 rwhp at a mile-high now, not almost 600.

This is what I hate about chassis dyno numbers, unless everyone tests on the same dyno with the same correction factors and so forth, the numbers can be really bogus. I asked them to re-cal their machine and explained why and they agreed they may have messed something up trying to run the Supra on it yesterday.
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LvSteveH
post Oct 21 2007, 07:45 PM
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I say you roll the cost of an altitude compensation device into your moving expenses to reclaim that 90hp you lost moving to Denver.

Just throw a supercharger or turbo on there and you'll be good to go. Good thing you built your motor with 8.0 : 1 compression (IMG:style_emoticons/default/laugh.gif)
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wbergtho
post Oct 21 2007, 10:51 PM
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590HP? I've got some catching up to do. That thing must be a wicked fast car! If I remember, this car is a tube frame monster...correct? How about a few pics? I just upgraded my valvetrain with LS7 lifters, Scorpion roller rockers, fresh heads, a slight bump in compression, and a slight bit of extra porting on my already CNC ported heads and may be making 520-530HP now. It was dynoed 2 years ago at an even 500HP. It pulls noticably harder after the upgrades. I dropped a valve, and decided to make a few improvements before slapping it back together.

The gear ratios are as posted.

Glad to see you are still having fun and searching for more HP! Lets be honest, you never have enough. Once you get 600+, you'll want 650HP...and so on.... I think 500-550HP is about all a 914 should really have because you start to exceed the absolute limitations of the chassis. If more HP is desired...like 700-1000HP, I think a more purpose built and more modern design suspension and chassis would be in order...like an Ultima GTR running a 1000HP twin turbo LS2 or LS7. I have actually fallen in love with the RCR Superlight Coupe. Can't afford it...but it looks better than an Ultima. It looks kind of like a Lemans protoype endurance racing car...like a Porsche 956/962. Check it out.

Bill


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Attached File  RCR_Superlight_Coupe.bmp ( 234.43k ) Number of downloads: 41
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byndbad914
post Oct 22 2007, 02:42 AM
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Hey Steve - the dyno here actually claimed about 90 MORE hp so maybe the move was a good thing haha. There is something wrong with their calibration me thinks.

So Bill, not to worry. I still believe the engine to be at 525HP. And yeah, it is full tube chassis now front to rear and stiff as hell. No more flex makes a big difference on the track I can assure you. Put stiff springs on and you feel it v. having the weakest spring be the torsion in your tub (IMG:style_emoticons/default/laugh.gif)

I didn't know you dropped a valve actually. Damn, between that and the clutch issues... gotta be disheartening to say the least. I get fed up with this car on a regular basis, but then get it back together and blast down the street and remember why I bother :werd:

I have been quoted more than once saying, "Nobody told me it would be easy, but they also never told me it would be so damn hard!"

Going to the shitty racetrack out here on Thursday and gonna see if I can get one good track day out of it since all the changes - had snow on the ground this morning (80deg yesterday at the dyno, snow today, freakin' weird here in Denver area). I spent all my time fixing and tuning this year since the whole reconstruction last November. Got new wheels and they really make the car IMO.

As requested, some pix I took a couple weeks ago after getting the wheels and new tires on 16x10 front and 16x11 rear with 10" and 12" tires.
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byndbad914
post Oct 22 2007, 02:43 AM
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I hate how the wing looks, but it is a necessary evil. The air cleaner and wing just kill the lines of the car, but here you can see the 930 turbo brakes/rotors pretty well and will hopefully aid in keeping them cool
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jimkelly
post Oct 22 2007, 09:40 AM
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that thing is nice - jim
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jhadler
post Oct 22 2007, 04:31 PM
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Okay Tim, you HAVE to come out to our TT events next year.

After all, what's 500+ HP if you can't use it???? (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif)

Our TT event this last Saturday was the best all year!!! Truly fantastic...

-Josh2
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byndbad914
post Oct 22 2007, 07:38 PM
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QUOTE(jhadler @ Oct 22 2007, 02:31 PM) *

Okay Tim, you HAVE to come out to our TT events next year.

After all, what's 500+ HP if you can't use it???? (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif)

Our TT event this last Saturday was the best all year!!! Truly fantastic...

-Josh2

Josh - I honestly completely forgot that you guys were going out last weekend. My friend's parents are in town and he wanted to go to the dyno with pops, and then that evening I took his dad with me as my realtor that races rocky mtn vintage invited us to their end of year dinner and car exhibit.

I am loaded and ready to head to Pueblo this Thursday with my buddy and a couple of his friends for an afternoon of general mayhem (IMG:style_emoticons/default/shades.gif)
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