unibody considerations with high power

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Mueller
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unibody considerations with high power

Post by Mueller » Sun Dec 22, 2002 6:48 pm

neutral drops? Image

I never knew they built an automatic 915 transmission!?!?

porsche_914_freak
Posts: 525
Joined: Tue Mar 05, 2002 3:01 am

unibody considerations with high power

Post by porsche_914_freak » Sun Dec 22, 2002 6:58 pm

who said anything about an automatic?

neutral drop is when your in gear, and slide your foot off the clutch petal sideways so the clutch "drops".

Mueller
Posts: 278
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unibody considerations with high power

Post by Mueller » Sun Dec 22, 2002 8:25 pm

"Dumping the clutch" is what you mean...

"neutral drop" is when you have the car in neutral, rev the motor and slam the shifter into gear....only in an automatic
can this be done, which is a good way to ruin a tranny Image

why slide your foot sideways? just let go of the darn thing

what motor? you won't be doing any kind of burnouts with a /4 motor

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Mark the canuck
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unibody considerations with high power

Post by Mark the canuck » Sun Dec 22, 2002 11:45 pm

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Mueller:
<B>"Dumping the clutch" is what you mean...
</B><HR></BLOCKQUOTE>

Yep, you bought the wrong car dude!

914's are for the twisties not the 1/4

porsche_914_freak
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unibody considerations with high power

Post by porsche_914_freak » Mon Dec 23, 2002 2:58 am

we hope to build a strong enough car that it wont mind neutral drops and alot of abuse. do we need to weld tube all around the engine/tranny mounts? how strong is the stock motor mounts anyways? the stock tranny is being replaced by a 915 gearbox and 930 cv joints. but i wonder if the tranny mounts wont rip holes right through the trunk? maybe steel plating?

shawn
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unibody considerations with high power

Post by shawn » Mon Dec 23, 2002 3:16 am

the rubber engine mounts that hold the engine to the bar are not good for sudden jerks. i did a really good burn out in my 914 one day and tore both of those mounts in half and i only have a stock 1.8. so i would look at using something alot stronger.
shawn

porsche_914_freak
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unibody considerations with high power

Post by porsche_914_freak » Mon Dec 23, 2002 4:56 am

ok, clutch dumping it is. i used the wrong words.

how did we get the wrong car? isnt a car only what you make it to be?

Mueller
Posts: 278
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unibody considerations with high power

Post by Mueller » Mon Dec 23, 2002 12:42 pm

I know of a few 3.0 powered 914's running the 901 tranny's that'll dump the clutch to smoke the tires once in a while. no harm.

A lot of it depends on the tires and the motor. My 914 2.0 would spin the tires for about 6 feet, my 3.6 911 layed down 40+ feet of two fat black strips in our parking lot Image
(not good for tranny, but I "had" to show off for a co-worker, LOL)

Stock rubber mounts might not live with this abuse. When I dropped the motor in my last 914, my tranny mounts started to show signs of cracking from the abuse I gave the car.

RANDERSKI
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unibody considerations with high power

Post by RANDERSKI » Mon Dec 23, 2002 10:12 pm

The 915 trans won't handle the abuse for sure. Have considered a bus (late model type 2) trans? It can handle almost anything you can throw at it.

Solid mounts can be fabbed for the 914...if noise isn't an issue and plating the shock towers should be seriously considered.

Unibody construction can be stiffened tremendously by adding a full roll cage that ties in the corners of the car and takes up a portion of the twisting that the motor produces.

I know of half a dozen guys running 3.2+ motors that have overcome many of your concerns. Good luck with your project.

porsche_914_freak
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unibody considerations with high power

Post by porsche_914_freak » Mon Dec 23, 2002 11:22 pm

why wont the 915 tranny handle it? i have been told it will hold 500hp.

i like the idea with the shock towers, and solid motor mounts. a full roll cage might be over my head though Image

what about the rear swing arm mounts?

porsche_914_freak
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unibody considerations with high power

Post by porsche_914_freak » Tue Dec 24, 2002 2:32 am

ok so, stronger motor and tranny mounts it is!
what about the unibody? can it handle hundreds of hp and torque?

this is what we are scared of the most, seeing the motor and tranny fall to the ground in a twist of torque when the tires hook up with traction.

Mueller
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Joined: Wed Jul 11, 2001 2:01 am

unibody considerations with high power

Post by Mueller » Tue Dec 24, 2002 2:44 am

unless you have a monsterous V8 car with huge tires, I wouldn't worry about it too much....and even then, things can be taken care of...there will always be a weak link, just hope it's the cheapest thing to fix Image

RANDERSKI
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unibody considerations with high power

Post by RANDERSKI » Wed Dec 25, 2002 2:43 am

915 Trans is not very cost effective to R&D (Break parts)...if you have the bucks to drop on it go for it. Other wise you'll need to explore other cost effective options. What are your intentions with the car? Track or strip? Rear swing mounts should be ok...most guys will box the rear arms to make them more ridgid though. If you plan on running the car on the track or even on the street with BIG power go for the cage! It will save you some time down the road and possibly your life. Let me know if you decide to go with a cage...I am putting one in our shop's 914 in the next week.



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porsche_914_freak
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unibody considerations with high power

Post by porsche_914_freak » Thu Dec 26, 2002 4:50 pm

our intentions for the car is track, strip and street. i know thts is a difficult thing to do. i figure if its fast on the track its fast on the street. and for the strip just deflate the rear tires a bit Image

basically, take a stock 914, make the rear portion stronger to hold more power, throw some fatty tires on it and install a j ported 13b 2 turbo intercooled rotary engine. then finish it off with suspension, brake and body upgrades.

weight will be the same as stock, only with 4-5 times more horsepower.

the engine is already done, tranny and front syspension of a 911 are sitting in the gurage.

all we really need help with is figuring out what exactly needs to be modified for more strength.

boxed trailing arms, welded up rear shock towers that have welded tubes going to plates of steel on the tranny mounts. solid motor mounts. rubber new tranny mounts. 930 cd joints.

we still need to send the tranny out to get the diff flipped.

what else could be done for more body strength?

why do you say the 915 tranny is no good? i thought it was able to handle more power and abuse?

RacerBVD
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unibody considerations with high power

Post by RacerBVD » Sun Dec 29, 2002 8:47 pm

I have a 914 roller that is already fully caged, and has tranny braces as well!! This could be a good start for you. Email me for pictures!!

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RacerBVD
http://members.rennlist.com/racerbvd/

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