drivetrain problems w/ v8, driveshafts and cv joint problems Options

[army dude]

I have gathered a nice collection of pics and saw a picture from underneath the car looking at the tranny and shafts. I know the drivetrain has been pushed bach an inch and a half but the shafts look like they really are angled badly. What problems arise cause of this and what can I do to strengthen the shafts or cv's? Upgrades?
Thanks!
Ian in Iraq

54 days till stateside
59 till I drive

[Mueller]

What problems?? It's not an issue of angle, these kits have been sold for 20+ years with the transmission moved back like that...it's more of a problem once you reach a certain HP/torque level

Renegade Hybrids sells an upgraded axle/CV assembly....
Renegade also sells the majority of all V8 kits...not sure at what HP/torque output one "needs" the beefier stuff at but they would be a good place to contact.....

[TonyAKAVW]

The reason the axles look like they are at an extreme angle is that because the car is on a lift, the rear suspension is at its maximum extension. When driving I'm sure that they aren't so steep. Moving the transmission back an inch and a half is probalby not going to angle them badly enough to do anything. And Like Mueller said, these are proven over and over again to work.

-Tony

[army dude]

So at what hp is it recommended to do an upgrade? I don't remember where I saw it but I think somebody used bus shafts and cv's. I plan on around, or hope , no more than 400 horse. I have an engine waiting to go in and I used to run 10.15s in the quarter in my 64 Chevy Nova II SS. It has about 480 horse and I plan on brining it down for the street. Your thoughts??

Ian in Iraq

[Mueller]

QUOTE (army dude @ Mar 15 2006, 10:13 AM)

So at what hp is it recommended to do an upgrade? I don't remember where I saw it but I think somebody used bus shafts and cv's. I plan on around, or hope , no more than 400 horse. I have an engine waiting to go in and I used to run 10.15s in the quarter in my 64 Chevy Nova II SS. It has about 480 horse and I plan on brining it down for the street. Your thoughts?? Ian in Iraq

the "correct" method would be getting the "good" stuff right at the start...........

do it right or do it again (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif)

the stock stuff can work, but if you plan on beating on the car, something is going to break........

[army dude]

I fully agree on doing it once and doing it right. I am trying to do my homework and get the experience of the v8 community. I am not in the mood to spend money twice. Any thoughts here only go into my car. So then, is Renegade the best place for these upgrades or is somebody else better? I remember when Renegade came out with the conversion and I still have the article with both the 914 and 911 featured. That is what hooked me. I also am aware of the short comings of the stock tranny. That too will be dealt with.
Ian in Iraq

[Mike T]

I did my V8 swap with the help of the guys here. Lots of help and pictures here. Thank you all.

Here is a picture of the axle angle that resulted in moving the drivetrain approximately 1.5" back on my V8 swap.

Mike T.

[lapuwali]

HP isn't what kills gearboxes and axles, it's torque. A higher revving 300hp 305 would do less damage than a lower- revving 300hp 350, and the 305 would make less torque. In addition to the axles problem, one chronic problem with the V8 guys is the fact that the gearing in the 914 box is so short. 70mph = 3500rpm in top gear. The stock first gear is basically useless (so it's often removed to make a 4-speed). Taller final drives are basically not available (not tall enough, anyway). So, either taller gears in the box itself (which are available, but hard to find and expensive), or a different gearbox, are generally used. Building a V8 that's meant to rev rather than be a stump-puller is also very helpful.

I've not seen in done, but I personally think something like a 289 Ford would be better suited to a 914 than a 350 Chevy crate engine. Run a DIS ignition to solve the distributor problem (dizzy will hit the firewall), and tune it to make 250-275hp with 250ft/lbs, and you'd have a killer 914 V8.

[ClayPerrine]

There is also a solution that uses 944 turbo CV joints for a 5 lug. They are a lot bigger and stronger than the stock 914 CV joints.

I am running 944 cvs on my 914/6 conversion. They work fine.

Sorry I don't have it handy, but if you search, you should find the thread on this.

[Porcharu]

QUOTE (lapuwali @ Mar 15 2006, 11:12 AM)

In addition to the axles problem, one chronic problem with the V8 guys is the fact that the gearing in the 914 box is so short. 70mph = 3500rpm in top gear.

It doesn't hurt anything, just wastes gas and is annoying. We have all just gotten very used to having overdrives on our cars.
Take a ride in a stock HiPo car from the 60's - it will cruise at 3500+ at 65-70 with 4.11's (or 4.56's) it's worse. My friends old dead stock (perfect restoration) Hemi Bellvideere (sp) would float the valves in 4th gear at a little over 110.

[BIGKAT_83]

On a stock 901 transaxle with a 195/60/15 tire 3500rpm is 80MPH not 70.

The transaxles are easy to regear there was a H gear that sold here not to long ago for $200. If you have a good transaxle $200 plus a gasket set would be all it would cost. With this at 3500 rpm you would be running 100 MPH

Bob

[byndbad914]

Ian - another possibility is this. You can get late model carrera outer hubs and buy turbo axle assemblies with the stub axle "built in". Jim at Patrick Motorsports sells some simple little aluminum spacers to make that combo work with the stock 914 wheel bearings.

Then at the inner CV, I would guess that an adapter for 930 size CVs would exist (though you would need to research that a little). With the rear offset you have, the CVs are already "stretched out" a little, so the spacer should fit in there, not bind, and maybe relax the CVs a little.

I have the late outers with turbo axles and the spacers in mine and it worked perfectly. I have a 930 trans and I made some spacers to relax the CVs a little (why I don't know about an adapter as I have the bigger trans already).

Also, depending on what kinda torque you put out and how hard you drive, the 901 may not make it. I have 438 ft-lbs in my V8. If you go with 400+ torque, just skip the 915 and go 930 as it is about the same $$ in the end and WAYYY stronger.

[army dude]

Awesome info guys!!

So if I go with the 930 trans what can I expect out of it with a "tall" gear? I am sure its a little pricey but I only want to do it once. Will I top out over 120 or more?

[Andyrew]

Your factory 901 trani will top you out slightly over 140mph.

The 930 box you can put whatsoever gearing you want in it.. Top speed is not your main concern.

Your main concern is the rpms' at 70mph..

H gear will help..

But that v8 box could push the 914 just fine at 1.5k rpms at 60mph... Finding a box that could do THAT would be awesome.


FYI "a little coin" is not something a 930 box is.. Were taking 6k-10k-and up... depending on how "all out" you go (lsd, gearing, diff.. exct..)

Hold on a little bit, were all trying to find a trani that will hold more hp, and provide very good gear ratio's..

901 box can hold 250-350hp depending on how you drive it.

Bob, the H gear that was sold was
A: used
B: had at least 10 people try to buy it at 200
c: tends to go for 500+

The solution that I mentioned was an audi box that should hold 400hp no problem, but the gear ratio's are very attractive. Also has LSD avalible for it for a decent price to..

Dont have the links for that, but someone does.

[army dude]

Hey Andyrew,
what kind of set up do you have in your 901?

Ian in Iraq

[rick 918-S]

Contact Brad Mayeur, 914 LTD. Inc. 309.694.1797 He has "H" gears and can complete the install. Pretty easy to ship him your tranaxle.

He has my transaxle and is just completing the install of an "HB" and and moving the other gears around for a more even spacing. New syncro's , etc.

[wbergtho]

Hi Ian,

I have a 930 box attached to a 500HP LS6. I use stock 1973 (early 911) driveshafts...I'm told they are stronger than saya 86 911 driveshaft. Maybe the other guys have more info on this. All I can say is that my 1973 driveshafts are holding up fine with 475 ft lbs of tq. I had some spacers machined up to fill in the gap although I should have just taken an old pair C/V apart and used the C/V hub as a spacer. They are the perfect width.

As far as gearing goes for the 930, you'll be plenty happy w/ the stock ratios. With 25" tires...running 7000 RPM...in a vacuum...you'd be hauling ass @ 197 MPH! So I think you won't have to regear it with taller gears. You'd spend a small fortune regearing one of these boxes. Here's the math... 1987 930 4 speed STD 4th gear ratio = .625 STD final drive ratio = 4.222 Ring & pinion = 9:38 Equation... RPM X tire diameter X 0.002975 divided by gear ratio X final drive = MPH So determining top speed in 4th gear @ 7,000 RPM w/ 25" tires is as follows: 7000RPM X 25" X 0.002975 DIVIDED by .625 X 4.222 = 197.29 MPH. The gear ratios are so great for V-8 use...check this out. The following speeds will be attained @ 7,000 RPM w/ 25" tires. 1st = 56 MPH, 2nd = 97 MPH, 3rd = 141 MPH, 4th = 197 MPH. Of course if your engine only spins to 6,500 RPM everything slows down a bit. You're still going to be very fast. (IMG:http://www.914world.com/bbs2/html/emoticons/aktion035.gif)

Bill

[Dr. Roger]

hey hey ian, (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)

there are 911 axles which require spacers only at the inward CV flanges and not at the swing arms. they are, i believe turbo carrera axles and can be identified by measuring the CV diameter, about 110mm's and the length of the splined and threaded section lengths.

the diameter of the splined section is identical to the stock 914 axles but with a different spline count.

threaded part is identical to 914.

warning: the CV is so large that it literally almost touches the inner swing arm. if it's dirty in there it will just touch. =-)

(IMG:http://www.914world.com/bbs2/uploads/blog-1113198627.jpg)

(IMG:http://www.914world.com/bbs2/uploads/blog-1113198593.jpg)

(IMG:http://www.914world.com/bbs2/uploads/blog-1113198650.jpg)

[Andyrew]

QUOTE (army dude @ Mar 16 2006, 09:58 PM)

Hey Andyrew, what kind of set up do you have in your 901? Ian in Iraq

Stock 901 box, Kennedy VW flywheels with stage 4 clutch/PP package. VERY light flywheel, spins faster than any v8 car I have seen. (good and bad thing)

Engine is a rebuilt 350, with smog heads and everything else done to it.. lol

The heads are my limiting factor.. Swapping them out with some good heads will give me 75-100 more hp..

But if I do that, my 901 will be toast!!

Im at 275rwt (or more, done a 'few' things to the car...) or 315 crank tq.

I drive it pretty easy, and my tires hook up. ran with 255's on the rear for a while.

Will be putting 285's with stickyer tires...


Im known as the CV killer.. have gone through 3... can swap in 30 mins with the tools in my trunk (I always carry a spare)

[Andyrew]

Yall need to resize your pic!!

Ifranview works good (download from their site.. search on google)

I'll do it this time... (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)

Delete your post, and repost the words..
Your paragraphs and big picture make reading your text difficult..


Andrew