How fast are you going when you are in fifth gear and doing 2000 rpm. Just need and aprox. value here nothing more nothing less. Thanks

i don't have a /4 owner's manuals - owner's manuals have a nifty 'speeds in gears' chart in the back.

however - that chart assumes you're on the original 165R15 tires.

not sure why you'd want to know how fast i'd be going, since you don't know what kind of tires i have, and BTW - you didn't mention yours either. makes a BIG difference.

anyway - although i don't know how fast you're going, i do know -where- you're going; straight to the overhaul bay, sooner or later, because 2000 rpm is too slow for top gear...

all at 2000 rpm, calculated based on 205 60 15 tires:

2nd: 16.7 mph
3rd: 25.0 mph
4th: 34.1 mph
5th: 44.2 mph

You will get good gas mileage indeed at 44.2 mph

Even using the holy grail H gearset flipped as 5th gear, you only get 53.2 mph

He's looking to do an engine swap with a TDI engine that likes to cruise at 2000rpm, as stated in a previous thread. However, despite the fact that a gearing program was pointed out to him in the previous thread, which will tell him what speed in any gear using any gearbox or tire combination, he's proven too lazy to go and grab that and find out for himself, and insists on having someone else do the legwork for him.

not lazy just asking a question. Iam still looking into the options I have with this. I would have to know what gears are in the trans to use charts wouldnt I. this is just a quick simple question and if you dont want to give a quick simple answer thats fine. By looking at the other reply I can tell that the stock trans will not work for this. See how nice and helpfull the other reply was. It did not hurt him and helped me and is that not what we are all here for???

i don't read all the threads. i treat each thread uniquely, and if the thread has a question, it better have all the relevant information in it somewhere.

i do not cross-correlate threads, even the threads that i follow.
i do not remember (with but a very few exceptions) who has what year car and what kind of engine they have in it.

boys and girls, there are too many of you and too many differences in the cars for anyone to keep them all straight. some of the differences are quite significant. take this question, for example:

"can i used a Mallory distributor on my car? it has the original injection..."
well of course you can, IF you have an L-JET car. there is no *THE* original injection.

"where can i get a carburetor rebuild kit?"
[ typical harrangue on the superiority of FI over carburetors... ]
"oh - should i have mentioned it's a /6 ?"

sorry to hijack the thread...

THANK YOU that is what I needed to know for my trans choice. I now Know I need to go with another trany choice.

this question has been asked and answered many times, on this forum and elsewhere...
the information is already out there ...

And by looking at the gears program, you could see what other gear ratios are available for the stock trans to perhaps make it work, and you could see what effect different sized tires would have. But you'll never know that until you go and see what that program will do, now will you?

I generally find answering not only the asked question, but anticipating all of the likely follow-on questions and answering THOSE, saves everyone a lot of time and effort. Posting an answer that allows someone to easily answer a great many potential follow-on questions for themselves is even more helpful. Someone who refuses to play and just wants their specific answer now is annoying, as they'll inevitably ask the follow-on questions, anyway.

To shortcut the whole process: go talk to the V8 guys on the Porschev list, as what you clearly want is a transaxle with a much taller combination than you're likely to get from Porsche parts. The V8 guys also all want tall gearing, and if anyone knows how to get it, they will.

Hey LAPUWALI I already have the info and the others are not bitching about me asking a simple question. So relax Im going with another trans that I know will have the correct gears. Just I need to buy one of those and I have the side shifter that I now will be selling. So let it go. Oh I see you are from Cal. that explaines alot.

Rich, I completely agree. I didn't mean my statement as a slam on you, just pointing out how I knew he was doing a TDI swap, and indicating this was a repeat of another thread that had more information, which this guy was starting a new thread for because he wasn't getting his answer on the prior thread. In other words, he was breaking that rule above.

To the original poster, Rich's advice is a good way to get good information out of a board like this. Asking an overly specific but incomplete question like "how fast am I going in 2000rpm in top gear," you invite answers like Rich's, basically wondering why you're asking. If instead you asked something like this:

"I'd like to swap in a VW TDI engine, but it wants to run at 2000rpm. Can I cruise at a reasonable road speed at 2000rpm with the stock gearing? My speedo's broken, so I can't answer the question easily. If I can't with the stock gearing, are there taller combinations (or other transaxles), I can use to get a reasonable freeway speed at 2000rpm? I'm trying to go for really good mileage, and I don't really care about acceleration performance."

Nice, straightforward, shortcuts a great many potential "why are you asking" questions, and saves a lot of back and forth Q&A. You'd likely still have been directed towards the gearing program, or asked to do a search, as that question HAS been asked many times, mostly by V8 guys. Had you done a search first, you would have seen that, and you could have asked a more tightly focussed question, or gotten the answer without having to ask at all. You might even have gotten an answer from someone else interested in doing a TDI swap that already had more information for you.

I'm curious what trans you have in mind that DOES have the correct gears.


P.S. I'm from California too. I don't surf.

all i know is the 80mph, 5th gear is about 3800 rpm ...

my tires are a bit smaller than stock, 6% off, but the above is already adjusted for that.

that's all i have,
Andy

For fifth gear it would be .022 mph per each rpm.

Cant we change the differential?

I mean... That would change all the gears....

Andrew

if it was that easy, that is what the V8 guys would be doing instead of trying to find the H gear.

only a few ring and pinion options for these gearboxes...none of them too ideal for drasticly reducing the RPMs

I think Renegade was looking at having new ring and pinions made, but the cost was too high to justify it.

:finger2:

You mean the ring & pinion gears, of course. The differential doesn't affect gearing at all...

The main problem is a) different "enough" ring and pinion gears aren't available for the 901, the pinion is part of the mainshaft, so you have to change the main shaft to change the pinion. You'd need to do this, anyway, as a ring gear of substantially different diameter would require you to change the "depth" of the pinion, which would be lengthening or shortening the mainshaft (or machining the case to move the intermediate plate closer, or adding a spacer to move it farther away).

In any case, not a trivial job on this or many other transaxles.

Hey mike, can you MAKE gears?

My dad was askin me this the other day.... I said no because of the angles...

eh?

I could, but I wouldn't trust them any further than I could throw 'em

seriously, very specialized tools (hobbing) are required, then there is the issue with material and heat-treating.....

when it comes to re-gearing the 901 box, I think one just needs to be realistic and use what is available or look at a different transmission....as with project, with enough money, anything can be done, but if you have the money, hopefully you have the brains to realize that there are better transmissions available that will suite your needs

this one's easy - you "just" get a pair of early VW bus gear-reduction hubs, and drive them backwards :-) ...

Larry D,

I guess I lost track of the other thread... but I thought you were building a RACE car.. ?

Is the race car off the table now for a TDI?

b

Woah, never heard of those.. Some sort of planetary gearboxes that go on the output shafts I suppose? My MGB has an overdrive unit on the end of the trans.. I'd pretty much considered something like that as pretty much impossible for a 914 as they aren't light or small, and you'd need two...

Guys, keep it simple. Just run bigger tires. Much, much bigger!

Recalibrate the speedo, get Paul to do the flares.....

I have a couple of irons in the fire. Race car is primary, TDI is a long term on going deal. I will probably end up with a trans form a passat or audi they have gears to close what I need and will bolt up with out an adaptor.