Waynes' Top Engine Choices

[JPM]

Wayne's DIY documentation on 911's has been a great help along with postings on Pelican bulletin boards. I am assembling a 2.4S to put into my '69 911T. If there is one thing missing, it is a discussion on adapting the engine upgrades to the transmission.
My 901 trans has the push-type clutch, using a 215mm clutch, with the one piece flywheel. Apparently I am stuck using it with the new engine. The 2.4 engine came with the later 2 piece flywheel but I am unable to find a way to use it along with the later '72 clutch and pressure plate.
Since engine retrofitting has been going on for a while, I wonder what options are out there?

[Trackrash]

Lots of options, but, either a 69 flywheel or a 915 transmission, clutch and shifter would work.

[unclebilly]

It can be done. We ran a 901 and a 911 trans in front of a 2.7 in the chump car. You need the early clutch setup and get a performance pressure plate or it will slip. Also don't get too excited in 1st gear or it won't last more than a day.

[JPM]

either a 69 flywheel or a 915 transmission, clutch and shifter would work.

Trackrash granted but I am trying to avoid going to a new trans.

You need the early clutch setup and get a performance pressure plate or it will slip.

Unclebilly, you mean like going to a Kennedy clutch.

[Wayne 962]

The 911 transmission was basically a 901 transmission with the clutch mechanism flipped around and a different bell housing. The 911 and 901 internals are very similar. 1970-1971 was the years for the 911 transmission. In 1972, they went to the 915, which was better except for the initial 1972 year, because one of the seals was mounted on the inside and is impossible to replace without tearing down the entire transmission (they fixed this error in 1973).

The 914 rally car I have was built with a 911 transmission and converted into a four-speed. As unclebilly mentioned, first is weak with strong engines, and you may break it if you're not careful. The four-speed option with tall gearing seems to work very well in the 914. You can upgrade the whole setup to a 911 transmission if you'd like to get the better / improved clutch setup over the 901.

However, re-reading your original question, I'm not sure exactly what the question or goal is?

thx

[dwelle]

how is that 911 working as a 4 speed, wayne? i have a 914 with a 3.6 running 275's (!) in the back. the 911 has been rebuild prior to my purchase. eric shea at PMB helped me broker the deal, and he turned me on to the notion of converting it to a 4 speed so i don't break 1st. i'd like an LSD in this car, so i'm contemplating it.

any thoughts?...

[JPM]

Originally Posted by Wayne at Pelican Parts

You can upgrade the whole setup to a 911 transmission if you'd like to get the better / improved clutch setup over the 901.

Like everything, it's a cost/benefit question. I wanted to use the later flywheel with my 901 trans and thought that a '72 clutch/pressure plate would work . Upgrading to a 911 trans does not seem a simple matter with all the hardware changes. Since it is intended as a street car, I will use my old flywheel and investigate if a higher pressure clutch makes sense. Sorry for not stating the goal more clearly.

JP

[Trackrash]

Originally Posted by JPM

Like everything, it's a cost/benefit question. I wanted to use the later flywheel with my 901 trans and thought that a '72 clutch/pressure plate would work . Upgrading to a 911 trans does not seem a simple matter with all the hardware changes. Since it is intended as a street car, I will use my old flywheel and investigate if a higher pressure clutch makes sense. Sorry for not stating the goal more clearly.

JP

I wonder if someone makes a clutch that would work with the 901 trans and a later flat flywheel? Kennedy?

Then again, if you had a really grabby clutch wouldn't it just add to the problem with the weak first gear in the 901?

At any rate, you wouldn't want to mess with the 911 '70/'71 clutch setup. It would be a hassle to set it up. The '70/'71 clutch release arm pivot is truly mickey mouse and it is definitely not an upgrade. AHIK.

[JPM]

Originally Posted by Trackrash

Then again, if you had a really grabby clutch wouldn't it just add to the problem with the weak first gear in the 901?

Okay, so the crux of the problem is the weakness of 1st gear whether using a 901 or 911 trans . The solution alluded to by Wayne in his 914 is to convert to a 4 speed with tall ratios. Kennedy told me some people get rid of first and change the ratios of 4th and 5th to make it a 4 speed, but that is for adapting a V8 with a lot more torque.

So I'm kind of stuck between keeping it stock and having 1st gear slipping or using a Kennedy pressure plate and risk breaking first. I'm inclined to try the Kennedy solution