tuning from 911t/e into 911e

[matrix]

Hi,

Iám the owner of a 911t/e 1972. The car is original sold in the us and then shipped to europe. European 911e's have 165 HP instead of the 140 HP I have. My question is; what's the most easy way to increase the performance of my T/E and is is possible to convert the engine to a "real"E?
Thanks, Hans Scholten-netherlands

[YTNUKLR]

Well, the differences between the two are:

-Camshafts
-Pistons
-Cylinders
-Head ports (32/32mm vs. 29/29mm)
-MFI throttle body size
-MFI stack size

Making it a real 2.4E engine, you need to buy a set of 2.4E pistons and cylinders, a set of 911E MFI camshafts, port out your cylinder heads to 32/32 and rebuild your MFI or buy 2.4E MFI. You could also buy 2.4E heads instead of porting your T heads. Pistons can be increased in compression as well, and would work great on a 2.4E (say 9.5:1). Camshaft switch to 911E or Solex would be awesome. I assume you do want to stay with the E "feel" and not the S?

Best
Scott

[Grady Clay]

Hans,

I think you have a USA version 911 T-E “einspritzung (MFI)” 140 HP as opposed to a European carbureted 911 TV-E “vergasser” 130 HP. I think both have pretty much the same specs – 7.5:1 CR ugh.
The “E” in this nomenclature refers to the body – ’72-’73 and no flares.

Scott is right on the mark. It is exceedingly expensive and complicated to change from “T” to “E” to “S”. There is a lot different to a ’72-73 911 E-E (165 HP) or 911 S-E (190 HP). There is also the ’73 2.7 911 SC-F (210 HP) aka the Carrera RS.

Best,
Grady

[Bobboloo]

Hans,

What is the car to be used for? Street, track or both?

The reason I ask is because this should guide you on decisions with the motor.

For example, If the intended use is for the street then I would stay with the T motor. The only thing I would change would be to raise the compression from 7.5:1 up to 9.5:1. This would give you additional torque with a cam that is well suited for the street.

If the car is to be used for the track as well as the street then I would go with E cams and ports along with the compression increase.

If for track only then I'd go for an S motor.

Even though the 2.4S can boast 190HP, if you drove a 2.4S and then a 2.4T in city traffic you would swear that the T was more powerful because in fact it actually is more powerful in the lower RPM range. It has more torque up to 4000 RPM but from that point on the S is more powerful up to 7300 RPM. The T is also more powerful than the E up to 3500 RPM.

[YTNUKLR]

Torque is what's important! Take a look, Bobby is right on (as always)

[YTNUKLR]

I erased the 2.7 engines for simplicity. You can see they are all up way higher than the 2.4.

[matrix]

Thanks for all the reactions.
The car is used for the street. If I understand it well the best thing to do is replacing "E cams and ports", any idea about costs ?The alternative which my local Porsche Specialist is offering is to switch to an 3.2 engine ( a rebuild block, including hours cost about $ 8.000.- if I keep the existing 2.4 engine) which is a lot of money

[Tim Walsh]

for about $5-6k US and doing the work yourself you can make an E motor. Here's another option. Find a core 2.2E or S motor that you can take the heads, cams and pistons out of. Then have your throttle bodies bored out to 32mm (to match the 32mm ports) and the last peice would be to find some 2.4E stacks.

This is basicly the route I went, except I found a steal of a deal on brand new JE's so I sold the E pistons and used the new JE's instead.

[Bobboloo]

The car is used for the street. If I understand it well the best thing to do is replacing "E cams and ports",

I think you misunderstood me. Maybe not.

My suggestion was to leave the ports and cams the way they are for a street motor. Just switch the pistons to higher compression for more punch.

The cost of a set of 9.5:1 pistons from JE for example would be $1000 US.

Is the motor in need of a rebuild or do you just want more power?

[Jim Richards]

Originally posted by Tim Walsh
and the last peice would be to find some 2.4E stacks.

Or have your plastic stacks bored as well. Mine are back from Eurometrix and they look great. Sorry, no pics right now since my wife's out of town with the dig camera.

Bobby's suggestion about a high CR T engine sounds like the economical way to having a fun engine.

[camgrinder]

For good torque and a hp peak +/- 5000 rpms, just bump the compression and use the E cams.
If you start porting the heads and milling out injectors etc etc, you might look at that 3.2 litre swap.

[Jim Richards]

John, I'm curious, does the use of E cams require anything to be done with the heads? Is there enough piston-to-valve clearance?

[camgrinder]

Jim,
No probelms with valve springs etc on the heads.
I have never heard of anyone with a valve to piston issue going
from a carb T cam to an E cam.
You would have a problem using the E cams in a 2.4 cis or 2.7 cis engine.

[matrix]

[
My suggestion was to leave the ports and cams the way they are for a street motor. Just switch the pistons to higher compression for more punch.

The cost of a set of 9.5:1 pistons from JE for example would be $1000 US.

Is the motor in need of a rebuild or do you just want more power? [/B][/QUOTE]

It's just more power, and if I understand it well everybody agrees with you're idea. Any idea what it brings in terms of more HP ?

[jluetjen]

Any idea what it brings in terms of more HP ?

As a rough rule of thumb, the increase in HP from a CR increase will be a little less then proportional increase in CR So if bump the CR from 7.5:1 to 8.5:1 (roughly a 13% increase), I'd expect the HP to increase by something less then that, say maybe 10%. (Keep in mind that this is "rule of thumb", back of the envelope type of thing.)

The big improvement will be in the that there will be pretty much an across-the-board increase in torque which you should be able to feel when pulling away from stop lights, etc.

The risk is to keep an eye on detonation. Admittedly the CR's that I listed are well below the 9.5:1 limit for a single plug engine on street gas, but you can't forget that you are running T cams which are fairly mild and so you may find your static compression going up more then you expected. E's and S's with their later intake valve closure tend to have a lower static CR then their listed CR would suggest. To put it simply, you might need to change from regular unleaded to super unleaded.

[Jay Auskin]

I also started with a stock 2.4 T motor. I increased the compression by installing 2.2L T pistons. I came across a good deal on them, so it was a very easy decision for me. It's a nice, torquey engine for street use. I'm guessing my CR is around 9.5:1 (stock 2.2L T was 8.5:1?). I've had no trouble using 91-93 octane "pump gas".