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1970 911E vs 911T engine differences

Posted: Sat Jan 27, 2024 5:33 pm
by RobFrost
The more observant of you may have noticed a 911 2.2E engine in today's Anglia Car Auctions - which I bought today unseen for a future engine build project.

I was also the underbidder on the set of four fuchs deep sixes, so I apologise if I escalated the price for another ddk-er.

With respect to the 2.2E engine, type 911/01 compared with the 911/07 in my 1970 911T, I'm expecting it to have higher compression, wider ports, larger valves? hotter cams, a counterweighted crank, and it has the MFI system instead of the Webers on my T.

Are there any other significant differences between these engines, such as oil system, case reinforcement etc.? I'd like to keep my matching numbers T engine case and upgrade it with elements of the E engine. Are there any reasons why I shouldn't do that, things I should watch out for or advisable ways to proceed?

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Re: 1970 911E vs 911T engine differences

Posted: Sat Jan 27, 2024 6:09 pm
by Nine One One
From tinternet.......

The 2.2T heads are similar to the 2.2E and 2.2S heads (as well as the 2.4T, 2. E and 2.4S heads) in that they have the same valve sizes (46 intake /40 exhaust). However, they have much smaller porting. The T motor has 30mm porting, the E has 32mm, and the S has 36mm.

Then someone says........

When you do an internal parts swap you must look at what Porsche did with your selected components. A 2.2 T has excellent cylinder heads, which are basically the same as E heads of the same year less injector holes. Each has 46 mm intake valves and 40 mm exhaust valves, and each has 32 mm int & ex ports. So the heads are OK. Now, the cams are a direct replacement (a minor modification must be done to the left cam to deal with the MFI pump drive). However, Porsche's "package" for the E engine includes pistons of a higher compression (9.1:1) vs the T pistons (8.6:1). So, the solution here would be to replace the T pistons/cylinders with a set of E units. Now, to maximize what we've done so far, we have to look at the engine's bottom end, and decide if the T crank (non-counterweighted) will be able to cope with the increase in top end performance, or if an E/S (counterweighted) crank should be found. When that decision process is complete we have to move to the fuel delivery system, in this case the 2.2 T uses Zenith 40 TIN carbs. They are great for street 2.2 T use, but virtually no performance parts (venturis, etc.) are available, so they will not be able to maximize our new engine's performance potential. So now we have to switch to Webers, PMOs, or MFI (which would have been decided on before the project began - injector holes would have been machined into the intake ports). So, to maximze the T to E (cam) change involves a lot more than a simple cam transplant. Yes, you might gain a small bit of driveability, but an E engine it will not make.

Now, to install S cams, well, that just would not work. S heads had intake ports opened up 4 mm, and exhaust ports opened 3 mm, over the T and E configuration. Compression was increased to 9.8:1, and all of those changes were done to maximize the radical nature of the S cam, which allows an engine to come to life above 4500 rpm. The fuel system would be incapable of supplying the fuel/air needed, the tiny ports would be unable to flow a satisfactory mixture, the combustion chambers, as a result, would suffer, and all of the mis-matched pieces would fight each other rather than work together.



A ’T' case may not have seen as much heat/stress as more powerful engines but, at the very least, you will need to install case savers for head studs. Many of these old mag cases need the case halves decked (shaved so the halves fit perfectly together again, no gasket) then line bored so you can use STD bearings. Then, you will probably want the oil bypass modification and piston oil squirters. And, if you go to 90mm P/C’s, the spigots will have to be enlarged to 97mm, something I’ve been told is risky for anything but fortified “7R” cases.

Re: 1970 911E vs 911T engine differences

Posted: Sat Jan 27, 2024 6:42 pm
by hot66
Don’t quite understand What you are trying to do

Re: 1970 911E vs 911T engine differences

Posted: Sat Jan 27, 2024 8:02 pm
by RobFrost
hot66 wrote: Sat Jan 27, 2024 6:42 pm Don’t quite understand What you are trying to do
I'm trying to keep the original 911T case and up the power closer to say 180 with good torque
Probably hotter than the 911E. Maybe S spec heads, T crank, DC40 cam grind. 7,200 redline, Keen to up the compression - maybe T pistons, bit abut unsure whether to go twin plug. But I didn't know if there's any issue doing all that with the T case.

Re: 1970 911E vs 911T engine differences

Posted: Sat Jan 27, 2024 8:08 pm
by hot66
If it was me …. I’d build up a hot motor from the e and fit that to the as the e has all the right bits …. I’d keep the matching numbers t motor stock and keep it with the car.

I’m fairly sure the t crank isn’t suitable anyway for 7200 rpm as it’s not counterweighted

Re: 1970 911E vs 911T engine differences

Posted: Sat Jan 27, 2024 11:08 pm
by IanM
As the engine is in the UK, it probably came from a RHD car originally. If it was me, I would spread the word first of the engine number in case there is someone out there looking for their matching numbers engine.

Re: 1970 911E vs 911T engine differences

Posted: Sun Jan 28, 2024 5:33 am
by RobFrost
IanM wrote:As the engine is in the UK, it probably came from a RHD car originally. If it was me, I would spread the word first of the engine number in case there is someone out there looking for their matching numbers engine.
That's a nice thought. I understand many E's either started out as sportomatics or ended up as race cars. Engine number is 6200731.

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Re: 1970 911E vs 911T engine differences

Posted: Sun Jan 28, 2024 5:39 am
by RobFrost
Aside from the differences listed above, i have no clue whether the cases are any different between the three engines.

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Re: 1970 911E vs 911T engine differences

Posted: Sun Jan 28, 2024 7:48 am
by sladey
James suggestion makes sense to me

Re: 1970 911E vs 911T engine differences

Posted: Sun Jan 28, 2024 9:05 am
by IanM
RobFrost wrote: Sun Jan 28, 2024 5:33 amI understand many E's either started out as sportomatics or ended up as race cars. Engine number is 6200731
https://angliacarauctions.co.uk/classic ... ngine 

Engine type number 911/01 = manual
Sportomatic = 911/04

I think most E race cars were model year 72-73 (2.4 cars).

Re: 1970 911E vs 911T engine differences

Posted: Sun Jan 28, 2024 9:29 am
by Lightweight_911
.
Piston squirters were introduced for the 1971 2.2 models but if both the E & T engines are from 1970 the cases will be the same (apart from the engine serial & type numbers).

I don't want to dampen your enthusiasm but I think you've chosen an expensive route to building a 'hotter' engine since it's likely that the E's mfi components will all require rebuilding & the pistons & cylinders are unlikely to be useable - & you say you want to increase the compression ratio anyway.

The valve sizes are the same for each of the 2.2 T/E/S engines - only the port sizes are different (although I seem to remember that the carburettor T engines had the same 32mm port sizes as the E).

.

Re: 1970 911E vs 911T engine differences

Posted: Sun Jan 28, 2024 9:58 am
by RobFrost
Lightweight_911 wrote: Sun Jan 28, 2024 9:29 am .
Piston squirters were introduced for the 1971 2.2 models but if both the E & T engines are from 1970 the cases will be the same (apart from the engine serial & type numbers).
Thanks
Lightweight_911 wrote: Sun Jan 28, 2024 9:29 am it's likely that the E's mfi components will all require rebuilding & the pistons & cylinders are unlikely to be useable - & you say you want to increase the compression ratio anyway.
Why's that, you mean for my stated purposes, or because of condition?
Lightweight_911 wrote: Sun Jan 28, 2024 9:29 am
The valve sizes are the same for each of the 2.2 T/E/S engines - only the port sizes are different (although I seem to remember that the carburettor T engines had the same 32mm port sizes as the E).
I read here https://www.early911sregistry.org/forum ... and-others the T has 30mm ports vs 32mm for the E so maybe the best option is to drop the E engine in while I open up the ports (and other changes) on the original T engine.

Re: 1970 911E vs 911T engine differences

Posted: Sun Jan 28, 2024 11:18 am
by SeanP
I am with Andy here

Having gone through the process of building an E engine that came in boxes. I have the following specification engine

E 84mm cylinders
E pistons
E heads
E 66mm counter balanced crank
Solex grind cams
Weber 40 IDA carbs
123 distributor
CDI box.

This is basically a 2.2E engine with carbs and different cams. The solex grind cams are all most the same as the E cams but give a little better bottom end.
To get your E engine back to spec you would need to send the MFI pump off for refurb and calibration. The throttle bodies would need to be refurbished. An engine rebuild on its own is quite expensive.

You also need
A fuel filter console.
A new fuel pump.
MFI wiring loom.
CDI Box.

An option would be to find a 2.4 crank and con rods and use the 2.2E cylinders and pistons, the E cams, and your Weber Carbs to build a higher compression longer stroke street engine. You could then get a set of 86mm cylinders and pistons and build a 2.5.

Wayne Dempsey book has lots of suggestions on engine configurations.

Regards

Sean

Re: 1970 911E vs 911T engine differences

Posted: Sun Jan 28, 2024 3:24 pm
by 911hillclimber
Dempsey book is aged send for this kind of stuff Rob, and the rebuild process beautifully written and presents.

When I built my first flat six the E 2.4 came in 3 boxes of utterly stripped parts.
I added S pistons and kept the rest.
Pump was done by Diesel Services for little money.

Worst bit was restoring the injection manifolds of corroded magnesium fuel drillings, all done in my garage.
Well within your grasp.

I’d do a hot E, keep the E cams and leave the T engine alone.

Back in 1992 the engine and all services cast less than £1000….

Re: 1970 911E vs 911T engine differences

Posted: Sun Jan 28, 2024 3:46 pm
by RobFrost
911hillclimber wrote: Sun Jan 28, 2024 3:24 pm Back in 1992 the engine and all services cast less than £1000….
Add a zero and then some these days...

This the right book? https://www.ebay.co.uk/itm/354852192503

Not this one I take it https://www.ebay.co.uk/itm/235396666107