Porsche 912E 2.4 stock EFI ?

[angello]

Hi guys , regards from Europe ,
I am a newbie here , member of Samba and 912bbs. Great lover of AC VW s and Porsches. Have recently completely restored a 1974 Super beetle convertible. I have made an 1776 engine with dual 40 dellortos. Its a great fun to drive it

My new old baby is a Porsche 912E and I like her very much but I must admit my beetle pulls a bit stronger. I reckon with 20 HP more they ll be even.
The stock type 4 2.0 engine runs great , rebuilt (aprox 14 k mls ) , stock L-jetronic EFi rebuilt as well ( all hoses , some sensors , AFM ..) runs perfectly.
So I plan to buy a 2.4 liter kit ( 103 mm pistons and cyl.) and nothing else. I reckon CR will rise as well to about 9.2 :1.
I would leave the stock EFI.
I dont like the idea to dismantle the block just to put some new cam. I believe I should change the main bearings every time the block is opened.

Is it possible to leave the stock EFI and will I get some more power just with it?
Thanks for your opinions

[angello]

Ufffff , I forgot I need to bore the block for the 103 jugs. What about 96 mm ?

[Piledriver]

Welcome to the STF, Angelo.

I believe you will find all your engine-related answers on the type4um.
http://www.shoptalkforums.com/viewforum.php?f=1

The 912e is a touch heavier than the SB, but it should not be down on power if running right.
I walked away from several T1s with supposedly well tuned 1835cc setups with a stock 1.7 (with CIS conversion) in my 914.

The stock EFI responds well to proper tuning, but I'm afraid it isn't going to deal well with a much wilder than stock cam or large displacement increase.
A really decent exhaust (A1/Tangerine etc) combined with a good D-Jet tuning job may find you the power you seek.

Even the stock engine leaves a lot on the table, a bit more compression and a cam (flattops) skip the head gaskets (per VW)
perhaps an aftermarket programmable EFI/ignition setup and a better exhaust.
(the factory EFI manifolds and TB are excellent capable of far more than the factory computer can deal with)

Did you build it yourself?
Do you have the european spec flattops in it already? Know the CR/deck spacing etc?

Some engine builders will happily use common//cheap 12-15cc dish bus pistons in a 2L 914 motor, which provides about a 6:1 CR and horrible performance with the 65cc Porsche heads.

The "best" setup varies by user and application, but the 96x78 2270cc T4 combination with good heads and exhaust has proven itself many times.

For just a little more kick, 96mm (2056cc) and a cam.


If there is nothing wrong with the bearings do not replace, the new ones may be much, much worse and not fit the case well.
This is to the point of having the old bearings coated to save them.

You should use the available double thrust cam bearings, this factory single sided thrust is frequently the first thing to wear out and cause "funny" sounds in a well cared for T4 engine.

[angello]

Thanks for your answer , I am moving my question to type 4rum.
I dont really know about the pistons , flat top or not , will find out when they re out.
I have heard there are no more original main bearings unfortunately ?...just China in Mahle box.