D14A3/A4 versus D14A8

[Dodo Bizar]

Here it is!

In red the D14A4, in blue the D14A8. Except the engine block and cylinder head everything is the same. Both setups had physically the same inlet, inlet manifold, exhaust manifold, midpipe en muffler.

[saxophonias]

So almost identical curves only weaker engine.

[Dodo Bizar]

I think much of the similarities come from having the same intake pulsation timing and exhaust pulsation timing since those were kept identical. I think the cam is pretty different since torque is way lower on most points except for lowest rpm part. And somehow it seems the A8 cams are tuned to produce a bit peaky power at higher rpms for whatever reason. To me you need a completely different cam design to acquire this diff...

[mynameisowen]

I agree, I reckon its in the cams. Its interesting how they are identical in performance between 3-3500 rpm. Must be designed that way so that the engine is still response during acceleration at low speeds.

The EJ9 seems to have ~7% more torque and power accross the range (except for 3-3500rpm). Why do we reckon Honda decided to do this? Fuel consumption? Reduce stress on the engine due to pulling a heavier car (questionable)? Pretty dissapointing for MB guys, if anyone has an MB civic, swap a EJ9 cam in a see if it makes any difference!!

[Dodo Bizar]

That would be a nice thing to try. Would also limit the questionable state of the D14A8 which might arguable have been worn out or something.

[hondaNickx]

Milage and use on both engines would explane those minor differences.
Valves or pistons that have burned particles on them could cause differences in head flow or combustion efficiency.Different cam could also be possible.

[hondamake]

Hi Guys. I've finally got my hands on a D14A4! Picked it up today complete with S40 manual box, starter, alternator etc. - eBay £100 for the lot . Couple of questions, if I leave the D14 camshaft in place and fit my existing D16Y7 distributor will the ignition timing be correct (obviously it will need strobing). I'm going to retain my automatic gearbox for the time being and install the manual at a later date when I have more time. Is the S40 box any good or should I look for something else?

[Dodo Bizar]

As far as I know it's only strobing.

S40 gearbox is one of the toughest. Only drawback may be a bit long final gear, making the 5th gear a bit long.

[hondamake]

Latest news on engine swap/upgrade. Because of work commitments and the cold weather, in the gas biz the two go hand in hand, I've had to take a shortcut. I've fitted the D14A4 head to my existing D16Y7 block and auto tranny. The D14 head has the casting mark P2A-5 but appears identical to the D16 head which is marked P2A-2. The performance appears the same. More importantly I now have a D14 block plus a D16 head plus a manual S40 gearbox to build my project. I also have the offer of an IM from a Concerto/Rover 216, anybody tried using one? I could do with some knowhow on ECU's so I'll post my questions in the right section.

[Dodo Bizar]

Can you provide us with a picture of that IM?