Big Bang Theory: Oettinger 2500E rebuild

[silverbullet]

I have recieved a quote to weld, straighten, re-machine, grind and balance 2.1 cranks to increase the stroke to 82mm.
98mm piston sets pending, need to make a call about the liners in the new year.
All will be UK made/sourced

[Syncrobaz]

How's the camshaft ? I believe they ditched the hyd. lifters in favour of manuals, I wonder if this helps ??

( I haven't located one for my spare engine yet )!!

[silverbullet]

Nope its hydraulic and not in bad nick for 200kkm, but it was in a Carat auto so probably always got proper servicing!

[silverbullet]

But a recent read of whats in more recent EJ engines makes me think that going mechanical and even roller rocker would be a good thing.

[Syncrobaz]

Interesting, anything that prolongs the camshaft's life would be good.

[silverbullet]

Price now in from the USA for full counterweight cranks

[toomanytoys]

Might as well go for some proper rods too then...

[silverbullet]

Haven't shown a pic of the Oetti mods to the std ones yet

From what I have learned from my semi-pro engine builder contacts, wbx rods should be adequate for at least 50bhp/cyl in a n/a engine.

[silverbullet]

I had a peek inside the AFM because I could see that the cover had been resealed, suggesting some old-school period tuning (the test of the DJ efi system is box standard afaics)
[img]http://i1103.photobucket.com/albums/g475/IanHolman/Oettinger%202500E/20150106_174500_zpsluxxkzyv.jpg[/img]
Note the scratch in the toothed spring carrier wheel, 3 clicks c/w from the retaining wire at about 7 o'clock

[Aidan]

I have a similarly modded afm from South Africa, originally fitted to the 2.1 from the Kyalami tuners, big bore exhaust, modded afm, resistor bridge on temp 2, ratio rockers and a mild inlet polish, supposedly made 135bhp, didn't feel like that much but went well, engine was rebuilt and is in the Hulleys bus now
if you measure the resistance on the afm across the range it peaks higher and drops less towards full fuel compared to standard but it's a subtle difference, I guess they needed to do the temp 2 resistance mod to move the map up the graph earlier, it always thinks it is hotter than it is so along with the higher peaking afm reading it delivers more fuel
interestingly they also fitted the k and n recleanable filter which seems to make no difference at all normally and is no cheaper than the Mann paper one over it's lifetime

[silverbullet]

I dont think that the temp 2 has been bridged but I will look at the loom again. Not sure if the ecu has "that" one with the plug-in chip. Its a T&A one iirc

I have heard of this spring mod before, most dramatic was on a supercharged 4.2 Rangie V8 that would only idle at 4000rpm because the engine was pulling in so much more air!

[silverbullet]

Forgot to say that the thermostat had the capsule prised out, so the system had reduced back pressure and must have taken ages to warm up...not good.

[Aidan]

resistor was simply soldered across the two wires going into the junior timing plug and taped over, iirc 1.47kohm somewhere I still have it , in a safe place

[silverbullet]

This avo I finally got around to popping the Oetti case open, mostly to see where the tight clearances occur, before it gets new bearings and reassembled...

I suppose this rather invalidates the argument about the OEM rod bolts being weak...

Very very tight behind the cam thrust face...

[AdrianC]

Not a lot of debate about whether they could have taken that any further, is there?