Keeping it brief,

My engine (5jj R1) was blowing a bit hard after my 2 day trip to Spa over Easter. Not too much of a surprise as the car has done a lot of track days in the last 2 years,

A compression test with figures from 85psi lowest upto 140psi highest confirmed a problem, a leak down test combined with a lot of blowing from the crankcase breather confirmed a ring/cylinder problem.

With another trip to Spa in June planned i sourced a replacement engine with hardly any miles, 6k was mentioned if I remember correctly.
Installed the engine yesterday and it appears to be in worse condition than the old motor,
Compression is bellow 100psi hot and cold on all pots but does shoot up,when some oil is added, the pressure from the crankcase breather is very strong with a constant puffing of smoke on idle and revs, there is also a constant misfire which I've tracked down to cylinder 1 Which happens to be the lowest cylinder when compression tested.
The car won't idle at anything below 1500rpm and won't start when hot, it needs to be left too cool down.

Problem is, I now don't feel comfortable buying a replacement engine and I'm unsure if paying to have a 5jj rebuilt is worth it from a financial point of view,

Perhaps it's time for a later/fuel injected motor.

What would you guys do?

[Edited on 12/5/13 by gaz_gaz]

Simples -fit a car engine
Seriously though akaKeith on here is probably the guy to talk to about that.
He's had some experience of replacing bike engines and can thus talk with authority.
From your description it sounds as if the current one is knackered.
Bearing in mind any bike engine, even in a Se7en, is being asked to do something it was never designed to do (sits back and waits for the onslaught).
Cost to re-build/re-fresh most bike engines is normally prohibitive but if you want to explore that route talk to Roe Engineering in Fleet.
I think your best bet, especially if you are planning long distances is to go for the latest, lowest mileage one you can afford.
HTH.
Cheers, Pewe10

There was a guy on here with a 1300cc Vulcan(?) Pinto(?) crossflow and related gearbox. From what I remember it had some sort of bling attached to it, which may well make it cheaper if you didn't want that sort of thing.
Probably the way to go, get a nice sensible old reliable car engine in the car.

I'm not interested in a car engine for this particular car,
I have a nice car engine in my 5 series, that's enough for now.

Does anyone have any experience with Jon at JEBS Performance?

Have you called ab performance?

If your first engine has been diagonsed with ring/pison wear, and the 'new' engine looks like it has head problems (no compression change with oil in the bores), is it worth swapping the old head onto the 'new' engine?

If it were me I would rebuild one of them or get a good replacement from a reputable seller. No hassle with new cradle, exhaust or power commander etc. The 5jj is considered to be a very reliable lump so worth sticking with. If /when my 4xv goes pop I will probably upgrade to a later r1 or a zx10r lump but I wouldn't want to be doing it at the start of summer.

As SDH2903 says, I'd also buy a replacement engine. Fit the engine and then rebuild both of your spares in your own time. Sell one of the engines to recoup some money and save the other engine as a spare.

Phil

Try to stick with the same lump. Some good advice above. Speak to Andy Bates at AB Performance if you choose to replace or rebuild.
From an upgrade point of view, i upgraded my BEC from a 919 Blade engine (carb) to a modern '09 1000rr Blade engine (Fuel injected). It wasn't until i got into it, did i realise what a task it was going to be. Here is a brief list!:
New engine cradle (bespoke to fit new engine & engine bay)
New Exhaust system
New fuel system (from low press. to high press for FI) which inc. High press fuel pump, low press fuel pump, swirl pot, fuel tank mods, high pressure fuel reg, lines etc.
upgraded oil system cooling (oil cooler)
Re wire & make up of complete engine loom back to ECU (66 cables), Worst & longest job (and i'm an electrician!)
Clutch & Trottle linkages & cables
Power commander
mapping

etc, etc, etc

Having said all that, now i'm out the other side, it's bloody fast and i'm really glad i spent all the time & money over the winter

Good luck with what you decide to do, and if you need any advice, just ask.