Planning my Europa's future

[E Paul]

4525 is still in really fantastic condition. The 25 year old respray still looks near new. Interior, not perfect in any way, but still nice. No rust. More brakes and suspension bits than I care to count, but no worn out parts there. The motor was reringed about 70,000 miles ago when the head got stainless valves, silicon bronze valve guides, valve seals and stellite seats. The head was truly shot at 30,000 miles. Anyway, had the head off a few thousand miles ago to change a water pump...why I did not put in a Bean pump at that time I dont know, so dont ask. I noticed the the block was developing a bit of a cylinder ridge and thought to myself, not today but not never will I need to redo the block. So right now, I am retuning the Megasquirt that feeds this thing as I did something stupid last year when reflashing the ECU and I got to thinking what is next for this motor. What is the maximum overbore permitted on the cylinders? On a slightly different, but related note, does anyone know if the Pels kit for the Toyota 4AGE can be found or if drawings exist? I love the Silvertop in my Seven. Zetec?
My inclination is to stick with the twink as it would probably bring the best price if I ever sold this thing, but on the other hand I have had it for 46 years so probably its going to end up being my kids problem. I would not mind a more modern engine. What you guys do as you or your kin might be ones to grab this if we ever decide to sell.
Boy...this sure reads like a ramble...anyway, stop web surfing and back to work.

[BDA]

I think you need to decide what is more important to you. If you're after resale, then rebuilding the twink motor is the way to go. If you want a motor that would be more reliable for a longer time, I would choose the Zetec swap as it's somewhat easier to install. The 4AGE is a great motor but it requires more work to install it. Both will require some fabrication to install and custom headers. The choice of fuel system will obviously impact the bottom line as well as the installation. Any engine swap is likely to significantly limit the resale value.

[RoddyMac]

Is it a Weber headed TC?  If so, I would keep the TC in the car.  Don't quote me on this, but I think most of the late TC blocks can go to 040.  If it needs to go bigger, try to find a 711 bottom end to increase displacement. 

But, if money's the sticking point, and you have no desire to sell it, go Zetec.  2L, 16 valve, bolts up to the stock bellhousing.  The downside is there's no "kit" to bolt it in.  You'll have to dust off your Locost building skills and fabricate engine mounts, alternator mount (if you dont want to buy a kit from Retroford or Burtons), plumbing for the cooling system etc.

[kiwiokie]

I would imagine a 2L Zetec would require an upgrade in stopping power too :-)

[LotusJoe]

The silver top Zetec will bolt to the gear box without issue. I made engine mounts that bolt directly to the stock rubber mounts so as to avoid any modification to the frame. I also made a jig for those mounts so they can be duplicated.  I did put a small notch on the passenger side of the "V" to accommodate the alternator. Obviously there are other modifications needed. But compared to the Toyota swap it is much more straight forward.

[E Paul]

I wish it were a Weber head. That would be the kicker. It is a Z-S head. I hated those carbs and got rid of them back in 1981 when I fitted the engine with a CIS injection system. Since then, it has been converted to Megasquirt. I always kept the mods simple so that it would be easy to put back to original if desired. I think I may be leaning toward the Zetec. The mods needed are well within my fabrication skills.   What fitments of the Zetec are easiest/most desireable? Good crate motors available?
Now we just have to wait for the twink to decide its had enough...it still runs pretty good except for some weirdness at the moment.
On another note, I think I figured out last night why the Europa engine is acting weird. I run a cam sensor for engine timing to feed the ECU. I put a timing light on it with fixed timing and the mark was jumping all around...about 10° worth. I must have a loose timing chain...cant really think of anything else it could be. Tooth log looks perfect.

[BDA]

When I posted to you last night I did a quick search for crate motors. On this side of the pond, Summit Racing sells them without carburation. Dunnells in England specializes in Zetecs sells them as I think I remember so does Burton Power. Used motors show up on eBay occasionally too.

A buddy of mine is building e Zetec Europa and had Dunnell make his header. They are beautiful. If you're interested, I think I can find some pictures he sent me.

[jbcollier]

Cheaper to source a Weber head than to fit a Zetec.

[literarymadness]

On the front face of your block should be a letter stamping: either LB, LA, or LAA. That would give you a better idea on how much you can overbore your engine.  According to the Miles Wilkins book, the LB (the most common) is not suitable for over-boring to 83.5 mm or more.
The LA block can easily handle up to 85 mm. The LAA block is extremely rare and was essentially for Lotus race variants only. Here is a photo of my TC block as a reference.
 

[E Paul]

That is good to know. Thanks, Paul

[literarymadness]

Some more references: An LB stamped Lotus/Ford block and another LA block from a Lotus Cortina.  Most of the LA Twin Cam blocks were sent to Cosworth, Hart, and Vegantune. But the unused ones went to the Europa TC and TCS production line.