Gonna do it. Lotus Esprit SBF.

Doug S.

The protoplasm may be 72, but the spirit is 32!
Lifetime Supporter
I'd like to end up with a complete engine (including induction/ignition) for under $10K. Any suggestions?

Seems to me you might be able to get a stroked 302 alloy block with alloy heads, intake and water pump built by somebody like Keith Craft for around that. Since weight seems to be an issue I think an alloy block would be a high priority for me if I were building this cool project you've got going. I know one of my favorite builders from the Club Cobra forum doesn't like the 331...he says, as do we all, that there's no replacement for displacement and so he sells far more 347 8.2" Windsors than anything else...but for me, I like the sound of a high-winding small block, perhaps with solid lifters (I don't mind fiddling with the valve-lash now and then), so I might go with a 289 or 302...IMHO the smaller the crank throw the higher the engine can be safely rev'ed.

This has been a fun thread, Cliff....wishing you the best of luck with the build!

Cheers!

Doug
 

Ron Earp

Admin
Now where to get a reasonable 331 stroker?

Start with your local machine shop. You should be able to assemble a nice 331" motor for under $8k. My local shop we use for our race work would certainly be happy to quote one out for you and ship it to WA.
 
Thank you fellas. I really appreciate the advice and insights, very helpful. I'm making some (very slow) progress.

Quick update. I have my audi 016...new seals, diff bearings, etc...and updated with an 80% LSD from a 944 turbo. This is what I have been working on for the last couple of months....mostly because it's easy and familiar territory for me. I haven't yet found a strengthening plate kit for the backside of the gearset but one will pop up somewhere (or I'll make one). I have a lead on an kennedy adapter plate, along with some shift linkage that should work well.

I've been chewing over engine options. From a practical standpoint of just getting this project moving forward I think it may be best to just get a basic 302 SBF and bolt it up and get it installed and functioning. I would anticipate the engine coming out down the road for an upgrade to a stroker with all the nice go-fast bits, along with an induction upgrade (I'll start with a basic Holley then go to EFI).

I'll do some mock up with a foam/plastic 302 block to get the engine mounts properly engineered and placed - I can MIG and TIG weld pretty well. But overall, I think the basic dimensions are very good. The 016 is a bit more compact than the Citroen transaxle, with the output shafts closer to the bell housing face. The rear mounting points are in about the same spot. All good. My Esprit is an '88 with the inboard brakes so I'll have to get some later (89+) rear uprights with the ears for brake calipers. I should have started with an '89 but ah well, too late now. The existing 2.2L engine is a very good engine with no oil leaks and great oil pressure etc so somebody will want it for a Lotus project no doubt.

The SBF with accessories isn't any longer fore/aft than the Lotus 2.2 with accessories. As far as width, it should be fine as once the air box (on the starboard side of the engine bay) and the turbo piping (on the port side) is out of there it looks like there's lots of room. I'll have to relocate the coolant header tank, probably to the area where the turbo previously resided. I have no idea about exhaust system routing but I can start with mustang headers and custom build downstream from there. Clearance above will be tight, probably have to make some "adjustments" to the rear hinged deck ie. cutting to clear an air filter. I can make it look pretty and stock-ish. On the bottom side of things, the Lotus 2.2 has the bulk of the oil pan capacity located towards the back of the engine. Most SBF pans I've seen have the bulk of the capacity located towards the front of the engine. I might have to revise the pick up location, and perhaps swap a SBF pan fore/aft. Don't know.

There will be a bunch of detail work with regard to making all the gauges work, heating/AC system, shift linkage, etc. but I'll just take it one step at a time. My son is 8 so maybe we can work on it together and I'll have it done by the time he's getting his drivers license...

Now for removal of the 2.2L and Citroen transaxle....
 

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Hi fellas, a bit more info and update here....

It's slow, but I'm making progress. Four kids and a busy job don't leave a lot of time for garage fun, but in any case things are moving forward.

Lotus engine is out. Really a nicely designed engine with good power considering the anemic displacement (2.2L)....about 240 hp and 210 tq. But it's no skinny minnie.....with all the iron around the turbo I really think it weighs just about the same as the SBF with headers. Maybe 50lbs less, but that's it. I'll sell it and the transaxle.

The 347 is just about ready for some trial fitting with the 016. The overall dimensions (SBF and 016 together) are amazingly similar - within one inch in all directions....one inch longer, one inch narrower, one inch taller. The engine mount and transaxle mount positions are also very close. Much simpler engine, and a lot more power - 420hp and 415tq.

I'll post some more pics and info as the install progresses.
 

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Keith

Moderator
Interesting size comparison Cliff. One of the best conversions I ever came across in he UK was a MKII Jaguar Saloon with a 302 in it. To be honest, when you opened the bonnet the 302 looked minuscule compared with the Jag 6 pot. It went like a scalded cat and was quieter and more fuel efficient than the Jag too and it just looked like it belonged in there. One of the many reasons I've always been a fan of the SBF.

Good to see you're getting somewhere at last. The Lotus motor should fetch you a decent price shouldn't it?
 
Interesting size comparison Cliff. One of the best conversions I ever came across in he UK was a MKII Jaguar Saloon with a 302 in it. To be honest, when you opened the bonnet the 302 looked minuscule compared with the Jag 6 pot. It went like a scalded cat and was quieter and more fuel efficient than the Jag too and it just looked like it belonged in there. One of the many reasons I've always been a fan of the SBF.

Good to see you're getting somewhere at last. The Lotus motor should fetch you a decent price shouldn't it?

Thanks, appreciate the encouragement. Definitely some engineering involved with this engine swap but surprisingly similar dimensions. I'm hoping the SBF will look as good in there as in the Jag. Pretty sure she'll scoot along better.

Yup, someone will no doubt buy the Lotus engine - it's in great shape. The transaxle works and shift fine but it really should be gone through by trained folks. It wasn't a good transaxle for the application in the first place, coming from a Citroen van of the 60's. If you know of anyone who needs a good engine.....
 

Randy V

Moderator-Admin
Staff member
Admin
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I think I would pickle the engine, wrap well along with the transaxle and stash it somewhere dry... If you sell it off, you will lose money in the long run because you've cut all ties with what it was born as - which will destroy any value as a future collectible car...
 
I'm sure you're right Randy. But these Esprits are not like a Ferrari or GT500 where originality is everything. This Esprit will never have Lotus power again. The Citroen transaxle was crap from Day 1 too.

Besides, once I get this project finished this wil be a keeper, so re-sale isn't a big thing. It's just a weird bastardized Lotus that'll never be worth much.
 
Im loving your work Cliff. Keep going, Im actually looking at doing something similar except I still need to find an Esprite. Keep the info and pics coming.
 
OK fellas, progress has been painfully slow here due to family and career obligations, but I'm making some gradual movement forward.

Test fitting the engine the other day and all looks good. There's lots of room all around and the front and rear engine mount positions look good. The transaxle output shafts are nicely aligned fore/aft with the hubs so the axles will be very close to 90 degrees off the centerline with appropriate up/down range of motion. The SBF/audi is about an inch longer than the Lotus/citroen but it's not a problem. There's tons of room around the sides and back for the exhaust manifolds and running the left/right pipes towards the back for mufflers. Frankly, I think the SBF is smaller than the lotus engine with all the plumbing for turbo and various engine management devices.

She will go down a couple more inches in the front with a bit of fitting so I think everything will fit under the stock engine cover. I'll trial fit again in the next few weeks and fab up some forward engine mounts.

Once the engine is properly situated it's pretty simple: fuel line, a few temp/pressure sensors, power to the distributor, rpm signal to the tacho, alternator hookup, heater hose hookup, few miscellaneous things, tidy up the lotus wiring, etc.

Hoping to have a good runner here by summer. Once the drivetrain is done I'll refresh the interior and look at possibly a paint job. Fair bit of work, just taking it one step at a time......
 

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few more pics....
 

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Randy V

Moderator-Admin
Staff member
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Nice work there Cliff!
That sure is a BIG distributor to be in a mid engine application. Have you thought about how you were going to service / time it?
 
Randy, yup, that sure is.....you're right. It's just basic, contains the coil, all-in-one sort of thing. When I get things running then I'll upgrade to full electronic ignition with coil packs, and 8-port injection of some sort. For the time being I'll make do with the clunky dizzy and Holley. This project will have some evolution to it as it rolls along.

Thanks for the words of encouragement. I'll keep pushing forward.
 
Hi fellas, making some (very) slow but steady progress here.

I have the engine and transaxle mounts now fabricated in order to position the engine/transaxle correctly using the original mounting points on the tube frame. Looking pretty good. In comparing the weight of the Lotus engine and Citroen transxle...including the heavy turbo plumbing and exhaust manifold, I think the SBF/audi is maybe 50lbs heavier at most. However, there will be a whole lot more torque/hp so I'll add some appropriate bracing once the drivetrain is finally situated and can see what makes sense.

I'm now looking into adding a LOT of extra cooling. For the oil cooling, I have a very nice large-capacity Modine oil cooler (used in NASCAR) with Spal fan and thermoswitch that I'm plumbing in. For the water cooling I'm a little stumped. I already have the upgraded/large capacity Lotus rad up front, but I would like to add some supplemental water cooling. There's nowhere I can put a full-sized radiator, so, I'm wondering if one or two smaller rads with fan would work. Trouble is the smaller sized supplemental rads (such as from an audi A8) tend to have small inlets/outlets and I don't want to decrease flow rates. Do I split the flow in a Y with two smaller rads (one left and one right) or ??

Any ideas much appreciated. Thanks.

ps. I heard the Veyron has 11 radiators....so I'm guessing the use of multiple in-series/parallel rads is copacetic up to some point.
 
Weld bigger inlets and outlets on if possible but the core may be your limiting factor for what it will flow you could "y" it and put in a auxiliary eletric pump to push it through the small radiators when needed or when triggered by a temp sender?
 
Right, that makes sense.....either the core or the inlets/outlets may restrict flow. I'm thinking two smaller radiators in parallel might alleviate the potential restriction???

Quick pic of one of the mounts. Will need some clean up and powder coat, but functional. Mig welding skills a little rusty.
 

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Ian Anderson

Lifetime Supporter
Cliff
How big is the radiator?

How much space is there up front and could you add extra cores thicker radiator to assist?
Also
I know for a fact that in my GT40 adding fans in the engine bay to remove heat assists hugely with the cooling.

Ian
 
The water radiator(s) I'm looking at adding are actually twin audi auxilliary coolers. They're small....which is needed given the space limitations, but between two of 'em perhaps it will add a meaningful amount of cooling. I certainly don't want to impede or diminish flow however. Still working on it.

Related, I have a good sized Modine oil cooler from a Nascar car (cleaned) that I will plumb in with a fan in the rear near-ish to the transaxle.

Progress is slow here. I got the CV axles sorted out - porsche 911 axles were the right length and with 930 CV's should be reasonably strong. Now I know more about CV's than I thought I ever would.....

A few pics here. Again, progress is slow with four kids and a busy job.

Kinda like an english pantera.
 

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