Lotus Elan and Lotus Elan Plus 2 Forums

Yes pictures please and info on turbo, bhp world interesting too. Thanks.

I wrote an article on the engine design in the Lotus Remarque several years ago. With pictures. I have not posted a picture of the engine installed in the car yet. I designed the engine for 250 hp and 250 foot pounds, at the rear wheels. I should get that before 19 pounds of boost. I have not yet taken the engine up to that level, yet.

I would be interested to know your head gasket design and head bolting arrangements. I have seen the rear of the head lifting and spitting out coolant with a 200 hp normally aspirated engine at 8000+ rpm so ideas on how to hold the head seal on the block in extreme conditions would be useful.

cheers
Rohan

The BDG in street tune for my Elan dynoed out at 225 hp on FI and weighs 40 lbs less than the stocker. Mated to the T5 tranny this should be great fun. Retired last year so hoping to have it on the road again this summer. Doing the dash wiring (20 fuses and 11 relays) as I'm typing...

I have a Renault 5 T2 that runs up to 20 psi of boost. it has 1400cc and 6.6:1 CR (and about 12 hp off boost I think). A naturally aspirated lotus is way more fun. But of course the R5 is really 70's turbo technology.

TomR

Man, I'd love a BDG! Is it 2 litre?

I also have a 2 litre BDG in my Elan which is great fun. I would agree with Tom turbo charging would feel remote compared to normally aspirated power.

I ran a 1760 turbo twincam in the mid 70's. It used std 1600 crank and rods with about 8:1 CR.
No problems with head gaskets and rev limit was kept to 6500.
Torque was amazing but there was some lag as it was a suck through system.
Dave

Yes, the current engine is a 2L: aluminum Nicasil Steve Jennings block, Swindon BDG head and built out by MWE on Long Island. It'd make 245hp if I could get a bigger exhaust to fit. I had the car on the road with an iron block BDA year ago but it has been apart since probably 2006... Really looking forward to having it back on the road this summer. I'll probably post pictures eventually. I recently took the BDA over to MWE as well - he dyno'd it Friday and saw 200 hp / 160 ft-lbf from 1.7 - so now I have a spare! Tom

Hi Tom
Is that a 2 seater or plus 2 I would love to see some pictures.
I recently refreshed my engine after a disaster in France my cam belt let go, pistons hit valves but while it was apart I played with compression ratio, squish clearance and valve timing I also had my valve buckets D L C'd net result

Mine is a '69 S4SE, originally a 36-series coupe but converted to ragtop before I got it. Lot of TTR chassis parts including a reinforced chassis Tony modified to my drawings to fit the T5 tranny properly.

Attached are pics from last fall, fitting the drivetrain (blurry, sorry, but you get the idea) and the body hanging from the ceiling. They're together now and just details to finish before it's on the road

Maybe it's time to start a BD club offshoot!

Looks like a whole lot of fun packed into that garage!

Its great that the car looks stock fun will be had!

john.p.clegg wrote:I think it was 2006 when I fitted a "blower" driven off the crankshaft...went like stink but the drive was problematic...

John

The attachment blower.JPG is no longer available

Was it running straight from the crankshaft of via a gearbox of sort increasing the rotational speed? I have a similar setup on a Jag engine, admittedly larger capacity and lower RPM, but it is meant to run about 30 000 rpm to sustain flow at even a moderate pressure (5 psi, 6 at the most)...

No,my Heath-Robinson affair was...



John

Saw this video - You don't need to turbo a Twin Cam when you can get 290HP out of a humble turbocharged kent OHV crossflow!

Something perversely satisfying in getting so much out of so little. Amazing engine the humble crossflow. I recently purchased a cheap 1.6L Kent crossflow out of all things a Bobcat 742 Skidsteer! In the industrial application it uses a chambered head, an updraft carburettor and is governed at 3,000RPM so it's barely been used. There was even a Diesel version of the Kent available!

https://www.youtube.com/watch?v=qKushGO5hcc&t=73s (there's a picture of the engine at 0.19 min)

https://www.youtube.com/watch?v=ZsebzrVNs2k

I imagine it would go even better in a lighter Elan.