The Lotus Grand Tourers

Totally agree bash....

Conversions obviously aren't everyone's cup of tea, but when people ask about them on the forums, people should at least be truthful and accurate in their criticism, and in pointing out the pro's (performance, noise, delivery) and cons (gearing, thirst) and not just make stuff up about weight and "ancient design". The Rover V8 is almost exactly the same weight as the 912 -it makes not one iota of difference to the handling of the Lotus.

Gearing is troublesome. Thirst is annoying. Performance is not.

I guess the point I am making, is that the handling is unaffected, because they weigh the same. Whether you like the concept or not is up to each persons personal tastes.

Can mike really have a 2.5 stroker 912 that does more than 300lb ft?

impressive....

Just curious, what mpg are you getting dunc, with what sort of fueling and rear axle ratio.
Bash

As a serious aside.... If you are dead set on getting a bigger lump in, you are best sticking with Toyota as this with a bit of bell housing matching and a clutch hybrid could have you halfway to getting a lump onto the supra gearbox.

Other alternatives: 3 litre twin turbo from the late model supra/soarer RZ ( if the engine bay is big enough.)
4 litre v8 lump from Lexus has been done before.

It depends how you drive and what you want?

I know mrcoolA was very happy with his race lump 912 as he (did) redline his a lot.
I want a torque laden 912 cos I am fed up with being blown away at the traffic lights by 1.2 corsas until I hit the power band, then it sounds like I'm trying too hard - so am having this built which will hit peak torque much lower than 5k rpm.

My point is there are many ways to skin a cat.... How deep are your pockets?

A cheap excel is a money pit and a more expensive one will cost less in the long run.
Mine was cheap to give me something to do. I can afford it as I have no kids, no girlfriend or wife, no house, no social life and am always offshore.
If I had a choice I would take the "getting a life" but Ethel is my mistress for now

dunc wrote:
Can mike really have a 2.5 stroker 912 that does more than 300lb ft?

impressive....

Depends how big you budget is?
I know for mine I will be looking at at least 220ftlb and the thick side of 260 bhp.
Lots of stuff on mine is untested though so it will be a case of see what happens and how well each part compliments the other

It's still on its 4.1:1 diff which is waaaay to short. I bought a 3.73 diff and gave it to a salisbury specialist to have another diff built up (with a 3.01:1 CW&P and a powerlok) which should improve things. Still waiting on that tho....

At the moment it is motorbike fast to 100mph, with 1/4's in low 13's, but at 5750rpm your doing 124. Changing the diff to 3.01:1 will give a relaxed cruise and better mpg and a top speed around 155-160.

On current gearing mpg is a bit of a sore point. 18 is possible on a motorway if you are gentle, average drops to single figures away from motorways if you boot it everywhere.

by fueling, do you mean induction or premium/regular?

I run it on normal fuel.

Induction is an Edelbrock 500cfm quad barrel, on an Edelbrock performer manifold through big valve modded heads. Engine is a lightened and balanced 4.6 built by V8 developments of Lincoln.

I have bought an Eaton M90 supercharger and a barry grant 575cfm demon blow-through quad barrel carb, but they remain on the shelf of my workshop at the moment. Will want to sort the gearing first to give more relaxed cruising. MPG in the 20's coupled with the faster top end should be achievable.

i still rate the AJ26/AJ28 V8...

light weight (160ish kgs for the block without gearbox), 320bhp N/A stock (without Cats, 290 with), 7000rpm, 26-28mph in significantly heavier cars...

cosworth bottom end that is good to about 600bhp out of the box (with the right balancing)...

can be tuned (relatively) cheaply, and makes a lovely noise when supercharged (kits available cheaply too)

want to keep my N/A initially though, and try to get it up to 350-400bhp with remap, cams, and good exhaust/induction, and some minor head/valve work...

oh and you can buy an S-Type V8 for £1100-1300 as a donor... and i bought an M112 supercharger complete with manifolds and charge coolers for this engine (total bolt on solution) for £300

Sounds like a good engine. Mat's Lexus V8 also sounds like it will be a really nice car.

I've seen an elite with a Chev LT V8 fitted. I know very little about Chevrolet V8's, but would assume if the iron LT fits in, then the alloy LS1 to LS3 would also fit? That could be HUGE fun and massively tuneable in bang per buck....

One thing to remember with the higher spinning V8's.... although they can rev towards 7K, and will theoretically work with an standard excel/eclat drive ratio, your fueling 8 cylinder on cruise, which will give the same eye watering MPG that I'm getting.

A cruise of 3000rpm at 70 is distinctly sub optimal for a V8. You'll want to alter the gearing towards 2250, even if your 7K V8 is offering 150mph on standard gearing. You'll want it overdriven as much as you can.

D

I'm running a 3.23:1 diff (BTR Hydratrac) so very relaxed cruising, especially as top gear is "double overdriven" (5-speed Tremec TKO 600). I seem to remember that it's doing ~70 at ~2300 rpm, but I haven't driven it since last summer. Haven't dared worked out fuel consumption yet, but I expect it will be awful if driven hard!

What gearbox are you using Dunc?

Pete

dunc wrote:
I've seen an elite with a Chev LT V8 fitted. I know very little about Chevrolet V8's, but would assume if the iron LT fits in, then the alloy LS1 to LS3 would also fit? That could be HUGE fun and massively tuneable in bang per buck....

D

It fits!!

Pete

The Getrag 265. Its the best one available and was standard fit on the eclat S2.

1:1 4th and 0.82 overdriven 5th.


if your getting 2300rpm at 70mph, I'd say that was just about perfect...

D

mmmmmmm. Its the rear axle ratio that makes all the difference to mpg. The 390se had about 3.1;1 I think, but even tho it was tuned I could get better fuel consumption than with a standard 350i. if I was very careful on the m/way I could get almost 30 mpg, but 27 was easyily attainable. Well into single figures on a track day tho. I remember brimming the tank at the filling station adjacent to donington before going in, but needing to fill up again to get home. but it depends how you view figures like yours. If its your everyday car then its bad news, but if its a toy for high days and holidays then its just part of the cost of having fun. Im with the latter view.
I like ozzys plan, but new ecu's put me right off. the cost how that would have me crowing like the yorkshireman I am, 'HOW MUCH'. (without the 'h' of course.)

Bash

5th (top) on the Tremec is 0.64:1 - good cruising gear.

Pete

Blimey, that shows the torque of your engine, I think the LT77 in the tvr was about 0.83 overdriven from memory.
Bash

bash wrote:I like ozzys plan, but new ecu's put me right off.

Bash

I love Ozzy's plan - looking forward to seeing it. You're right about ECUs - I want to change from the GM unit I'm running at the moment to a DTA, but as well as all the rewiring it's at least another £1k.

Don't forget I've got those Rover fuel injection bits Bash - then you can get yourself a nice complicated ECU!!

Pete

My Holden does about 1850rpm at 70mph.

3:08:1 final drive and a 0.7 overdriven box with massive wheels.

booked at 28mpg on cruise from an engine thats bigger than the one in the eclat.

Fuel injection obviously helps vs the carb, but it gives me hope that 25mpg might be possible on a 3.01:1 diff in the eclat?

I work in the city of London, so I catch the train. The car is a weekend toy which gets embarassingly little use so its thirst is largely academic, but I would like it to be longer legged for trips to France etc.