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Denis247
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Post by Denis247 »

Nice to see someone else making good use of these underrated cars, though mine's a little older than yours....no rust, no slowing for corners and they look good.

A few points that may or may not apply:

Have you considered your diff?, both ratio and strength. You're going from a small engine screamer to a lazy torque-filled lump.

Keeping you gearbox and diff will mean your speedo will read ok, any changes and it may need recalibrating. Changing gearbox may affect the gearstick position.

Revcounter will need recalibrating.

Engine will be a tight fit, what's your exhaust plans?.

Cooling will need to be sorted, both water-wise and air around the engine.

Lots of other little things I'm sure you'll sort out.

Good luck with your project and I look forward to seeing updates here.


Lotus Elite 4.6 Spydersport 'Donington' conversion

kiwicar
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Post by kiwicar »

Hi
while the jag produces good torque across the rev range, it is not a rover that runs out of puff at 5.5K revs. I would not gear it too high as the jag will rev to 7.5K and really is most fun above 4000 revs I really would keep it pretty low geared to keep it fun.
Best regards
Mike
poppet valves rule!

Ozzy_Uk
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Post by Ozzy_Uk »

kiwicar wrote:Hi
while the jag produces good torque across the rev range, it is not a rover that runs out of puff at 5.5K revs. I would not gear it too high as the jag will rev to 7.5K and really is most fun above 4000 revs I really would keep it pretty low geared to keep it fun.
Best regards
Mike
this was the reason for the choise of the Jag lump...

it revs the same as the lotus 912 lump... (circa 7000rpm on the safe side)... definately wouldnt describe the jag lump as lazy...

chap on pistonheads XKRacer - tony, has a ITB'd one thats over 500bhp nat-asp and revs to nearly 8500!!

this is from his build:
Image

he also added a manual box...
http://www.ppcmag.co.uk/forum/viewtopic ... 35&start=0

it will be pretty much the same speed per RPM wise, i just want to be able to chuck it through the gears faster :)

i will be using the Supra LSD (had my old diff reconditioned after i did my 2nd track day and it started whining like a bitch ) :) its a straight swap on the Excel...

good to see another owner on here!

Hi Denis!
any info on your car?

Oz
4.0l supercharged Jaguar Lotus Excel V8... (in progress) 550bhp/tonne - target.

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dbv8
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Post by dbv8 »

Nice looking project.
I will leave all the technical stuff to the other guys :oops:

As for aims of 0-100 in 10 seconds then why not?
Power to weight seems like its going to be adequate. All comes down to grip and gearing after that really.

For some comparison, my TVR hits 100 in 7.5 now. Weighs in at about 1150kg with me on board. Only 275bhp @ wheels NA but boosted by a proper 100 shot of nitrous. The Mickey Thompson street ETs help also :wink:
10.612 @ 129.77
176.5 standing mile.

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Post by Ozzy_Uk »

dbv8 wrote:Nice looking project.
I will leave all the technical stuff to the other guys :oops:

As for aims of 0-100 in 10 seconds then why not?
Power to weight seems like its going to be adequate. All comes down to grip and gearing after that really.

For some comparison, my TVR hits 100 in 7.5 now. Weighs in at about 1150kg with me on board. Only 275bhp @ wheels NA but boosted by a proper 100 shot of nitrous. The Mickey Thompson street ETs help also :wink:
sounds like fun :)

my car is 1140kgs wet, with full interior... one of the chaps on the excel forums recently stripped his car out to race, and took out 105kgs of sound deadening material, not including the leather pieces, or rear seats!!! lol!

i am going to plexi-glass the side and rear windows of mine, try to get weight down lower, and dry weight to about 800kgs pre roll cage...

target for me mainly is constant acceloration, about 1s per 10mph is fine, 60 in 6s is what it did before, but 140 in 14s would be ideal, and the main thing about this car is the way it handles, with 160bhp engine, i was quicker arround brands hatch indy circuit than a ford GT (2006 car) much to the annoyance of the owner...

admitadly his car was stock, mine has coil overs, bigger brakes, and super sticky tyres (R888s at the time), R1-Rs now...

still was ammusing...

could do 58s laps of brands in stock format...

in the damp/wet 1:00 ish...

see here:
4.0l supercharged Jaguar Lotus Excel V8... (in progress) 550bhp/tonne - target.

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Post by Jono FD3 »

I have to say I love the idea of an old lotus going like a super car today, so good luck with the project...... but to be brutaly honest with you, if you are going to the expence of rebuilding the W58 box and having an adapter made it seams silly not to get a 154 as that will not need to be rebuilt (unless it's had a realy hard life!) and just get the adapter plate made, would work out cheeper than getting everything sorted for the 58 along with a rebuild and then smashing the gear set and then having to pull everything back out to rework for the 154 throwing twice as much money and time at it :(

at the end of the day you are asking for the box to cope with twice as much power and torque than it was designed to take.... I know track work isn't as hard on the running gear as sprint or drag, but it's the torque that will kill the box, and I can't see you not using WOT in 2nd gear coming out of a slow corner!!

My honest opinion is play it safe and know you can use the power with out thinking will the box take it?

Jono

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Post by Ozzy_Uk »

Jono FD3 wrote:I have to say I love the idea of an old lotus going like a super car today, so good luck with the project...... but to be brutaly honest with you, if you are going to the expence of rebuilding the W58 box and having an adapter made it seams silly not to get a 154 as that will not need to be rebuilt (unless it's had a realy hard life!) and just get the adapter plate made, would work out cheeper than getting everything sorted for the 58 along with a rebuild and then smashing the gear set and then having to pull everything back out to rework for the 154 throwing twice as much money and time at it :(

at the end of the day you are asking for the box to cope with twice as much power and torque than it was designed to take.... I know track work isn't as hard on the running gear as sprint or drag, but it's the torque that will kill the box, and I can't see you not using WOT in 2nd gear coming out of a slow corner!!

My honest opinion is play it safe and know you can use the power with out thinking will the box take it?

Jono
fair point, maybe my research into the W58 has not been thorough enough... i just dont want the hassle of having to mess about swapping gearboxes as the Chassis is VERY tight around it

pic:
Image

with slant 4 engine
Image
(it basically had half a V8 in it to start with!)
Image

i really really dont want to be cutting bits out of the chassis...

there could be some merrit in electronically limmiting torque to sub 350lb/ft then, and adjusting the map for max power rather than torque...

dialing it all down and keeping it safe, but ensuring we have max torque from lowest to highest possible RPM at a near constant level across the whole rev range...

also i believe the R154 is considerably heavier than the W58, i read stories of 450bhp motors running with W58s fine, and 300bhp motors breaking R154s as well as W58s... the weak spot seems to be the input shaft on the W58, and other common issue is apparently 3rd...

i am in the mind set of stick with what you know at the moment, i have a friend who can rebuild and uprate the W58 for not much money, vs an unknown R154 which i would then have to have upgraded which is circa £600-2000 depending on bearing quality and friction coatings...
Last edited by Ozzy_Uk on Thu Apr 26, 2012 5:36 pm, edited 1 time in total.
4.0l supercharged Jaguar Lotus Excel V8... (in progress) 550bhp/tonne - target.

mgbv8
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Post by mgbv8 »

Welcome Oz!!

looks like a cool project. Mental is good. We like Mental on here. 8)

Perry Stephenson

MGB GT + Rover V8

9.62 @ 137.37mph

Now looking for 8 seconds with a SBC engine

http://www.youtube.com/watch?v=nVscbPHgue0&list=UUqIlXfSAoiZ--GyG4tfRrjw



https://www.youtube.com/watch?v=eg3avnsNKrc&index=2&list=FLqIlXfSAoiZ--GyG4tfRrjw

Denis247
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Post by Denis247 »

good to see another owner on here!

Hi Denis!
any info on your car?

Oz[/quote]

Hi Oz.
Mines nowhere near your intended spec, I just wanted a little better road car, mechanical-wise, than the standard one.
Had my 1976 Elite for over 30 years now. Many moons ago Spydersport did a special chassis for the Elite/Eclat (The Donington) that accepted the Rover V8 engine and Jaguar XJ diff. & I modified it further to take coil-overs. Spyder quoted it would take 6 people or a fork-lift to lift my body off to change the chassis, I managed it on my own with just two jacks and some dexion 'scaffolding' (how hard can it be?)
I originally fitted the 3.5 but bought a new 4.6 short engine and new heads when they came out. Currently the heads are large valve and flowed, running a 216 cam and 500cfm carb. Unfortunately due to tight space I have to use block-huggers, rest of exhaust self-built. Still not bad (13.8 1/4 @ 104) but I'll give you plenty of room if ever I see you coming up behind me!.
Tried the 3.31 jag diff but found 1st gear too short so currently run the 3.07 powerlock. Using the std Rover LT77 gearbox with short gearchange linkage.
Had my rad converted to 4 core, and took away that bolt-on part of the bulkhead that just shields the heater inlets so that air could exit the engine bay better.
Lots of other little mods inc. recalibrated the speedo (using magnets!), and revcounter myself.
I've kept the exterior standard, but the result is a much nicer to drive 4-seater no-rust car that looks ok and handles well.
Good examples of these cars are going cheaply these days and are basically ok, they handle well and look good (IMHO), but they're totally better with more power.
So my car's more of a modified road car whereas your's is more of an extreme project. I wish you well with it and look forward to seeing it's progress here.
Denis
Lotus Elite 4.6 Spydersport 'Donington' conversion

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JSF55
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Post by JSF55 »

Mad is good ! i was just going to suggest a jag rear end ! the low ratio diffs are easy too come by, probably a xjs init will do the job ? and narrow the lower arms and driveshafts too suit, the cobra guys luv em :)
So thats where it went !

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Post by mgbv8 »

With those weights and expected power output I dont see why you wont exceed the mph per second target in a straight line. But you will need sticky tyres to do it ?? :)

Perry Stephenson

MGB GT + Rover V8

9.62 @ 137.37mph

Now looking for 8 seconds with a SBC engine

http://www.youtube.com/watch?v=nVscbPHgue0&list=UUqIlXfSAoiZ--GyG4tfRrjw



https://www.youtube.com/watch?v=eg3avnsNKrc&index=2&list=FLqIlXfSAoiZ--GyG4tfRrjw

Denis247
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Post by Denis247 »

JSF55 wrote:Mad is good ! i was just going to suggest a jag rear end ! the low ratio diffs are easy too come by, probably a xjs init will do the job ? and narrow the lower arms and driveshafts too suit, the cobra guys luv em :)
They're available and strong but massively heavy.
Lotus Elite 4.6 Spydersport 'Donington' conversion

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Post by Ozzy_Uk »

mgbv8 wrote:With those weights and expected power output I dont see why you wont exceed the mph per second target in a straight line. But you will need sticky tyres to do it ?? :)
normal tyre of choise is R1-R, which i run on this car and on my MGF...

the MGF is my wifes "fun" car, which she had the head ported and polished, big cams (633s), VERY loud exhaust, 40mm lowering knuckles, adjustable gaz suspension, emerald ECU, veriers, and performance panel filter... Rolling roaded at 138bhp, which over the stock 108bhp was a nice improvement :) its auto as she only has an auto license so didnt want to go too mad as the CVT gearbox on it can only handle about 130lb/ft reliably... so its pretty much where we want it for her... 0-60 is about 5.5-6s, will do over 130mpg and its returning 40mpg :) its perfect for her...


as for the Excel would rather stick with the colin chapman "add lightness" approach, and restrict the power to the engine, but have a great map with very linear torque/progressive power than go all out massive HP and have terrible driving charecteristics...

i love the 3.9:1 diff, makes for great acceloration, the auto version of the car used a 3.7:1 which might be a good swap, but not sure if they did an LSD version of that...

still hoping i can get the W58 box to work with this kit initially... guess i will start it at about 400hp, and as i crank it up to the target over time then look at replacing the gearbox when it eventually gives up further down the line when i have a bit more money/time to play with...

dont want to be adding Kg's for no good reason :) especially if i have gone to the trouble of binning window motors, heaters, interior, rear seats, sound deadening, glass, etc...
4.0l supercharged Jaguar Lotus Excel V8... (in progress) 550bhp/tonne - target.

Ozzy_Uk
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Post by Ozzy_Uk »

Denis247 wrote:
Ozzy_UK wrote:good to see another owner on here!

Hi Denis!
any info on your car?

Oz
Hi Oz.
Mines nowhere near your intended spec, I just wanted a little better road car, mechanical-wise, than the standard one.
Had my 1976 Elite for over 30 years now. Many moons ago Spydersport did a special chassis for the Elite/Eclat (The Donington) that accepted the Rover V8 engine and Jaguar XJ diff. & I modified it further to take coil-overs. Spyder quoted it would take 6 people or a fork-lift to lift my body off to change the chassis, I managed it on my own with just two jacks and some dexion 'scaffolding' (how hard can it be?)
I originally fitted the 3.5 but bought a new 4.6 short engine and new heads when they came out. Currently the heads are large valve and flowed, running a 216 cam and 500cfm carb. Unfortunately due to tight space I have to use block-huggers, rest of exhaust self-built. Still not bad (13.8 1/4 @ 104) but I'll give you plenty of room if ever I see you coming up behind me!.
Tried the 3.31 jag diff but found 1st gear too short so currently run the 3.07 powerlock. Using the std Rover LT77 gearbox with short gearchange linkage.
Had my rad converted to 4 core, and took away that bolt-on part of the bulkhead that just shields the heater inlets so that air could exit the engine bay better.
Lots of other little mods inc. recalibrated the speedo (using magnets!), and revcounter myself.
I've kept the exterior standard, but the result is a much nicer to drive 4-seater no-rust car that looks ok and handles well.
Good examples of these cars are going cheaply these days and are basically ok, they handle well and look good (IMHO), but they're totally better with more power.
So my car's more of a modified road car whereas your's is more of an extreme project. I wish you well with it and look forward to seeing it's progress here.
Denis
sounds like a fantastically usable fun car :) brilliant! any pics/build blog?

my car is going to be pretty much a track day special... with added "lightness" :twisted:

not going for top speeds, but will have 'em in the corners :wink:
4.0l supercharged Jaguar Lotus Excel V8... (in progress) 550bhp/tonne - target.

Denis247
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Post by Denis247 »

Ozzy_Uk wrote:
Denis247 wrote:
Ozzy_UK wrote:good to see another owner on here!

Hi Denis!
any info on your car?




sounds like a fantastically usable fun car :) brilliant! any pics/build blog?

my car is going to be pretty much a track day special... with added "lightness" :twisted:

not going for top speeds, but will have 'em in the corners :wink:
Oz, I've put a couple of pics here, (wanted to take it out of the Engines forum and into the Cars forum)

http://www.v8forum.co.uk/forum/viewtopi ... 0709#80709
Lotus Elite 4.6 Spydersport 'Donington' conversion

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