Fiat Coupe, Lexus V8 and a Mazda MX5
Discussion
Thanks for the input 
I'll be cutting most of the bulkhead out of the coupe, cutting the coupe gear cable / exhaust tunnel out and replacing it with the complete mx5 tunnel / rear section including chassis rails and fuel tank which sits neatly in the rear deck.
Obviously the coupe pedal plate / pedals / servo will be no good in this application so I'll be using most of the mx5 bulkhead.
The coupe scuttle will be mostly cut away and I know how flimsy these cars are at the best of times let alone without cutting the hell out of it so much space framing will need to be done.
Effectively the (second) bulkhead will be set 200mm further back and using the mx5 pedal box (with clutch pedal)
The seats will use modified mx5 mounts and also be fitted 200mm further back, there will be no rear seats as the mx5 fuel tank fits up on top.
The dash support bar (coupe one) will sit 200mm further back on the space framing and a modified coupe dash will sit on that suitably dressed into the surrounding area.
The lexus slush box will be replaced eventually as it's about at its limit at 500bhp and associated torque. Hopefully to be replaced with the 8 speed ISF box with a fully programmable flappy paddle shift or the popular bmw Getrag conversion depending on funds.
500bhp from the 1uz Lexus engine is completely different to 500bhp from a stressed 2.0 engine.
The V8 will still be extremely civilised day to day and there is scope to go much further with tuning.
Being all alloy it is in fact lighter than the coupe drive train and the weight spread throughout the car to achieve greater balance.
I do know how good the coupe is and I love it so. That's why I have another one which is stock (and handy for reference)
There is no other reason for doing it other than I just want to. I'm. Building the coupe that I want it to be. It will be awesome to compare it with similar powered original cars.
I'll be cutting most of the bulkhead out of the coupe, cutting the coupe gear cable / exhaust tunnel out and replacing it with the complete mx5 tunnel / rear section including chassis rails and fuel tank which sits neatly in the rear deck.
Obviously the coupe pedal plate / pedals / servo will be no good in this application so I'll be using most of the mx5 bulkhead.
The coupe scuttle will be mostly cut away and I know how flimsy these cars are at the best of times let alone without cutting the hell out of it so much space framing will need to be done.
Effectively the (second) bulkhead will be set 200mm further back and using the mx5 pedal box (with clutch pedal)
The seats will use modified mx5 mounts and also be fitted 200mm further back, there will be no rear seats as the mx5 fuel tank fits up on top.
The dash support bar (coupe one) will sit 200mm further back on the space framing and a modified coupe dash will sit on that suitably dressed into the surrounding area.
The lexus slush box will be replaced eventually as it's about at its limit at 500bhp and associated torque. Hopefully to be replaced with the 8 speed ISF box with a fully programmable flappy paddle shift or the popular bmw Getrag conversion depending on funds.
500bhp from the 1uz Lexus engine is completely different to 500bhp from a stressed 2.0 engine.
The V8 will still be extremely civilised day to day and there is scope to go much further with tuning.
Being all alloy it is in fact lighter than the coupe drive train and the weight spread throughout the car to achieve greater balance.
I do know how good the coupe is and I love it so. That's why I have another one which is stock (and handy for reference)
There is no other reason for doing it other than I just want to. I'm. Building the coupe that I want it to be. It will be awesome to compare it with similar powered original cars.
Edited by Steve20vt on Friday 15th July 21:52
To add, sorry Nigel, didn't see it was you.
I haven't posted anything on fccuk as I can't face the hate from some folk on there.
I love your car it is extremely well set up and I know how well it performs. I take my hat off to you.
The Fiat coupe is a car that is now starting to climb in value and i know I'll get stick for cutting one up.
Perhaps when this is finished you could see for yourself how it compares to your animal round a track?
I haven't posted anything on fccuk as I can't face the hate from some folk on there.
I love your car it is extremely well set up and I know how well it performs. I take my hat off to you.
The Fiat coupe is a car that is now starting to climb in value and i know I'll get stick for cutting one up.
Perhaps when this is finished you could see for yourself how it compares to your animal round a track?
mx5 diff / shafts and hubs won't be used.
I'll use the mx5 subframe and suspension , lexus diff case, supra TT diff, lexus shafts modified to fit rx7 CVS into the mx5 uprights then to RX7 outer hubs (5x114.3 same as the lexus)
People do use the mx5 rear ends for some v8 applications with some success but mostly the Americans fit mustang rear ends.
I know of a few mx5s using bmw diesel boxes and diffs but one is having issues with shafts shearing but I think that's Due to the steel his custom shafts are made from.
One other thing of note is the coupe engine is capable of serious power, in Brazil those lads have been making over 700bhp. How long for I don't know.
I do know you can't go much more than 360bhp on a coupe engine without going forged.
The Toyota v8 was originally designed to be a race engine. And unopened one can run over 400bhp reliably.
I know of a few drift cars using the 1uz v8 unopened from donor cars that have done over well over 200k miles running silly power.
The 200sx box is chewed up by the v8 in no time.
I've had lots of s13/14s my last running 430bhp a few years back. They just don't last long strapped to the back of the big Toyota V8.
The supra r154 box is good but hideously expensive and a friend has broken 2 of them now with his V8 supra.
For me the standard auto will have to do, I know it goes against our principles. But it works, it's quite slim and it'll almost handle the power I want to start with.
And for the most part I won't have to re mortgage the house to get the power I'm after.
I'll use the mx5 subframe and suspension , lexus diff case, supra TT diff, lexus shafts modified to fit rx7 CVS into the mx5 uprights then to RX7 outer hubs (5x114.3 same as the lexus)
People do use the mx5 rear ends for some v8 applications with some success but mostly the Americans fit mustang rear ends.
I know of a few mx5s using bmw diesel boxes and diffs but one is having issues with shafts shearing but I think that's Due to the steel his custom shafts are made from.
One other thing of note is the coupe engine is capable of serious power, in Brazil those lads have been making over 700bhp. How long for I don't know.
I do know you can't go much more than 360bhp on a coupe engine without going forged.
The Toyota v8 was originally designed to be a race engine. And unopened one can run over 400bhp reliably.
I know of a few drift cars using the 1uz v8 unopened from donor cars that have done over well over 200k miles running silly power.
The 200sx box is chewed up by the v8 in no time.
I've had lots of s13/14s my last running 430bhp a few years back. They just don't last long strapped to the back of the big Toyota V8.
The supra r154 box is good but hideously expensive and a friend has broken 2 of them now with his V8 supra.
For me the standard auto will have to do, I know it goes against our principles. But it works, it's quite slim and it'll almost handle the power I want to start with.
And for the most part I won't have to re mortgage the house to get the power I'm after.
Edited by Steve20vt on Friday 15th July 22:16
These Polish lads did a rear wheel drive conversion using a 6 pot BMW engine and box.
If you look how far the engine is set back in the coupe bay you'll see what I'm aiming for.
Although the interior in theirs probably didn't have any home comforts, they do have a single wiper though!
But that's where I'm going to have the V8 sat.
https://youtu.be/tQ1FjYkwKBY
If you look how far the engine is set back in the coupe bay you'll see what I'm aiming for.
Although the interior in theirs probably didn't have any home comforts, they do have a single wiper though!
But that's where I'm going to have the V8 sat.
https://youtu.be/tQ1FjYkwKBY
Some build threads that I found quite inspirational.
https://forums.probetalk.com/showthread.php?t=1701...
The rear wheel drive probe
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
A lexus / Renault espace body swap
https://grassrootsmotorsports.com/forum/build-proj...
An original fiat coupe gets similar treatment.
https://grassrootsmotorsports.com/forum/build-proj...
An old volvo p1800 gets a Miata swap and and a Ford V8
https://forums.probetalk.com/showthread.php?t=1701...
The rear wheel drive probe
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
A lexus / Renault espace body swap
https://grassrootsmotorsports.com/forum/build-proj...
An original fiat coupe gets similar treatment.
https://grassrootsmotorsports.com/forum/build-proj...
An old volvo p1800 gets a Miata swap and and a Ford V8
A few pics of the donors.
The lexus has been so good I've MOTd it again. I can see me ending up buying another to hack up for the bits!
My plan is to develop the engine and get it producing the goods before it eventually ends up in the coupe.
There is also the actual engine that will find its way into the coupe.
This one is a 1991 large rod 1UZ, the one everyone wants as the later engines came with weaker skinny rods.
It's been rebuilt and already run in. Although the heads have just been donated to a friend for his monster 1000bhp plus monster!
The lexus has been so good I've MOTd it again. I can see me ending up buying another to hack up for the bits!
My plan is to develop the engine and get it producing the goods before it eventually ends up in the coupe.
There is also the actual engine that will find its way into the coupe.
This one is a 1991 large rod 1UZ, the one everyone wants as the later engines came with weaker skinny rods.
It's been rebuilt and already run in. Although the heads have just been donated to a friend for his monster 1000bhp plus monster!
Interesting project, I suspect it will be heavier overall when it's done and whether the front to rear ratio changes much remains to be seen I suppose.
If the weight is an issue i'd be putting the contents of both the original 20vt then the lexus/MX5 onto a trailer and visiting the local weighbridge a couple of times, but I suspect it's not about that
Personally i'd get the rear subframe/suspension, driveshafts and diff from a Dedra integrale or Q4 as it bolts straight on, they have either a torsen or a lockable open diff so you could go drifting (yeehah!) but that's just me.
Looking forward to seeing the progress.
If the weight is an issue i'd be putting the contents of both the original 20vt then the lexus/MX5 onto a trailer and visiting the local weighbridge a couple of times, but I suspect it's not about that
Personally i'd get the rear subframe/suspension, driveshafts and diff from a Dedra integrale or Q4 as it bolts straight on, they have either a torsen or a lockable open diff so you could go drifting (yeehah!) but that's just me.
Looking forward to seeing the progress.
Evoluzione said:
Interesting project, I suspect it will be heavier overall when it's done and whether the front to rear ratio changes much remains to be seen I suppose.
If the weight is an issue i'd be putting the contents of both the original 20vt then the lexus/MX5 onto a trailer and visiting the local weighbridge a couple of times, but I suspect it's not about that
Personally i'd get the rear subframe/suspension, driveshafts and diff from a Dedra integrale or Q4 as it bolts straight on, they have either a torsen or a lockable open diff so you could go drifting (yeehah!) but that's just me.
Looking forward to seeing the progress.
I did think of the Dedra set up to begin with. But finding the bits is not easy compared to bits I can find for pennies over here. If the weight is an issue i'd be putting the contents of both the original 20vt then the lexus/MX5 onto a trailer and visiting the local weighbridge a couple of times, but I suspect it's not about that
Personally i'd get the rear subframe/suspension, driveshafts and diff from a Dedra integrale or Q4 as it bolts straight on, they have either a torsen or a lockable open diff so you could go drifting (yeehah!) but that's just me.
Looking forward to seeing the progress.
Plus I know the Toyota parts can take serious power and abuse.
The weight will be an issue and I'm having to be mindful of this through the build.
The standard coupe weighs in at 1360kg (weighed on the weigh bridge at work)
The lexus engine and auto box comes in at 300kg fully dressed with air con compared to the 270 odd kg of the coupe drive train.
Ideally I'm aiming for a total weight of 1260kg. Whether or not I make that is a different thing
I have some crane scales so I'll be weighing various bits as they go on.
Steve20vt said:
If I can get near the targets of 590bhp and 1260kg I'll be ecstatic.
Even at 1400kg it would be the same power to weight ratio as a Lamborghini Gallardo lp550. Which is nice.
That's turbo territory, adding those and everything else would see a huge weight gain.Even at 1400kg it would be the same power to weight ratio as a Lamborghini Gallardo lp550. Which is nice.
I'm assuming you're putting the fuel tank in the boot? There'll only be room for a small one underneath which won't get you far with 4000ccs pulling from it...
As yet nothing has been cut. I've just been taking measurements and assessing the fitment issues.
I know how I want it to go together. I'm heading off on holiday for a fortnight so hopefully I'll be able to get through the IVA manual and see if I can come close to getting the car road legal.
Then when I'm back I'll spend some time stripping the practice vessel.
Rather than hacking up a nice coupe I'll be mocking the thing up using a Fiat Marea, the floorpan is the same as the coupe with identical engine bays so it's ideal to practice with.
I know how I want it to go together. I'm heading off on holiday for a fortnight so hopefully I'll be able to get through the IVA manual and see if I can come close to getting the car road legal.
Then when I'm back I'll spend some time stripping the practice vessel.
Rather than hacking up a nice coupe I'll be mocking the thing up using a Fiat Marea, the floorpan is the same as the coupe with identical engine bays so it's ideal to practice with.
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