Just Another F20C build... <Preview>
#21
Junior Member
Thread Starter
Join Date: Dec 2010
Location: UK, in Cambridgeshire or wherever work takes me.
Posts: 375
Total Cats: 20
I can't argue with your results at all, and I'd still kill for your car. The power must be insane. We've both just got a different philosophy on cars I think. I reckon I'll generate a fair bit of confusion regarding the other choices I'm making with this build. For example, I'll be running 185/55 r15 tyres, and spring rates around one third as stiff as many members here. All depends on what YOU want to get from the car.
That said, the clubroaster lot are still gays and I will never understand the choices they make, ha.
That said, the clubroaster lot are still gays and I will never understand the choices they make, ha.
#22
Elite Member
iTrader: (1)
Join Date: Jun 2006
Location: Warrington/Birmingham
Posts: 2,642
Total Cats: 42
I can't argue with your results at all, and I'd still kill for your car. The power must be insane. We've both just got a different philosophy on cars I think. I reckon I'll generate a fair bit of confusion regarding the other choices I'm making with this build. For example, I'll be running 185/55 r15 tyres, and spring rates around one third as stiff as many members here. All depends on what YOU want to get from the car.
That said, the clubroaster lot are still gays and I will never understand the choices they make, ha.
That said, the clubroaster lot are still gays and I will never understand the choices they make, ha.
#23
Well said. Every car guy has a vision for the project they are building. I think an important question to ask is what are you building? Will it be DD that sees the occasional track day, a dedicated track car, will you be running auto x? Soft springs lead me to believe you are buinding a fun DD type commuter.
#24
Junior Member
Thread Starter
Join Date: Dec 2010
Location: UK, in Cambridgeshire or wherever work takes me.
Posts: 375
Total Cats: 20
I should have outlined my plan and idea a little better in the first post I think. Here's a long-winded clarification (ha) of what I'm aiming for:
This car will be a daily-driven road car. I might take it on track occasionally. I'm a go-karting guy, and that tends to be where I get my track fix. I do, however, regularly go out late at night on the back roads for a thrash. I'd have a Caterham as a DD in a heartbeat if I could fit anything in one.
I bought the Miata because it didn't have much grip, and had excellent chassis balance and adjustability. For me, that makes it a lot of fun. With this build - aside from inserting an engine which I think fits the whole vibe of the car - I'm aiming to keep grip levels more or less the same, make the steering better (after driving a non-power-assisted car, I know my Miata has the potential to have excellent steering), increase the stiffness of the chassis a bit, lighten the car as much as I'm prepared to, and importantly, fully resolve the damping. The dampers I'm choosing for the car are being valved by an ex-Lotus guy, and I want the ride to be as Lotus Elise-like as possible. A particular Elise remains the most impressive car I've ever ridden in, just because it was more comfy than a Volvo, yet very well controlled at all speeds.
For those in the States, bare in mind that our roads are often a lot bumpier than yours (and yes, I have been over the pond to see for myself!). Consequently, a more softly sprung car is often preferable. Even with 185 section Yokohama AD08s, I think I'll still generate more grip than a standard Miata, if the damping is nailed. 185 section tyres are obviously lighter, and less prone to bump steer, than a wider version of the same tyre. The 6" wide OE BBS rims on this car are slightly lighter than 7" 6ULs, so I'll be keeping hold of them. In fact, I don't intend to change the exterior of the car at all.
This car will be a daily-driven road car. I might take it on track occasionally. I'm a go-karting guy, and that tends to be where I get my track fix. I do, however, regularly go out late at night on the back roads for a thrash. I'd have a Caterham as a DD in a heartbeat if I could fit anything in one.
I bought the Miata because it didn't have much grip, and had excellent chassis balance and adjustability. For me, that makes it a lot of fun. With this build - aside from inserting an engine which I think fits the whole vibe of the car - I'm aiming to keep grip levels more or less the same, make the steering better (after driving a non-power-assisted car, I know my Miata has the potential to have excellent steering), increase the stiffness of the chassis a bit, lighten the car as much as I'm prepared to, and importantly, fully resolve the damping. The dampers I'm choosing for the car are being valved by an ex-Lotus guy, and I want the ride to be as Lotus Elise-like as possible. A particular Elise remains the most impressive car I've ever ridden in, just because it was more comfy than a Volvo, yet very well controlled at all speeds.
For those in the States, bare in mind that our roads are often a lot bumpier than yours (and yes, I have been over the pond to see for myself!). Consequently, a more softly sprung car is often preferable. Even with 185 section Yokohama AD08s, I think I'll still generate more grip than a standard Miata, if the damping is nailed. 185 section tyres are obviously lighter, and less prone to bump steer, than a wider version of the same tyre. The 6" wide OE BBS rims on this car are slightly lighter than 7" 6ULs, so I'll be keeping hold of them. In fact, I don't intend to change the exterior of the car at all.
#26
Junior Member
Thread Starter
Join Date: Dec 2010
Location: UK, in Cambridgeshire or wherever work takes me.
Posts: 375
Total Cats: 20
I didn't get a chance to nip over to the shop after work today, but I did call them to get the latest news. Turns out that the heater matrix does not need to be moved in order for the engine to clear the 'rack. That's about the only update, but I think that's encouraging info for anyone wishing to go down this path in future
#28
Junior Member
Thread Starter
Join Date: Dec 2010
Location: UK, in Cambridgeshire or wherever work takes me.
Posts: 375
Total Cats: 20
Moar info re your concern about adjusting valves please.
The oil filler cap will, of course, be under the windscreen. Working out a way to get it off and top up the oil shouldn't be too hard.
Re the exhaust, as I've said, I've done a shed load of research into what these particular engines 'like' when it comes to their exhaust. Hopefully I won't have to make any compromises. Quent mentioned flattening the exhaust slightly when it transitions from one side of the drivetrain to the other to ensure decent ground clearance, but obviously maintaining the same cross sectional area to avoid a bottleneck. In theory, this sounds great, but I think maintaining EXACTLY the same cross sectional area would be very tricky in practise, and would be exactly the kind of thing that would strangle the engine if it was more than a few square mm out.
The oil filler cap will, of course, be under the windscreen. Working out a way to get it off and top up the oil shouldn't be too hard.
Re the exhaust, as I've said, I've done a shed load of research into what these particular engines 'like' when it comes to their exhaust. Hopefully I won't have to make any compromises. Quent mentioned flattening the exhaust slightly when it transitions from one side of the drivetrain to the other to ensure decent ground clearance, but obviously maintaining the same cross sectional area to avoid a bottleneck. In theory, this sounds great, but I think maintaining EXACTLY the same cross sectional area would be very tricky in practise, and would be exactly the kind of thing that would strangle the engine if it was more than a few square mm out.
#30
The top of the valve train sits just under the valve cover, If you are having to work out how to get the oil cap off, my concern is that it will be impossible to get the valve cover off to adjust valves. The valve train is rocker under camshaft, the adjusters are at the end of the rockers over the valve stems. As you can see from the picture with the guy in it (not me by the way) there is a lot of mass above the mating surface of the cylinder head to valve cover. You need a lot of clearance above the valve cover to remove it.
Just thinking out loud.
Just thinking out loud.
#33
Junior Member
Thread Starter
Join Date: Dec 2010
Location: UK, in Cambridgeshire or wherever work takes me.
Posts: 375
Total Cats: 20
After further research, I don't think it'll be necessary to adjust the valves much.... if ever.
I'll upload some photos later tonight. I have to go bale carting on the farm. Which will be SO MUCH fun, especially after a day on a construction site.
I'll upload some photos later tonight. I have to go bale carting on the farm. Which will be SO MUCH fun, especially after a day on a construction site.
#35
Junior Member
Thread Starter
Join Date: Dec 2010
Location: UK, in Cambridgeshire or wherever work takes me.
Posts: 375
Total Cats: 20
More pics and descriptions in a bit...
Descriptions, from left to right:
- New dash is in the Bentley. Looks a bit too 'new', but the brass should tarnish nicely. Quent's busy wiring it up.
- Photo taken from the (UK) passenger footwell, looking directly across the firewall, showing the clearance between the firewall and the heater box.
- Another shot of the initial cut out in the firewall.
- Looking from the engine bay back through the trans tunnel. The corner of the driver's footwell (on the left of the photo, with the lines running under it) will be cut out and reversed. This will give more room for the exhaust manifold, and also give me somewhere to rest my foot when driving, ha.
- Looking down into the engine bay. The galv tube is in the place of the steering rack. You can see where Quent has cut the crossmember. New crossmembers will be fab'd up both in front and behind the steering rack, for strength, stiffness, and for a handy place to put the battery...
Descriptions, from left to right:
- New dash is in the Bentley. Looks a bit too 'new', but the brass should tarnish nicely. Quent's busy wiring it up.
- Photo taken from the (UK) passenger footwell, looking directly across the firewall, showing the clearance between the firewall and the heater box.
- Another shot of the initial cut out in the firewall.
- Looking from the engine bay back through the trans tunnel. The corner of the driver's footwell (on the left of the photo, with the lines running under it) will be cut out and reversed. This will give more room for the exhaust manifold, and also give me somewhere to rest my foot when driving, ha.
- Looking down into the engine bay. The galv tube is in the place of the steering rack. You can see where Quent has cut the crossmember. New crossmembers will be fab'd up both in front and behind the steering rack, for strength, stiffness, and for a handy place to put the battery...
Last edited by owenwilliams; 07-14-2011 at 03:58 PM.