Big Bhp or Feel for Seven style kit car?
Discussion
ugg10 said:
Sorry, bit late to the discussion but for the road my view is that around 180hp/140ftlbs and rev to 8k with a tad under 600kg on 185/195 tyres is the sweet spot (diff around the 4:1 mark). This would be plenty quick enough and still be able to use 80% of the performance on the road if required.
So if I were to build another kit, I would go for a Zetec SE 1.7 with cams, HD springs, rod bolts and ITBs (185hp and very light) in a Raw Stiker with a close ratio type 9 (SPC Tracsport semi helical?) or if funds allow an elite sequential.
Just my 2p's worth.
Thanks Ugg, Just about where I have got to. My Striker(Sylva not raw so live real axle) will end up around 180-200bhp with the duratec engine and around 550kgs(the live axle makes it lighter So if I were to build another kit, I would go for a Zetec SE 1.7 with cams, HD springs, rod bolts and ITBs (185hp and very light) in a Raw Stiker with a close ratio type 9 (SPC Tracsport semi helical?) or if funds allow an elite sequential.
Just my 2p's worth.
It's on 195 tyres at the moment. Im toying with a Mk3 Mx5 box and custom prop to go with the duratec engine rather than a new bellhousing on the type 9. Costs will not be too dissimilar once I sell the type 9 and I much prefer the Mx5 gearbox. Should save some money in the long run too in gearbox rebuilds. I found a Mk3 box cheap in a scrappies which should be here this week. Will try it to see if it'll physically fit in the tunnel then work out fabricating mounts if it does. the Duratec engine in the Mx5 sits at a 10 degree angle towards the drivers side, so I'd need to work round that either by mounting the engine at the 10 degree angle and getting a different sump or alternatively, as im tight for space under the bonnet, I thought about mounting the engine at a 3 or 4 degree cant (which would leave the gearbox 6 or 7 degrees tilted towards the passenger side) and then fabricate a bend in the bottom of the gear shift lever to have it sit upright. Thoughts on that?
ugg10 said:
Sorry, bit late to the discussion but for the road my view is that around 180hp/140ftlbs and rev to 8k with a tad under 600kg on 185/195 tyres is the sweet spot (diff around the 4:1 mark). This would be plenty quick enough and still be able to use 80% of the performance on the road if required.
So if I were to build another kit, I would go for a Zetec SE 1.7 with cams, HD springs, rod bolts and ITBs (185hp and very light) in a Raw Stiker with a close ratio type 9 (SPC Tracsport semi helical?) or if funds allow an elite sequential.
Just my 2p's worth.
Thanks Ugg, Just about where I have got to. My Striker(Sylva not raw so live real axle) will end up around 180-200bhp with the duratec engine and around 550kgs(the live axle makes it lighter So if I were to build another kit, I would go for a Zetec SE 1.7 with cams, HD springs, rod bolts and ITBs (185hp and very light) in a Raw Stiker with a close ratio type 9 (SPC Tracsport semi helical?) or if funds allow an elite sequential.
Just my 2p's worth.
It's on 195 tyres at the moment. Im toying with a Mk3 Mx5 box and custom prop to go with the duratec engine rather than a new bellhousing on the type 9. Costs will not be too dissimilar once I sell the type 9 and I much prefer the Mx5 gearbox. Should save some money in the long run too in gearbox rebuilds. I found a Mk3 box cheap in a scrappies which should be here this week. Will try it to see if it'll physically fit in the tunnel then work out fabricating mounts if it does. the Duratec engine in the Mx5 sits at a 10 degree angle towards the drivers side, so I'd need to work round that either by mounting the engine at the 10 degree angle and getting a different sump or alternatively, as im tight for space under the bonnet, I thought about mounting the engine at a 3 or 4 degree cant (which would leave the gearbox 6 or 7 degrees tilted towards the passenger side) and then fabricate a bend in the bottom of the gear shift lever to have it sit upright. Thoughts on that?
Have you considered a 6 speed box from a RX8? These seem to be going for not that much and seems to be quite a bit stronger than a type 9.
I considered this mated to a duratec for my next kit project using an adapter plate from this site.
http://www.p9cyoplates.co.uk
I considered this mated to a duratec for my next kit project using an adapter plate from this site.
http://www.p9cyoplates.co.uk
van cleef said:
Have you considered a 6 speed box from a RX8? These seem to be going for not that much and seems to be quite a bit stronger than a type 9.
I considered this mated to a duratec for my next kit project using an adapter plate from this site.
http://www.p9cyoplates.co.uk
When looking for the box...bear in mind it might be cheaper to buy the entire Rx8 given the residual values of the stupid cars!I considered this mated to a duratec for my next kit project using an adapter plate from this site.
http://www.p9cyoplates.co.uk
Feel if you want to learn to drive the car properly, big bhp if you want to feel like a hero on a track day.
As someone has already said, IMO ~180-190bhp with short-ish gearing and good handling is perfect for a Se7en. More and you never get a clear lap on track and you can't use it all on the road, less and you always feel like it could do with a touch more.
As someone has already said, IMO ~180-190bhp with short-ish gearing and good handling is perfect for a Se7en. More and you never get a clear lap on track and you can't use it all on the road, less and you always feel like it could do with a touch more.
jeffw said:
AdamR172 said:
big bhp if you want to feel like a hero on a track day.
Seriously? Is that your considered, grown up, opinion? There comes a point where you reach a comfortable limit on Bhp for the road. Having spent a lot of time on a bike, the R6 was far more useable on the road than an R1 was, just simply because you could use the majority of power in the R6 whereas the R1 you were constantly guarding the slip. Plus it allowed a few more mistakes to be made. On a track though the R1 was certainly king although taking both to a circuit had their own characteristics which I had great fun with
Im building a 7 with 310bhp at the moment and certainly looking forward to getting it out on the road. Im also building a 165 version and will be interested to see the difference between the two on the road/track
IMHO you are looking at this the wrong way from the start
That said the Duratec is a good revy engine and you won't go far wrong
The Striker is a light nimble car and a lot can be gained from the right tyres and good brakes
This is where these cars really work, later braking, higher corner speed and good acceleration out of the bends
Having to much power compromises this as your never on full throttle always feathering and being cautious on the way out
I run a 7, it's a bit heavy and I found the Toyo CF1's wouldn't get hot enough on the road unless I drove like a maniac, if the tyres are cold you break earlier, corner slower and spin up on the way out
More power the slower you go
That said the Duratec is a good revy engine and you won't go far wrong
The Striker is a light nimble car and a lot can be gained from the right tyres and good brakes
This is where these cars really work, later braking, higher corner speed and good acceleration out of the bends
Having to much power compromises this as your never on full throttle always feathering and being cautious on the way out
I run a 7, it's a bit heavy and I found the Toyo CF1's wouldn't get hot enough on the road unless I drove like a maniac, if the tyres are cold you break earlier, corner slower and spin up on the way out
More power the slower you go
Slightly off topic I know but a few years back I was a born again biker and owned several big tourers and super bikes.
These were raise the front wheel machines with a top speed car owners only dream about, but the most "fun" that I had was
when my son reached 17 and he bought a DT125. Not wanting him out on the road without supervision and thinking that
the 1100 Kawasaki that I had at the time was overkill I bought a £300 Honda Superdream 400 twin.
I could ride that bike to the limit, the limit being 89 mph, and it's traction limited by Chen Shing tyres. Fun ? Never had fun
like it before or since.
So as for cars, I would think the same applies. My Seven has 180 bhp and I'd say that's plenty.
Paul G
These were raise the front wheel machines with a top speed car owners only dream about, but the most "fun" that I had was
when my son reached 17 and he bought a DT125. Not wanting him out on the road without supervision and thinking that
the 1100 Kawasaki that I had at the time was overkill I bought a £300 Honda Superdream 400 twin.
I could ride that bike to the limit, the limit being 89 mph, and it's traction limited by Chen Shing tyres. Fun ? Never had fun
like it before or since.
So as for cars, I would think the same applies. My Seven has 180 bhp and I'd say that's plenty.
Paul G
Edited by finishing touch on Thursday 3rd December 15:40
PaulKemp said:
IMHO you are looking at this the wrong way from the start
That said the Duratec is a good revy engine and you won't go far wrong
The Striker is a light nimble car and a lot can be gained from the right tyres and good brakes
[b]
This is where these cars really work, later braking, higher corner speed and good acceleration out of the bends
Having to much power compromises this as your never on full throttle always feathering and being cautious on the way out[/b]
I can see the argument that going for the lightest, sweetest-handling car makes sense because it feels good; but not for reasons of speed really.That said the Duratec is a good revy engine and you won't go far wrong
The Striker is a light nimble car and a lot can be gained from the right tyres and good brakes
[b]
This is where these cars really work, later braking, higher corner speed and good acceleration out of the bends
Having to much power compromises this as your never on full throttle always feathering and being cautious on the way out[/b]
On the road, your cornering speed isn't limited by grip, it's limited (almost always) by vision. So the higher cornering speed of a seven doesn't count for much, and for a super-nimble seven verses a slightly less nimble one, even less. I can corner as fast and brake as late on most roads in a tintop as I can in the Dax.
You can use the cornering and braking on track of course, but then you can also use a lot more power on track. And on track, surely more power than grip makes it more fun? If I didn't have to feather the throttle out of a hard corner, I'd feel I was missing out on something.
CrutyRammers said:
PaulKemp said:
IMHO you are looking at this the wrong way from the start
That said the Duratec is a good revy engine and you won't go far wrong
The Striker is a light nimble car and a lot can be gained from the right tyres and good brakes
[b]
This is where these cars really work, later braking, higher corner speed and good acceleration out of the bends
Having to much power compromises this as your never on full throttle always feathering and being cautious on the way out[/b]
I can see the argument that going for the lightest, sweetest-handling car makes sense because it feels good; but not for reasons of speed really.That said the Duratec is a good revy engine and you won't go far wrong
The Striker is a light nimble car and a lot can be gained from the right tyres and good brakes
[b]
This is where these cars really work, later braking, higher corner speed and good acceleration out of the bends
Having to much power compromises this as your never on full throttle always feathering and being cautious on the way out[/b]
On the road, your cornering speed isn't limited by grip, it's limited (almost always) by vision. So the higher cornering speed of a seven doesn't count for much, and for a super-nimble seven verses a slightly less nimble one, even less. I can corner as fast and brake as late on most roads in a tintop as I can in the Dax.
You can use the cornering and braking on track of course, but then you can also use a lot more power on track. And on track, surely more power than grip makes it more fun? If I didn't have to feather the throttle out of a hard corner, I'd feel I was missing out on something.
Also if you are on the limit under brakes or in corners on the road, you are a very long way from driving safely even if the 7 is less powerful... that kind of commitment is for the track.
My cars hardly a 7, but its light for a tin top and with over 700bhp per ton I can and do use the car full throttle in corners on track... hard to do on the road, but its still very fast and rewarding in corners and I ALWAYS have loads of performance spare on the road meaning I can also drive it fast rain or shine... that to me is fun
here is some on-board of my Dax Rush Hayabusa Turbo 300+bhp 540kg on slicks on a damp track just good fun!!
https://www.youtube.com/watch?v=7c_oXNVm2r8
https://www.youtube.com/watch?v=7c_oXNVm2r8
jeffw said:
Seriously? Is that your considered, grown up, opinion?
Yes :-DNah, that was too short a response, I apologise. I need to learn not to post until I have time to explain myself fully!
My point is, that I have very very very rarely seen a big power car (or big bhp/ton car) driven well on a track. The drivers of these cars tend to post good times, but they are hiding behind the power.
Personally I get a lot more satisfaction from hustling the crap out of an underpowered car than I do cruising round the corners and then booting the throttle once the car is in a straight line again.
If you are driving hard enough, ANY car has enough power to spin the wheels mid corner. It's simple physics. If you are using 99% of the available traction for cornering (ie. you are right on the limit of grip), then you apply some throttle you are asking the tyre to do more work, and it will slide. Doesn't matter if you have 300mm wide super soft sprint slicks or 155/70 Chinese ditchfinders, 80bhp or 800bhp, the same applies. And the more driving you do on the lower powered car with the less grippy tyres, the better a driver you will be if / when you do get in something with more power and more grip...
AdamR172 said:
My point is, that I have very very very rarely seen a big power car (or big bhp/ton car) driven well on a track. The drivers of these cars tend to post good times, but they are hiding behind the power.
That argument only holds if you can show that more drivers of high bhp/ton cars drive worse than those of lower bhp/ton cars. 
If in fact, it's just that many people don't get the most out of their car, (as I suspect), then the power is neither here nor there.For myself, with currently limited track experience, I know that my cornering speeds are nowhere near what they could be. But it's not because I've got too much power going out of corners, it's because I don't judge how much I can take in very well. It's true that power does mask this and let you get away with it a bit more, but I don't see how a slower car would solve the problem.
I suppose you could come to be lazy and rely on the power rather than improving your technique, which I guess is what you're saying, but then that'd be up to me, not the fault of the car. And I don't really get why it matters even then?
That's true! I can't drum up any empirical evidence (without trawling YouTube for hours, I guess), I just see a lot more 'fast' cars and think 'that should be lapping faster' than I see 'slow' cars and think similar. This may be swayed by the quantities of 'fast' and 'slow' cars you come across though, I guess...
This is how I see it, bear with me... With a slower car you're entering the corners at a speed that's easier to pick a braking point and turn in point. You have a greater margin (in terms of time, not distance) for error so you can more easily learn to be consistent and develop the skills required. If you have a bomb under your right foot ready to go off, you can still get round quickly without having to bother pushing hard in the part of the lap where it's difficult to make up time - exactly. A slower car solves the problem, in my opinion, in a few ways:
1) It'll be cheaper to run, so you can have more goes at the difficult bits of the lap for the same cost.
2) You don't worry too much about pushing hard, cos it's cheaper to fix if (when?) things go tits up.
3) From a combination of the above two, you develop your skills further.
(Slight assumption that 'cheaper' = 'slower', but that is almost always the case...)
I agree that's a 'driver thing' rather than a 'car thing', but invariably I see people spending money on straight line speed upgrades rather than 'going round the twiddly bits' upgrades in an attempt to go faster - possibly because it's guaranteed to drop lap time without any extra effort from the driver. It's human nature to want to a) take the easy route and b) go faster. But yes - it doesn't matter, everyone is different and everyone has their own preferences. I feel like I'm labouring the point, repeating myself, getting boring and taking this off topic... apologies. I've just found my sub-£1000 MX-5 to be way more fun than the 440bhp/ton Westfield I've just got rid of, and trying to convert a few more to hairdresserism :-)
This is how I see it, bear with me... With a slower car you're entering the corners at a speed that's easier to pick a braking point and turn in point. You have a greater margin (in terms of time, not distance) for error so you can more easily learn to be consistent and develop the skills required. If you have a bomb under your right foot ready to go off, you can still get round quickly without having to bother pushing hard in the part of the lap where it's difficult to make up time - exactly. A slower car solves the problem, in my opinion, in a few ways:
1) It'll be cheaper to run, so you can have more goes at the difficult bits of the lap for the same cost.
2) You don't worry too much about pushing hard, cos it's cheaper to fix if (when?) things go tits up.
3) From a combination of the above two, you develop your skills further.
(Slight assumption that 'cheaper' = 'slower', but that is almost always the case...)
I agree that's a 'driver thing' rather than a 'car thing', but invariably I see people spending money on straight line speed upgrades rather than 'going round the twiddly bits' upgrades in an attempt to go faster - possibly because it's guaranteed to drop lap time without any extra effort from the driver. It's human nature to want to a) take the easy route and b) go faster. But yes - it doesn't matter, everyone is different and everyone has their own preferences. I feel like I'm labouring the point, repeating myself, getting boring and taking this off topic... apologies. I've just found my sub-£1000 MX-5 to be way more fun than the 440bhp/ton Westfield I've just got rid of, and trying to convert a few more to hairdresserism :-)
I find myself agreeing with a lot in that; it's what lies behind my earlier post.
I've run a Fisher Fury with an R1 engine for nearly six years now, at the very shallow end if you like -427Kg wet/165-170hp: 502kg fully fuelled with me in it
Way more than quick&nimble enough on the road, can be fully wound out elsewhere; driven year-round on-road, even on wet/cold roads (educational!!) and I'm not yet at the end of learning what it can do: pure gecko-down-a-pipe capability. As I said - a scalpel, not a broadsword.
Put it this way - 20-odd Kmiles in it later, I'm not after 'more power first', that's for sure. It just remains immense fun
I've run a Fisher Fury with an R1 engine for nearly six years now, at the very shallow end if you like -427Kg wet/165-170hp: 502kg fully fuelled with me in it
Way more than quick&nimble enough on the road, can be fully wound out elsewhere; driven year-round on-road, even on wet/cold roads (educational!!) and I'm not yet at the end of learning what it can do: pure gecko-down-a-pipe capability. As I said - a scalpel, not a broadsword.
Put it this way - 20-odd Kmiles in it later, I'm not after 'more power first', that's for sure. It just remains immense fun
Edited by Huff on Saturday 5th December 00:22
I do think you are living a slight dream here. The reality is that given the state of the roads today you cannot exploit any vehicle, low powered or otherwise, without risking legal ramifications or injury to others.
Cars on trackdays are limited, frequently, by the speed of the car in front through corners. Corner speed is, by and large, dictated by tyre grip so a low powered kitcar with R888 is going to corner as fast as (or as slow as) a high powered car with R888 (as an example). The high-powered car will need to brake earlier because of the high terminal speed. The differential on a trackday between a high powered kit and a low powered kit is not going to be great but then you wouldn't expect it to be unless one of them had Aero. Working Aero will make all the difference and allow much higher corner speeds but is very frustrating as you can't overtake round corners so your advantage gets nullified pretty quickly.
Here are two videos from the Complete Kit Car day at Llandow last year. If you start them at the same time you'll see the difference between a light, low-powereed R1 Striker on decent tyres and a heavy (620Kg) high-powered (400BHP) Phoenix also on decent tyres. Remember that Llandow is very short so the high-powered cars advantage is reduced considerably. The R1 Striker is very well driven and the Phoenix has me driving (for good or bad).
https://www.youtube.com/watch?v=5mLn1s4_G-c
https://www.youtube.com/watch?v=E1LDEf6TGyo
Cars on trackdays are limited, frequently, by the speed of the car in front through corners. Corner speed is, by and large, dictated by tyre grip so a low powered kitcar with R888 is going to corner as fast as (or as slow as) a high powered car with R888 (as an example). The high-powered car will need to brake earlier because of the high terminal speed. The differential on a trackday between a high powered kit and a low powered kit is not going to be great but then you wouldn't expect it to be unless one of them had Aero. Working Aero will make all the difference and allow much higher corner speeds but is very frustrating as you can't overtake round corners so your advantage gets nullified pretty quickly.
Here are two videos from the Complete Kit Car day at Llandow last year. If you start them at the same time you'll see the difference between a light, low-powereed R1 Striker on decent tyres and a heavy (620Kg) high-powered (400BHP) Phoenix also on decent tyres. Remember that Llandow is very short so the high-powered cars advantage is reduced considerably. The R1 Striker is very well driven and the Phoenix has me driving (for good or bad).
https://www.youtube.com/watch?v=5mLn1s4_G-c
https://www.youtube.com/watch?v=E1LDEf6TGyo
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