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performance figures
Lotusmark2 - 29/1/05 at 08:25 AM

Hi all,
Just a quick question.
What sort of performance will you be looking at from a locost with a standard 1600 x-flow?
Cheers
Mark


smart51 - 29/1/05 at 11:51 AM

westfiled quote their 155BHP 1.8 Zetec car at 5.4s

caterham quote their 105Bhp K series car at 6.5s

by using a bit of maths, I guess that a 1.8 pinto engined car will take about 8s depending on weight mainly

a 1.7 crossflow? how powerful is it? it might make 60 in less than 10s.


JoelP - 29/1/05 at 01:00 PM

i would be shocked if a 1.7 xflow car took 10 seconds to 60... thats terrible! surely it must produce at least 80bhp? hence nearly 150 per tonne, which (forgetting gearing and grip) might be 8 seconds.


Lotusmark2 - 29/1/05 at 01:13 PM

I must admit I thought that seemed very slow (have a deisel estate on the drive which is much faster than that!)
So If I want sub 7 seconds to 60 am I limited to the engines with ECU's (hate damb computers in my cars)


britishtrident - 29/1/05 at 01:17 PM

Just look up the 0-60 times for an S4 Seven or early Caterham n --- 7 point something isr --- not exactly hanging about.


britishtrident - 29/1/05 at 01:22 PM

quote:
Originally posted by Lotusmark2
I must admit I thought that seemed very slow (have a deisel estate on the drive which is much faster than that!)
So If I want sub 7 seconds to 60 am I limited to the engines with ECU's (hate damb computers in my cars)


No you just bolt a set of twin 40s or 45s, a slightly hotter cam and off you go or better still see Dave Baker Puma racing website in links section for more on xflo mods.

Another alternative is the 1.6 cvh using and old fashioned dizzie --again see the Puma site for info.


Stu16v - 29/1/05 at 01:39 PM

quote:
Originally posted by Lotusmark2
I must admit I thought that seemed very slow (have a deisel estate on the drive which is much faster than that!)
So If I want sub 7 seconds to 60 am I limited to the engines with ECU's (hate damb computers in my cars)


The 0-60 thing is not a very good indication of how fast a car can get moving from standstill - they are quite often merely pub bragging figures, in much the same way as quoted BHP figures. I had a Astra GTE 16v, with a quoted 0-60 figure of around 7 secs IIRC. However, my Westfield was powered with a totally standard 1600 GT xflow (OK, it had a nice exhaust manifold, and a K+N fitted on the standard twin choke carb), and it would totally blitz the GTE from a standing start. The car may take longer to get to sixty, but it has covered a lot more distance in doing so, if you see what I mean. And that is what counts, does it not?

[Edited on 29/1/05 by Stu16v]


Dale - 29/1/05 at 11:21 PM

It relates alot to the traction level of this car on takeoff- small wheels and low weight and alot of spinning. The rear arms to the axle could be set for better traction on a start but will probably hurt your handling.
Bigger higher profile tires will help on take off but hurt in handling after- a trade off I guess. I am going with 15x8 wheels and probably 225-60s or 245-50s depending on pricing mostly.


Power to weight and bhp/tonne can be hard to judge as well.
My car is going to be heavy for a locost-- its bigger longer and more thirties style-- A very heavy est. with me in it of 1850lb- should come in at 100lbs lighter I hope( I am 245lbs) I have figured that I will have a bhp/tonne of around 240 with the engine stock and plan to build the engine up a bit after the car is on the road and I am used to it to bump the hp from around 200-225 to the 300hp range (which is midlevel build up as I dont want to blow the thing up too much or make it peaky on the powerband) That would put me in the 360 bhp/tonne range. If calculated with out my lardy self in there the numbers are close to 280, and 420 bhp/tonne and this is with a car that weighs in at 3-400 lbs heavier than most of yours. I have been aiming at under 5 seconds 0-60mph and It should be close at the 200 hp range. An extra 100hp after that should get me close to under 4 but who knows.

Dale


britishtrident - 30/1/05 at 01:42 PM

quote:
Originally posted by Stu16v
quote:
Originally posted by Lotusmark2
I must admit I thought that seemed very slow (have a deisel estate on the drive which is much faster than that!)
So If I want sub 7 seconds to 60 am I limited to the engines with ECU's (hate damb computers in my cars)


The 0-60 thing is not a very good indication of how fast a car can get moving from standstill - they are quite often merely pub bragging figures, in much the same way as quoted BHP figures. I had a Astra GTE 16v, with a quoted 0-60 figure of around 7 secs IIRC. However, my Westfield was powered with a totally standard 1600 GT xflow (OK, it had a nice exhaust manifold, and a K+N fitted on the standard twin choke carb), and it would totally blitz the GTE from a standing start. The car may take longer to get to sixty, but it has covered a lot more distance in doing so, if you see what I mean. And that is what counts, does it not?
[Edited on 29/1/05 by Stu16v]


Traction is the killer on fwd cars as the weight is transfered on to the rear wheels, most quoted 0-60 times for fwd cars are done on high mu surfaces.


David Jenkins - 30/1/05 at 02:54 PM

I've found that the standing-start time is not what these cars are all about anyway - they're certainly quick doing that thing, but what's really impressed me has been the mid-range acceleration. For example, I've been doing 70mph in 5th on the local main road and booted it to overtake - and been REALLY impressed with the way it's just picked up and gone. In my day car I'd have to have dropped at least one gear and I still wouldn't have accelerated as fast. This is with a 1660 x-flow with a very modest tune-up.
The nimbleness, the ability to whizz through corners and hammer away, is the appeal of my car as far as I'm concerned.

David


hurf69 - 30/1/05 at 05:12 PM

i have a luego velocity 1800 zetec on omex management system quoted 135bhp at wheels on dyno and did a 0-60 time at my local track of 5.02 secs which aint bad. i always wanted a 4s car but this one will do i can beat my mate to about 90 on a stright road and he was in a gt3 so i am very happy.


britishtrident - 30/1/05 at 07:31 PM

I found the 0-60 times for the 1960s Lotus Seven S3 7.7 seconds for an 84 bhp 1600GT and 6.2 seconds with the Elan 125bhp 1558 cc SSE spec (as fitted to the Elan Plus2S) Twincam --- I would take times and BHP figures with a pinch of salt as Lotus were well known for tweaking pres demo cars and Lotus Twincam BHP figures were always higher than actual.


britishtrident - 30/1/05 at 07:38 PM

quote:
Originally posted by hurf69
i have a luego velocity 1800 zetec on omex management system quoted 135bhp at wheels on dyno and did a 0-60 time at my local track of 5.02 secs which aint bad. i always wanted a 4s car but this one will do i can beat my mate to about 90 on a stright road and he was in a gt3 so i am very happy.


The fits almost exactly with Caterhams Cosworth BDG engined S3 which claimed 150bhp at the flywheel


hurf69 - 30/1/05 at 08:30 PM

cool i want to get more out of it as well any ideas anyone


Lotusmark2 - 30/1/05 at 08:35 PM

ok so does anyone have any idea on a 400kg car with 105 bhp (fly wheel)?
What sort of performance do you guys think?


hurf69 - 30/1/05 at 08:46 PM

135hp on 515 kg is 5s ish so i would assume 105 on 400 (thats very light) should be as quick . use a bike engine if you can


Lotusmark2 - 30/1/05 at 08:49 PM

Sticking with an A+ (with a bit of tweeking) but may change to bike if I ever get to the limitsof the engine I will be building.
(350-400kg single seater not locost)


hurf69 - 30/1/05 at 08:53 PM

phew i thoght you were buiding with tishue paper. how much performance do you want


Lotusmark2 - 30/1/05 at 08:57 PM

sub 6 seconds is fine for now.


hurf69 - 30/1/05 at 09:00 PM

cant see why not at all , you will have 260-280 bhp per tonne at least


britishtrident - 30/1/05 at 10:36 PM

quote:
Originally posted by hurf69
135hp on 515 kg is 5s ish so i would assume 105 on 400 (thats very light) should be as quick . use a bike engine if you can


That 135 is at the wheels the 105 is at the flywheel a lot less at the wheels especially on fwd due to drop gear losses 105 would equate to low 70s at the wheels.


tks - 31/1/05 at 11:15 PM

110BHP @ 450Kgs do??

its bike engine if it matters....

i'm also a unther 5sec wannabee but i think i don't get them with this engine but hey thats the reason i'm a wannabee..

TKS


alfasudsprint - 5/2/05 at 06:57 PM

whenever i read about 0-60 being irrelevant i agree, but its hard to ignore the numbers too!
FWIW 1.6 k series in a Cat., 115bhp, 544kg takes 6.2 seconds.
I have 140bhp and around 590kgs i think (based on a VX Cat 2.0 590kg, my lump being a similar heavy lump). Am hoping for around 6 secs or less.
numbers from The Magnificent Seven by Chris Rees, which i refer to every week for ideas and even angles of things from the excellent photos. Recommended.
Tim


EddThompson - 6/2/05 at 09:56 PM

first post so dont bite.

I like 0-60 figures, and 1/4 mile, pub boast factor aside (which is nice) the give you an indication of straight line speed.

Im very temped by a locost type car at the minute, but to make it worth while it will have to quicker than my last car, and mr2 turbo with 230bhp, 0-60 6 seconds and a 1/4 mile of 14.7 (when i had a duff clutch) and its not exactly a poor handler.

but at 1400 kilos its not the lightest is it?

so i reckon a 700 kilo car (with me in it) and say 150+ bhp might do it

pity i cant just take the 3gste engine out and fit it in an sylva mojo or something.


edd


JoelP - 6/2/05 at 10:16 PM

hi mate.

700kgs is an easy target to reach, gives you some leeway for creature comforts! or a heavy engine...

lightest i remember someone saying was sub 500kgs, maybe significantly under if memory serves.


EddThompson - 6/2/05 at 10:28 PM

ahhaaaaa, but im 19 odd stone, emm 130kilos?? so a 500 kilo car with me in is 630 im going to have to weight the passenger side for even balance lol.

Im not even sure ill fit in a locost, need to sit in one or two, i can drive a lot of small cars as im just quite tall (6'5".

Its a pain when you start to afect the performance of you car isnt it,

edd


JoelP - 6/2/05 at 10:35 PM

damn right...! im 6'2 but a skinny git, probs 13 stone.


Dale - 6/2/05 at 11:51 PM

I know mine will be going the strip a few times-- and I will pissed I am am running anything over 13's hopefullly get it to the low 12's. The engine I am using was taking a car more than a 1000 lbs more than I will end up with in the 13's.
Dale


twybrow - 15/8/06 at 03:48 PM

I was talking to a researcher working for Caterham and i was astounded by the lightest (and most expensive car) Caterham have made... Any guesses at cost....? Try £82,000! And weight with half a tank but no driver of this one off special was a mere 380kg! Needless to say not just the fancy looking bits were carbon!


Ham - 16/8/06 at 09:14 AM

FWIW, standard x-flow 1600 - 82 bhp
My spec - 1660,275 deg cam,flowed,big valve head,lightened and balanced, 38 DGAS - 113 bhp, car weight - 570kg
BHP/Ton - 198, gets to 100km/h in under 6