125 or 175

[Alan Reeves]

I am buying a new SV and have been procrastinating over 125 or 175BHP, views are welcomed on pros and cons. I do not want 150 as to revvy and I prefer torque. But the 175 is serious money over 125.

[CageyH]

What ever you get - it won't be enough.

I started with 135, and now how around 200. It was expensive upgrading.

 

175 seems like the best bet to me! It will be cheaper in the long run...

 

Only dead fish go with the flow....!

[MADMALC]

It appears that the 125 and 150 have the same max torque and there is only 250rpm difference in revs between them. The 175 maxes out at 7000rpm, and 6900rpm for the 150 is in the same area.

So if you have the money go 175, if you need to save a little go 150. You may well be dissapointed in the long run with 125.

You need as many horses as you can afford, you do not have to use them all the time but they are there when you need them.

 

S7MAD

[Sigmamark]

The only place where I have ever found 125 to be better than 175 was with BSA Bantams, so sell a Kidney and go for the 175 (as a minimum)

[Racing Snake]

175 for sure

You will soon be longing for more go if you go the 125 route and it will cost your more to upgrade

I know just upgrading to over 300 😬

 

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Mad Hatter Racing - Feel The Duralight R Torque 😬 Carl @ Penn 7's Caution - May Contain Nuts !

[DJ.]

It all depends on what you want. I suspect you already know the answer and are going to go for the 175.

 

It would be a shame to end up selling or upgrading after a short time. I assume you've driven cars with both engines.

 

Are you plannig to upgrade the wheels and tyres? I think 185s are fine for adjustabilty with the small engine, but with duratec torque, I think you'll be wanting stickier tyres.

 

I've ordered a 125, but I've owned a Lotus Elan sprint with a standard engine on 155 tyres and never wanted to upgrade it. I'm just the sort of person who enjoys exploring the limits of a car however slow it is. If you crave the excitement of very rapid acceleration you'll want the 2 litre :)

 

 

[rswestling]

150 is just right in a Caterham, especially if you plan to use it mostly on the road. Revvy? Not really, it feels absolutely spot on. If you want torque, maybe a turbo diesel would be better.

 

The better question is why get an SV? They're so big!

 

-robert

 

 

 

[sevenmad]

I had my 125 on the road for about 4 months. I'm just beginning to think more power would be good, and I may well upgrade to 150. My car is an S3.

 

If I had the heavier SV I'm sure I'd want more power! I'd go for the 175. As others have already said, this gives an easier upgrade path if you want to go even further. it's better to stomp up more now than even more later.

[Racing Snake]

150 just right in a Caterham

 

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Mad Hatter Racing - Feel The Duralight R Torque 😬 Carl @ Penn 7's Caution - May Contain Nuts !

[ALEVS7]

😬

 

Al Evs.

 

The Ultimate driving machine isn't German!!!....here

[MartinH]

Of course everyone is going to try and sell you the choice they made and I will be no different! Go for 175!!!

 

175 means a 2.0 Duratec and this has incremental upgrades to over 250BHP

 

Squeezing more than 150 out of the Sigma engine seems to me a much harder job - although the tuners will no doubt perfect an approach at some point to get a bit more.

 

I hired a 150 Sigma from CC two years ago, which was a lot of fun, but once I had a test drive in the R300 (Duratec 175) well...I had to sell the kidney as Sigmamark said!

 

Best thing you can do is try both.

 

Good luck on your journey.

 

Cheers,

 

Martin

 

Duratec R300 SV Build Pics

[mattobrien]

Just in case it's not obvious, get the 2l duratec. As has been said it is at the bottom end of the engines capabilities and therefore there is a path to upgrades. Believe me the need for more power will happen and a durance is a great place to start.

 

Enjoy making the decision and see if you can get some more test drives to help you decide

 

Matt

 

 

[Rattie]

If you can afford the 2.0l do it. If you want torque, do it. Otherwise you will kick yourself later.

 

Martyn

^_R300GRR

[Tangerine Dream]

175. The 2.0 Duratec is exceptionally torquey in my R400 SV. I imagine a Roadsport 175 will be similar but just not have quite such a mental bit in the last 2000rpm.

 

Cheaper to get it now than upgrade later and the Duratec is a good engine.

 

==================================

R400SV in orange - so far unmodified!

[TobyCoulson]

I have a 150 and and I wish the 175 option was available when I bought it.

 

There is motor racing and then there is F1

[Mick Day]

Good morning Alan & welcome to the madness that is Caterham ownership!

 

As you can see there are more views on this forum than you can shake an engine stand at!

 

Most owners I know (including myself) have started out at the lower end of engine development & progressed upwards in search of more fun. I haven't met anyone yet who has regretted this but many regret not buying the performance in the 1st place.

 

If I was doing this again I would probably buy a starter kit & source the engine myself.

 

Food for thought??.............

 

Plenty of suppliers out there & plenty of technical help here.

[The Pikey]

 

 

Hi Alan

 

Without any doubt I'd be going for the Duratec 175 over the Sigma 125. As others have said, whatever you buy it won't be enough and when this happens the 175 is easy to upgrade at a reasonable cost to 220 ish bhp and well beyond if you shell out some serious cash.

 

Jason

 

 

 

 

 

[John Cockburn]

Hi Alan,

 

I have a 150 SV which I completed in May 2008 and I think the engine and 5 speed gearbox make for a very good combination. I have driven 9500 fun miles and never really found the need for more power, however had the 175 been available when I purchased mine i would have gone for that option.

 

Cheers John

[Alan Reeves]

Well I cant complain at the lack of interest , in fact Im impressed....more than 50 hits and 17 replies in 12 hours...you guys need to get a life, and some of you jobs....the Edinburgh fringe is always available.

 

Thanks all and I do believe I know the answer but...£6k additional seems extremely high no matter how imaginative they are...perhaps the forum would like to now tell me why ?

 

 

[Mick Day]

...perhaps the forum would like to now tell me why ?

I suppose because we can........................ 😬

 

When I built my car in 1994 I thought with the light weight that 100 BHP would be more than enough, however I forgot to factor in the barn-door-style aerodynamics. That & taking an interest in track days meant a development curve that for me has now peaked at 227.

 

It's also been fun & I've met a lot of nice people along the way.

 

Edited by - Mick Day on 6 Aug 2010 11:54:43

[Rattie]

Alan,

 

It's probably a function what the market will bear and an amortisation of what they've put into developing the setup, plus profit. If it bothers you, get a kit sans engine and DIY. Ammo can do you one for around 2K. Alternatively, have a bash at beating CC down on the price. Good luck 😬

 

BTW, by my maths £5100 is less than £6000. See, we just saved you £900!

 

Martyn

^_R300GRR

[Mick Day]

If it bothers you, get a kit sans engine and DIY.

That's what I've told him, more than once.

[Tangerine Dream]

Is the extra £6K just for the different engine?

 

I was going to get an R300 but I absolutely wanted dry sump and LSD and rather fancied shift lights. Once I added that lot to the R300, it was only £1600 less than the R400 which has all 3 items as standard.

 

I am wondering if it is a similar thing with your 125/175 dilemma or if all the money really is on the engine alone.

 

==================================

R400SV in orange - so far unmodified!

[DougBaker]

Whatever you buy you will have a great time. I have a 1.6K SV and have done multiple track days in it as well as European trips. Could it do with more power, of course, is it still absolutely great fun the drive of course. You don't need a powerful engine to go round corners quickly on track.

 

If I had purchased a larger engine and been unable to afford to track the car and take it abroad it would have been a really bad decision. Seven years into ownership I still have not needed to upgrade the power, when I get round to it I will fit Brooklands screens to improve the aerodynamics. Although I would have to admit to not having driven the car enough the last few years due to young children.

 

2003 Roadsport SV 1.6K 5 speed.

[The Pikey]

6k more for the 175 over the 125!!

 

So can someone justifie the difference in price? A Duratec 175 is 1500 quid, I guess it's got a Raceline wet sump has it? If so thats about 400 quid. 500 quid for caterhams plenum and TB. So thats £2400 and then you still have your engine to sell to pay for the stuff I forgot about..

 

Serious pricing issue here

 

Jason