Jump to content
Click here if you are having website access problems ×

420 or 360


rob.mcc45

Recommended Posts

 Hi folks,

I have just joined the club as I’m searching for my first Caterham, after several years of dreaming about it. 

My question is whether the dry sumped 420 is more hassle to live with regarding oil changes etc. compared with the 360 wet sump?

My ideal spec. is:

SV in Ballistic Orange 

Duratec engine 

5 speed box

Carbon dash and front wings

leather seats

15’’ wheels

Thanks Rob. 

Link to comment
Share on other sites

Hi 

wet/dry sump - oil changes are not affected by that but by usage - the more you use your 7 and the more ‘stressful use’ defines your oil changes - usual rules.

there is a benefit Re general ground clearance which some believe can assist them 

360 come with dry sumped  if specc’d so you will find them around

if it is mostly road then 360 is enough but as you use it more you will always want more and get upgrades bothering you if you feel that way

so 420 to 500 to 620  will be your next question anyway

If you can drive the nuts off it already get a 420

if you are new to 7s then 360 is enough for public roads if mostly doing those as you will find yourself enjoying that enough

 

 

 

Link to comment
Share on other sites

Hi Russ,

Thanks for your reply, I understand the potential for upgrading  but I was more concerned about the reliability and just generally oil level checks with a dry sump. I have seen numerous posts about concerns with oil levels and how to check. 

Cheers Rob   

Link to comment
Share on other sites

I don’t see any advantages at all with the 360 other than perhaps cost, which isn’t to much anyway.  

It’s the same engine, so no weight or characteristic advantages. 219/220bhp is still comfortable for the Duratec. 

Oil measuring and changing is easy with the DS and it give a clear advantage on track. 

 

Link to comment
Share on other sites

Rob 

I have owned both, although in 420 form only briefly.  For me it's 420 all day long because the 360 engine character is missing something.   I suspect it's the difference between stock road cams, and upgraded cams.   Somehow all the characteristics people want in their tin top road cars seem out of place in a Caterham.  

I would actual pick the 310 over the 360, assuming I had no intension of upgrading, I think the Sigma cars suit my driving style, or to put that another way, I haven't got used to my duratec car yet.

Link to comment
Share on other sites

  • Area Representative

As written previously no probs with oil changes/consumption with dry sump 420. Just the extra finger scavenge filter on the side to remove & clean.

Have owned a home built dry sump R400D (220 bhp) for six years. Always driven very enthusiastically once warmed up. Oil (5w/50) changed annually along with main filter & removal of finger filter. No problems so far.....

2.0L Duratec in 210/220 bhp form seems unbustable unless the driver totally lacks mechanical sympathy. Wish I had opted earlier but now I have never ever regretted the ££££s.

Definitely the weapon of choice.

Link to comment
Share on other sites

Hi Rob,

I went through the same process, in fact I originally ordered a 360, then changed the order to a 420 to gain the extra ground clearance in the sump.  I was fearful of it catching.   I'm certainly no expert either, but I've done an oil change on my 420 and it's easy, just a few more steps, so I wouldn't let the additional complexity put you off.   I'm not sure about engine characteristics and their differences, the 420 is nice though,  and you get used to the performance, so I'd say go as quick as you can comfortably afford.

I also went 13" with 8" at the rear, I personally prefer the rim design, I feel the 15" looks too modern for the 7 shape.  Additionally, I opted for 13" as the larger tyre side wall should give a more compliant ride, well that's the theory I've no information to support that other than experience changing wheels on other cars.  I also bought the R pack, so wanted to give the ride the best chance on road assuming the R pack suspension to be stiffer than the S.

Having bought and built my first 7 in the last 12 months, I would say the greater or more important question would be the difference between the R and S pack.  This comment is based mainly on my experience of the 420R LSD.  There are far more informed owners on here than me, however in my experience, the current LSD is rather noisy, so you might prefer an open diff.  Maybe other owners could offer additional information here?

Link to comment
Share on other sites

Having owned a 270/310 and a 360, recently upgraded to 210bhp i would also looking at the sigma engined cars, whilst not as powerful or torquey as Duratec’s, aside from trackdays they feel just as fast, and you can keep your right foot planted for longer, Duratec means younhave to back off sooner. Also sigma engined 310 is a sweet motor, similar to old K series, likes to be revved. Duratecs have much more grunt but for road work they arent as sweet. Duratec comes into own on track when power sees you through for passing more powerful cars.

360 and 420 (i upgraded from 180bhp to 210bhp) is noticeable but not that significant, both are VERY fast and more than enough for road work, you will always have to back off. 360 has wet sump and moa oil/water cooler which works well. When i enquired with engine builders about upgrading to dry sump i was told that plenty of people race wet sump cars and they are fine. Having tracked car quite a few times now, i am not worried. Main advantage of dry sump is improved ground clearance but at £2.5k i can live with this.

You mention going for an SV, my 310 was SV but 360 an S3, i am 5’11” and 90kg. For touring and road use would recommend SV just for comfort and convenience, especially if taking a passenger. S3 is a tight fit and good for track days, but unless you are lightly built ultimately uncomfortable. I would recommend leather seats over tillets, way more comfortable ans still supportive.

R or S pack?, main difference is LSD which i suspect most drivers dont need, you really need to cane it for this to start mattering, even with a duratec on 8” rears. Noise wise they bang a bit but nothing bothersome. R doesnt come with weather gear as standard, S does. S also comes with a heater which is a MUST have. Point being S is a lot cheaper and mote practical

Something else to bear in mind is that Caterhams are usually a 2/3rd car and get very lightly used, if you spend big money on overspeccing car you might find yourself deciding to sell it sooner, whereas if it doesnt owe you too much, more likely to keep it longer? 

Dont overlook a nice 310 SV with a 6 speed box, could be the sweet spot of the range? (Think this is what i would go for next time)

 

 

Link to comment
Share on other sites

Wow,

What an amazing and helpful response from everyone from my first ever post on BC. 

I have read them all and will be using the information to help make my decision. As I’m buying used there will always have to be compromises but my main objective will be to get the base car right, other minor things can be changed in time. 

Thanks Jonathan for the offer on the build guide etc. I will be in touch once I have secured a car.

 Thanks again 

Rob  

 

 

Link to comment
Share on other sites

Re the manual, Caterham are currently working on a revised 420 manual, in the Ikea style as it’s known, the type with mostly diagrams.  It was due for release earlier in the year, it reached QA, but has been delayed sadly.  

Link to comment
Share on other sites

Welcome aboard!

I have no experience of the Sigma cars, but I had a 1.8K Supersport-R (160bhp, 6-speed, roller-barrels) for many years, and then moved to an R400 Duratec (both as kits).

The thing I missed most about the K was the sweet and highly revvable engine. So, if the 310 is the same, that would make it a very attractive choice.  As for the R400 (220bhp, roller-barrels, 6-speed, wet sump, and LSD), I just love it for its sheer poke and all-round capability.  Both my cars were S3, a tight fit for my 90+kg and 1.79m, but as I hardly ever carry passengers, that's no problem.  Besides, I really like the original 7 dimensions.  And for me, leather seats and a heater every time.

My R400D is probably a mix of the current 420R and 420S specs.  I do a lot of touring, so wanted a windscreen.  Some owners regard the 6-speed as overkill on a Duratec, but I find it utterly delightful.  Sure, it means a buzzy motor on motorways, but it's perfect for the twisty bits.

Re manuals, you probably know that you can download the 2019 IKEA-style version 1.2 (for Sigmas) and the older (2015) text-style Duratec version from CC's website.  And JK is the go-to source of documentation for earlier cars.

Hope you find your ideal car soon...

JV

Link to comment
Share on other sites

Have bought one kit had it built for me but did not keep it long present car is sigma 150: which I find enough for road use ,,and car is a SV to me is a must for touring , looked at buying a new kit five years ago went to caterham midlands

Had a test drive in a couple of dif cars then had a ride in the car I bought ,,thought can save few thousand pounds get a nice motor have just driven and drive away and use so bought it  , unless you want to build your own think about second hand one with low miles nut make it an SV 

derek

Link to comment
Share on other sites

I’ve had a 125 Sigma and currently a 420. 

The extra ground clearance of the dry sump on the 420 makes a big difference, I was forever clonking the sump on the Sigma. 

Personally, it took about 18 months of road use to get to the point of needing more power in the 125 and the cost of upgrading was going to be huge; hence why I went 420. 

13” wheels “look right” for Caterhams, the 15” Orcas are too “modern”. 

Yu may also want to consider the “upgraded” 4 piston brakes if you go down the 420 route; I’ve found them to be very good. 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...