New 420

[edo]

Bit grumpy at cold, will stall if I don't give it a little bit of revs for a while.. TADTS?

[Beagler]

Mines same. Guy that delivered said they are all like that.

[edo]

ok, good to know thanks

 

[7 wonders of the world]

Unacceptable...... that they are being sold like that, even worse if they are delivery new factory built cars to customer in that condition.  

 

[Beagler]

After a minute mine runs and idles fine and goes like stink so no complaints.

[7Up]

mine the same, till i got a decent map and fuel pressure reg.

[7oaks]

I have a 2016 420R, has never stalled, idles fine when cold.  I bought second-hand, so maybe its a new engine thing and just needs a few miles on it?

[edo]

Will keep an eye on it / mention it at running in service. Its absoloutely fine after a couple of minutes. Chap delivering seemed to think that all the dry sumped cars were like it. 

[Mrb00ns]

Give it a chance for a run in, but you might want to think about taking it to someone who knows what they are doing and look at a remap. 

[ScottR400D]

Just needs setting up properly. 

It's not true to say they all do that but many do. They don't have to though. 

[Beagler]

If I press the starter without any throttle as per manual it is ok. Pressing the throttle on startup is my bad habit.

[Grant_7]

My old Sigma Supersport was a nightmare; idled from cold for about 20 seconds, before being all over the place (including stalling) until it had done a mile or two.

My current 420R RBTB  was better (no stalling), but was a bit 'grumpy' until warm.

However earlier this year I took my 420R to Northampton Motorsport and had it mapped. The difference is night and day! It now fires up immediately and settles to a perfectly stable idle whether cold or hot. Driveability is massively improved and it's made the car so more better to drive.

[Nigel B]

My 2017 420R was exactly the same. It had a tendency to cut out for the first few minutes when started from cold, but ran fine once there was a bit of heat in it. 

I had a set of roller barrel throttle bodies fitted by Luke Stevens, along with a remap by Steve Greenald & the problem has gone, it now runs perfectly from cold.

Admittedly, that's not the cheapest solution, but it is highly recommended! 

Gratuitous photo...

[ScottR400D]

Looks good Nigel, and just about what I did! Luke flat floored my car a couple of months back and I had a chat with Steve who was there doing yet another one! 

Hope you're well?

 

[Geoff Brown]

Grant_7 #12 - So Northampton Motorsport can unlock the ECU ?

[edo]

Thanks Nigel, what sort of money we talking? Having just spunked £45k on the car I'm not feeling the love for having to spend money getting it running properly!

Can someone point me at this flat floor business everyone keeps talking about?

[ChrisC]

So as others have said, it's not TADS, but a setup thing.  Its normally combined with hesitation.  You don't need to spend on RBTB to get the car running properly, you need to spend on RBTB for performance, noise and drama.

[ScottR400D]

#16 

Flat floor is a term that refers to having your car set up so the ride height, corner weights, toe, caster and camber are optimised. 

For obvious reasons it needs to be done on a flat surface, hence the terminology. 

There are several race teams/service operations with experience of the 7 who should be able to do a good job 

[edo]

thanks. I stupidly assumed a factory car might turn up already setup!

[Nigel B]

Ed, I've sent you a PM regarding the cost of the RBTBs.
 

Chris C is right though, roller barrels are not necessary to make the car run correctly, they'd be a bit of a 'sledgehammer to crack a nut' solution! They are a nice addition though, if you like your Sevens rorty!
 

I'm doing very well thanks, Peter. The Caterham is tucked away for the winter now though. I hope you're pleased with your new set up.

[ScottR400D]

#19 Maybe, maybe not!!

[GulfSeven]

My new 310R needed its TPS adjusting. I put the tendency to stall down to me not being used to the lightweight flywheel initially. Drivability is a lot better since it's been calibrated!

[aerobod - near CYYC]

The overall problem seems to be variation of mixture needs between cars for low speed running, especially when the engine is cold. The generic Caterham map doesn't take into account any variation, so with many cars will be a bit rich or lean, leading to hesitation (lean) stumbling (rich) or hunting idle speed.

Once warmed up the engine is less sensitive to the variations. I believe a lot has to do with the relatively high lift cams and fair overlap compared with most road cars. Custom mapping will optimize for a specific car and a bit of adjustment on the TPS and idle screw may help, too.

In my case I just went for an unlocked ECU and a new map, as my R400D is used at altitude and there is no compensation for that in the stock Caterham MAP based map, I also converted to AlphaN mapping and ditched the MAP sensor at the same time, although I'm still on a plenum system, not RTBs.

[ScottR400D]

#20 Quite happy with the way it all is now, Nigel. At least I think I am! 

We had the car out at Snet a couple of days after it was set up. It seemed OK but the day just got wetter and wetter. It was soon too wet for me though my son carrIed on for a few sessions with me as a passenger. He pronounced it as much better than before and thought the LSD was working well too. By the way he had it drifting about the flooded track it seems to all be working well enough!! 

Anyway by the time I'd got it all dry and clean I only got out for a couple of local runs pre hibernation! All seemed well though but some longer runs in the spring will be the proof. 

Happy Christmas! 

[edo]

Useful thanks. Interestingly where I live is quite high at over 600ft, I wonder if this contributes too?