Please Review These Build Specs: 420R

[rider]

Hey everyone. I'm one step closer to joining the Looney Club! Just about to commit myself to a build slot. This has been many years in the making! Multiple attempts were made! It's about to happen finally!

 

I'm planning to target August build; so, the specs freeze window is just about now. Wanted to get some feedback from you guys on the specs. 

Will make a separate thread for custom work such as fixing the fuel gauge, mirrors, 3rd brake light ......

 

So, what do you guys think? Thanks. 

420R
Exocet Red
Large Chassis
Front - Ventilated discs with quad piston calipers
13" Apollo wheels, 6" Front, 8" rear w/Toyo 888R tires, silver

              Any concern on availability of tire options for 13s (as opposed to 15s) long term?
Track day roll cage
Painted roll cage, Polar White
Full windscreen hood & side screens (in lieu of aeroscreen)
Side screen armrests
Fully carpeted interior
Seats - Black leather
Momo suede steering wheel ,fixed. 280mm substituted instead of 260mm
Heater
Sequential shift lights
Map pocket
High intensity lights with LED side lights, running lights
Clear lens pack
Painted 7 grille, Polar White
Carbon side and rear panels(standard on 620 models)
620 Style Dash/Switchgear
620 Style Nosecone
Painted headlight bowls
Brakes - Front – ventilated discs with quad piston calipers
Standard Seat Belts, Inertia Reel 3-point belts."
Roller barrel ITBs and carbon fiber air box

 

[Vovchandr]

Look pretty good. 

 

13s are a better option in most ways but we are at the beckons of the industry. Nobody knows what long term holds and tires isn't something you can stash forever. 

 

If you consider ever going aero I would prep from start. It's a major difference of experience and I never use windshield until I have to. 

[CBuff]

Second @Vovchandr on aero. It wasn’t something that I thought about doing. But installing the bracket after the fact can be a pain (I hear).  I added it just so that the bracket would be installed.  Now I use the aero at the track exclusively. 
 

sounds like you are going to be road only (vs road and track) with the 3 pt belts.  If you haven’t gone out on the track it’s worth a try.  If you think you might go in the future you would likely need 6 pt belts (possibly dated per track requirements). 
 

I changed the mirrors to dpr before it even got delivered.

https://parts.dpr-motorsport.com/contents/en-uk/d24

 

 Added fuel gauge mod.  

And added 3rd brake lights from @das76

 

 

I also got a tunnel bag and 1/2 hood from side bits. Haven’t used the full hood ever. But the 1/2 has come in super handy. 

[rider]

Thanks @Vovchandr. If 13 tires become unavailable, we can switch to 15s. So, not an issue I suppose. 

 

From safety standpoint, I don't think I will consider Aero Screens. Additionally, wind buffeting and wind noise are big issues as well. These days I use earplugs any time top is down. Decades of abuse (motorcycles and open-tops) might have a payback that I yet to face; it may be coming....... But, I can see how different the experience will be with Aero!

 

 

Edited June 26 by rider

[wdb]

Congratulations on your imminent arrival! I can't really help with modern specs as my car is a throwback, but I can discuss more general topics.

 

Wind buffeting is a pretty large part of the Caterham experience even with a windshield. The novel combination of windshield and rear fender combine to slam air at the occupants' outward facing ears. I'm considering removing the windshield on my car to see what it would be like with a brooklands screen. 

[CarlB]

I actually like driving with the aro screen better than the windshield. With the windshield the air blows around the windshield and in your face.

[Croc]

So what are you?  Track or Road?  You seem to have put a foot in each and made a confusing spec. 

 

First, I would never have a cage for road.  You must always wear a helmet if you have a cage.  The consequences of clouting your head are major.  Do you really want to wear a helmet all the time on the road?

 

Second, three point belts and a cage?  Thats just going to make the impact off the first point worse. 

 

Third, does the windscreen fit that track day cage?  I am just looking at my UK 420R photos and I think it will conflict with the mounting points of the windscreen.  You should probably confirm you are ok with your Caterham dealer.  Sidescreens will work with that cage if the windscreen can.  

 

Fourth, I do not see it but add an LSD.  

 

 

A couple of other things:

1) what suspension set up are you spec'ing?  The standard R version?

 

2) The ITB upgrade to the standard 420R plenum has caught people out with the ECU upgrade.  It always seems to need to go back to the factory to get reflashed - check with the dealer to make sure it is done prior to arriving in your hot little hands.    Its an essential upgrade once sorted - sensational induction noises.  

 

 

 

 

[rider]

50 minutes ago, CBuff said:

...........Now I use the aero at the track exclusively. 
 

sounds like you are going to be road only (vs road and track) with the 3 pt belts.  If you haven’t gone out on the track it’s worth a try.  If you think you might go in the future you would likely need 6 pt belts (possibly dated per track requirements). 
 

I changed the mirrors to dpr before it even got delivered.

........

 

 Added fuel gauge mod.  

 

And added 3rd brake lights from @das76

 

I also got a tunnel bag and 1/2 hood from side bits. Haven’t used the full hood ever. But the 1/2 has come in super handy. 

 

 

These are great; thanks @CBuff. Appreciate it. 

 

At the track, you would be using a helmet; so, I can see how Aero would work. I do agree that it would be cool to drive with Aero.....!

 

Yes, I won't be tracking. Never have. My problem is, I would get carried away easily!! However, if I do decide to track, how hard is it to install 6-point?

 

The mirrors are a winner. Will order them and have Rick (Kampena) install during the build, along with other mods you shared. Appreciate it. And, yes, will get the top and bag (along with a few other stuff) from Soft Bits.

 

Your help already crossed off three items from the list......  

 

[11Budlite]

23 minutes ago, Croc said:

Fourth, I do not see it but add an LSD.  

The 420R should come standard with LSD.

Edited June 26 by 11Budlite

[rider]

59 minutes ago, wdb said:

.......... The novel combination of windshield and rear fender combine to slam air at the occupants' outward facing ears. I'm considering removing the windshield on my car to see what it would be like with a brooklands screen. 

 

 

47 minutes ago, CarlB said:

I actually like driving with the aro screen better than the windshield. With the windshield the air blows around the windshield and in your face.

 

@wdb, @CarlB: Thanks. I read through that thread. From safety standpoint, I definitely can't do anything other than full windscreen. Wearing helmet is reserved for motorcycles..... Earplugs, of course, are mandatory!

 

The video reviews I have seen, cars with full windscreen and side screens seemed pretty reasonable. Of course, I haven't experienced it; you have. So, I'm bit baffled.....

 

 

47 minutes ago, Croc said:

So what are you?  Track or Road?  You seem to have put a foot in each and made a confusing spec. 

 

First, I would never have a cage for road.  You must always wear a helmet if you have a cage.  The consequences of clouting your head are major.  Do you really want to wear a helmet all the time on the road?

 

Second, three point belts and a cage?  Thats just going to make the impact off the first point worse. 

 

Third, does the windscreen fit that track day cage?  I am just looking at my UK 420R photos and I think it will conflict with the mounting points of the windscreen.  You should probably confirm you are ok with your Caterham dealer.  Sidescreens will work with that cage if the windscreen can.  

 

Fourth, I do not see it but add an LSD.  

 

A couple of other things:

1) what suspension set up are you spec'ing?  The standard R version?

 

2) The ITB upgrade to the standard 420R plenum has caught people out with the ECU upgrade.  It always seems to need to go back to the factory to get reflashed - check with the dealer to make sure it is done prior to arriving in your hot little hands.    Its an essential upgrade once sorted - sensational induction noises.  

 

 

36 minutes ago, 11Budlite said:

The 420R should come standard with LSD.

 

Thanks @Croc. All great points and questions. 

 

- This is strictly road car. I tried to spec for spirited experience without wandering into track territory. 

- Why Trackday Roll Cage then? 

   - It adds rigidity.

   - Rollover protection.

   - Helps to hold onto a solid frame when getting in/out. So, easier with ingress/egress. However, I have not tried this. So, I'm going with reviews. 

 

However, I never read/heard anyone mentioning you could hit the cage! But then, I have only seen pictures extremely few Sevens with Trackday Roll Cage. No, I won't be wearing a helmet. So, you think I could hit my head onto cage from road bumps? From the picture, there seems to be plenty of clearance. 

 

Yes, windscreen works with Trackday Roll Cage:

 

 

 

LSD: 

@11Budlite is correct; R comes with LSD.

 

Suspension: 

Standard R-spec ('Sport').

 

ITB:

Good call on ECU re-flash. Will check with Rick. I have no doubt; he already knows it. 

 

So, as you see, the only track-related component is the roll cage. Otherwise, road-focused specs, I think! Thanks again; appreciate the questions and pointers.

 

 

 

 

 

 

 

 

[panamericano]

Croc's comment about hitting a roll cage is vital.  The team once saw fit to remove the padding from my cage..Rally.. Off the mountain, rolled 3 or 4 times (my count vs. Navigator's).  Hit cage with helmet on the first roll over and cracked it enough to come over my face.  Sucked head into shoulders and didn't hit it again, but scary.  Amazing how much one can stretch.  I always wore belts TIGHT, enough to have shoulder bruises after a few days' rally.  Cage requires helmet and padding.  

[CBuff]

I had the dpr mirrors mounted on the lower windshield frame.  Just make sure the factory doesn’t drill into your doors for the factory mirrors. I purchased some of the mounting hardware from dpr but don’t know what can be reused from the factory stuff. 
 

 

here is the half hood. I got easy in zips but don’t really use them to be honest. May experiment with opening then and driving like that for a bit if an open top half hood.  
 

 

I also mounted my central mirror a bit unconventionally down low on the windscreen.  I actually really like it there. Your view is below the X in the cross bar and it doesn’t block forward view.  Can be moved if needed. 
 

the brake light kit installed. They are low enough down so they don’t get blocked by the half hood. 

 

6 point retrofit isn’t that big of a deal. Just have to figure out sub straps with the leather seats. Some folks just sit on the sub straps and they go thru the back of the seats.  I had my squabs cut 

[demoray]

If you buy the eckels door mounts from DPR, you can use thr hardware on either the door or the windscreen.

 

When I'm going somewhere with the doors, I use the door mount.   When I am going somewhere without the doors, I mount them to the windscreen.

 

[rider]

3 hours ago, panamericano said:

Croc's comment about hitting a roll cage is vital.  .......... Cage requires helmet and padding.  

 

Scary indeed, @panamericano; thanks for sharing. Was that cage 'Sport Roll Cage' shown below?

 

As you know, it would be impossible to think through how a specific roll cage works in an unknown scenario/variable. 

 

 

3 hours ago, CBuff said:

........ Just make sure the factory doesn’t drill into your doors for the factory mirrors. ............
 

here is the half hood. ........... May experiment with opening then and driving like that for a bit if an open top half hood.  
 

I also mounted my central mirror a bit unconventionally down low on the windscreen.  ...............
 

the brake light kit installed. They are low enough down so they don’t get blocked by the half hood. 

 

6 point retrofit isn’t that big of a deal. ...........

 

 

Awesome; really appreciate your help, @CBuff. 

 

Mirrors: Aren't they mounted on the doors, from the factory? Then why would they drill holes on the windscreen frame? With DPR mirrors mounted, guessing you don't have an issue with the doors opening and closing?

 

As for the center, inside mirror, it could go on the roll cage, as DPR shown on their page. 

 

Half-Hood: Under what scenarios would be driving with top zipped closed half-way? As for me, unless it's raining, the top stays off! If it's raining (or forecast to rain), Seven will stay home.......

 

Brake Light: Looks interesting. Will think this through.

 

6-Point: Good to know it's not hard to retrofit. I don't expect to track though; have a few other serious interests to suck up whatever little time I have......

 

Questions on heat: Does your pedal box or transmission tunnel (or, both) get hot? If they do, what mitigations you have taken or considering? 

 

Thanks again. Nice green by the way! What is it called?

 

 

1 hour ago, demoray said:

If you buy the eckels door mounts from DPR, you can use thr hardware on either the door or the windscreen.

.....

 

Thanks @demoray. I plan to mount them on the windscreen frame. And, I don't expect to drive without doors.

 

 

 

Edited June 27 by rider

[Croc]

11 hours ago, panamericano said:

Cage requires helmet and padding.  

 

And harness not three points

[Croc]

12 hours ago, rider said:

Yes, windscreen works with Trackday Roll Cage:

 

 

 

 

 

Well that is interesting.  I bought a track day cage from Caterham for my 420R 18 months ago and it does not look like that on the front bars. 

 

This is a family member in my UK 420R  at Spa last October (finally hitting the apex at La Source too!)

 

 

 

Notice how the front mount points and bars that slope rearwards will conflict with windscreen in that version.  Hopefully they have changed the design to be like the image render from the purchase website.  

 

For estimating head clearance, in my car, Lucas is 5'8" and there are no lowered floors in that SV chassis.  

[CBuff]

8 hours ago, rider said:

Mirrors: Aren't they mounted on the doors, from the factory? Then why would they drill holes on the windscreen frame? With DPR mirrors mounted, guessing you don't have an issue with the doors opening and closing?

Factory mounted on the doors. But if you tell them not to install them there they won’t drill holes in the doors (not windscreen).  There is a threaded boss on the windscreen already that will take the dprs. Just not 100% sure what mounting hardware comes from the factory and what dpr needs to supply. The windshield mount does keep the doors from opening all they way to the bonnet but it’s a trade off that I think is worth it as the mirrors are rock steady. 
 

central mirror - right. Forgot about cage. Yes that should work with dpr mount. And it will likely be more stable. My central mirror does vibrate/wind buffet at speed. 
 

8 hours ago, rider said:

Half-Hood: Under what scenarios would be driving with top zipped closed half-way? As for me, unless it's raining, the top stays off! If it's raining (or forecast to rain), Seven will stay home.......

Not sure I would ever easy zip the top and drive. Maybe trying to justify the ez in zip premium.  Like I said I don’t really use the zips.  But I think it looks good and maybe a time will come when I do use it.  But if you’re keeping an eye on the budget maybe don’t opt for that.  I forget how much the zip option added. 
 

8 hours ago, rider said:

 

Questions on heat: Does your pedal box or transmission tunnel (or, both) get hot? If they do, what mitigations you have taken or considering

My footwell doesn’t really get got. The new cars have insulation and carpeting so it’s not too bad. I did a run last weekend and it was close to 100 deg out.  Cruising along wasn’t bad. I did sit in some stop and go traffic which wasn’t great but the footwell area wasn’t a standout problem area (it was boarding on unpleasant all around). 
 

I am reading the other thread about it. But don’t currently see any need to troubleshoot anything. 
 

vintage green with gray stripe and graphite pin stripes.  
 

 

[Xhilr8n]

Your ride has a lot in common with the one I have just taken responsibility for.

 

The choice of safety equipment gets dicy in these cars.  As I understand it from my experience setting up an Elise for full track, there are two ways to go with safety.

 

* Three point and airbags

 

* Seat secured to floor, full cage padded near head, 6 point harness secured to car and cage not seat, helmet, neck protector

 

There are supposed hybrids like the 4 point Asm Schroth offers but I’m skeptical.  One shoulder belt is loosely sewn to elongate as you are thrown forward so your neck is not over stressed= 😵

 

There are more advanced systems with netting on windows etc etc for racers.  Arm retraints are appropriate with an open car.

 

So anything else is a compromise.  We are just choosing what to give up, what risk to accept.   I don’t like driving my track setup Elise on the street because I’m in a twin shoulder harness with no neck protector and my head is near (padded a little) steel tubes with no helmet.

 

I think many maybe most folks assume it’s curtains if anything happens.  Eyes up.

 

 

Edited June 27 by Xhilr8n

[rider]

14 hours ago, CBuff said:

............ The windshield mount does keep the doors from opening all they way to the bonnet but it’s a trade off that I think is worth it as the mirrors are rock steady. 
 

central mirror - right. Forgot about cage. Yes that should work with dpr mount. And it will likely be more stable. My central mirror does vibrate/wind buffet at speed. 
...........

 

@CBuff: Not being able to open the door all the way would be a problem for me. I can see now how windshield or cage mounted mirrors would stop the door! Wouldn't work for me. 

 

@demoray mentioned about Eckels mount which can go on the doors in place of stock mount points. So, it'll be a straight swap then; right? Doors open all the way with no vibration on the mirrors? 

 

Question: We're talking about replacing the stock mirrors with DPR because the stock mirrors vibrate and gets out of position? Is that due to stock mounts or mirrors? 

 

As for the inside, center mirror, car comes with one. Is it not good enough?

 

 

15 hours ago, Croc said:

 

 

 

 

For estimating head clearance, in my car, Lucas is 5'8" and there are no lowered floors in that SV chassis.  

 

@Croc: Yeah, thankfully, the design is improved from yours. Your cage is different though. See the bottom tube which is missing from current Trackday Roll Cage. 

 

Also, as you see, Lucas has plenty of clearance to the top tube. Helmet eats up at least 2-3" of clearance. I'm 5'8" as well, with standard floor. So, I'll have plenty of spacing without helmet.

 

 

4 hours ago, Xhilr8n said:

.......

The choice of safety equipment gets dicy in these cars.  ...... We are just choosing what to give up, what risk to accept.   I don’t like driving my track setup Elise on the street because I’m in a twin shoulder harness with no neck protector and my head is near (padded a little) steel tubes with no helmet.

 

 

@Xhilr8n: Is that Exocet Red? Looks striking. I debated between Exocet and Volcano Red. Volcano is same as my Soul Red Miata; didn't want two same colors. Besides, Seven needs something more brighter than subdued Volcano.

 

Agree on risk management and mitigation. Very familiar with them as a long-term motorcyclist. I'm opting for Trackday Roll Cage based on how it looks near the head and the clearance it offers. 

 

 

 

 

 

[Lancefitzgiben]

For me the Cat has become all about flexibility - it's most common configuration is half hood and full sidescreens, but it's nice to have options. I have full and half side screens, full screen and aero screen, half hood and full hood. The ability to change things around based on weather/use/mood is really nice. You'll have an idea of how you want to use the car in a given configuration, but in reality it will likely change.

 

As others are saying, I'd skip the full cage for street use, especially with 3 point belts.

 

Definitely get 13" wheels and spring for avons. the toyos aren't quite the right size and while they do work okay on a light car - especially for road use they're not that consistent or predictable.