Newbie Questions

[Joespeeder v2.0]

I am about to order my first Seven and have a couple of questions. The spec (as it stands right now ) will be a De Dion Package, Zetec Supersport+5speed gearbox, Wide Track,Watts Linkage, LSD, FIA Bar, Cloth Seats, leather tunnel top, yellow wings/nose.

 

This will be mainly a road car that might see the track twice a year.

 

1. What is the differance in the standard 5 speed and the race version? My dealer said on the standard 5 speeds 1st gear is very short. Does the race version change this? He also said he race box is a little smoother. Any advice you guys can give on these two boxes would be great.

 

2. Should I get the Triple Bypass Aluminum Radiatior?

 

3. What type of tires are standard on the DeDion kit?

 

4.Anyone ever use Jethot coatings on the exhaust manifold? If so, did it cut heat to the footwell by a significant amount? Did you see any change in horsepower as they seem to indicate?

 

5. Any tips or tricks to keeping the aluminum polished? I always seem to do this type of thing the hardest way possible, making the biggest mess I can.

 

6. I've read build pages where the speedometer is reported to be fairly inaccuracte. Is this still true? Any tip or tricks to watch here or is it just a matter of upgrading to a VDO or Stack?

 

7. What brake pads are everyone using for street/track.

 

Thanks in advance for all your help.

 

Joe

[Sheds Moderator]

Nice car. I was wondering "how does he spec a Zetec" till I looked at "location".

 

1.Not sure but the std 5 speed is a bit short on 1st and lo-o-o-ong between 2 3 and 4.

2. Don't know, does it get hot in summer where you are? If you intend hammering it round a track at full noise and 100F+, possibly. Otherwise no, the dealer is obliged to sell you a car that can keep its cool should you decide to take it out on a sunny day.

3. Dunno, in USA. There are thousands of threads on which tyres to use.

4. Most of us use exhaust wrap tape. As for HP gain, by what physical process could wrapping tape round the exhaust improve the power output of a motor?

5. As with tyres there are lots of threads on this.

6. It's true, they all do that sir, if you are bothered fit a Stack or (cheaper) a bike computer. Sigma ones go up to 120mph, quick enough for me.

7. Another one for personal taste. Pagids are felt to be best, at 120 GBP per axle set they should be. Mintex and ferodo versions are more reasonably priced, i have heard good things about Mintex 1144 which is a fast road/track day pad.

 

"Search" is up at the top of the page for popular titles like tyres, brake pads, polishing, cleaning, best kind of underpants to wear when driving, etc. There's loads of useful info there. Good luck.

[Joespeeder v2.0]

Thanks for the reply.

 

The Jethot coating website says "JET-HOT Sterling will normally boost power when applied to headers for two reasons. First, the coating promotes denser, more potent fuel/air charges by insulating the engine bay from exhaust heat. At the same time, it accelerates the pulsed-vacuum effect on “tuned” headers, resulting in more effective scavenging of cylinders. The increased velocity of exhaust gases produced by higher exit inertia not only clears each cylinder more quickly; it also draws in the next fuel/air charge more efficiently. "

 

I just like the idea of a coating that reduces heat to the footwells and engine bay. Any other advantage is secondary snakeoil.

 

My main concern right now is the 5spd. So far I haven't been able to find any real insight into the upgrade. I don't want straight cut gears for the street and although I don't think thats a concern here. That would be an unwelcome surprise.

 

Thanks for yor help.

 

Joe

[Myles]

When you talk about the 'race' box - is this still a 5-speeder, or the Caterham 6-speed box???

 

 

 

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[Joe 90]

Joe,

I don't know what you mean by a "race" 5 speed gearbox, but quite frankly nearly anything is better than a standard box. I've got a BGH modified box, which has great ratios and is a lot cheaper than the Caterham 6 speed box.

 

As for exhaust insulation, I've tried an insulating exhaust paint. It's hard to decide how much of an improvement it's made, but it was cheap. After all, you can always add tape afterwards if it's not good enough. Adding insulation around the footwells is also cheap and easy at the build stage.

 

As for keeping Ali shiny, I just got bored. People have either never seen/heard of Caterhams or the copies, or they know enough to tell them apart anyway, so why not go for a wild paint job?

 

SEP field working, not spotted in 101,600 miles. Some photos on webshots, updated 10 June

[Joespeeder v2.0]

Hi All,

 

The only real info I get about the Race 5spd gear box is on the Caterham US sites engine program spec page. Other than the pricing, the details of the gearbox seem to be vaporware. The lack of real info generated my questions. The page lists:

 

Ford 2.0l Zetec Supersport with Ford Sierra 5-speed transmission: $11,250.00

Ford 2.0l Zetec Supersport with Heavy-duty Ford Sierra 5-speed race transmission: $11,950.00

Ford 2.0l Zetec Supersport with Caterham close ratio 6-speed transmission: $13,150.00

 

The Jethot process is an industrial coating. You ship your headers to them. I thought I might go to this trouble as this is a fresh car/build. Their web site describes the process this way:

 

JET-HOT® develops, produces and applies a variety of coatings for parts exposed to high temperatures and/or corrosive environments. All are applied at one of our regional factories through a meticulous, multi-step process including: thermal degreasing, abrasive-blast stripping with virgin aluminum oxide, double-coating (inside and out on headers), high temperature curing, custom packaging for return shipping, and quality-assurance controls during every phase of the procedure.

 

Anyone have experience with them ?

 

Joe

 

[Sheds Moderator]

Joe, I'm sure the Jethot will make the pipes look nice and it will also reduce underbonnet temps (good for power and above all else comfort, these cars get HOT in the footwells and there is no through ventilation.) As for "magnifying pulse jet effect" or whatever nonsense it was, that's 100% pure, unadulterated snake oil. Were they in the UK I would be reporting this to Advertising Stds, 'cos it's bull.

Re boxes, the 6spd is well loved here. Whetehr you need it with all the torque from a Zetec is questionable. Some people here have modified the ratios on the std Type 9 to good effect (Around 400GBP). It's cheaper than a 6spd, tho' a 6spd will always resell at a good price. In the end only you know whether you want to spend the extra 1900 bucks on it.

[Joespeeder v2.0]

Hi All,

 

Here's the info on the 5spd gearboxs I got from Caterham USA.

 

"The two five speed gear boxes

listed, the std one has helical gears the race one has strait cut gears.

There is one more option, it is the long first gear five speed- that is

supplied by BGH in England. The first gear ratio is around 2.8:1 as apposed

to the 3.36:1 in a std 5-spd. The long first gear five speed is a $750.00

option on any engine package. "

 

From that it looks like I'll get the long 1st gear upgrade on the standard transmission.

 

Joe

[Joe 90]

Joe,

I wouldn't go for straight cut gears as there's no sound insulation in the tunnel. As well as offering a sensible 1st gear, I went for a 0.89:1 5th, which is a big improvement over the 0.825:1 standard. It's also a BGH option.

 

SEP field working, not spotted in 101,600 miles. Some photos on webshots, updated 10 June

[Joespeeder v2.0]

Thanks Oliver,

 

Forgive a dumb question. Why do you prefer the .89:1 for 5th? From looking at the Road and Track test figues, my guess is the standard gear is too far of a jump from 4th and your gearing makes 5th a true 5th gear rather than a highway gear. ???

 

What are people using as redline on the Supersport Zetec? Max RPM 7,500/Max Power 6,800

 

This is going to be fun

 

Joe

[Joe 90]

If you do a search for a nifty little utility called gearcalc, you can see the effect of different ratios. With the standard 5th speed, my car would be geared for 149 mph, and you need about 280 bhp at 6500 rpm to pull that kind of speed in a seven. With the 0.89 5th, that drops down to 138 mph, which I can't pull either, but it still improves cruising.

 

SEP field working, not spotted in 101,600 miles. Some photos on webshots, updated 10 June

[Steve Stephens]

Joe,

I am going with the BGH 5 speed from Caterham USA. I do believe the box I'll be getting is the E6 box from the chart on this page

 

http://hometown.aol.com/dvandrews/bghpage.htm

 

but have sent an email to confirm.

 

The choice of gearbox and rear end ration was a hard one for me but I ended up with a 3.92 rear for my Superlight R with Zetec SVT engine of about 185 HP. From what I can tell, the Zetec and Duratec have a broad torque range for which the 5 speed may be better than a 6 sp. Caterham USA's 25 hr. racecar used a 5 speed and the SVT engine.

 

Have you sat in the cloth seats? I find that they don't fit my body (too much curve on the backs) while others seem happy with them. I like the Tillots and will be getting them.

 

Give Caterham USA a call and they should be able to help you with your questions about the tires, radiator, etc.

 

Steve

 

Edited by - Steve Stephens on 1 Jul 2004 06:38:27

[Sheds Moderator]

Gear ratios are a religious subject for some here and as ever are a compromise. The long 5th of the standard type 9 makes the car easier on motorways but is useless at speeds under 60. If you lower it and bring it closer to 4th it will be better for "fast road" driving but the price is thet you will be doing (say) 4000+ rpm on the motorway at 80, which is noisy and hard work. It depends what you want to do with the car.

[Graham Perry]

Your decision to go for the BGH long first ratio 5 speeder makes sense. I have run one for years and it is no more noisy that a standard box. Lots of people run them here as they are cheaper than the 6 speeder, and offer a useable set of ratios that suit a seven.

 

One other thing about your spec. Many people find soft top cars and cloth seats don't go together if you live in a rainy area. After a good soaking they may never quite be the same again.

[Joespeeder v2.0]

Hi All,

 

I have sat in both the leather and the cloth seats. I like the cloth as far as feel and fit, However, the I'm naturaly drawn to the leather. After trying both I thought why not save the money and get the seat that fits best. As far as water soaking, I've read opinions that the cloth drys faster/better than the leather. What does everyone think? Since I know at some pont the car will get rained on, do people prefer cloth or leather for wet weather?

 

As for the gearbox. I guess I'm still undecided on 5th gear. This will be a roadcar mainly. It will see the track once or twice a year at some of the smaller tracks I see each year.

 

I plan to use it much like Angus and Tessa at mycaterham.com. As I have a track car already I'm leaning toward the standard 5th gear. The taller 5th gear may be better as a travel gearing. Does this make sense? Funny part is the 7 will stomp on my track car, a 911.

 

Thanks for everyones help.

 

Joe

[Joe 90]

Joe,

Our car did 100,000 miles with a 4 spd box, and I've only recently converted it to a BGH 5 spd. IMHO the 0.89:1 is sufficiently relaxed, and the 0.82:1 is a waste of time.

 

SEP field working, not spotted in 101,600 miles. Some photos on webshots, updated 10 June