build diary

September 12, 2005:
Still on the dyno, testing different length runners for the intake.
entry 991
Short vs long runners.
entry 992

September 14, 2005:
If you're looking for online gambling just let me know.
My guestbook is suffering an onslaught of spam.

I've ordered a new air filter for the longer runners. It wasn't cheap and if I'd thought about it, I might have been happy with the shorties. Oh well, at least this will idle better. The starting problems have been fixed and all that remains to make the car a little more liveable is to fit a 1.6 throttle position sensor so I can use the idle switch. That will let it idle a bit better but it's actually pretty happy once warm. I also have to cut the hood and I'll probably do that tonight. Then it can be driven!

I've decided against building new solid engine mounts to prevent stress on the frame (thanks for pointing that out, Ted!). Even Caterham uses small rubber bushings as it turns out. Instead, I've installed a set of Mazda Competition motor mounts that are 40% stiffer than the existing ones (or at least, than they were originally). I took the opportunity to lighten the steel portions of the motor mounts as well. They were big enough to handle a small block Chevy before. Finally, a change that doesn't add weight to the car!
entry 993

A view of the throttle bodies from below.
The black part is the throttle cable bracket I built.
entry 994
A short piece of metal and voila - no more bouncy headlights!
entry 995
While installing the stiffer engine mounts, I decided to take some weight out of the engine mount brackets.
They were overkill before.
entry 996

September 15, 2005:
First test drive!
I feel as if the Seven has been off the road for ages. I put the second motor mount in last night and the engine is much more solidly mounted than before. There's no real increase in vibration so I think that upgrade can be called a success! The new rod ends for the upper control arms arrived yesterday and they were installed as well. Then it was time to put the hood over top of the new throttle bodies. This involved a new hole. It hurts to take a saw to my hood but seeing the filter stick out is just too cool. It's cool for intake air as well so that's good. I'm still waiting for the other filter to arrive so I only approximated the shape for now. The headlights were aligned and then it was time to roll the car out of the garage.

How did it drive? I didn't go far due to a little wiring problem with the headlights, but it seems strong. The air intake temperatures stayed low and on closed throttle I could see flashes from the flames coming out the exhaust. Tee hee hee! I still have a bit of work to do before the Se7ens USA trip comes through. A lower windshield so my car doesn't look TOO huge as well as the final hood trip. Who knows, maybe even a grille...
entry 997

A rough cutout in the hood and it fits over the air filter.
I'll refine the shape once my other air filter is here - it's straight sided and not sausage shaped. The wrinkle at the front is some aluminum tape that I put on to protect the filter.
entry 998
I needed a 5/8 x 3" bolt for the upper control arm.
But a standard SAE bolt of that length has too much thread and I wanted to avoid putting a load on the threads. A 5/8" x 4" bolt had the right length shank so I cut it down.
entry 999

September 17, 2005:
The hood is on.
My new filter showed up on Friday. It's HUGE. Still, a bit of careful cutting and I managed to make the hood fit over top. The filter protrudes fairly far and looks like it really means business. Now I can drive the car more. I've also fitted an idle switch so the car will idle better - but more importantly, I can tune the car better. It's fine at wide open throttle but part-throttle needs a lot of tweaking to get it right. Fair enough, we didn't bother with that on the dyno.

The front fender stays are currently covered with wet paint so they'll be final shortly. Now it's just a matter of looking at the windscreen. Just like the first time, it's taking me some time to get started on this. I know it'll be a quick job. I just have to DO something.
entry 1000

The new filter compared to the old.
It's much larger.
entry 1001
Sevens always look cool with the engine bursting through the hood.
entry 1002
I'm pretty happy with the fit of the hole for the filter.
entry 1003
The idle switch for the throttle bodies.
The wiring is a total riot right now due to redundant bits and rerouting compared to the original design. I'll clean it up shortly and replace these temporary connectors with the proper one.
entry 1004

September 19, 2005:
More driving!
The car's pretty happy. The throttle response is fantastic and the car pulls hard. I spent some time tuning the computer and even managed to get rid of most of the flames on overrun. There are still some little problems though. The throttles don't always close fully unless I snap them closed but that's only obvious driving in traffic - I'll find I have an 1100 rpm idle at a light. I'll have a close look at the linkage. It seems to be related to heat. The car also seems much more eager to turn left than right. It could be my weight or it could be a toe problem in the rear. Eyeballing things, it appears the right rear is toed out but I don't trust the rear fenders to be straight. I'll check it today with tools instead of eyeballs.

Polishing the spare wheels yesterday revealed that the perfect tool for the job is seveal grades of Scotchbrite (or a reasonable facsimilie thereof) because it's fast and easy to use. The new wheels look good and are being painted now. I also cut up plywood for the new, lower windshield and discovered that the aluminum channel I use for the frame is no longer available in 8' lengths. All I can get is 4' but that's not enough to go around the windshield. Argh. I'll have to find a solution to that.
entry 1005

September 20, 2005:
The new brake pads arrived today.
To ensure they work as well as possible and to minimize material transfer, I decided to put on some new rotors. Nothing fancy, just NAPA brand. Turns out my price for those is $12 for the front and $10 for the rear! Yowza. It's cheaper than having rotors turned.
entry 1006

September 21, 2005:
For those who haven't heard, there's a large group of Se7ens on their way across the US.
They're in Texas at the moment and having a ball from the reports I've heard - although the roads will get more interesting soon. The cars are loaded heavily as you can see in this photo. Good luck guys, I'll see you on Friday!
entry 1007

September 23, 2005:
I'm off tonight to head for Durango to hang out with all the Se7ens for the weekend.
Due to the chance of bad weather (it was snowing on Hwy 550 last night) and the fact that Janel is coming along, we'll be travelling in her supercharged Miata. That'll be a bit embarassing but at least I'll have the Seven out for when the group comes through Grand Junction. Lots of pictures should show up on Monday.
entry 1008

September 26, 2005:
That was a most enjoyable weekend.
Se7ens everywhere. I was like a little kid running around looking at them all and investigating their little details. A big thanks to Janel for being so patient with me. She's a smart girl and brought a book along.

Westfield, Ultralites, Caterhams, Lotuses, Robin Hoods, Strykers and probably at least one other make I've forgotten. It was very interesting looking at all the various engineering solutions. I pestered a lot of people about their front wheel rates as I'm trying to get a feel for what mine should be.

As I mentioned earlier, we had travelled over to Durango in Janel's supercharged Miata. It looked huge. I suspect even my Seven would look huge in that company. The Miata did help a number of Se7en USA drivers to identify me, though. I spent most of the day wandering around and sticking my nose into various jobs underway - sorting out an overheating crossflow, cleaning plugs on a VHPD K-series, trying to diagnose a running problem with a 400 cubic inch Chevy smallblock (yes, in a Seven). Note that I was sticking my nose in, not actually doing anything to help. Still, I was able to help out a couple of cars by sourcing parts that they'll pick up tomorrow in Grand Junction. The most common complaint on the part of the cars was running rich. Carbureted cars were suffering typical high-altitude ills but even some of the fuel injected ones were suffering. They run off pure throttle position instead of using manifold pressure - that's an understandable thing to do with a big cam and throttle bodies. The problem is that it can't deal all that well with massive ambient pressure changes. I hadn't thought of that before, although I had considered running TPS control on my car. Maybe I won't then.

I hopped in to a couple of Caterham SVs to see how they fit. One had a lowered floor and was cavernous inside. The level of detail overall was wonderful to see and I may end up fabricating some new control arms from their designs. Much cleaner and lighter than my own.

We tucked in behind a group of three cars led by one of the tour organisers and had a high-speed run over Wolf Creek Pass. Turns out a 150 rwhp supercharged Miata can just about keep up with a carbureted 140 crank hp Caterham that's loaded with two weeks worth of luggage and suffering from 10,000' of altitude. Soon after, we let the Se7ens romp off into the distance and took things a bit easier to enjoy the view. The fall colors were at their peak and the weather was perfect, making it a hugely enjoyable trip.

One thing I did do over the weekend was measure a number of louvre setups in hoods. It turns out Birkins use 3" holes like I am, so I used one of their cars as a base for my venting design. The other Se7en owners did confirm that 1) the transmission tunnel is always hot and 2) the hood will always lift up above 90 mph, louvred or not. The hood is off being punched right now so I should have it in time for tomorrow's visitation of Se7ens. Let's hope the little orange beastie does me proud.
entry 1009

Number one of the Good Ideas To Steal: springs to hold the slip joints together in the exhaust.
Very strong springs according to the owner.
entry 1010
Caterham louvre arrangment.
If I interpreted things correctly, the center group is an air intake for the heater. These are 6" louvers, 7 to a group.
entry 1011
Earlier Birkin louvres.
3" holes, 6 to a group. Later Birkins had more holes. More hole than hood actually.
entry 1012
Setting up my own louvres.
This is a simple trick to find the middle of a panel. Run tape from one side to the other, then fold it back until the end reaches the start. Idiot proof and much easier than trying to measure.
entry 1013
If you squint, this looks like louvres.
Doesn't it? Well, once the holes are punched it will.
entry 1014
Caterham bracing at the front of the car.
Holy cow, there are tubes everywhere.
entry 1015
Caterham front control arms.
Clean and very simple.
entry 1016
Winner of the "Caterham I most want to take home" award.
An orange R300. Oooooo.
entry 1017
How do you fit two weeks worth of luggage in a Seven? Well, maybe "in" isn't the correct term.
entry 1018
All hotel parking lots should look like this.
With 50+ cars, it was impossible to get more than a small fraction in a photograph.
entry 1019
Three Sevens, a Miata and some fantastic roads.
Shortly after I took this picture, the Sevens disappeared into the distance.
entry 1020
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