The Chapman Report
Published by the Golden Gate Lotus Club
PO Box 117303 Burlingame, CA 94011
Friday January 15, 1999
We have a Track Day ...
Demonstrating a boldness that will undoubtedly cause his already lofty standing in the public opinion polls to skyrocket, 1999 GGLC President Scott Hogben today announced that he has secured Thunderhill Raceway on May 16th as a GGLC Track Day. So dust off the Nomex and check the gauge on that fire extinguisher.
Details to follow Ö...
1999 GGLC Calendar
1 Happy New Year !
15 Membership Meeting - Tom & Cherie Carney's, Burlingame
19 Membership Meeting Ė Don & Bettye Nesterís
19 Membership Meeting Ė John Zender's, Menlo Park
27 Sierra Foothill Tour to DBE & Denhard's (tentative)
16 Membership MeetingĖ Victor Holtorfís, Burlingame
18 Lotus Dyno Day (tentative)
16 GGLC Track Day at ThunderHill
21 Membership Meeting Ė Joel Farberís, San Jose
13 Zender Rallye - Woodside Hills
18 Membership Meeting Ė Hamai's, Palo Alto
4 Esprit Parade, host John Ridley
16 Membership Meeting TBD
16-18 LOG 19 - Lotus Ltd Corning NY *
20 Membership Meeting TBD
27-29 Lotus corral at the Monterey Historics (featuring Auto-Union)
11 British Car AutoX (tentative)
12 All British Car meet Ė Palo Alto
17 Membership Meeting
15 Membership Meeting TBD - Nominations
19 Membership Meeting TBD - Elections
5 The (Toddler) Toy Rallye -Fremont
?? GGLC Holiday Party ,TBD
* non GGLC event
I canít believe itís January already and time to write my first article as president. Itís hard for me to believe that itís been almost 14 years since I joined the Golden Gate Lotus Club at the tender age of just 21! Back then, John Zenderís Europa was one color (and fully stock!), Mike Schlictís car was driven on the street, and Steve Frey wore a tuxedo to almost every meeting. As long as Iíve been a member Iíve heard people reminisce about GGLC days of the past and Iíve always heard amusing anecdotes and a lot of laughter about good times which were had by everyone. Thatís because we have good people and a history of putting on good events, however large or small they might be. Iím hopeful that more great times will be coming your way in 1999 just as they have throughout the years in the GLCC. There are a host of things planned for this year and theyíll be posted in the Chapman Report each month. Some of them might be tentative because of issues outside our control, but hope for the best!
Last year all of you were subjected to my monthly articles and this year youíll have to endure more of the same. At the end of last year I wondered what I was going to write about this year because I thought I had exhausted all that I had to tell. But as you all know, when you own a Lotus, life is not boring! There is always a good tale to tell. Many of you have amusing stories to tell pertaining to owning your Lotus and hopefully youíll find more this year with what is planned, so donít hesitate to tell us about them by submitting an article. After reading the last issue of the CR, I wonít hold back on writing more articles like the one in the November issue regarding Lotusí engine choice for the Elise. I knew some people might get a little worked up over that article (particularly Alan Perry, as we have debated the Honda topic before) but itís okay to write something that generates controversy for the CR since, a) The CR will indeed print ANYTHING, and b) Controversy usually generates a response. Judging by Alanís fire-breathing rebuttal in the December issue, I think he took a few things that were meant to be taken with a snicker a little too seriously, but at least he responded and I thank him for that. I encourage anyone who has something to say to do as Alan did and send it in to the CR.
Before I close, Iíd like to rehash something I wrote last year that relates to the events which are planned for this year. As you may recall, I wrote an article in an attempt to get people to work on their cars and get them ready for spring. Well, itís that time again to get your Lotus freshened up for the coming year. Now that the holidays are over, itís time to get your hands dirty and fix some of the things that have been nagging you while you drove your car last year. I for one, have plenty to do on the Seven since I more or less threw the car together to get it to the British Meet. But in addition, Iím determined to fix some of the little things on the Europa like the worn bushing at the bottom of the shift lever, and that clutch cable that keeps sticking, to name just two. Those are the sort of little things that donít stop you from using your car, but they do stop you from enjoying your car, and thatís the most important thing to remember. So, drag your car out of the garage and drive it around the block to refresh your memory as to what needs to be worked on and start fixing things. The weather guessers say itís going to be a dry year and if theyíre correct, youíll want to be able to enjoy as much of it as possible behind the wheel of your Lotus! See you at the next meeting.
The (co) Editor
Itís my turn Ö.
Last year I had enough things to worry about being President. Big things; how to keep the membership up, are we putting things in place that will have us grow as a club, are we ever gonna get that web page going ? And little things too; are we having enough events ? too many ? is anybody going to remember that I said I would repaint my car this year ? One thing that I didnít worry about however, was the Chapman Report, cause month after month it just happened.
Weíd discussed a few changes at the beginning of the year, but after that John just asked me each month when I was going to get him my column. Most of the time I would send him something, and then magically there was the CR in my mail basket the week before the next meeting. I really didnít think about the work that went into putting it all together, on time, and have it looking good.
Well now that Iíve traded in my Presidentís hat for co-Editorís visor I have thought about it, and I have a new appreciation for the way John managed the CR last year. And Iím looking forward to helping him out this year, not only so he can spend more time building the Ultimate Europa, but mostly so I can say "When do you think youíll have your column Scott?" and to everyone else "Send in your submissions".
Building The Ultimate Europa, Part 4
by John Zender (co-editor)
I've lagged quite a bit on getting this latest installment to you. The work talked about in this story was
completed last April and I've put a couple thousand miles on the car since then. In December I disassembled the
car again to begin Phase 4 which will include a full roll cage, vented front rotors, all new wiring, and some
In Part 3 of Building the Ultimate Europa I had finished design of the rear suspension and fabricated prototype
hardware for the left hand side. A quick review of the changes include new Formula Ford uprights with lower
reversed A-arms, single top link, and 2 unequal length semi-trailing arms.
I optimized the forward trailing arm pivot locations through a series of trial and error experiments. I tack welded
the front pivots as far forward on the frame as possible with the arms horizontal. Using a bump steer gauge I
measured the change in toe-in through the suspension travel, and then repositioned the pivots and tried again until I
found the best locations. I settled on a geometry that gave about .002" toe-out during the first 1/2" of bump, and
then about .010" toe-in through the next 1-1/2" bump. The idea here is to produce mild, increasing understeer
as the suspension is loaded in a turn.
The car came together in March and April with completion of the driveshafts and brakes. Special halfshafts
were required to bring power from the Fuego box to the VW CV joints at the outboard ends. There are a few
different ways to go about fabricating a shaft like this using various combinations of components. I chose the
simplest option and built mine using a Europa U-joint yoke and a VW axle. I started by first annealing the VW
axles. I then cut off one end and turned its diameter down to fit into an original Europa TC splined yoke (the one
that the roll pin normally goes through). I fit the axle such that it slipped through the spline's I.D. and protruded
about 1/8" on the U-joint side. Having the axle stick through allowed me to place fillet welds on both sides of the
yoke to produce a very robust connection.
Welding was not as straightforward as I hoped. In order for the joint to be heat treatable after welding, a high
carbon alloy filler rod such as 4130 is required. When 4130 was used, however, the welds would continuously cold
crack immediately after welding. The high carbon filler rod combined with the very high carbon axle produced a
weld that was extremely brittle. To solve the problem, I welded the first pass with a low carbon steel (E70S-2), and made subsequent cover passes with 4130. Dillution of the axle's steel with the low carbon filler produced a crack-
free first bead. After welding, the axles were slow cooled in the oven, and then brought back to the heat treater for quench and temper.
I purchased a pair of Wilwood Dynalite 4 piston calipers with 1.375" bore to mount in the rear. Since the Eagle uprights have no provisions for caliper mounting (the Eagle used inboard disks) I needed to modify them to accept the calipers. To achieve this, I carved 1/2" thick mounting plates out of 6061 aluminum and welded them to the uprights using 4043 filler rod. After welding, the uprights were re-heat treated to a T6 condition to regain the strength lost by welding. I had custom 10" solid rotors and aluminum mounting hats fabricated to complete the brake installation.
The car performed very well on its maiden voyage to Dave Bean Engineering. Since then I've had a chance totune-in the geometries a little more precisely an have been rewarded with a definate improvement in handling over
the old setup. The original S2 Europa handled excellently, but when I first added the Cosworth, TC chassis, Fuego
box and 7" wide wheels, there was always a pronounced bump steer in the rear that I wasn't able to tune out. The
new design has virtually eliminated this annoying handling quirk, inspiring more confidence in the twisties, and
giving a much more stable ride at speed.
Besides the improvement in rear bump steer, the brakes are awesome and I can finally fit those wheels that
have been sitting downstairs for 2 years. Also, the piece of mind I've gained from eliminating the original rearhub/bearing setup should make me infinitely more relaxed on long drives and track sessions.
Who Needs Cool?
Hmmm, reading this morning's paper I see that it was 10 below in Minneapolis yesterday. So, why am I writing about overhauling radiators? Well, because it will be summer again and we will see temps in the 90's and 100's and you will see your temp gauge climb past 210 on your Lotus while sitting at a traffic light in bumper to bumper traffic. So, this article is about the restoration of your radiator.
The radiator is essentially a heat exchanger. Engine heat is carried away from the engine by the coolant. This hot water - glycol mixture is then pumped to the radiator where it flows into a tank on one end of the radiator and then through a matrix of small slender tubes to the opposite end where it is collected in another tank and then back to the engine. This matrix of small tubes is called the core. Nearly all of the cooling takes place while the coolant is traveling through the core.
The cooling efficiency of a radiator is the ability of the core to move heat energy from the coolant to the walls of the small tubes and from the tube walls to the air passing through the core. The core is a made up of tubes that go from one end to the other end typically arranged in rows. A core with one row or layer of tubes is said to be a single row radiator. A radiator with two layers/rows is said to be a double row core. So, there are a number of factors that have immediate and direct correlation to amount of heat that can be transferred from coolant to air.
Air must able to flow easily around each tube the core. The more air that flows through the core the greater the potential to dissipate heat thus the greater the potential to cool. Think of it as a conveyor, the larger and faster the conveyor moves the greater is the ability of the conveyor to move stuff from one end to another. Airflow must be through the entire surface of the core, so any objects that reduce airflow will reduce cooling. Baffles and ducts that direct air to and from the core will enhance cooling.
The tubes of the core must absorb heat from the coolant it contains and be strong and durable to resist punctures and corrosion. Typically metals are chosen with the characteristic of rapid heat absorption. Metals such as copper, brass, aluminum, silver & gold are the best heat conductors. For obvious reasons we don't see silver or gold radiators! Most commonly copper is chosen. Copper is strong, easy to solder and form, but its downfall is weight. Aluminum is often used, but is more susceptible to corrosion and is difficult to weld.
More tubes equals more cooling. Simple! But, if tube density gets too high then airflow is limited and cooling ability drops.
To cool the tube the more surface area that is in contact with the passing air the better the ability of the tube to cool. Knowing this radiator cores have fins attached to the tubes. These fins carry the heat from the tube and dramatically increase the surface area of the tube. Recent radiator core development further increases surface area by the use of wavy fins and fluted fins.
The heat in the coolant can't instantly be transferred to the tube. Think of it this way, if you go to grab the handle of a hot pot lid and you just grab it for an instant you barely feel any pain. But, grab it firm and hard for some time and you get burnt! The thermostat in your engine cooling system serves to control the speed at which water flows through the radiator. Too slow and the coolant in the engine over heats, too fast and the coolant in the radiator does not have enough time to transfer heat to the tube walls.
STANDARD / STOCK
The typical old British 50-60s radiator only had two rows of tubes. The tubes were widely spaced with a few fins. These radiators can only be improved by having them cleaned and rodded. Rodding is where the radiator shop will remove the tanks on each end of the core then physically ram a rod through each tube to clean it out. After that's been done they will reassemble the radiator.
Newer cores will have greater tube density; that is to say the tubes are more closely spaced. Thus the number of tubes will be increased and the ability to cool increased accordingly. The radiator shop will again disassemble your old radiator, but the core will be replaced.
Even more cooling capacity can be had by replacing the core with a core with closer tube spacing, and additional rows. This usually will mean a triple row core. This combination of increased density and three rows will nearly double the number of tubes and cooling capability.
Today's best is taking a Level 2 core replacement but with a core that has louvered fins. This additional surface area on the fins will typically get you more than double your original cooling capacity.
I've taken a number of cars to the Level 2 core replacement with excellent results. Most recently I replaced the core on my S2 Elan. Now, even on a warm 95įF day the temperature never climbs above 90įC. And on days where the ambient temperature is 70įF or below the engine runs on the thermostat!
For Sale: Ď89 Mazda 323 SE, 2-door hatchback. 5spd, A/C, new tires & exhaust, 110k, original owner, $3100/obo. Located in Sunnyvale. Daren (firstname.lastname@example.org) or wk: (408) 527-5044
For Sale Autoscan (FMC) 4050IR auto diagnostics station; dwell, tach, CO, HC. 41w x 20d x 55h, weighs at least as much as a waterbed, but at least it is on wheels. Don't know if it works, but at this price
who cares. $1.00 firm, cash only, no trades, you pick up (there's the catch). Located in Sunnyvale. Daren (email@example.com) or wk: (408) 527-5044
Wanted: Used Europa TC chassis with good backbone and rear section, front end donít matter.John (650) 368-9105
Wanted: serviceable Ford 1600 X-flow block to be bored out. John (650) 368-9105
1990 Caterham Super Seven S3, LHD, long cockpit chassis, de Dion, 5 speed, limited slip diff, heated and tinted windscreen, aluminum bell housing, steel braided lines, BRG with yellow and BRG noses, 4 wheel discs, 10K miles. Kent 1750cc super sprint with forged pistons, aluminum roller rockers, flow benched head. 6.5 x 15 Prisoner alloy wheels, standard and FIA roll bars, adjustable rear sway bar, Spax adjustables, 4 Keizer 3 pc 13 x 8 wheels, Brooklands windscreen. $27,500. John Lefcourte, (702) 829-8589 firstname.lastname@example.org
For Sale: 1969 Elan S4, daily driver. 11,000 miles on big valve, mildly modified engine by Rich Kamp (130-135 hp). Excellent mechanicals, clean body, old paint, original interior. $14,000 Ed King evking@KINGandHIGGINS.com (415) 781-2888
1969 Lotus Elan +2,3500 miles on rebuilt twin-cam and close ratio four speed. (Rebuilt to Big Valve Spec). New Minilites, 008 tires, brakes, Spax shocks, drive train donuts, all new front suspension and steering linkage, new dash and instrument panel, and fresh Lotus computer-matched red paint. This car is ready for daily driving, or vintage racing, with a few modifications. Total of 69500 miles since new. $9500 or best offer. Bob Coover (510-531-1765)