mark belrose

Not sure yet about that one yet. The JE's I have were designed to run at 13:0 compression at zero deck height with my N42 head and 1mm head gasket. I'm debating running more deck height to get a bit more compression; seems that most of my other motors ended up around 13.5:1 with no problem blowing head gaskets. I don't see much advantage of going higher than that. I guess if we overshoot it I can always go to a 2mm gasket. BTW I'm looking into acquiring a set of PAR billet rods from Australia. Apparently they are somewhat cheaper than Carrillos and can be got in a few weeks vs several months. Mark

I'm currently building an L-series stroked race motor using a diesel 83mm stroke crank. This motor's configuration is much different than normal as I'm using some special JE pistons with very small pin height (1.116"). The person I got the pistons from ran them using a 240Z crank, vs. the stroker crank I'm going to use. I have the build sheet on the rods he'd used with those pistons. Rod length was 142.24mm using a 73.7mm stroke 240Z crank. Deck height was zero. So if I'm doing my math correctly, the difference in stroke between the two cranks is (83mm - 73.7mm) = 9.3mm. Half of that stroke is 4.65mm. I figure that when I call Carrillo up to special order, I need a center to center spec of (142.24mm - 4.65mm) = 137.6mm. Sound correct? We're going to mock everything us using a stock 240Z rod and measure how far the piston sits below the deck, as yet another check. Should make for an interesting motor when I'm finished. I'm looking forward to seeing how well this long-rod configuration setup will work.:cheeky: Mark '70 restored vintage C Production 240Z

I talked to Napa a couple of months ago and they told me they no longer carry Victor Reinz. I live in Central CA and was able to find them at Carquest. Do you have that chain up in Sac? They only charged about $20 a pop, and I consider them far better than any other stock-type gasket. At least they're the only ones holding up in my 13.5:1 race motor. Mark Belrose '70 restored C Production 240Z vintage race car

I've run high 1:36's there, which is not bad. However, a friend of mine, John Wilkins who is the chief instructor for the Vintage Auto Racing Association, has run considerably faster in a similarly prepared 240Z. I believe 1:34's. Unfortunately there are a couple of highly prepared 911's and 914/6's that are now running within our class in the 1:32-1:33 range. They are prepared far beyond their original "vintage" specifications, weighing 1800-1900 lbs. compared to John and my 2150 range. It's a long story but something we are trying to deal with within VARA regarding preparation beyond the spirit of vintage racing. Mark

Below is the text from my second submission for the Z Owners of NorCal newsletter. Read the Jan 2004 article first for a bit of background on the car. Willow Springs Raceway is the oldest existing road course in California. It’s a fun course to drive but a hard course to get right. Cars in my class, C Production, average about 90 mph on it, but it seems like a lot faster. The track has everything from tight off-camber turns to big sweeping corners where you keep your foot on the throttle and hope the car doesn’t go shooting off the course. The Vintage Auto Racing Association’s April 3-4 event was my third attempt at this track. I had high hopes for the weekend, having gone through every nut and bolt on the car, with everything seemingly looking good. I also had a new set of Hoosier S04 DOT tires that I was going to use for the final. Although I had a good time at my previous two races, my car had not held together, acting as a damper on those weekends. This weekend would prove to be a big improvement. Saturday morning was the preliminary qualifying, where your best lap time places you accordingly on the grid for that afternoon’s qualifying race. I decided to put the new Hoosiers on and run a couple of laps during the morning session in order to “heat cycle” them in. Heat cycling involves getting the tires up to temperature, then pulling back into the pits and dismounting the tires for use the next day. This supposedly increases their durability for future races. My best of three laps at speed placed my 8th on the 26-car grid for that afternoon. For Saturday afternoon’s race, my older Kumho tires went back on the car. Right behind my on the starting grid were three cars that I knew would pass me up if I made the slightest mistake. Through the first few corners I noticed that my car was very loose (the rear-end of the car wanting to slide out). With two laps to go the car’s handling had gotten really bad, and I was having extreme difficulty holding off the other three cars, which were trading places behind me trying to get around. Finally, a Porsche 914-6 dived inside of my on Willow Spring’s infamous turn 9, forcing me a bit wide. I put two wheels in the dirt, but luckily did not spin there as most cars do. The three cars went shooting on by, however. After my off-course excursion, I noticed a strange vibration in the back of the car. Being that I am a bit gun-shy about things breaking, I pulled out of the qualifying race with one lap to go. Upon inspecting the car, I noticed that one of the two bolts holding the differential to the moustache bar had disappeared, hence the vibration. The threads were completely stripped out. With some JB weld and a prayer, in went another bolt. Also, my left rear tire was almost completely shredded. For some quirky reason, tires don’t handle well without tread. If it wasn’t for another 240Z that had also pulled out of the qualifying race, I’d have started dead last for Sunday’s final. There were a lot of cars slower cars between us and the top of the grid. At the green flag, our 240Zs quickly made our way through the field, with the other Z right on my arse. As a matter of fact, he spent the entire race right behind me. I was a little faster in the straights but he handled a bit better. We both ended up passing eleven cars before the checkered flag. It made for a very fun race and a good showing by the Datsuns. Mark Belrose 1970 240Z vintage road racer

Below is the text from my fourth submission for the Z Owners of NorCal newsletter. Read the Jan 2004 article first for a bit of background on the car. The saying, “Speed cost money, how fast do you want to go?” is true in most types of auto racing. At the Vintage Auto Racing’s March 12-14 event at Las Vegas Speedway, this slogan once again became apparent. What makes competition within VARA rather unique is there are often a wide variety of experience and preparation levels on the track at the same time. The track at Las Vegas is a very tight, technical course – the opposite of my last race at California Speedway. Top speed means nothing here; being able to corner well and pull hard out of the corners makes for good lap times. The best drivers in the best machines really have an extra advantage at Las Vegas. Saturday morning’s session is like a time trial, where your best lap time is used to place you accordingly on the grid for that afternoon’s qualifying race. The finishing order of the qualifying race then dictates the starting grid order for Sunday’s final. To spice things up, the few “faster” A and B Production cars at Las Vegas were thrown into our C Production race. For some reason I did not run well during Saturday morning’s session, running 11th best out of 28 cars. One of the B Production cars, a 1965 Mustang, qualified 12th and as a result gridded up next to me for the afternoon qualifying race. The Ford was like a hulking monster next to our 2000-pound cars. When the green flag dropped the Mustang floored it and by taking advantage of his huge horsepower, mowed through the middle of the field, scattering our little cars like dust in the wind. I sort of got a kick out of it except for the fact that the Ford was now in my way and I needed to figure out how to get past him. The Mustang didn’t handle or brake very well but pulled away in the straights. After three laps of trying to get around him, I finally was able to late brake him coming into turn 1. After I got around him, it was like turning on a spigot. I looked in my rear view mirror just in time to see three more C Production Porsches pass him all in one shot. I passed four cars during the qualifying race, and thanks to the generosity of the fastest Porsche 911 driver who decided to make an off track excursion, I gridded up in the 6th spot for the final event. The most exciting part of any race for me is actually before the green flag, when the cars form up in preparation for the start. Once the flag drops, I seem to settle down. That’s probably a good thing too, as when the green in waved there is barely controlled chaos with everyone trying to pass everyone else in turn 1. During this particular start no one gained any positions and the starting order held true to form after completing lap one. The 911 in front of me had a nice gap, as did I over the 914-6 chasing behind. Three laps from the finish I started having trouble downshifting. The 914-6 rapidly started rapidly making up ground when all of a sudden a cloud of smoke erupted from my transmission and I knew that once again my day was done. I came into the pits and proceeded to correct the problem by having some beers with my buddies. All in all, despite not finishing, it was an excellent weekend. The weather was great; we partied with lots of people, and enjoyed our time down on the Strip. Mark Belrose '70 Datsun 240Z vintage road racer

Thanks for the compliment Craig. When I get a moment I'll try and kick another couple of articles over to the racing forum. Mark

For more background, please read the Jan and Feb 2004 articles previously submitted within the General Racing forum. During the weekend of 14-16 February, I had the opportunity to race at the Vintage Auto Racing Association (VARA) Route 66 Classic, at California Speedway. It was a great weekend of racing for most, but due to the many mishaps the event may soon become known as the Route 66 Demolition Derby – more on that later. VARA invited several organizations to share the venue for the weekend, including vintage NASCAR and historic Champ/Indy cars. Some of the early Indy cars were traveling so leisurely around the track, my Aunt Bertha in her ’88 Yugo could have whupped up on ‘em. The NASCAR guys were tearing it up though, with a vintage Jeff Gordon #24 seen racing against Earnhardt’s #3. The circuit requires both horsepower and handling to get around it quickly - horsepower for the long front straight and banked corners 1 and 2, and handling for the technical infield. The course is about 2.4 miles long, with cars in C Production averaging about 75-80 mph. When taking into account that cars like mine are probably hitting 140 mph on the front straight, you can imagine how much slower and tighter the infield is configured. I am still the only competitor running a Zcar in VARA’s C Production, although several more are in the works. It will take a lot to beat the top Porsche 911 and 914-6 cars, as in a lot of money. These guys unload their cars off of semi-trailers and have their own mechanics. From what I’ve heard, their engine cost is typically $12,000 on up, and they run the best of everything. I’m not on quite as extravagant a race budget so if something breaks, I’d better get my butt down there to fix it or it won’t get done. Friday was a practice day to test new equipment and familiarize everyone with the track. The drivers are supposed to take it a little easy, but our sessions deteriorated very quickly to full-blown racing including passing on tight corners and short straights. Saturday was qualifying day for Sunday’s final. The racing was very intense, with several collisions and numerous cars either forced off track by other drivers or by their own ineptitude. I did my share of cursing inside my helmet. A friend of mine in a Formula V (a VW-powered open-wheeled car) had another car literally run right up on top of her with one of its wheels coming within 18 inches of her head. As a result, race organizers read everyone the riot act prior to Sunday’s final. Anyone making an off-course excursion, regardless of fault, would be given the black flag and asked to call it a day. Those involved in contact would be immediately disqualified for that event and the next one too. Gridding up for Sunday’s final, I noticed several vacancies in the line. I’m guessing they got the boot for contact. Vintage racers are supposed to maintain the “vintage bubble” around them, meaning contact it s strict “no-no” and all passing needs to be made cleanly. Maybe some of them popped the bubble. I gridded up in 9th place, a couple of Lotus Elans, an early 60’s Corvette, and my 240Z being the only “not-a-Porsches” in the field. I got an excellent start and was quickly challenging for 4th place behind a 911S and an Elan, when upon braking from 120 mph into a sharp left hand turn my steering wheel slammed to the left and I lost my brakes. Luckily there was a bail-out through the cones, which I took and coasted to a stop. A few moments later I gathered myself and putted around the track back to my pit. The right-front brake rotor mounting bolts had sheared away at the rotor/hub interface. Luckily there was no other damage to my car, and more importantly to the other competitors. I had been having a pretty good time up until my brake failure, which sort of put a damper in the weekend. On the positive side, at least I don’t have someone else’s hood paint etched into my driver’s side door or tire marks on my helmet. ‘Till next time, Mark

Below is the text from my second submission for the Z Owners of NorCal newsletter. Read the Jan 2004 article first for a bit of background on the car. Hi race fans. The 2004 racing season is about to get underway after a brief hiatus. Thanks to my friend Steve McConnell who is the director of the Central Coast Z Car Club, many of the racers are keeping in touch with each other via a race oriented website he created for just that reason. I believe it’s the start of a real Z car racing community. The internet site’s members run the full gamut of driver experience and race car preparation. We have Mike Eckhaus, who has been racing for years and uses his fully prepped C Production 240Z to better the lap times of vast majority of Vintage Corvettes and Mustangs. On the flip side, we have Jose Guerrero and Steve McConnell just getting their feet wet. Their addiction to Z car racing is so acute it’s almost painful. Ron Carter is building a C Production 240Z that is faithful to the original BRE version. VARA instructor John Wilkins is in the process of building a C Production 240Z which will bolster the Z presence within that organization. From what I’ve heard, NorCal has several good racers who I hope to meet. Many of the racers such as myself spend the off-season further developing and refining their cars. I ran the entire season last year with incorrect rear suspension geometry (toe out in the right rear). This made the car very twitchy at high speed. I’m hoping to get the car to SoCal’s Z car suspension guru before hitting the track again. My next event is on Feb 13-15, at VARA’s Route 66 Classic at the California Speedway. The course uses about 60% of the banked oval that NASCAR runs on, and then goes through the infield after making a hairy left turn off the banking. The cars run flat-out on the oval which great fun as you can pretty much run high, low, or whatever line pleases you. This is my favorite venue, allowing my car’s high horsepower to be used to maximum advantage. Unfortunately last year I was unable to compete in the final as my engine blew up during the final practice session. It was a NASCAR-type engine failure, blowing two massive holes in either side of my engine. Oil poured onto the manifold and the resulting smoke completely filled the driver’s compartment. I was totally blind going probably 110 mph. Luckily it was on the Speedway’s front straight so I just kept the car pointed in the direction I had been going and braked to a stop. I don’t think the course workers were too happy about that one. I learned the hard way that correct gearing is like free horsepower, and incorrect gearing blows up engines. I was running a 4.40 rear end last year and bounced off my rev limiter at 8,000 rpm for almost the entire length of the Speedway’s banking. For this next race, I’ve installed a 3.90 welded diff which hopefully will make life a lot easier for my engine. Unfortunately I was a regular attendee at the School of Hard Knocks last season. Some additional lessons learned: HUMILITY. This is a biggee. Like most people I considered myself a pretty good driver (90% of us are above average), but once on the track I was administered a butt whipping. Unfortunately it seems good racers are not born, but developed through extensive seat time and common sense (lots of cash doesn’t hurt either). Corner apexes need to be hit correctly and braking points need to be exact. Believe me, this is not easy. Compound the problem with cars right on your a** trying to pass you and other cars in front spinning out. Plus many of the racers I compete against have been doing this since the Civil War and are extremely hard to pass. CAR PREPARATION: The “Weakest Link” is not a TV show, but something that causes you to watch your final event in the grandstands instead of in your race car’s trick competition seat. Everything must be in top notch shape or it will fail. It’s nice to have a trailer full of spare parts, and many of the millionaires I race against have almost everything just in case. SHIFTING: Smooth shifting is essential for good lap times and drive train longevity. Two of my 510 racing buddies experienced problems here. Both missed downshifts, one losing a rod bearing and the other breaking a cam. Both were done for the weekend. If you have race aspirations and are not proficient at heel and toe downshifting, start practicing now. You should be able to brake while down shifting and notice no perceptible change in the rate of deceleration. Drive your street car this way for practice until it is so ingrained in your driving habits you don’t even have to think about it. There are a lot more “lessons learned” but I believe I babbled on long enough. Until next time… Mark Mark Belrose 1970 restored C Production 240Z

Things are a bit boring within this subforum so I thought I'd start throwing out some of my miscellaneous babblings. Below is my an article which was my first installment for a racing column within the January 2004 Z Owners of NorCal (ZONC) newsletter. The dates shown at the bottom of the article are out of data, but that racing organization continues to put on an outstanding driver training program each year. Other article to follow unless I catch too much hell for these submissions.:knockedou Hi everyone. My name is Mark Belrose, and depending upon whether you like or hate my attempt at a racing column, you can either thank or blame your illustrious editor, Jose Guerrero, for conning me into doing this. I’ll try to bias my writings toward those who are interesting in racing but don’t quite know how to go about it, since I’m now an expert at learning from the “School of Hard Knocks”. I guess I’ll start out with some details on my car, its history, and my first efforts to not look like an idiot on the track. This last year was my first full year of racing my restored ’70 C Production 240Z, primarily with the Vintage Auto Racing Association (VARA). I believe many people choose vintage racing in order to live their lifelong dreams before they kick the bucket. I chose VARA because it is a very professional organization that keeps risks to a minimum. I had dabbled around in road racing for a couple of years prior to that, putting my street car at risk on a few SoCal tracks. My work entails a lot of traveling, during which I spotted a derelict 240Z race car sitting in the corner of storage lot of an auto repair business in Ridgecrest, CA. After several years trying to persuade the owner to cut loose with the car, he acquiesced. The only problem was, I didn’t tell my wife. She has always had serious reservations about my going wheel-to-wheel with other cars on the track. I got the car back to my house on the pretext that I would make some money off of it by parting it out. After advertising the car for a few days and having no takers (little did I know the actual value of some of the parts), I finally convinced my wife to allow me to restore and campaign it. The car turned out to be a major find. It was purchased new off the showroom in late 1970, then gutted and fitted with every piece of equipment offered by Brock Racing Enterprises (BRE). Bill Martin then ran the car as a privateer, competing against the original BRE cars on the West Coast. Along with the car, I received the original logbook showing a history of competing at Riverside. Some or the original BRE-supplied parts: • Shortened struts with 240 front/ 210 rear spring rates • Front and rear sway bars with adjustable end links • Triple 44 PHH Mikunis and custom header • Fittings for external oil filter • Venolia forged pistons • Front and rear spoilers • 14x7 American Racing LeMans magnesium rims (extremely rare) • R190 440 limited slip • 5-speed from a Datsun 2000 roadster • Aluminum cross-flow radiator from a late 60’s Corvette My brother went through the old motor and freshened it up. Despite this, I was getting killed on the straights during my first couple of events – so back to the drawing board. My next step was to go out and purchase a 2.8L GT2 motor from a car that had placed highly at Nationals the year before. Features of the new engine: • 13.5:1 JE pistons connected with Mechart rods • .590 lift Isky cam with fully ported head and big valves • Triple Mikuni 50 PHH carbs with velocity stacks (very rare) • Electromotive crankfire ignition • 12 quart dry sump lubrication system • Quartermaster double disk clutch Needless to say the car was now a rocket ship on the straights. During a school at Buttonwillow, I was passing four or five cars on the front straight. Which unfortunately brings me to my next topic, “Lessons Learned from the School of Hard Knocks”. But you’ll have to wait until next month to hear about that. As a last note, I’d like to encourage anyone with interest to participate in the University of VARA, which will be held at Buttonwillow Raceway on Jan 24-25. It is a great learning venue where you can take your street car and decide if this is something you'd like to get try. You can get info at vararacing.com, but make sure to apply early as the spots will fill quickly. A couple of us are already set to go. If you do enter, make sure to contact me at markbelrose@hotmail.com for info and advice about your car. ‘Till next time, Mark Mark Belrose '70 restored C Production 240Z

If you are running a dry sump, it negates the need for an accusump. There's always positive pressure around the corners since there's no where for the oil to slosh to. Mark

Unless you are running a tube frame car where the front cross member has been replaced with something else, you'd have an extremely hard time lowering the engine. As it was, I had to grind off part of my ARE dry sump pan to get a little clearance with the cross member. It made me a little nervous to say the least grinding away on that pan. My dry sump system is set up very nicely, with the pump on the driver's side. It's all plumbed as shown within the How to Hotrod and Race Your Datsun book or The How to Modify...Book, can't remember which. Email me at markbelrose@hotmail.com if needed and I can go out and take some pictures. There's one or two w/in my gallery on this website. Mark Belrose '70 240Z original SCCA C Production dry sumped, crankfire, triple 50 Mikunis

I agree with Jon that a cable option is the best solution in the long run. If you need a shorter rod, you can do what I did: remove one of the plastic cups, cut the rod to the appropriate length, and rethread it. Mark

A couple of thoughts: First, does that single spring seem overly strong? Hard to tell from the image exactly how much tension it is creating. On my street car I played around with spring tension on my triple 40's for a long time before I found the right combination. In any event, I'd recommend using at least two return springs instead of one stronger one, since if you are running only one and that breaks, you are SOL and risk blowing up your motor. Secondly, the geometry of the linkage at the firewall looks pretty poor. I believe you'd have a lot more leverage if the large rod connecting all 3 carbs was linked to the smaller rod at close to a 90 degree angle rather than the 160 degree or so angle it's at now. Try disconnecting the small rod and with your hand pull on it to see how much effort it is takes to rotate is using the current geometry. You should notice that as it rotates to where the arm is near vertical, it should be a lot easier to pull (again assuming your return spring is not overly strong). To remedy the geometry, it may require loosening and rotating each of the three arms that are clamped to the main linkage rod. Best of luck, Mark Belrose '70 restored C Production 240Z privateer

Hey Ron, I'd read your writeup of Fontana including Steve's mishaps. I wonder if he still has the resources obtaining the parts to fix those trannys. I guess if anyone does, he does. I think I went the right route getting a T-5 vs. keeping those old boxes with irreplaceable parts alive. That'a also my rationale of running a stroker at 13.25:1 vs a 2.4L at over 14:1 to stay competitive. Sure, it keeps me in VARA's "modified" category, but I have no inclination to have to replace bearings every race or two as some of the Porsche boys are required to do. Mark

Looks pretty similar to the setup on Steve Link's brutally fast 510, where he has isolated the carbs from the rest of the engine compartment. It's something for me to consider in the future. Unfortunately my limiting factor (besides not having a running car due to broken crankfire) is driver ineptitude. No substitute for seat time - gotta get my butt out there. Watching the incredible GT2 finish at Sebring last night really got me motivated to get my car back on the track. Mark

Interesting. I wonder how much down-jetting my vintage C Production with triple 50 Mikunis and velocity stacks would require to counterbalance the inlet restrictor. Probably a lot. Anyway, in lieu of the velocity stacks, I've been mulling over fabricating an air cleaner assembly which draws in air forward of the radiator support. Perhaps there might be a bit of horsepower to be gained with the cooler air vs. that collected nearer the header. My unibodied car comes in at 2140 lbs. sans me. It seems if the tube-frame cars need to up their weight to meet min. specs, it would be pretty easy for them to ballast their cars for improved weight distribution. Mark

From the description of the problem it might "pedal fell to the floor", it might be worth investigating whether the pin might have fallen out which connects the pedal assembly to the clutch master cylinder, or that the pedal return spring may have become disconnected. Usually when there is a rapid loss of hydraulic fluid, you'll at least get some kind of initial pedal resistance once as the fluid is squirting out of the closed system, i.e. blown master or slave cylinder seals or crack in the hydraulic line. Mark

Tom, the stamping is "FK RSML10T USA", if that means anything to you.

Bought a set the other day for my race car and they're laying on my workbench right now awaiting installation. They appear to be well designed and the sellers up in Sacramento are very nice to work with. Couldn't get enough castor using the typical TC compression rod kit, so thought I'd give this a shot. Mark Belrose '70 restored 240Z C Production privateer

Oops, I realized that right after posting. I do apologize for my "240Z-centric mindset". Mark

Some may think this is a totally ridiculous idea, but why not go with the stock manifold? I've ran several headers on various L24s through the years, and low end power (what I'd call driveability) always suffers when installing a header on stock motors. In my opinion, it's just a waste of money. If you had better intake via modified carbs, porting, bigger cam, etc... then a header is worth considering. Mark