You know the feeling. When you JUST have to take ‘her’ out for a spin – no matter the condition.
You can’t see in this pic, but there’s no hood, no t-tops and lots of body work to be done….. but great looking rims and new meat (tires)…it was running a bit rough but still sounded good!!!
Got an unfinished project but still take it for a spin. Post up a note and a pic.
Another common problem, especially among home mechanics (yours truly included) is the issue of bent fins. Radiator design hasn’t changed much in the past 100 years, save for switching the tanks from a top-to-bottom setup to a crossflow (side-to-side) setup. In all radiators, hot water from the engine flows into the radiator, and then passes through a number of narrow tubes with fins on either side. Air flows over these fins (either from forward motion or pulled through by the fan) which dramatically increases the ability of a radiator to shed heat, allowing the water inside to drop as much as 30 degrees before going back into the engine block.
As important as these fins are, they are also extremely delicate, and sometimes us home mechanics have the bad habit of banging and shoving parts like the radiator into place. This can bend and damage the fins, which is never a good thing. “Any time you bend that fin, it will prevent the air from going through the radiator,” says Jason. “This will in turn effect how it can cool. Small rocks can bend fins, or if you hit a bird or debris on the road. If you’re into driving off-road, mud or dirt can get into those fins too, blocking the air the same as a bent fin would.” Jason recommends giving your radiator the occasional blast of water to blow out debris that collects over time.
A close-up of what bent fins look like. While a few bent fins are nothing to worry about, anything larger than the size of a baseball could dramatically reduce the ability of a radiator to shed heat.
Our New AFCO Dual-Pass Radiator
To compliment our crate engine in our project car, we ripped out the stock radiator that was consistently failing us and outfitted it with a brand new dual-stage AFCO radiator. Beyond cooling though, what are the advantages of upgrading a radiator?
All Aluminum design allows us to take a little unneeded weight off the nose of the car.
The dual-pass allows water to stay in the radiator longer for additional cooling.
100% pressure tested before it leaves the factory.
If you have bent fins though, don’t get too worried just yet; a few bent fins here or there isn’t the end of the world, or even your radiator. “If you have some decent-sized areas, like baseball-sized or larger, that could greatly affect the way the radiator cools,” says Jason. Even if you have a large area of bent fins, chances are your radiator can still be saved so long as the cooling tubes themselves aren’t pinched. “Most auto parts stores sell or loan what they call a radiator comb, which is used to straighten the fins back out. Unless the fins are broken, you should be able to straighten them out.Digging Deeper Into The Cooling System
Dirty and corrosive coolant, loose hoses, and bent fins are common causes of an overheating engine, but sometimes the problem is deeper than the radiator itself. In maintaining our “Fix the simple stuff first” theme, it’s time to start looking outside of the radiator for overheating issues. “You have to make sure that the water is flowing through the engine,” explains Jason. “Stuck thermostats will impede that flow, as well as a blockage a radiator hose. It could also be a sign of a broken water pump.”
“A lot of cars these days are equipped with electric fans. A pretty good sign that you have a fan problem is if your car overheats while you’re sitting on the grid or under caution, but while you’re moving the temperature stays down,” says Jason.
If you’ve gotten this far, but are still having cooling problems, the issue could be one of the most dreaded engine malfunctions known to mechanics the world over; a blown headgasket. For the average passenger car, a blown headgasket is a problem that can be ignored for a quite a while. For serious racers though a blown headgasket could mean a whole lot of damage to the engine, including the radiator.
Replacing a head gasket is a lot more involved than replacing a radiator, or thermostat, and so you want to be sure that that is really the problem. “If you do a pressure test on the radiator, and it doesn’t hold pressure, that could be a sign of a blown head gasket,” explains Jason. “If you’re losing coolant but don’t know where its going, you could have a blown head gasket. But you’re going to want to run further tests, like a cylinder leak down test first. If you’ve got coolant in your oil, it is a pretty good sign you have a head gasket.”
The Football Blowout Issue
But what if you check to ensure the radiator isn’t leaking, the thermostat and water pump is working, and you fix the broken head gasket, but the system is still not cooling right? That blown head gasket may have damaged your radiator more than you know. As Eric Saffell over at AFCO Racing explains to us, excessive internal pressure can be a very big problem. “The case I want to talk about is a racer who sent us back his radiator due to a cooling issue,” says Eric. “Naturally you want to make sure that the thermostat and water pump are working, and that the radiator itself isn’t leaking. This case that all checked out.”
The left side of this radiator is what a core should like; the right side has been “blown up” by excessive internal pressure caused by a leaking head gasket.
However, if an engine loses a head gasket, all of that compression (in the cylinders) has to go somewhere,” Eric explains. “If the engine is leaking on the compression stroke, that compression is leaking into the water cooling system. The capillary tubes, which are wide and very flat, can be deformed by this pressure, taking on an almost football shape, pointed on the ends by rather thick in the middle.”
“What happens,” says Eric. “Is that the pressure essentially crushes the fins, restricting airflow through the radiator. In that instance, you’ll have a particular section of the radiator, or in a worst-case scenario, almost the entire core of the radiator, and you’ll see all the fins look like they’ve been smashed. A quick check for this is to drain the radiator of all the fluids, take it out of the car, and hold it up to the light. If you can’t see look through the radiator, you want to do a more thorough visual inspection.”
“In this case though, you could see that the whole core itself was swollen in a football pattern. The common thinking is if a radiator isn’t leaking, it’s fine,” says Eric. “We’ve probably seen this more in circle track applications, but with power adders becoming more commonplace in drag racing we’re likely to see this happen more often there as well. You know when guys lift the head, they don’t think they’re damaging the radiator or cooling system, but in this case a lot of damage was done, and the only solution was to replace the radiator completely. If you had a pressure checker in the cooling system, you’d definitely see a spike in pressure in the cooling system in cars where this happened.”
Chemistry In Your Coolant
As of late, Eric has also seen the increasing use of cooling additives in the radiator. Back in the day, a lot of radiators were made from brass or copper, but today radiators are more and more made from aluminum. These metals all have different properties, and mixing and matching can be corrosive. “Sometimes you’ll have guys who find an old bottle of radiator additive and they’ll add it without thinking, causing a chemical reaction within the radiator that can eat away at the internals. It will eventually find a place to create a pinhole or a series of pinholes.” To avoid this, just make sure whatever stop leak or cooling additive you use is designed for an aluminum radiator (if that is what you’re using…which you probably are.)
Corrosion is a silent killer, and can be caused by anything from old, dirty coolant to improper additives, or even a poorly-grounded ignition system. Bent fins don’t help much either.
Another problem? Electrolysis. “When the ignition system isn’t properly grounded, the electrical current can run through the chassis and through the radiator,” says Eric. “Electrolysis can cause rapid corrosion through an electrochemical reaction in aluminum radiators. You can actually measure the electrical current in the chassis and the radiator.” The easiest way to check for electrolysis is to hook up a test light to your radiator while turning on the car and making sure you ground your ignition system properly.
For such a simple-yet-integral part of an engine, there seems to be a million and one things that can go wrong with them. But if you start off your diagnosis with the simple stuff, chances are you can save yourself a whole lot of time and frustration. Sometimes though a leaky radiator is a symptom, rather than a cause. This guide should help you get through some of the agony and irritation of fixing an overheating problem, and hopefully next time your radiator springs a leak you’ll be better prepared get it back to working order. And big thanks to Jason Danley and and Eric Saffell for helping us put this article together.
The 1932 Buick had a Ride Regulator. Yup. It was a manually controlled suspension adjustment system was by moving a six position lever on the steering column.
It also featured a button next to the clutch pedal would activate the vacuum-operated Wizard Control for clutch-less shifting.
Cars have come a long way from their roots as steam-powered horse carriages, but the internal combustion engine will always have an Achilles heel; overheating. It doesn’t matter how old your car is, all cars are susceptible to overheating, especially out on the race track where they can run at wide-open throttle for a long, long time. Nobody likes to see that temperature gauge start creeping up, as it could indicate any number of engine issues from a leaky radiator to a blown head gasket.
For such a simple-yet-integral part of an engine, there seems to be a million and one things that can go wrong with a radiator.
A good mechanic always starts by checking the simple stuff first, so for the purposes of this article we will focus on diagnosing a busted radiator. Much of what we discuss here can be applied to a broad spectrum of motorsports, as well as non-racing endeavors. When it comes to pushing an engine to its absolute limit though, there are few events as demanding or brutal as circle track racing.The Common Cause Of Corrosion Is You
The obvious first step to diagnosing a busted radiator is a visual check, inspecting for leaky hoses, loose fittings, and so on. Sometimes finding a leak requires running the engine; other times it can be done by just looking under the car. Checking and tightening all the connections is a great first step, but a leaky radiator is usually just a symptom of a deeper problem, and diagnosing why your radiator is leaking is a job best left to the experts.
That’s why we turned to Jason Danley of Speedway Motors to fill us in on some of the most common issues when it comes to diagnosing a damaged radiator. “The biggest things with radiators are internal corrosion and leaks, damaged fins and a clogged radiator,” says Jason.
Radiator damage can take on many forms, though the two most obvious issues are corrosion and bent fins.
“On passenger cars the biggest issue with radiators is that people don’t change their coolant enough, or at all. What it will do is actually corrode the inside of the radiator, blocking passages and restricting the water, preventing the radiator from passing water through the passages to cool it. I’ve actually seen that corrosion break loose from the radiator and spread to the water pump, intakes, and even the engine block,” says Jason.
If the corrosion goes unchecked, it can even eat away at parts of the radiator and cause small holes that will only get bigger over time. These small holes can be difficult to find via visual inspection, so Jason recommends using a pressure checker. “Auto parts usually have these, and you just put it in the place of a radiator cap and make sure your cooling system is holding the pressure it is designed for,” says Jason. “The pressure depends on the car and the radiator manufacturer, though it is common for radiators to hold between 10 and 12 PSI.” Again though, that number depends on the specific radiator.
Depending on the age of your car and the condition of the radiator, corrosion may or may not necessitate a replacement radiator. If you want to keep your radiator in good condition though, the simple thing to do is replace the coolant every now and then. “The general rule of thumb is to change it every two years at least,” explains Jason. “If you’re putting a lot of miles on whatever you’re driving, you’ll want to do it more often.”If you do find yourself with a leaky radiator caused by corrosion, you may consider using one of the many magical fluids claiming to stop leaks. “Those will work on pinholes on a radiator, or something like that,” says Jason. “The big thing with that is every time you change the fluid, you have are going to lose that stop leak, so you have to reapply it. And if you use too much, it cold plug up the system, preventing water from flowing through the radiator.” As we’ll see later, it is also important to ensure that you’re not causing a chemical reaction with whatever additive you put into your radiator.
Bent and busted fins like these can causing serious cooling issues.
This is the series where I list up the power plant offerings for the year.
Now you would think that being a GM division that Oldsmobile would have the 350 and the like, but the had their own unique engines.
First up was the 225 cid. Oh…a straight six….NO…..a V6!!!!! This was an iron blocked overhead valve engine. The bore and stroke were 3.75″ x 3.40″ and with a compression of 9.0:1 it laid down 155 hp. It had four main bearing and topped with a 1 barrel Rochester Type BC one barrel. This was the lowest level engines and refered to as the F-85 and Vista Cruiser series.
Next up is the smallest of the V8’s offered that year, the 330 cid also in the F-85/Cruiser series. It was an iron block engine as well. The compression was 9.0:1 with a bore of 3.939 and stroke 3.39″. When ou topped that off with a two barrel Rochester Type 2GC carb you could manage a stout 250 hp.
I ran across on ton http://www.corvettereport.com and thought I pass it along. If only they made some of these!!! You got to check out the 1991 C4 body.
Hot rodder Shinoda teams up with Bill Mitchell and defined the “Corvette look.”
Perhaps it was “in the stars” that Larry Shinoda was in the right place at the right time. If you strictly look at Shinoda’s resume in 1956, you might ask, “How did this guy get in the front door?” As a young man, the only thing Larry ever graduated from was high school, Army boot camp, and the School of Hard Knocks. Twelve-year-old Larry had his life turned inside out when along with thousands of Japanese-Americans, he and his family were sent to interment camps for the duration of WW II. The experience had a profound effect on his personality. A self-professed “malcontent” Shinoda could be a little difficult to work with.
After his Army tour of duty in Korea, Shinoda attended Art Center School of Design in Los Angeles, but truly hated being there. He could see no purpose in taking the classes in design and the various art mediums, such as watercolor painting. He was a car guy/hot rodder and he wanted to draw and design cars! So he left Art Center without graduating and based strictly on his car illustrations, landed a job at Ford, then Studebaker/Packard. Just a year after starting his career, he landed a job as a designer at General Motors.
The rest is the stuff of legend. Street racing and blowing the doors off of Bill Mitchell’s souped up Buick and quickly being taken under Mitchell’s wing. Things like that happens, but rarely. There was obviously some chemistry between the two men, perhaps it was because both men could be brash and had strong opinions.
Shinoda got his first big break when Mitchell tapped the 28-year-old to translate the body design of the ‘57 Q-Corvette on to the mule chassis from Duntov’s aborted Corvette SS project. The finished car became Mitchell’s 1959 Stingray Racer, which formed the styling theme for the ‘63 Corvette. From there, Shinoda got one peach project after another. It’s worth noting that the design of the Stingray Racer is held in such high esteem that current Corvette chief designer, Tom Peters (C6 Corvette and late model Camaro designer) is on record stating that his ‘09 Corvette Stingray Concept (aka Transformers Corvette) was influenced by the ‘59 Stingray.
During his almost 13 years at GM, Larry designed numerous special Corvettes, Corvairs, and several race cars, as well as his usual duties working out the styling details of various production cars. Presented here are Larry Shinoda’s most important Corvette designs. Later this week, we’ll take a look at Larry’s very slick Corvairs, and race cars, including the body design for Pat Flaherty’s 1956 Indy 500-winning Watson-Offenhauser.– Scott
1959 Stingray Racer The 1959 Stingray Racer is still a stunningly beautiful car design. The idea of a “broad, flat top surface” was to create a reverse airfoil that would pull the car down. The problem was that the sharp leading edge was too high and at high speed, more air was knifing under the car rather than going over the car, causing a serious front lift problem. The production Sting Rays and even the Grand Sport Corvettes all had the same trouble. This could have been corrected with a slight forward rake, if the nose had drooped down a n inch or so, and a chin spoiled was added. The Grand Sport replica cars from Duntov Motors use these corrections and front end stays where it belongs at high speed – DOWN.
1963 Sting Ray Concept Art The road to fully worked out new car designs was littered with concept art – most of which was probably thrown away. Here we see a headlight treatment study. Sorting out the production car’s rotating hidden-headlight design was a brilliant but challenging project. Note the absence of hood lines and windshield wipers. It also looks like they were considering scoops on the back edge of the doors.
1961 Mako Shark I Showcar – AKA “The Corvette Shark”
With the basic Sting Ray design approved for production, Bill Mitchell had Shinoda design an exaggerated version for a teaser show car. Known today as the Mako Shark-I, the car’s original name was simply, “Corvette Shark.” 1961 was still the “Jet Age,” so the car was originally shown with a plexi bubble top. It was kind of “Jetsons” neat-looking, but would anyone really want one for their daily driver?
1963 4-Seater Sting Ray Split-Window Coupe
The XP-720 4-Seater Corvette Sting Ray was an exploration into the possibility of the Corvette competing with the much better-selling Ford Thunderbird. Ed Cole, head of the GM car and truck group, thought it was a pretty good idea. After all, GM is in the business of selling cars – LOTS of cars. Since the public bought 73,051 Thunderbirds in 1961, compared to 10, 939 Corvettes, it seemed like a no-brainer. The story goes that a tall executive got stuck in the back seat and needed quite a bit of help getting out. The 4-seater concept was quickly dropped. Good!
1963 Production Corvette Sting Ray Split-Window Coupe
Look at 1963 cars from America and Europe and there’s NOTHING like the Corvete Sting Ray. The split-window was one of Bill Mitchell’s pet design elements and was a one year deal. Although the design concept of a “split rear window” wasn’t new with the Sting Ray (the 1950 VW Beetle had a “split” rear window), the overall presentation of the Split-Window Coupe Sting Ray looked like NOTHING else.
1964 XP-819 Rear-Engine Corvette Engineering Study
The Corvair was the only production car to come out of Ed Cole’s ‘57 Q-Chevrolet initiative and was considered very exotic when it came out in 1960. But trouble quickly set in and it wasn’t just Ralph Nader’s doing. The early Corvairs were not good cars. But the “rear-engine” concept was very alluring to Chevy engineer Frank Winchell. Frank insisted that with the correct size tires the inherent oversteering problem could be corrected. Winchell envisioned a rear-engine Corvette and Zora Duntov said, “No!” To prove his point, Winchell had Shinoda design a pretty body to cover the big V8 engine hanging out behind the trans-axle. Upon seeing Shinoda’s rough full-size drawing, Duntov asked, “Where did you cheat?” Where he cheated was that there were no real rear bumpers or crash zone on the back end. The concept was quickly dropped. it was also discovered that the car did excellent wheelies!
1966 Running Mako Shark-II Showcar
Bill Mitchell verbalized the parameters of the design and Larry Shinoda and a small group of designers and stylists worked out the details. It was as if lightning had struck twice – first with the Sting Ray and a few years later with the Mako Shark-II. The exaggerated fender humps have become THE signature Corvette profile. A non-running full-size version was shown to GM’s management in ‘65 and received unanimous approval as the next Corvette. While the new body and interior designs were being worked out, a second “running” Mako Shark-II was built to keep the Corvette fans stoked. Almost 50 years later, the Mako Shark-II is still a jaw-dropper!
1991 Mears-Shinoda C4 Corvette Body Kit
Larry left GM in 1968, stayed at Ford for one year, then formed his own design studio where he worked on all kinds of automotive and non-automotive design projects. Corvette body kits and add-on parts became very popular though the ‘70s and ‘80s. Three-time Indy 500 winner, Rick Mears teamed up with Shinoda and businessman Jim Williams in 1991 to create and offer the Rick Mears Special Edition Corvette.
Arguably the cleanest full-body-kit ever offered for a C4 Corvete, the coupe version lowered the coefficient of drag on the car from .34 to .30. The complete kit cost approximately $5,200, plus $3,000 for installation, and around $1,000 for a new paint job. With a cost of just over 10 grand on top of a $32,455 new ‘91 Corvette, there weren’t many takers. But, it was a very nice design.
Shinoda C5 Sting Ray Concept
The all-new C5 1997 Corvette was released in the Fall of ‘96 and Larry Shinoda got right on it. Note the date on the rendering, “1-6-97.” Obviously, Larry wanted to see more “Sting Ray” in the new C5. If you’re a mid-year Corvette fan, Shinoda’s concept looks pretty good. Larry died the following November and to the best of my knowing, there was never an effort to make a full-body kit based on what may well have been Larry’s last Corvette design project. Any fiberglass fabricators out there that would like to take a shot at the Shinoda C5 Sting Ray???