Answers provided by Danny Kellermeyer.Danny Kellermeyer is a force to be reckoned with in the Corvette racing world. Danny and his team of Corvette drivers have dominated several Corvette club racing series. He has no plans to rest on his laurels after capturing the 2010 and 2011 Sports Car Club of America (SCCA) Great Lakes STO National Championships, as well as the Waterford Hills Road Racing (WHRRI) 2010 and 2011 STO championships. Send us a quick email with your name, location, and a short question.
Congratulations to Danny Kellermeyer for setting new records and making history as the first Corvette to win at NCM Motorsports Park! Read more in the July 2015 DJ Racing Excitement Newsletter...
I have installed a full frame and front/rear suspension from a 1996 grand sport in a Datsun 240z along with V8 and 5 spd. I want to obtain the optimum rear suspension geometry for the trailing arms. Can you provide the optimum angle (degrees) of the upper and lower control arms for track day events. Any sources for detailed suspension geometry?
– Gary Wood
Hi Gary, It sounds like you have a nice track car project going on. The C4 suspension is a great conversion and I have seen them in numerous street cars, drag cars and track cars. It is a basic four link suspension and depending on your applications can be positioned all over the board. A drag car for instance, would want the four link to move the instant center out as the car squatted off the line to help with tire bite. Your track car is a different story however. I don't know if you are going to use the original aluminum arms (which everyone called the dog bones) or not. We raced the C4 a lot and even played with a little change of angles. I can't tell you if ours was true optimum, but it sure worked. The easiest way for me to give you angles was to put my C4 on the rack and measure it for you.
The car has a -1◦ of rake which is lower in the front. The upper link was going down at -20.9◦, and the lower link was going up at a +7.2◦. GM had a lot of great engineers working on the C4 Corvette and came up with a good design as it was. Of course the race teams thought we could always make it a little better. I hope this helps a little and good luck with your project!
I have a 1993 coupe with 2016 wheels (18" front/19" rear). Rear tires are currently 245 35 zr19 and look like they are too small. I would like to put on 245 50 19 p-zero Pirrelli. Will those fit?
– David Schalk
Hi David, You didn't mention if your Corvette was lowered or not. It is also in question what rims you have, as the original ones for 2016 had approximately 56mm front offset that is good for your car, but a 70mm rear which would require a thick spacer to bring the wheel out. These are the specs on the tires you have in question: 245-35-zr19 (25.9" overall diameter, 8.5" tread width); 245-50-19 (28.7" overal diamter, 8.8" tread width). Look at your rim offset and if it all looks good for clearance (both inside and outside of the tire), and if the car is not lowered a lot, I would think the extra 1.4" on the top might clear. But if you have it lowered and if the rim offset is not right, you're going to rub somewhere. We have never run that tall of a tire on the racecars and I'm sure we couldn't as we are lowered a lot. Our front offsets are 56mm and the rear offset is 50mm. Hope this all helps a little as I know this is an expensive purchase and you don't want to find out they are going to rub.
I'm lost what to put in my street-driven vette. It's the original motor 350/350 bored 30' over with 11.01 compression and original stock 202 heads. I would like to do an engine rebuild kit, but not the strokers. I also want to get it blueprinted and Dyno tested to make sure everything is perfect. AC, PW,and PB are all stock. I don't want to change the heads; the crankshaft was replaced back in 1986. I already have a newer manifold and carb. I need pistons, rings, cam, lifters, all bearing, main, rear, camshaft bearings, etc. Wanting more power if that's allowable, without doing major changes. What do you think would be a great kit? And what would you do?
– Kim Quintero
Hi Kim, Sounds like you have a nice engine project ahead! If I remember correctly, the 350/350 was L46, a higher performance version of the base 350 cu in V8, 492 heads with 2.02"/1.60" valves, 11:1 compression ratio and produced 350 hp. It was a four bolt main block, forged crank and forged pistons. At this point in time, if a hod rod guy could get 1hp/cubic inch, they were good. Now the Corvette engineers did this for the consumer. So I would say “Don’t screw with a good thing”. Focus your rebuild on the good stuff. The forged pistons were TRW originally and are still a good replacement. Heavy for today’s weight, but your crank is balanced to that kind of weight. Hypereutectic would be second choice but stay with forged for a good fit and reliability. I use Clevite brand. The cam you have is a good design for road and performance. I’m sure your cam is worn, as all flat tappet cams become, so get a replacement. Most cam companies still service that same grind. Bottom line: it is hard to beat a good thing. That engine was smooth, had low end drivability and upper end performance. Heads flowed well and lower end held strong and tough. That was a well designed and well built engine.
Thanks Danny, and you're right...I don't want to change much. I would like to put in a roller cam and lifters; what would you recommend as a kit? The rest will stay the same except if I need to replace the springs and pushrods. There is so much to choose from, it's mind-blowing. If you could give me your opinion on the retro roller kit, that would be great. Again thank you!
Kim, Thanks for your follow-up question on your engine rebuild. A roller camshaft can reduce the frictional load of an engine, taking less horsepower to turn and generally not wearing out as quickly. An added benefit is roller tappets do not require replacement when changing cams. Roller profiles can be more "aggressive" and accelerate the tappet more than a flat tappet profile. If a cam profile is more aggressive, it has more "area under the curve", which means it can make more power. Make sure the camshaft kit you get is for an early small block and not one for a hydraulic roller cam late (86 up) small block. Your original 350/350, 1969 Corvette engine flat tappet was 224/224 degrees duration @ .050 lift, so I would get something like this or slightly larger (approaching 230). Stay in the 112-114 lsa. This should give you a little more power and still have drivability. Here is the real concern: price. The roller cam and lifters will be $600-$800. Add pushrods, cam button and you are in the $800–$1000 range. A new flat tappet hydraulic cam and lifter will be $200–$300. The increase in power you want can be achieved with either cam, just depends on your budget. If you choose the flat tappet cam, make sure you apply cam lube (high in zinc and phosphorus) and use oil which is high in zinc and phosphorus. Oils today have eliminated these additives. You can also use a ZDDP oil additive to increase zinc and phosphorus levels. I still do that on all our race engines even though I run a roller camshaft. Hope this gives you a little more insight!
I just bought my first '05 convertible corvette and want to add two things: a classy looking wind restrictor and a pair of hoop roll bars behind the seats. Having searched the web, I have found several restrictors that I like, but few roll bars. Do you have any idea who produces those or do you know anyone who will custom build something like that? Also, do you think I will have room behind the seats for both the bars and the screen? If I cannot fit both restrictor and bars in my car, I was considering the chrome hoops that are mounted with a peel-and-stick method, but that kind of mounting seems a little suspect to me.
– Denny Brune
Mr. Brune, Thanks for writing in! It sounds like your C6 is one of the most personalized convertibles I’ve ever heard of. I’ve seen a few roll bar hoops in C5 and C6 convertibles. I do know SR1, Racefab Inc, and Corvette Central all have one that goes to the bulkhead and attaches there. None incorporate both hoops with a windscreen, however. Personally, I like the one Corvette Central sells for its fit and intrusion into roof space. I remember seeing a Callaway that had a windscreen, but don’t remember if it had two hoops or just one. I’ve seen quite a few decklid mounted hoops that look good but are completely dress up items and, again, wouldn’t have a combined windscreen. I think you would have to go to a custom outfitter to get what you wanted unless you start with one of the 2” seat hoops and combine the two with a windscreen material. That's something one of the Corvette outfitters would have to do, and you are right, there isn’t a lot of room to do all of this on your car. Just remember, any of these are beauty enhancement as they are not intended to improve safety or roll over capabilities. All will have the footnote "does not constitute a roll bar" or "not intended for competition".