I have a 1971 Demon that I would like to lower. It will have a small block and front disc brakes. It will have 18-inch wheels and will be street driven with an occasional quarter-mile trip.
Rudy, achieving a lowered stance can be as simple as adjusting the torsion bars down, and using rear springs with zero arch, or as complicated as a complete, fully-adjustable aftermarket suspension front and rear. Keep in mind that at the front you will lose suspension travel with a lowered suspension, but it can still be street drivable with quite a low setting. Your limitation here will be the lower bump stop, and a street car should never be run without one. You can modify the stop to gain just a little more travel. At the rear, it is all springs, though you can add spacer/lowering blocks for a low-buck drop.
Big Cam Lope
I have a stock 1979 Dodge D100 Adventurer. I want to add long tube headers, an intake and carburetor. I don't use the truck for anything but cruising, so I want a stupid choppy cam in it. I don't know what the stock heads can handle and I don't want to damage anything. What is the max lift and duration I can run?
John, the limiting factor with a stock 360 is going to be the retainer-to-guide clearance, which usually becomes tight at a little over .500-inch lift. If it's a choppy idle you want, you don't need to max out lift and duration to an insane level. The low compression stock 360 will be pretty unhappy with a really long-duration cam. For what you want, a tight lobe separation of 108 or less, and duration at .050-inch at 230 to 240 degrees is going to lope like a can of rocks. The Mopar Performance 284/.484 will have a radical chop, and the lift is pretty moderate. Competition Cam's Nostalgia/Purple Plus cam 20-671-4 also has lower lift number, but the big duration and narrow lobe separation really creates a lope at idle.
Keep in mind, that you should check the retainer-to-guide clearance, and upgrade the springs to match the cam. You should also check to make sure the exhaust side isn't fitted with exhaust valve rotators as retainers, as these severely limit the lift, and need to be replaced with regular retainers. Finally, the "stupid choppy cam" has its drawbacks in a low compression engine with stock heads. The low end torque will take a big hit, and drivability will be very poor, even with really good tuning. Personally, I would not go with a cam like this for this application, but if it is a rough idle you want, these will do it. Another option is to talk to the folks at Hughes Engines. They have a line of specialty cams that offer a hot street idle, and are sized to offer good performance and sound in low compression engines.
More Stall for Speed
I have a 1973 Dart Swinger with the matching numbers 318. The engine has 302 swirl-port heads, a 340 "resto" cam, an Edelbrock Performer manifold and 600 carb, a Mopar performance ignition, and Hedman headers. The Dart has a 3.55 Sure Grip rear end, and a stock 904 transmission. I was wondering how much a mild converter will help? I am trying to get the car into the high 14's. It currently has run a best 15.2 at 92 mph.
Thanks Ron Wallace
Ron, I can't give you an exact number on e.t. improvement, but a moderate stall converter will defiantly be an advantage on the track. I would advise you not to go overboard however, since the mild cam and small port heads cap the high rpm potential of your combination. It will help the 318 get up into a higher torque range sooner, taking better advantage of the power curve. I'd talk to the converter manufacturer of your choice and step up the stall.
I have a low mileage 5.7 Hemi that was salvaged from a wrecked Chrysler. I bought the engine for my 1970 Duster project, and upgraded it with a Comp XFI 268H cam. It is equipped with the plastic intake manifold with the forward-mounted throttle body. I will run this engine with EFI, and a Holley controller. It will have engine swap headers in the Duster, and I will hook it to an 833 transmission.
My question is regarding the heads. I know these Hemi heads flow really well, as compared to the LA small-block heads. On the other hand, I am wondering if I am leaving some easy power on the table by leaving the heads stock. I would hate to have the engine installed and then decide that I should have done some head work. With the factory intake and conservative cam specs, do you think additional head flow will make a difference?
Mike, as always, the value of the head work depends upon who is doing the work, how far they go, and how much real improvement was achieved. The Gen III Hemi heads respond very well to porting, and that translates to power. I have tested combinations very similar to yours on the dyno, and the fully ported heads were worth considerable power. I would take this additional step now while the engine is out, and save second guessing later.