How to get maximum performance from your Musclecar....Even if it's bone-stock...

I talk to a lot of people who don't want to modify their musclecars, but complain that they don't run as well as they'd like, or that they got their doors blown off by a supposedly "slower" car. There are several causes of this problem. I'll list each one, and tell you how to fix them. # 1. Do a compression test. Even an 8:1 "smog" motor will have 120-130 lbs of compression. Higher compression engines may have 150-175 lbs. ( Ultra-high compression engines like a 12.5:1 L88 Chevy can have as much as 220 ). The readings should be consistent for all 8 cylinders-within 5-10 lbs of each other. If one or more cylinders reads 80-90 lbs you could have a blown head gasket or bad piston rings. You'd be amazed at the number of musclecars running around on 6 or 7 cylinders. # 2. No high rpm power. I'm not talking 7 or 8,000 rpm; many cars don't have the valvetrain or bottem end strength for that. But even a 318 Dodge with a 2 barrel carb and 150,000 miles on it will rev to 5,000 rpm or so. If your car starts popping or backfiring through the carb over 3,500 rpm, or won't rev past 4,000 or 4,500-you could have a flat cam, or broken valvesprings, or a burned valve on one or more cylinders. You'd be amazed at the number of cars I see with $5,000 paint jobs that can't pull 5,000 rpm in low gear. # 3. Bad tuning. This one is the most rampant. Even on a stone-stock engine, bad tuning can cost you as much as 50 hp. You'd be appalled at the number of cars I see with $5,000 paint jobs and $2,000 worth of wheels and tires, and the vacuum advance on the distributor is unplugged or inoperable, the timing is way too slow or way too advanced,the carb is way too rich or too lean, the points are closing up,it has one or more bad plug wires,an exhaust leak and the owner can't tell you the last time he changed the plugs!! Trust me-you'll be amazed at the improvement in performance you get just by installing a new distributor cap and rotor, points and condenser, and plugs and wires, and setting the timing to the factory recommended degrees. # 4. Bad carburators. I don't mean jetted too rich or too lean-that's an easy fix. But I see dozens of cars with the floats sinking,bad accelerator pumps,warped throttle shafts,or baseplates,and massive vacuum leaks. You have to realize-the car is 40 or 50 years old. Parts wear out. If you have to have a numbers-matching carb for concours shows or if you want to sell the car someday to someone really anal-here's what to do to make it run properly and enjoy it. Put the old carb in a box in your garage, and call Summitt Racing and get a new one. For example if you have a '70 Z/28 or Boss 302-you can buy brand-new 3310 780 cfm Holleys with GM or Ford linkage. I know the Pure Stock drags and many Concours show organizations are allowing the carb to be the original "Type"-in other words-the Quadrajet on your '68 GTO does not have to have 1967 or 68 date codes on it-it can be a Jet Performance or Carb Shop rebuilt unit. This good for cars with carbs that are no longer in production. If your a Mopar guy you can't buy a new Carter AVS 4bbl, but Edelbrock sells AVS carbs that look identical to the old ones, and work flawlessly and are available in 650 and 800 cfm versions-the old factory ones only flowed about 585 cfm. Ditto for Cars that originally had Carter AFBs-early '60s 'Vettes, '64-66 GTOs, and of course 409 Chevys, 421 Pontiacs and 426 Hemis. The Edelbrock "Performer" series is an exact replica of the AFB and is available in 600, 750 and 800 cfm versions. If your a Ford guy-and your car originally had a Holley on it your in luck-the original "type" rule again-you can put a 750 Holley on your GT350 or 428CJ Mustang- no ones going to ding you because it isn't a 715 or 735 cfm version with 1960s date codes. If you have the misfortune to have an Autolite 4100 or 4300 4bbl on your Ford, you'll just have to put it in a box, use a Holley or Edelbrock to make the car run properly and use the old one for shows, if it is a show car. But no one offers new or rebuilt Autolite carbs, and they were HORRIBLE when they were new. My dad was a Ford master tech in the early '70's and they had massive problems brand-new-they wouldn't idle, wouldn't start in hot or cold weather, had no power, and got crappy gas mileage. If you had a Mustang with a 351C or a T-Bird or LTD with a 429 or 460 and you bitched hard enough the dealers would install a 6619 600 cfm Holley and warranty it. When you install the new carb make sure the throttle linkage doesn't stick and opens all the way, and if you have an automatic trans, make sure the kickdown linkage is hooked up properly. This is a big one-I see cars all the time that the throttle will only open halfway or 3/4 of the way. # 5. Neglected transmissions. I see cars all the time with slipping clutches, or shifters that hang up between gears, or pop out of gear for no reason. Hurst offers a rebuild program-you can send in your old shifter and they'll re-furbish it and put new bushings and shift rods on it. I see automatic cars all the time that are running around 1 or 2 qts low on fluid, or haven't had the fluid changed in years,the vacuum modulator is unplugged or not working. Chane the fluid at least once every two years or 25,000 miles. Make sure the modulator is working, and install a B&M or TransGo shift improver kit. You'd be amazed at how well a car runs when everything is in proper tune and working the way it should. Mastermind