Iron fists....in Velvet gloves

Had some people ask me how could they get big power out of their musclecars and still look totally stock?  Here's the best ways to do it without breaking the bank. # 1. More cubes. The old saying-"There's no substitute for cubic inches, except cubic dollars" is still true. And no one is saying you have to go buy a whole other engine. Eagle, Scat, Lunati, and many other companies offer stroker cranks and / or rotating assemblys ( that include the rods and pistons, and rings&bearings ) for most popular engines. There are kits to turn a 350 Chevy into a 383, a 351W Ford into a 392, a 360 Mopar into a 408, a 400 Mopar into a 451 and a 400 Pontiac into a 455. All other factors being equal, the larger engine will always make more power and torque with the same equipment. # 2. More compression. It's not like the old days where you could build an 11:1 or 12:1 motor and run it on the street because your local Chevron station had 100 octane "Custom Supreme" for 39 cents a gallon. However, even with only 89 or 91 octane gas available today for 4 bucks a gallon, you can get away with about 9.2:1-9.5:1 with Iron heads pretty easily, and if your cooling system, and fuel system and ignition is perfect, you can sometimes get away with 10:1. (Aluminum heads can tolerate more because they dissipate heat better, but then you wouldn't look stock, would you? ). In most cases, you don't have to change pistons-you can just change the heads. For example the average 350 Chevy built from 1971-86 has about 8.2:1 compression, with 76cc combustion chamber heads. Switching to 64cc heads would up that one full point to 9.2:1. Using 58cc 305 heads would up that to about 9.6:1. Switching from the stock 83cc heads that come on '73 and later 350 / 403 Olds engines to the 70cc heads of the 68-72 350s will bump compression a full point from 8:1 to 9:1. ( You'll have to re-tap the bolt holes on '75 and later blocks, but Mondello Performance sells a kit for this ) Most 400 and 455 Pontiacs built after 1970 have compression ratios around 8.0:1. Some 75 and later models had 7.6:1 ratios! This was achieved with combustion chamber sizes of about 90cc on a 350 / 400 and about 111cc on a 455. Switching to 72-75cc heads on a 400 will raise the compression to about 9.5:1. Switching to 87-90cc heads on a 455 will do the same. ( It's quite popular to put 350 or 400 heads on a 455 for this quick boost.) The 72cc heads would bolt on to a 455, but the compression ratio would be about 11.5:1 which is much too high for iron heads and pump gas. The same goes for many Ford and Mopar engines as well. Consult books about each individual engine line for what years and casting numbers to look for. # 3. Cylinder head airflow. Especially if your going to change the heads anyway in looking for more compression, you might as well get a set that flows better as well. A couple of good examples-1996 and later small-block Chevy "Vortec" heads will bolt onto earlier blocks, and are worth 30 or 40 hp. Their 64cc chambers will give you the compression bump over stock 76cc heads, and they flow way better. You'll have to get a Vortec-style intake, but Edelbrock, Weiand, Holley, and even GMPP have you covered. (Most are aluminum, but if you paint them the stock color, 99% of people won't notice.) Plus, most of us will accept the HUGE power gain for not being totally stock looking. The same goes for small-block Mopars. 1992 and later 318 and 360 "Magnum" heads flow better than any factory head and many aftermarket ones, and they will bolt onto '91 and earlier blocks. Same thing-you'll need a "Magnum" style intake manifold, but Edelbrock and Mopar Performance have you covered. 1976-79 "6X" Pontiac heads flow better than any factory head except the vaunted and rare 1969-72 RAIV / 455HO heads. Again-check "How to Hot Rod" books for your particular engine line; most of these will tell you what casting numbers interchange and what they flow. # 4. Cams. No one can tell what cam your running by just looking at the engine. And if you've increased the cubes and compression, your going to need a bigger cam anyway. Edelbrock, Crane, Lunati, Competition Cams, etc-all offer performance cams for most engines and their catalogs will give you solid advice on what engine size, carb, compression, gear ratio, converter stall speed etc, to use. If you follow their guidelines you won't go wrong. # 5. Induction. There are several ways to look stock and still improve here. For example-GMPP makes an exact replica of the original Z/28 / LT1 manifold ( That Smokey Yunick says was the best SBC manifold ever made-it's good from idle-7,200 rpm ) in cast-iron. This was done for circle-track and drag racing classes where the rules say you have to run an iron manifold. However it will work on the street just as good as an Edelbrock Performer RPM, it'll just add about 30 lbs to the engine compared to an aluminum intake. 1975-79 Pontiacs had a VERY restrictive intake-the EGR valve actually protrudes into the the throttle opening. This really limits power above 4,000 rpm. It's so bad-that you can't even bolt on a spread-bore Holley carb-the throttle blades hang up and won't open fully. Most people just trash them and replace them with an Edelbrock Peformer. However-if you want to look stock-the 1967-74 factory iron Q-jet intakes are quite good up to about 5,800 rpm. This manifold is about equal to the Edelbrock Performer.  In fact-Popular Hot Rodding tested a bunch of aftermarket intakes on a 400 Pontiac several years ago. Only the Edelbrock Torker II showed a noticable gain of 20-25 hp-above 4,500 rpm. Some of the others actually showed a loss. Since then Edelbrock has come out with a Performer RPM Pontiac manifold that is supposedly worth 25 hp and 30 lbs ft of torque over the Performer or the good factory one, but they won't fit under a Trans-Am hood, and they don't look stock!! I could go on and list other examples, but you get the point. And you can always have a factory iron intake port-matched to the gasket and extrude-honed for increased airflow. You can usually get away with a 1/2 inch or 1 inch spacer under the carb for a few extra top-end ponies, although you'll have to richen the carb jetting. #6. Exhaust. Obviously headers will give any engine a big boost, but they definitely don't look stock, and unlike heads and intakes that can be painted or have numbers and logos ground off, there's no way to make headers look like stock exhaust manifolds. However-all is not lost. The main thing is to use at least 2 1/4 inch pipe ( preferably 2 1/2" or 3" on engines over 400 cubes ) some low-restriction "Turbo" style mufflers and a balance tube or x-pipe between the two pipes to maximize flow. And, again-read up on what factory exhaust manifolds flow best. A couple examples-for years small-block Chevy "Hobby stock" and "Street Stock" circle track racers have used the "Ram's Horn" exhaust manifolds-because the class rules say no headers allowed, and these flow better than other stock manifolds. R.A.R.E., NPD, Year one, and others offer reproduction exhaust manifolds for just about anything. If you have a Pontiac with D-port heads ( only the RAIV / 455HO / 455SD's had round ports ) the Ram Air III or "long branch" factory or repro iron manifolds flow almost as good as a set of "shorty" headers. And they can be ported and extrude-honed as well-as can manifolds for Fords, Mopars etc-you get the picture. # 7. Mechanical advantage. Most '70's and 80's cars because of tightening fuel economy and emissions laws have high ( low numeric ) gearing like 2.56:1 or 2.73:1. ( Even 5-speed "5.0" Mustangs came with only 2.73 or 3.08s from the factory ) Swapping this Salt-Flats gearing for something in the 3.23:1 to 3.73:1 range will give you a huge boost in acceleration without hurting gas mileage or freeway drivability too much. If you have an automatic transmission-"Shift Improver" kits from B&M and TransGo will drastically improve performance. A slightly higher-than-stock stall speed torque converter is a great "stealth" modification to get quicker acceleration. Just don't go overboard. For example-even if you have a 1993-2002 Z/28 Camaro or Firebird Trans Am with a computer-controlled LT1 / LS1 engineand 4L60E overdrive automatic-you can use a converter with up to 3,300 rpm stall speed. ( Anything over that and the computer thinks the trans is slipping and burning up and goes into limp-home mode ). However, computer-controlled or not, you'd have to have an awful radical setup to actually NEED a conveter with a higher stall speed than 3,300 rpm!! # 8. Ignition. Petronix and several other companies offer kits to convert point-type distributors to electronic ignition, and still use a stock-looking cap. Even if you want to stay with a point-type ignition-Accel and Mallory offer hi-performance point type distributors, ( just put a black cap on them ) and they sell point sets, and re-curve kits for stock ones. You can paint a 50,000 volt Accel, Mallory or MSD coil black, and no one can tell the difference between it and a crappy parts store one that doesn't even put out 25! If you have a 1975 and later GM or Ford product or 1972 and later Chrysler with factory electronic ignition, Accel and MSD offer performance upgrades-curve kits, modules, vacuum advances, higher-output coils, etc that will drastically improve performance, and drivability. So get to work and build a badass stock-looking "sleeper"!  Mastermind