I wanted to add a little oompf to my '78 L48 but I would like to add what I can while keeping it looking stock under the hood. Everything is stock except the Flowmaster exhast.

I recently had it on a dyno,(180 hp and 250 ft/lbs torque at rear wheels), and I was told better numbers than what stock should have been at rear wheels with auto trans.

Does anybody have any good ideas for adding a little more power, (maybe 220 hp-250 hp total), without changing the appearance or busting the bank? Any ideas and/or experiences appreciated.

There'a another thread active about Bang for the Buck ... with lots of good hardware suggestions.

When I built out my 75 L48, I did it to maximize performance in the environment in which I do most of my driving ... meaning below 5500 RPM. And I wanted the car to accelerate off the stoplight like a 67. And idle resonably, and produce ample vacuum. It now does all those things ... and I have no idea of what her actual HP may be.

Equipment profile: Complete Edelbrock Performer Power Package (Heads, Intake, Cam) plus their Q-Jet,water pump and gear drive; Comp roller rockers, MSD ignition and Hedman Hedders, as recommended by Edelbrock; TH400 with shift kit; 3.70 RA; duals into MagnaFlow Turbo XL's. Block is NOM four-bolt.

Thanks for the info. I am not very mechanically inclined, so what would be a reasonable price range to have a shop install new a new cam and heads? What else would need to be added/upgraded if I change the cam and heads?

That depends on what you want out of it. The right cam and heads could mean a lot if you upgrade the intake and exhuast system.

Brian's nuts-on. Without the intake and exhaust, the heads and cam have nothing to work with. If you're doing a piece at a time, conventional wisdom says intake and exhaust are first on the list, followed by cam and heads. FWIW, Edelbrock's tech support guys are really good about coaching on topics like these. Find their e-mail and 800# at www.edelbock.com



There's a fair amount of labor in doing this stuff ... and there are right ways and wrong ways to do most of it. The wrong ways will get you lots of trips on the ramp truck. Shop for capability (i.e. someone who's done this sort of thing on C3's ... lots of times ... and can prove it) and the pricing will be an outcome.




|UPDATED|9/28/2003 8:50:51 AM|/UPDATED|

Personally speaking Barry, if I had a Silver Anniversary like yours I would want it original as possiable. Anything you do other than internal is going to show,ie.performer intake,headers,carb etc. If you want max performance and horsepower (like I did with my 71) you are going to have to let go of its originality. Mine has cam, compression pistons,edelbrock performer low hi-rise, Holley 650cfm offroad racing carb, MSD pro-billett dist, 45,000 vlt. blaster coil, headers, flowmasters, 8.8 plug wires,etc. Anything I do or have done increases HP. I will soon have her dyno-tested, but having been around fast cars for a while I would guess around 450 HP.All I know is all the stock c3 automatics I have driven are not even close to the same class as mine. The downfall, stock is gone. I will e-mail pic of motor if you like, Terry

Thanks for the info. I think that I have decided to keep it all stock except for the Flowmaster exhaust which was already done. It shows too well to disturb and, that is most of the fun of this year vette especially since they never really had that much power to begin with. i think I'll just preserve the history and look for faster options down the road.

Thanks again!

good decision,Barry, 78's are special , especially the pace cars and Silver anniversaries like yours. It looks great and sure turns heads as it is. Speed isn't eveything, just one aspect of owning a Vette. Yours has more meaning and history to worry about better speed.just my $.02, and Colleen's too.

|UPDATED|10/14/2003 7:44:08 PM|/UPDATED|

Before you give up, try lighter advance springs and playing with timing and the carb jetting. 70's emissions motors were very lean and retarded. Going to performance settings will get you a noticible increase in power, especially if you removed the cat. Joe

I have a '78 Silver Anniversary as well. Mine has an L82 engine and I wanted to make the car more responsive, not max power. I added an Edelbrock Performer intake, had the Q-Jet professionally rebuilt, removed the EGR equipment, and replaced the stock exhaust with a true dual exhaust with low restriction mufflers. There is nothing here that can't be put back to stock with little effort since I'm saving all the old parts. The car runs far better. I've also noticed that since I've made these changes, the engine runs about 10 degrees cooler. Why I don't know, but it's OK with me.