i need some help on my car i want to keep it all original wich it is and only 78,000 miles on it but i want to get some horsepower out of it and tourgue but i dont want to ruin the originality of it
If you want it to visually appear original, yet increase power, then you're looking at changes like heads, cam, torque convertor, rear gears, good 2.5" mandrel exhaust system, ported stock exhaust manifolds. Visually it would appear the same, but mechanically you would add good power, plus the gears can put it in the best useable range.
how much would that cost and im just a 16 year old with a few dollars you have to understand haha what out of all of that would be the best thing to start with and give me the msot for my money
NICE RIDE love the boat tails... do what steve said. Exhaust and cam will liven it up quite a bit. some mild port work on the heads and exhaust manifolds would help a lot more. Nate
That is a nice Riv! If you're limited on funds, the best places to start would be the ones that would show you the most immediate seat of the pants improvement. Find out what rear gears it has and what is available (you'll want to talk to the other Riv owners for that info). A "non-exact" way to figure out your gear ratio, without pulling the cover is as follows: Get a buddy (sister, brother, mom, etc...), jack up the rear of the Riv at the rear end. Put jackstands under the axle tubes on each side, and block the front tires (safety first!). You'll want it high enough that you can spin the tires and be under neath where the driveshaft meets the differential. Put the car in neutral so that the driveshaft will spin along with the tires. Make a little mark on the driveshaft that will be easy to watch while underneath. Have your helper make a mark on the side of one rear tire at a spot that they can remember (straight up, straight down, etc...). Have your helper slowly make one complete rotation of the tire. At the same time, count how many times the axle turns using your mark. If it makes approximately 3 full rotations, then you're gear ration is around 3.00:1 (or whatever was available in that car - 3.08?). If it makes about 3 and 1/4 turns, then it's around 3.23:1, etc... At the same time, note whether the tire on the other side of the car from your helper is turning in the same direction or opposite direction of the tire he turns. If they go the same way, then you very likely have a posi rear. If they turn in opposite directions, then it's an open rear (one wheel peel). By replacing the gears with lower gears (numerically higher), you will feel a better seat of the pants when accelerating. It will decrease your top speed, but even in the 1/4 mile you aren't going to be seeing over 110 mph likely. That being said, I have no idea what is available for the Riv's for rear gears. But, this is the place to find out!!! Good luck [insert name here],
Another good thing to do is put a quality 2.5" mandrel bent exhaust system on. The mandrel bends eliminate the kinking inside the pipe when the pipe is bent. These kinks effectively reduce the inside diameter of the pipe. They also allow for a smoother flow of exhaust through the bends and turns. An X-pipe is also a great way to keep from impeding flow. It allows the unequal pulses coming from each side of the dual exhaust pipes to cross each other. This causes a scavenging effect that "pulls" the exhaust from the alternate side pipes. The X-pipe goes in front of the mufflers. Add a set of low restriction mufflers, and full tail pipes out the end. Walker dynomax 17749 - Hemi Super Turbo long case mufflers are my personal favorites. They have some of the lowest restriction without the increase in noise. I've had them on my 72 GS350 back in the late 80's, my 71 GS455 that I sold a year ago, and they're going on my 72 Skylark Custom455 once I get a motor in it.
I agree. The seat of your pants will feel the addition of a 342 rear. You may feel slight gains with the exhaust, but it will be a must for the future if you plan on doing more to the engine. A better ignition system will help a little too and is not too expensive to fix. After all these mods, I would start saving money and find another 455 engine to work on as your funds come in. Start with a good bottom end with good compression, then top it off with a nice set of heads and intake along with performance cam. You could still be driving the car over this period and enyoying it. Swap engines when finished and put that low mileage original numbers engine on a stand in the garage. You might want it back in there one day and it will not be blown to bits.
As far as gears go, you are actually screwed, hate to say it but if factory then you have a 9 3/8 rear which is impossible to find ( well close to, and a small fortune) If it is an open rear you have 2.93 gears, if it's a posi then they're 3.42. It mainly depends on the budget you have to work with, and how far you want to go. Personally I'm happy with the performance of my Riv, If I could just get a posi (for real cheap) I'd be set.
Welcome! Nice Riv. Did you or the previous owner get a used driver's side door? It looks like it in the pic. ______________ Rob 1972 Riviera
