Hey, I have a 68 Riviera with an 430 in it. I think the pre owners don't have any care of the car. So I want to rebuild the engine by myself this year. As I need to import the whole parts (I live in Germany, need to pay 19% tax plus 10% customs plus shipping) I don't want to spend tooo much money. BUT if there is any chance to get some more power for just a little bit more money I will get it. Actual I plan to build some 2,5 inch stainless exhaust without headers. Also I will try to port the stock intake and heads, rebuild my quadrajet and buy a new cam. As this will be my first engine to rebuild I need your help. What parts should I need and where to get? What parts would you choose to get a solid engine for the future if there is any need of more power Thank you. Sebastian
To rebuild an engine, you need to take it apart, measure everything, and THEN, you decide what you need based on those measurements. Until you do that, no one knows what you need. If the cylinders need to be over bored, you need new pistons to start. If the crank needs to be turned, you need different bearings. If you can effectively port the cylinder heads and intake, that will be you best bang for the buck.
1. BEFORE you disassemble the engine with the intention of rebuilding, you'll need to know who can bore the cylinders, grind the crankshaft, plane the deck surfaces of the block and heads. Who can install cam bearings? WHERE would you have that machine work done locally? Who would you trust to get the metric/english measurement conversions correctly? 2. Unless you KNOW the engine has real problems, get the ignition advance, and carburetor tune as close as you can. Maybe replace the timing chain if the original is worn. Verify that the rocker arms and rocker shafts are not worn, replace as needed. Everything you can do to make the engine run better that doesn't involve major disassembly will help you, and it won't be "everything at once" which tends to be rough on a novice. Everyone I know, wrecked the first engine they overhauled by themselves. Including me. My 283 Chevy lasted about eight months after the overhaul.
The 1968 version of the 430 was different than the 1967 version, since there were new emissions requirements in 1968. If your engine has high miles and runs like it has a lot of wear, then rebuilding it would be a good idea. If the original engine still runs fairly well, then you may not need to do a full rebuild. Like a lot of members can attest: sometimes an expensive rebuild/upgrade to an existing cast-iron engine may not give you the performance improvements you are expecting. I'd start with performing a compression and leak-down test of the cylinders which will help determine if you have worn rings and or burned valve seats. If either one shows, then you should consider a top-end rebuild to clean up the valve train and/or re-hone cylinders and replace rings/pistons. If you pull the oil pan, changing the main & rod bearings can also be performed. At a minimum, doing a top-end rebuild (tear down heads, re-grind valve seats, change lifters) and upgrading the ignition system and carburetor with correct parts can go a long way to improving performance. Just keep in mind: there will be limiting factors to your power improvements. The Riviera is a 4400 lb full-size vehicle, and unless you replace all of that metal with carbon-fiber, it is a lot of mass to get moving. I'd check craigslist and ebay for sellers of 430 engine parts, especially if you can find spare heads, rochester 4MV carbs & exhaust manifolds.
