1500 rebuild

Hi everyone im new here and also to vw .I have just bought a beetle with a 1500 engine it has not been going for over 20 yrs,Its been in storage. I have the engine out and wanted to rebuild it with some performance mods for extra go have no idea were to start eg: barrels ,cyl heads ,cam etc any help would be greatly accepted cheers jason

Welcome Oldtimer

You joined up to the right place, the guys here are really good, none of the bitching you find on other sites.

Why dont you tell us your budget on the build, A Dub engine is the same as any other engine, mods depend on budget. So if you tell us how much you are prepared to spend then the guys here will piont you in the right direction.
Trev

I am no expert but i was at a vw get together recently and was told you cant get parts for the 1500 in particular pistons and rings although i maybe wrong. I was advised it was better to get a 1600 twin port or an even bigger motor.

I am sure the guys here will correct me if i am wrong or at least offer better advice. Good luck with the rebuild

Bearing in mind that I'm not the most experienced expert here, I can give you a general run-down on what I would recommend.

Your first port of call will be to determine exactly what condition your current engine is in. You need to measure the crankshaft end float and check the engine's compression and the condition and clearances of all the bearings. Depending on how good your original crankcase, crank and rods are it may be much better to start with another engine, especially if your crankcase has cracks or is out of spec. Basically, for an engine build with a sensible budget, my recommendation would be to aim towards an essentially stock 1600cc twin-port, with some sort of bigger carburettor than standard and a decent exhaust. If your existing crankcase and bottom-end are in good condition, then you can convert it to 1600cc twin-port by changing the cylinders, pistons, heads and manifolds.

This should get you somewhere in the region of 70hp or more for a sane amount of money. I bought a good running 1600cc twin-port for $800, although if you have to rebuild one then costs could escalate substantially. Most engines will need $300-$500 worth of machining, then a couple of hundred for new bearings, gaskets, etc. If you need to do valves, valve guides and valve seats then this will cost more again. The stock carburettor and manifolds limit performance, so these can be swapped either for a single centre-mount carb or twin carbs. Popular options are Weber IDFs and Dellortos, usually ranging from roughly $500-$1000 for a conversion kit. Headers and sports mufflers can be found used from about $100 or new from $250-$500ish and they will help your engine breathe.

After this, the next port of call would be a big-bore kit, although these can reduce the reliability/longevity of your engine. Once you've gone for a big bore, then you need to start thinking about cams, valve springs and possibly head work if you want more power. As a general rule, the more power that you extract from a Beetle engine, the more money they cost and the shorter they live, so a stockish 1600 with carbs and exhaust is probably the best compromise for a daily driven car.

Waveman,

you have pretty much described what I need to do to my stock 1600 twin port which I intend to do in the next few years. Basically a bigger cam, exhaust and some duel carbys

Thanks guys for your comments,
now so far i have pulled the heads of the bores are really clean with no signs of wear the engine was out the bug when i got it i was told that it wouldn't go so they removed it to overhaul it. So far as it looks i am only thinking something mild along the lines of maybe 1600 barrels and heads a downdraft weber ,cam and exhaust say up to a couple of grand as this is my first go at vw. Ive had quite a few modified jap cars and aussie v8,s having done most of the work myself so not frightened of getting my hands dirty.

I really am thankful any help you guys can give . jason

Well, if you're used to modern engines and Aussie V8s, you will have a lot of things to adapt to with the VW motors! They are a unique engine and have many quirks to learn. They are very simple though, and there are good workshops around to help you. Unfortunately the power figures that you will be getting are significantly lower than those of Japanese and V8 engines! Luckily the Beetle makes up for this with it's low weight.

The first thing to remember is that the magnesium crankcases are very soft and fragile, so be wary of cracks. Places which are likely to crack include between the cylinder bores and around the oil cooler mounts, also check around the engine mounting bolts and generally all over.

The bearing shells are much harder than the case, so uneven crank vibrations can sometimes pound the bearings into the case, making the hole which the bearings sit in go out of round and oversized. It's best to check this with a micrometer or vernier caliper, as this is one of the major factors in whether or not the case can be re-used. If the bearings move around in the case when you pry the flywheel back and forth with a screwdriver, then the case will either need to be line-bored for oversize main bearings or replaced. If there is excessive crank end-play but the bearings remain fixed in the case, then you may just get away with a new set of main bearings, although this is sometimes a topic for debate. My uncle has been building VWs for years, and he reckons that simply replacing the main bearings without machining the case is usually a bad idea, but if you measure it up and the bearing surfaces are all within specs, then I don't see why you couldn't do it. You should of course check that your crank is within specs as well.

Another thing with inspecting a crankcase is to make sure that all of the head studs (and other studs) are sound. There are two types of head stud, 8mm and 10mm diameter. Contrary to simple logic, the 8mm ones are better and will last much longer, because they expand and contract at a similar rate to the crankcase/cylinders/heads when the engine heats up. 10mm ones don't expand enough with heat and will tighten up, making them tend to pull out of the case. If you have any damaged head stud threads, or if you want to change from 10mm down to 8mm, you will need a new set of case savers put in. Case savers are a thread insert, which are usually considered to be better and stronger than simply threading into the case, not just a dodgy fix.