Building a Fast and Reliable Engine, cont'd

An 84 stroke could technically be used with stock length cylinders but it is a good idea to go with longer ones with 84, 86, 88, 90 stroke cranks. Unfortunately the only cylinders that come in longer sizes are 94s so I guess you will just have to be satisfied with huge motors like these:

• 84x94= 2332cc
• 86x94= 2387cc
• 88x94= 2443cc
• 90x94= 2500cc

I would keep your rod ratio at 1.67 or slightly more for these bigger motors since a shorter rod ratio gives you more torque at a lower RPM and these motors generally don't need any help in the torque department! Rod ratio is the crank stroke divided into the rod length. Stock VW rod length is 5.39". Porsche length is 5.325" and other popular sizes are 5.5, 5.6, and 5.7. You can order some brand rods in any length. Carillo, Pauter are a few...

One drawback of a long stroke motor is that after 82 mm they become increasingly wider and you must start to trim the engine tin to get it in the engine compartment. You can build your motor around this though. A 78 crank with stock rods or an 82 crank with Porsche length rods coupled with any size stroker piston will fit well into even an early 1200 engine compartment. Or you could just start snipping tin.

Now that I've gone over what it takes to build a larger displacement motor I will get into the "state of tune". Allot of Cal Look VWs these days are sporting huge motors with giant cams and heads. These engines can put out upwards of 200 HP on 92 octane gas. That's about 1.5 horsepower per cubic inch. In comparison, a 406 ci V8 would have to put out over 600 HP to make the same HP per cubic inch as these VW motors do. These motors are impressive to say the least. But they aren't the best choice for a nice driving, fast VW. On the other hand I see people putting together a new motor with such conservative parts that it seems a waste to me. Ultra low compression ratios, tiny cams and worst of all some advertiser's lame non-ported out of the box heads! Money spent on head porting is never a waste. Well-ported heads will make any motor run better. Sometimes allot better. I believe that the best street motor is a big motor with a medium state of tune. An 82 x94 is just about the biggest motor u can assemble with stock rods. Combined with a set of 40x 37.5 non-welded, fully ported VW heads and a 295dur. x 500 lift cam, a set of 48s (not IDAs) and a 1 5/8s exhaust.

You can have a motor that doesn't cost a fortune to build, will last (as long as you take care of it) and will haul ass! It will also get decent gas mileage and drive like a dream. This motor will pull at low RPMS as well as high and you won't need to have close ratio gears in your transmission because it will pull with stock gearing, no problem. In fact, it will run the quarter mile in three gears and you still have 4th gear for the freeway. You can also use this same motor in a bus but you will have to raise the gear ratios to make it drivable - unless you want your bus to run 14s in the quarter! I suggest a late model 4.86 or 4.57 R&P along with some larger diameter rear tires for bus applications.

A motor like this will pull from 3500 to 7000 with the right heads. The same motor size but with aftermarket or welded VW heads and a 320 duration cam will usually only pull from 5500 to7500. A much smaller RPM range. That's why they need closer ratio gearing and a 5 speed to drive on the freeway. Of course they are frightfully fast too! Huge motors with huge cams can be driven around with no real problems although they will need valve jobs more often. It's just that you have to be in the right gear to make it go and it will not get very good gas mileage. You have to ask yourself do I want to sacrifice so much for a 12 in the quarter instead of a 13? Just look in the magazines under new car specs. and see how many cars run 13s in the quarter. Not many and you usually won't see one driving around anyhow. But to each his own.

I will take a motor with a middle state of tune every time but some of my friends just want the most power no matter what the cost and they like high state of tune motors. The thing is if I'm next to them and they're not at 5500 RPM when we jump on it, I will leave them in the dust!