VW 1600 heads

Well I made a deal on a 74 VW Super Beetle with a 1600cc engine. I plan on building the engine and putting a turbo on it. My question is, what's the absolute biggest bore I can put in the stock heads?

I think 92mm is getting close. I wouldn't go to 94 without getting something aftermarket.

Well you could machine out the cylinders to have paper thin walls whose life could be measured with a stopwatch. So the question I have is: What is your real goal with this engine and transmission?

and more importantly...Whats your budget and how long do you expect the engine to last?

In reply to Ojala: I haven't really got a budget, more of a goal. And I'd like it to be reliable enough to drive about 50 miles to the drag strip on occasion but also have around 225-250 horses. If that can be done with stock heads. I was planning on getting forged internals for it and all that.

DCharger68 wrote: have around 225-250 horses. If that can be done with stock heads.

Not likely to happen. 225-250 horse is more likely to happen with a mild stroker motor (+turbo). I wouldn't boost on 94's, I'd lean towards thick wall 92's or 90.5's. Plus, if you are throwing all that money into the bottom end, why not get a set of CB's heads?

You could probably piece together a turbo kit pretty cheap and bolt it onto the stock engine. Don't expect it to last long or run that well. But if this is a weekend toy that gets driven only occasionally, whats the harm?

I wouldn't get attached to the idea of stock anything with those power goals for a reliable engine though. Good VW heads are pretty cheap so I wouldn't get hung up on the idea of stock heads. If you aren't super familiar with building vw engines it can help to hit the easy button and buy a full engine kit to simplify the whole process.

$5500-$6000 would buy you a N/A engine that would make that kind of power pretty reliably.

Do you even need that much hp to pull the front tires off the ground?

ebonyandivory wrote: Do you even need that much hp to pull the front tires off the ground?

No. Just to spank on a buddy's Iroc Z

With those goals Subaru power is gonna be more economical.

suby or even type 4 power.. just be sure to use a 2.0 from a 914 or a 912.. not from a bus

I have a buddy who does a lot of head work for VW's and does some drag racing. I posed your question to him (but for some reason I thought you wanted an NA motor) and this is what he said:

Shaun McCarthy said: Go 1914cc or bigger. 69x94 with good heads and med cam. Jerry's engine should be able to take an old stock IROK:) Dual 44 Webers or 48's idf or ida's 9.5 to 1 comp. If he is not driving this car to work he can step up the cam and comp. A close ratio trans really help to in the 1/4 mile and with heavy cars.

The "Jerry" he refers to has a 1776cc with a few modifications (which mods I'm not sure)

Good luck with your build man

You really can't get that kind of reliable horsepower from stock castings.

For numbers like that you'll need proprietary big valve ported heads, along with a whole lot of other stuff!

Essentially you'll end up with an engine with only a small handful of genuine VW parts left in it.

mad_machine wrote: suby or even type 4 power.. just be sure to use a 2.0 from a 914 or a 912.. not from a bus

912E, to be precise. 912 without the E is an entirely different and much more expensive engine.

If/when you really get serious, just hit these two sites:

http://www.shoptalkforums.com/

http://www.thesamba.com/vw/

Click around on the performance/engine forums and ask the members to design you an engine to meet your demands. You'll find out EXACTLY what is required ! Some of the best builders/racers in the world frequent both sites and are happy to help. Be specific as to what you really want; a turbo engine can't be converted back to NA by just removing the turbo, a Type IV is nothing like a Type I, be precise and don't wander.

Nothing worse than three pages of how to get the most out of stock head castings and then having the OP decide that he wants some info on a pair of Mag-44s that his friend just dropped off. You've got the same crap going on here, starting with stock 1600 heads on a Super Beetle and traveling past Subaru transplants all the way to Porsche 912s. This kinda stuff is a waste of time and knowledge.

good point.. but I just do not see a 1600 based engine giving him what he wants and being able to survive even an occasional trip to and from the strip on it's own power. that is why I suggested he start with the larger and more robust Type 4 engine