big type 4 experiences Options

[cdn9144]

I am looking to build a big displacement type 4 for my 914, and I want to hear from people that have driven a 914 w/ a big "4" . I am looking to build something around 2500-2700cc. Any experiences good or bad would be helpful.
THanks
Lorne

[Jake Raby]

An engine that large is not needed by many people....Trust me.

So many times I see huge engines being built and too many corners being cut. The size of the engines does NOT DICTATE THE POWER IT WILL MAKE! It also does not necessarily dictate HOW LONG IT WILL LAST!

To do a Type IV larger than a 2316cc combo in my professional opinion REQUIRES the use of a set of Nickies cylinders, extensively worked heads, and a combination that will set all the components in motion as efficienly as possible. The stock Type IV head is very tricky to configure an engine around and honestly after 2316ccc you are really creating alot of work to gain efficiency. The stock cylinder heads are very restrictive on the exhaust side and they are most of the time may too modified on the intake side by novice builders and that makes things WORSE!

As amatter of fact after 2316cc the cylinder heads are pretty much maxxed out and all the added displacement simply MOVES THE POWERBAND LOWER. It does not make more power without figuring out a way to trick the engine into thinking it jas more head than it really has! (Thats where odd cams come into play and complicate things drastically)

Look into a 2270 or 2316cc engine done right with the powerband that you want. Done right you will attain 140-190 BHP and a total daily driver that idles as smooth as stock and pulls hard straight to redline. The engine will be simpler to buikld and you won't hit problems that will simply make you give up.

Build it too big, or cut corners and you'll have every possible problem on earth. The main problem with Novice TIV builders is going too big on the engine. The power in these engines is in the combo, NOT THE DISPLACEMENT!

Thats why my 2270 makes more usable power than my competitors 2615!!!! Dyno proven! (and mine is still alive and theirs has been torn down 7 times to repair head leaks and a slung rod!)

Build for efficiency and everything else will magically appear... The only hard part about that is the finding the efficiency is not easy! Remember, The bigger it is the harder it is to find the efficiency... Huge pistons and long strokes create alot of friction and drag- Thats hard to overcome. There is a possibility of more power by adding them but the motoring HP is increased so gains are not huge.

I have seen engine projects get started out with huge intentions and get sold on ebay because the builder made rash decisions and got in over his head. A customer of mine spent 10,000 bucks before he finally sold everything and paid me to build it for him!

Keep it smaller, keep it simple, and keep it together while retaining your sanity. The "Big Boys" are even a challenge for me and these engines are all I live for.