More Power

[jeffandgayle]

Hi,Glad to find a site dedicated to type 4 I will be asking a lot of questions as I purchased a type 4 engine earlier this year, I'm running it in my manx style buggy. First of its the engine code GE 67hp I noticed the GC at 88hp and the GB at100hp can you raise the hp by installing these heads on the GE or are there aftermarket heads to do the equivalent and is it because of the heads the difference in hp. Thanks Jeff

[Bleyseng]

Yes, you can swap all the Type 4 parts around to improve your hp. A GC engine code is from a 75-76 914 2.0l (88hp)with air injection, a GB is a European engine code 2.0l. A very common engine is the 95hp 73-74 914 2.0l GA engine (95hp). I am not sure what a GE engine code is, must be a bus. I am sure you could put the 2.0l 914 heads on to gain some hp but you have a lower compression ratio than the 914's (7.5:1 to 8:1). The 914 2.0l heads are designed for more flow and require the use of the 2.0l engine tin also as the plugs are located differently too. Are you staying with FI or going with carbs?? the list of options goes on and on. Also the exhaust is important to get the hp figures,using a bus exhaust will get you bus hp. Headers is probably your best be unless you want heat! Geoff

[jeffandgayle]

Yes, we are running a carburetor, Weber Progressive. For now. Was thinking of getting some dual Weber 44's depending on advice. Looks like people are running 40's mostly. Was going to get Mark Stephens unshrouded heads. Good thing I didn't order. Who else carries similar performance heads? Current valve sizes are 37.5mm X 33mm. That was because it was fuel injected. What would be a good valve size for Weber 44's? Thanks... Jeff


[This message has been edited by jeffandgayle (edited 06-27-2000).]

[tuna]

The changes in the horsepower isn't necessarily in the heads. There were other factors, such as compression ratio (which the 914 was higher), emissions system (the GEs had more of it than the earlier 2.0s like the GB and GC), and other related things.

I really don't think you'd be pleased with the power gained with the 914 2.0 heads. They do flow well (better than your current heads for sure), but the heads aren't your restriction. The restriction on your engine right now is the carb/manifold. The progressive weber is good for a low RPM stock engine, but with a buggy you'll want more (I know I do with my buggy).

If you have a stock cam, I'd suspect that 44s would be overcarbing it. The 40s would be better suited to the stock cam in a pretty much stock engine. Also, don't go with large valves until you get more carb and exhaust to handle the increase flow.

I suspect that the heads you have are also the "Vanagon exhaust port" heads. They are rectangular and are incompatible with the aftermarket exhausts I've seen. You will have to keep this in mind as you go about building this engine.

In order to get the most out of your engine the first, have a roadmap of what you expect out of the
engine and how much work/money you want to put in it. Let us know how much you are willing to invest into this engine and what you want out of it. There are a lot of experienced people here who can help you in your journey in to Type 4s.

Tuna

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If you want to learn more about the Type 4 engine, check out my website at
http://www.tunacan.net/t4/

[jeffandgayle]

I guess I'm looking to invest $1000 - $1500 was hoping for a 96mm bore kit with some decent heads, i use to see at mshp p/c and heads for around $600 stage 1 I believe, simple bolt on, I'm not confident enough yet to split the case, do you have to split to replace cam? Looks like solid lifters are preferred. So i'll probably buy the duel 40's duels its just that the 44's are only 10 bucks more is why I was asking about them and tear into it after the season which we mostly run at Silver Lake Sand Dunes in Michigan. Know of any similar or a company that puts together p/c and heads like mshp? Thanks Jeff

[Dave_Darling]

GA = 914/2.0 73-74 ; 7.6:1 CR, 95 HP.
GB = 914/2.0 Euro ; 8.0:1 CR, 100 HP.
GC = 914/2.0 75-76 ; 7.6:1 CR, 88 HP.

The 75-76 914s had an awful wrap-around exhaust, plus a smog pump and catalytic converter. Those are responsible for the lost 7 HP.

I *think* that the Bus engines were even lower compression, with a deeper dish in the pistons. They tended to be set up with low-end torque more in mind than overall power--and even the 914 motor was pretty torquey! The 73-74 US version makes 105 lb-ft all the way from 2500 RPM to 4500 RPM, with a peak of 108 lb-ft at 3500!!

The Weber 44s are definitely more carb than a stock 2.0 motor needs. If you are going with a wild cam and other mods for top-end power, the 44s will work well. But on a stock or close to stock motor, the 40s are generally preferred.

Actually, I myself prefer FI. But that's another argument.

--DD