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30-50% increase in power?
landfall - July 19th, 2014 at 11:08 AM

I have an oil leak in my 1976 DP 1600 bug.

If I am going to go to the trouble of removing the engine to fix it and fir the dual ICT's then I might as well consider doing it up a bit.

Not an experienced VDubber so looking for a little advice.

I would like a little more performance, good reliability for a fun machine, not a daily driver.

What parts should I be looking at for this performance?

I have read and reread the forums, purchased the book on building VW engines, etc.

If I get a list together now, I can start collecting the parts needed at a economic pace.

Thanks.

Ken


modnrod - July 19th, 2014 at 12:34 PM

You don't need to go over the top with expensive parts to get a remarkable difference.
I have had 1641cc of fire-breathing dakdak push รก Beetle to high-15s easily, while using stock cam, stock inlet manifold, and ported stock heads, all going through a stock 1300 gearbox. Your twin ICTs would be a bit better again.

The easy way is to bump displacement with a big-bore kit. Whatever size you rekn you need, try to pick a kit with thick barrels, like 88mm thickwall or 92mm thickwall. 88s will allow you to leave your case untouched if your bottom end is fine, 92s will need machining, then bearings, then set up time, etc. IF you need to split the case then change the cam for better performance, if not then use 1.4 rockers on the untouched stocker.

The heads are the key. It isn't wasted money to spend $1000 on good heads for a stock motor, the difference is astonishing and through the whole powerband, not just the top where you hardly ever go.

A stock motor on a dyno reels out mid-40HP roughly. A 88mm thickwall for 1679cc with mildly ported stock heads (L3s? CB 044 Super Mag? Pro pocket ported?), 1.4 rockers on a stock cam, 8:1 compression, 4-1 exhaust or Vintage Speed, and your twin ICTs will crank out around 60-70HP all day.

Good fun to plan all this stuff! :smirk:


Doug Sweetman - July 19th, 2014 at 12:43 PM

Good recipe and advice :)


Bizarre - July 19th, 2014 at 01:05 PM

some good reading here

http://www.aircooled.net/vw-performance/ 


landfall - July 19th, 2014 at 03:31 PM

Thanks for the advice modnrod.

Could I please have your thoughts on a counterweight crank and balancing?

Although I DO like the idea of not splitting the case. At he moment I am in unchartered territory like a lot of other owners I suppose. The car appears to have oil leaking from under the barrels and from the top also on cylinder number 2, weeping on number 1.

The engine has definitely been worked on, but how good a job????

Car runs OK, does not use oil to any worrying degree.

So I am not sure which way to jump. If it's not broke, why fix it?

But I do like your suggestions.

Ken


Bizarre - July 19th, 2014 at 05:27 PM

balancing is essential for a "proper" job

CW crank is for engines that rev above 6k

You can run to say 80 RWHP with a BALANCED stock crank

80 RWHP is like sub 9 sec 0-100...... fast.


landfall - July 19th, 2014 at 05:39 PM

Bizarre,

Totally agree, I have always liked a balanced engine, just seems to make sense.

What are your thoughts of lightening the flywheel? The aircooled site recommends this mod.

Big money saved by not having to go the counterbalanced route.

Thanks for the thoughts thus far, really becoming more practical, after all this is a bug with a seventy year old driver:lol:

Ken


Bizarre - July 19th, 2014 at 05:57 PM

I am against lightened flywheel

Makes the engine rev faster - to the detriment of torque


Bizarre - July 19th, 2014 at 05:59 PM

as you say - it is not really broke

I would leave as is, and save for a really good daily - say a well built 1916

Buy your parts wisely and it is not that dear


landfall - July 19th, 2014 at 06:14 PM

Thanks,

I will compile a parts list shortly and let members peruse it and point me in the right direction.
That way I can buy bits and pieces while it is going OK and be ready when I want to tackle the issues.

Ken


Bizarre - July 19th, 2014 at 06:41 PM

That's the idea

:tu::tu::tu:


landfall - July 19th, 2014 at 07:18 PM

OK, thanks.

Another question:blush:

Cylinder heads. Reading some of the information is interesting with various thoughts and recommendations.

Should I consider doing my own heads up, say larger valves, HD springs, etc. with a little porting OR are the Chinese castings/performance heads already assembled the go?

Ken


Bizarre - July 19th, 2014 at 07:35 PM

I would go with the CNC Los Banditos from C b Performance


landfall - July 19th, 2014 at 08:23 PM

Quote:
Originally posted by Bizarre
I would go with the CNC Los Banditos from C b Performance


OK, that's where the carby kit came from.

So far I have listed:-

Cylinder heads (CBP)
Gasket Set
Flywheel seal
Flywheel Nut and washer
Rocker Gear 1:4
Mahle Barrels and Pistons 85.5
Push Rod seals
S/S Pushrods.

Ken