turbo and tranny questions

I manufacture turbo kits for water cooled vw engines, so far I have never turbo an air cooled engine and I'm planning to do that to my soon to be reallity speedster, so for the tech expert I have a few questions:

what's the compression ratio of a standard 1600 cc vw bug engine?

what's the compression ratio of a bigger displacement engine like 1776 or bigger in their "standard" configuration?

what will be a better suited trans gear ratio for a let's say 150 or 200 hp turbo engine for nice freeway cruising?

thanks

what's the compression ratio of a standard 1600 cc vw bug engine?

>>>from 7.3:1 - 7.7:1 according to the year and application.


what's the compression ratio of a bigger displacement engine like 1776 or bigger in their "standard" configuration?
>>>>>we don't have standard CR. Our CR is easily adjusted with shims to alter the cylinders position with the piston crown. You can set the CR pretty much anywhere with these engines easily. Most people shot for 7.8- 9:1 for street engines. Our engines cannot run super high CR or they have detonation issues. I run most of mine from 8.8- 10.5:1

what will be a better suited trans gear ratio for a let's say 150 or 200 hp turbo engine for nice freeway cruising
>>>>>>>Thats 100% according to the rear tire diameter and the intended cruise RPM. These engines can negatively react to super tall gearing because they must keep the cooling fan turning.

These engines are VERY different from watercooled engines. There is a demand for Turbo set ups and its increasing all the time...

Jake Raby
Owner, Raby's Aircooled Technology
www.aircooledtechnology.com

thanks jake for the responses
in my young times I rebuilt a few vw bug engines in my garage and I'm kind of familiar with them (living in mexico thru college helped in that department, since I had a bunch of them) but I have been away from aircooled engines in a while, the turbo kits for watercooled engines seem to be way more involved due to what you mention, not taht easy changing of compression ratio, In my experience based on 10-15 lbs of boost you want to stay at 8.5:1 max so no detonation occurs (or limited for that reason)

for fueling I use megasquirt on my watercooled engines and is very good, laptop pragramable and gives me all the fueling necesary and the reliability with modern technology, electronic injectors etc.


another question (sorry if I abuse)
on of the things that the megasquirt standalone needs a good clean tach signal, will an ignitor or any other drop in electronic ignition will be sufficient for tach signal?

thanks a lot again

i'm sure everyone has different thoughts on the subject but I
love turbo's. I've been gathering goods to make my homebrew turbo
this coming season [in nj the weather and free time sets my pace].
T-3, hide away header, etc..I do have a sidedraft carb [40mm]
available but i really want F.I., we'll see.
i just feel the power that is available from a turbo and proper
fuel managment can't be matched. I want a progressive [read lower rpm]
powerband that once it starts it just keeps going. Thats also why
i prefer turbos, the "pull" once its "on boost", gotta love it.
I think [imho] if you concentrate on engine/fuel managment you'll
do well. "Most" of the cheapy drawthru systems do very little [if any]
real fuel management changes, severely limiting the package.
I don't know if you are aware, i'm sure you are but the stf web
site and turbomania have quite abit of info. good luck with your
project.---bruce

There is an excellent, recently published (last couple of years) book on turbo and supercharger engines that also covers many other engine considerations. Pat Downs builds turbo type 1 engines at CB Performance.

Take a look at Harley Davidson's V-Twin SC's