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Posted by: Michael J Oct 19 2006, 08:32 AM

I am looking at another 914 which has a 1.7 that has been built to what the PO told the current owner is a 1972 cc, some sort of mild cam and carbs. The story is that the case had to be machined to get the big bore kit in. I thought that 96mm cyls equalled 1911cc on a 1.7 and didn't need any machine work???. So if this isn't just a story, and I will get to the facts before I part with any $, is the 1.7 case durable enough to withstand higher compression and generally more stress. Even if it makes 100 to 110 HP that is a big increase from stock.

Posted by: blitZ Oct 19 2006, 08:45 AM

According to one of Jake's broadcast, the early 1.7 cases are a bit sturdier than the later cases. If that's a 1972cc, then it's been stroked.

Posted by: Jake Raby Oct 19 2006, 08:47 AM

A stock 2.0 is 1971cc. It sounds like they dropped 2.0 internals into a 1.7 case-

The 1.7 case is our choice for big performance engines!! I built my 3 Liter engine and the Mighty bSpyder engine both from 1.7 cases (235 and 257 HP respectively)

The 1.7 case is no different from a 2 liter, but in our development it has become very clear that the 1.7 case has better metallurgy than the 2 liter, this metallurgy promotes case strength at high mileage or heavy power output.

I am currently building a 350HP Turbo engine and starting on a 500+ HP Turbo engine, both based on the 1.7 case-

Posted by: Michael J Oct 19 2006, 09:04 AM

Thanks alot - Jake in particular. This helps as i try to find out just what this engine is.

Posted by: toon1 Oct 19 2006, 09:21 AM

Is there a certain casting # to look for or are the 1.7 cases close to all the same?

slight sorry, Jake you have mentioned that a real efficiant combo is a 78/90, what about a 71/90 with 1.7 heads. will this work

Posted by: Jake Raby Oct 19 2006, 09:21 AM

I'll be doing a show on the 1.7-2.0 conversion in November...

Posted by: TROJANMAN Oct 19 2006, 10:00 AM

QUOTE(toon1 @ Oct 19 2006, 07:21 AM)

Posted by: toon1 Oct 19 2006, 10:44 AM

QUOTE(TROJANMAN @ Oct 19 2006, 09:00 AM)

QUOTE(toon1 @ Oct 19 2006, 07:21 AM)

Is there a certain casting # to look for or are the 1.7 cases close to all the same?

The early 1.7 cases (someone said the "sturdier" ones) should have all started with a "W" (including the VW engines)
In '72, they went to "EA", and '73 to "EB".

Posted by: Bleyseng Oct 19 2006, 11:45 AM

the only difference I can think of is the delete of the second oil pressure relief on GC cases.

There are differences internally on cases between W, EA, GA & GC

Posted by: So.Cal.914 Oct 19 2006, 11:57 AM

The bus cases I've seen has the port for the mechanical fuel pump.

I've been running a 1.7--2.0 conv for 20 + years and I am not nice to it by

any means. I've rebuilt it a few times and the last time when I had the case work

done the machinest said the line-bore he did wasn't nessesary, that it was true.

I had the 1.7 heads fly-cut and ported them, I have been happy with the results.

All though I would trade them for some of Jakes... Any suc...ah.. takers.

Posted by: Bleyseng Oct 19 2006, 12:40 PM

QUOTE(So.Cal.914 @ Oct 19 2006, 10:57 AM)

The bus cases I've seen has the port for the mechanical fuel pump.

I've been running a 1.7--2.0 conv for 20 + years and I am not nice to it by

any means. I've rebuilt it a few times and the last time when I had the case work

done the machinest said the line-bore he did wasn't nessesary, that it was true.

I had the 1.7 heads fly-cut and ported them, I have been happy with the results.

All though I would trade them for some of Jakes... Any suc...ah.. takers.

Posted by: PORobinSCHE Oct 19 2006, 06:21 PM

WOWie,,, i love this site. i learn so much by just reading. now i have an even better gameplan for what upgrades on my 1.7L motor!

Posted by: JPB Oct 19 2006, 06:29 PM

QUOTE(PORobinSCHE @ Oct 19 2006, 08:21 PM)

WOWie,,, i love this site. i learn so much by just reading. now i have an even better gameplan for what upgrades on my 1.7L motor!

Posted by: Jake Raby Oct 19 2006, 06:39 PM

People never listen when we say that all Type 4 engines were created equally.. They think the 1.7 is a totally different, smaller engine that can't be upgraded... They think the 2.0 is also a bigger and stronger engine in every way- not true.

The 2.0 internals were derived from the 1.7... Internally and externally the dimensions of the cases are the same...

With that being said the 2.0s are my least favorite for cores for my engines, we don't use the "2.0 heads" anyway and the rest of the engine is usually worn more than the 1.7 counterparts that are years older..

I build all my full race engines on 1.7 cases

I have a lot of new writings being released over the winter on this topic.

Posted by: toon1 Oct 19 2006, 07:08 PM

Hey Jake, can you use a 2l crank with the 90mm pist and cyl. setup.

I'm sure it has been asked before but I don't know the answer

Posted by: Jake Raby Oct 19 2006, 07:37 PM

you could, but the pin height of the pistons would mandate .200+ cylinder shim...

For a Turbo it would be beneficial, othewise its a waste of time

Posted by: toon1 Oct 19 2006, 07:42 PM

Thank's Jake