BritishV8 Forum

General Category => Engine, Transmission, & Rear Axle assy. => Topic started by: roverman on May 20, 2016, 11:23:44 AM

Title: Type IV Porsche Engine
Post by: roverman on May 20, 2016, 11:23:44 AM
Perhaps someone here, has experience with these ?  Yes I know, not too likely to find in a BSC.-but ?  Plan is to use Scat individual heads, 76-78mm stroker crank, I make the 101.3mm alloy barrels,(nikisil).E85 fuel should help cooling, as with 911 type fan.  Problem is, I have these Pankl  Titanium rods, I MUST run,(too cute/light not to). Since the bolts install , heads on cap, they will likely bang the cam. Not likely viable to reduce the base circle enough to clear. Type IV has 11" push rods, ie. massive aluminum thingies !  I'm considering converting the heads to "overhead cam on follower".  This would solve two big problems,(cam interference and clunky valve train), but with extra work involved.  Anybody ?  Thanks, roverman.
Title: Re: Type IV Porsche Engine
Post by: MGBV8 on May 20, 2016, 12:08:57 PM
Art, did you just say P-p-p-orsche?!  Such sacrilege.  :)
Title: Re: Type IV Porsche Engine
Post by: DiDueColpi on May 20, 2016, 04:47:02 PM
Art,

Just say no to Porsche. The 911 fan conversion is a no go.
It uses double the horsepower to run vs the VW stuff. And it's a low pressure high volume design.
The VW engines have very restricive cooling passages that need the high pressure stock design fan.
Make sure that you retain the thermostat assy as well if you want your engine to stay alive.
You are right your "must have " rods will probably hit the cam.
Depending upon your use, those big clunky aluminum pushrods might be the best choice. For a street motor they follow the expansion rate of the motor better. For a race engine something stronger should be used.
There are some OHC conversions around. Most of the older ones used modified 911 parts.
I haven't followed any of the newer efforts but what about Subaru heads? Water cool the heads only and away you go.
Title: Re: Type IV Porsche Engine
Post by: roverman on May 20, 2016, 05:38:06 PM
Thanks Fred, word on the street is to run Manton, tapered-wall chrome moly PR's. Hot lash the motor and check for "real close" at cold ? Yes, if I had any sense, I'd just bolt-in a Sub motor.  Less pain, more gain ?  Were I to use non Scat heads, this anchor has same bore spacing as 460 Ford, hmmmm.  I have an as-cast head, arriving from Scat. Let the flow bench, games begin.   Onward, roverman.