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912E Type IV Rebuild

Posted: Wed Sep 06, 2017 7:35 am
by Bsherrard
Greetings to all -
after several months of lurking on the forum, reading posts and researching parts, I am ready to begin the rebuild of my Porsche 912E Type IV motor. I have a post over on the 912bbs but from what I can tell, this forum is "the place" for type IV projects so wanted to post my project to take advantage of all you experts out there. The engine suffered stuck rings which broke when it was started and caused damage to the heads, pistons and some slight scoring of the cylinders. The plan is to rebuild to a 2270 with all new parts except I am going to bore out the original German Mahle cylinders. I have been working with Len Hoffman on the heads which will be the RS+ with a slight upgrade of the valves to a 44 x 38 to match the LE190 heads that Jake Raby used to use on his 2270 builds back in the days when he offered the kits. The goal is for a higher performance Street car with lots of torque, moderate RPM's and compression around 9:1. Don't want to over do it so I have temperature problems. Looking for something similar to the Raby 2270 builds of old. I am sourcing most parts at the Type4 Store. Here is the current planned build specs:

RS+ Heads w/ 44 x 38 valve upgrade
Custom JE 96mm pistons / rings / pins / clips
78mm Forged counterweighted Stroker Crankshaft w/ Type 1 rod journals
H-Beam 5.325 Rods w/ type 1 rod journals
30mm Oil pump modified for type 4 / full flow
Parkerized lifters
HD Rocker Shafts
1.7 914 Rocker arms w/ 911 Adjusters
Chromoly pushrods
9500 Camshaft 1.065 B/C 104 L/C

Certainly open to comments / recommendations / suggestions from all on this build. This will be the first Type 4 I have done.
Brook

Re: 912E Type IV Rebuild

Posted: Wed Sep 06, 2017 11:03 am
by NextGen
HI Brook,
Welcome aboard, You have been dealing with the most knowledgeable guys. I created the Cali Style Conversion using the stock T-1 Bug fanhousings, but when it comes to working with the internals you mentioned I am not in that league, I have 914 2.0 in my bug since 90 when I wrote my manual. From the day I slammed the hood I never looked back - T-4 is the way to go especially in a light car like yours.
This site does have the most experienced guys , but some which are from Europe switch back and forth from the Samba Performance News Group.
https://www.thesamba.com/vw/forum/viewf ... 0b52ba9497

Re: 912E Type IV Rebuild

Posted: Wed Sep 06, 2017 6:56 pm
by cgates30
Brook,
I'm in the process of installing my newly rebuilt engine in a 912E. I installed 96mm and kept the 71mm stroke crank. I haven't started it yet, so I'm still crossing the fingers, but I agree this site is a great resource. I also got good advice from some of the 912bbs folks. I'd like to follow your thread since I a second engine and could regrind the crank and (potentially) have the cylinders bore out like you're doing.
Good luck!
Craig

Re: 912E Type IV Rebuild

Posted: Thu Sep 07, 2017 8:11 am
by Bsherrard
Joe - thanks for the tip to look at the Samba forum.
Craig - I've seen your posts on the 912bbs. here is a link to my build thread over there.
http://www.912bbs.org/vb/showthread.php ... d-for-2037
Brook

Re: 912E Type IV Rebuild

Posted: Thu Sep 07, 2017 5:17 pm
by NextGen
Brook,
you are on the right track, best advise don't rush do it right.

Re: 912E Type IV Rebuild

Posted: Sun Sep 10, 2017 1:18 pm
by Bsherrard
What are the thoughts on distributer for a 2270? I know all the info on Jakes builds say to use the Mallory Unilite w/ vacuum advance which is no longer available. what are some other options / recommendations? I plan to convert to electronic to get rid of the points.
Brook

Re: 912E Type IV Rebuild

Posted: Mon Sep 11, 2017 11:49 pm
by Piledriver
Electronic/programmable, preferably running a crank trigger or high count toothed wheel in the distributor, with COPs or a good waste spark coil.
A distributor with HV is the weak link in any ignition system that has one.
(that's mostly why you won't find one on any reasonably new car)

The CB Black box setup has gotten some decent reviews, but it still uses the distributor for HV steering.
(including some glowing "user" reviews long before it shipped... :evil: )

Megajolt is a Ford EDIS based controller, rids you entirely of the distributor and is a nice bit of hardware.
https://www.autosportlabs.com/product/megajolte/

You can also build an excellent ignition setup using a Microsquirt V3, a VW 4 tower coil and only be short a set of injectors and a high pressure fuel loop from a full EMS for not much more $...

I'd usually suggest a full EMS setup, as that goes the farthest towards making your ride a "real car" that you get in and drive, rather than a continuous maintenance fight, but that's a bit too much of a learning curve for a lot of folks, or expense if they can't DIY.

The Black Box or MJ is close enough to plug-and-play to be a good option, and flexible enough to be able to work properly with a hot cam and webers.(can be DIY programmed)

A solid programmable ignition gets you ~most of the reliability and driveability/performance boost a full EMS can provide.

Re: 912E Type IV Rebuild

Posted: Tue Sep 12, 2017 2:11 pm
by NextGen
Hey piledriver whats the matter you don't like the sound of backfires from dirty jets on Deceleration ??? Just cleaned mine and I have Jet Doctors.

Serious old electronics and carbs are a labor of love.

Re: 912E Type IV Rebuild

Posted: Thu Sep 14, 2017 5:11 pm
by Bsherrard
Two interesting but differing points of view to consider. Thanks guys.

Re: 912E Type IV Rebuild

Posted: Wed Sep 27, 2017 3:15 pm
by Bsherrard
Piledriver -
I have been looking into the Megajolt and it looks promising. any ideas where I can source a toothed wheel for distributor?

Re: 912E Type IV Rebuild

Posted: Wed Sep 27, 2017 6:46 pm
by Piledriver
EDIS (and thus MegaJolt) requires a 36-1 crank wheel and VR sensor.

Mario aka thedubshop.net makes a custom t4 crank trigger wheel/bracket setup that will probably just work given the right VR sensor.
I'm sure he can set you up.
http://www.thedubshop.net

You might want to peruse his other offerings while there, he's very good.
Looking at his new website you should probably PM him.

Re: 912E Type IV Rebuild

Posted: Mon Oct 30, 2017 3:33 am
by Bsherrard
Just to update - after doing some research and them coming across the group buy over on 914World.com decided to go with the Bluetooth programmable 123Ignition distributer. Was able to save 15% due to the group buy. (still going on I think if anyone is interested). Its a solution somewhere between the "old school" approach Joe is in favor of and the full on electronics/coils of Pile. Only time will tell if I have "chosen wisely".
Hope to get my cylinders back from the machine shop this week so I can start working on putting it all back together.
Brook

Re: 912E Type IV Rebuild

Posted: Mon Oct 30, 2017 5:42 am
by H2OSB
Jake uses 123 Ignition these days. Kinda cool...they offer a bluetooth app that lets you adjust the ignition from your smart phone. Little spendy, however.

H2OSB

Re: 912E Type IV Rebuild

Posted: Wed Nov 01, 2017 10:55 am
by NextGen
I know Jake for many years now and it seems he is always going to the cutting edge of designs. From Mallory to 123 and everything in between.
Not that any of those were bad, they were the best at the time, this is just sounds better. You can sit in the bug and do Adjustments from the phone while driving, Or while someone else is driving..


Funny that said, there is something about simple.... at times I miss a capacitor, points and a single barrel carb, ha.

Re: 912E Type IV Rebuild

Posted: Thu Nov 02, 2017 5:25 am
by 999argonaut
Are you keeping the stock FI and computer in combination with the programmable dizzy? If so would be very interested to learn about your experiences and what improvement this would bring. 123 distributor's own website seems to guide people towards the non programmable version if you are using d/j-jet setups.