When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Alright, here is my plight. As some of you know my 81 blew its head gaskets after nearly 37 years of service on the way back from Monterey car week in August.
It made it the 300+ miles back without a hitch in stop an go traffic and never overheated or came close to doing so.
As soon as I let the engine sit for 10+ minutes or so cylinder 3 filled with water.
I found out which cylinder failed after I removed the plugs, activated the starter and had oily water shoot out of that cylinder. It never hydrolocked itself.
There was no sign of significant amounts water ever getting into the crank case as the oil looked normal with no metal specs, just some sludge in the PCV system similar to a car that had sat for a while, nothing major.
So for now it is sitting on the side of my house under a canopy waiting for its engine to be pulled for a full prognosis.
Here sits that poor b*stard:
Now comes my plans for what I am going to do to it with the engine out.
1) I plan on installing 944 turbo valve train in the heads along with 78-79 camshafts when I have them worked over. This includes springs, larger intake valves (same as 928 Euro S).
But most importantly sodium filled exhaust valves, as I plan on adding boost some day ( and maybe convert it to the Miller cycle as I am that crazy) and want the car to be as reliable as possible as it is my daily.
2) I'm going to have them ported to Euro spec/ port matched to the S2 runners on the intake or to the stock runners depending on which has the highest velocity through the ports ( It's getting a complete S2 intake, throttle body and all).
All intake porting will be left rough/ non polished.
I also am going to have the valves unshrouded, and port match the exhaust port to the 85/86 S3 exhaust manifolds along with having the exhaust ports mirror polished to prevent carbon buildup.
The reason I am not buying Euro heads and having mine machined is I want to keep the cold start system in place.
The ports in the back of the heads in the Euro heads go to the exhaust ports for the smog pump and I don't want afterburners in the form of the cold start valve.
The head work will be done regardless of what I do to the bottom end as that is an unknown at this point without looking at the rotating assembly. More on this later.
3) I'm going to install a windage tray and a new ATI damper ( looking at you Greg Brown) as I do rev this engine over 6K often and I would like to reduce oil ingestion ( it leaked more than it used which wasn't much to begin with)
and reduce the aeration of the oil as I would like to track the car at some point. Plus I like having in spec bearings.
4) When I do look at the bottom end I will decide if I buy a 85-86 5.0 bottom end and build a pseudo Euro hybrid if it will cost less to buy another block instead of reusing the one in my car already.
I'm going to reseal the engine and replace all gaskets and seals regardless of which bottom end I choose. I'm also going to measure bearing clearances as per Porsche and see if they need replacing.
These mods are being done intentionally to keep the car smog legal and easy to run using the stock ignition and L jet injection.
This is where the front end rebuild of the thread comes into play.
5) I'm going to have the frame of the car inspected and straightened if needed as at some point in its history the car was in a unreported front end collision and had its frame repaired.
The reason why this is an issue now is that the fender holes to mount the passenger's side fender all don't line up.
2 don't line up well past the suspension mounts. So it isn't structural as the car can get an alignment mostly within spec (only caster is out of spec and not much).
It's just that the body panels don't line up. It bugs the hell out of me any time I open the hood.
6) I'm going to have all of the holes plug welded that were used to straighten the frame previously as they are rust problems waiting to happen.
7) I'm going to paint the engine bay with Glasurit black metallic paint of the non California compliant variety as I want it to last longer than 5 years . The original paint lasted 37 years after all.
8) I'm going to replace all wiring under the hood of the car (main front loom, engine harness, and fuel injection harness).
All of them are crispy, have shorts/degraded insulation and broken connectors. I don't want to touch them for the next 30 years and I want to get rid of as many gremlins as possible.
9) I'm going to replace the upper and lower A arms with rebuilt units so the car can actually have an alignment be within spec.
The bushings failed due to age and oils leaking onto them. Nothing new here. Plus I want the car to really feel like a new car after this.
Here are where all the sub threads of this will be linked to when they get created:
Exhaust - you'll pass smog all the same with 85/86 manifolds or even a complete 85/86 exhaust. The early CAT arrangement is a bottleneck
Assuming you want to re-ring this engine, the 85/86 lower end will probably be cheaper unless the cost of the 4.5 rings have dropped significantly
L-Jet may be your biggest headache if this engine produces any significant power over stock. There simply is no "easy" way to tell this system to supply more fuel upstairs without flooding at idle. You might get away with a RRFPR. There are piggy back modules which will work to add fuel when needed or to dial it back at idle / cruise if you go with larger injectors. Getting it to run good but a bit on the rich side really isn't that difficult, but those who make such claims probably didn't also have to pass Cali smog tests....
That's why I scrapped L-Jet and converted my 81 to LH/EZF from a EuroS complete with the twin dizzy. Nobody would know my car wasn't stock unless they know the twin dizzy wasn't available in 81 (well and the supercharger...)
I have a set of B1 DEVEK camshafts. I called the two cam companies in SoCal, one of them has the DEVEK grinds on file and can duplicate them. Mine used the EuroS cams as blanks, but we discussed the possibilities with stock US cams. Per their records they can come close to if not exceeding EuroS spec using US cam blanks. Lash caps will be needed.
I'm 99% sure it was Web Cam I was talking to. I was going to send them some US cams to re-grind but never got around to it.
How do you intend on implementing the Miller Cycle?
From the little I know about it, it sounds like using an intake cam with lots of duration holding the intake valve open on the compression stroke, thus reducing the dynamic compression ratio. A blower is then used to compensate for the loss of the mechanical compression and efficiency at lower engine speeds.
If that is correct, what are your specific plans and what do you hope to achieve?
I plan on keeping the stock cat for now and maybe going up to a used dual cat later.
Trouble is I need to run a dual exhaust after that or weld some downturns onto the cat and **** of the neighbors.
For me, finding a good used 85-early 86 exhaust is a bit challenging. I am also missing a rear hanger mount so I cannot run a rear pumpkin.
Ring prices are still $1000 for a set of 81 rings so it will be cheaper to rebuild a good used 85-86. But the rings in the 4.5 rarely wear out due to the low amounts of stress.
After I get it running on the L jet I plan on using a second L jet computer I bought and sticking a megasquirt 3 in it, first done on the Alfa forums here: http://alfagtv6.com/MegaSquirt/Megasquirt.htm to get me some tuning abilities.
I don't intend on modifying the ignition yet so it will just be controlling fuel. Making use of the stock wiring easy and essentially making a plug and play system.
I'm essentially making it a plug and play swap for diagnostic purposes. I just need to make a L jet harness with the injector pairs moved around to get me semi sequential injection. Mine's a bit crispy.
A set of hotter cams than the pair of 78-79 cams I have would be great, but I don't want to spend $1200 on a set of custom cams and would rather invest that on some Greg Brown goodies like a crank scraper and ATI damper.
I'm just a freshly out of school 21 year old pastry chef after all. I don't have massive funds.
I did wind the 4.5 to 7K frequently so I want to improve oiling and reliability in higher rpms, which is the main area these engines struggle with.
Miller cycle is just a set of custom cams that stay open during the first 20% of the compression stroke and a low rpm source of boost. Pretty easy to implement (especially on 32V cars), just expensive. It's my end game.
Time for an update, the engine is out and a 5.0 bottom end is going in.
I recently dropped of the heads and 100mm pistons off at Engine Supply to have the heads ported, new valves added and all around reconditioned.
That means the valves are getting unshrouded, the bowls are being blended, and everything is getting port matched to improve velocity through the intake tract.
The porter calls this a stage 3 port job and is the last step before a full blown race port job. Which for $400 is more than fair in my opinion for the experience this guy has porting.
I didn't opt for a race port job as I'm after low and mid range power, as this is a street engine and will rarely go above 5,000 RPM. Top end power isn't my main concern.
I am having 944 turbo 40mm exhaust valves stuck in the heads to reduce valve guide wear and prepare the engine for boost in the far future.
Plus I got lucky and Einmalig didn't update their pricing on 45mm 928 Euro intake valves so I got them for $17.50 each for genuine Porsche valves vs. the $170+ that everyone wants for them now.
Now I wait to hear back from Engine Supply about how much $$$ I'm going to need to dump into these heads in guides, seals, and machine work on their end.
It's the opportunistic shark parasites that ruin it for everyone.
I don't think Einmalig has updated some of their prices in 25 years. Either that or they honor the original price of the stock they have and only charge more for new items they acquire.
Either way, you sometimes get lucky with them on high dollar unusual parts like the valves.
The engine is coming together nicely. I just need to get a gasket set at this point to bolt the rest of the parts onto it.
Balancing the rotating assembly with a dremel was a slow time consuming pain that sent metal shavings everywhere. I'll wait and see how well this engine runs in the coming months.
I decided to save some money (~$500 vs >$2K) and line the engine bay with silver heat reflective foil instead of painting it. It will definitely be more interesting to look at as the car is never going to be a garage queen or show car.
The product I will be using is DEI Reflect-a-cool sheets. They're good for 400F direct heat and 2000F radiant. Shouldn't be a problem in our cars. Especially after I get the manifolds ceramic coated by Swaintech.
I have all new wiring ready to go as well. Things are going to get interesting soon.
09-27-2017, 02:13 AM
1981 928 engine/front end rebuild planning thread
. The original paint lasted 37 years after all.
