Mike Simard

edit: SOLD

For sale:
My lifelong culmination of the ultimate performance engine. It has been everything I hoped and surprised me at how good it is. I've had it in my racer, it's too powerful for most classes and broke 2 transaxles in a row.

This engine is too good for a race car and deserves a nice 928 chassis that can be enjoyed on roads, in traffic or track days. The 427 cu in displacement, ITBs and 32 valves make for a rare treat of nice street manners but the ability to make huge power and not be stressed.
It will be happy in traffic on a hot day and on 93 octane.
Because of the lightweight reciprocating mass and flywheel, it can free rev at 18,000 rpm/sec.
I have faith in it going cross country right now. It has never run hot, even on hot August days racing with a stock radiator.

Bore x stroke: 109mm x 94mm

Block:
S4, custom Nikasiled steel cylinders. Individually removable for service.
Case halves "shuffle pinned" with dowel sleeves. Align honed.
My special main studs installed with girdle/pan spacer.

Heads: CNC ported to my ITBs. Titanium valves, (surplus IRL)

Cams: 12.7mm lift intake and exhaust. Custom steel billet.

Crankshaft: Moldex 8 CCW

Connecting rods: GM Titanium. My own special small end bushings, modification for piston centerness and my special proprietary method of sizing the bushing. I'm very happy with these.

Pistons: Custom CP, from forging. lightened 368 grams. Close fitting box design which is superior to old fashioned forgings.

Rings: Total Seal, 1.1mm, 1.5mm, 3mm oil ring with superior compression spring and Nikasil compatability.

Induction: 56mm ITBs. Designed specifically for the 928 intake tract. I'm very proud of these and have been surprised at how well they work.

ECU: Motec M48, sequential injection and sequential COPs.



I could also sell the entire car too, it's rather special with some properly done suspension changes and a unique Jerico transaxle that is bulletproof.

I'm selling because I've been working on a completely different personal project and feel like I "completed" the 928 quest and this seems to happen with me when I feel something's complete and a success. I'm not getting out and will still make parts for them. They are still my all time favorite car.

pics coming...

Tony

Hey....Sterling!!

even though you have completed your "928 quest" dont leave this place!

Mike Simard

Other notes:
There are a lot of details in this engine. Some examples are cam followers that are hydraulic but I've modified the travel and set them up as mechanical. That means they have the benefits of hydraulic but can't collapse or pump up. This mod is not easily done and takes special equipment that few companies have, in this case a Wire EDM with rotary axis.
The oiling system has special mods that will be handy whether it keeps it's dry sump or a normal pan installed.

Mike Simard

more

Mike Simard

Here's from tuning on a Dynojet. I have a really good tuning guy locally at Balanced Performance. We spent a morning tuning and this was the big 'bragging number' run after the work.

The car now has larger injectors since then which I feel was a problem before.
Time with a good tuner on a chassis dyno once installed is important.

(Find a tuning guy that is hard to get appointments with because he does track service for pro teams!)

Mike Simard

More details. Here's the dry sump as fitted now.

The other pic is a new camshaft sensor. By moving the sensor to the left side, it sees less theoretical influence from the timing belt and is a common, robust sensor as used in motorsports.
It wasn't necessary but typical of attention to detail.

Mrmerlin

Thats pretty darn nice Mike GLWS

Jim Morton

Amazing... simply amazing effort !

GLWS

john gill

That is an amazing story Mike , what are the COPs that you have used ?

Livio928

Absolutely stunning! That looks like a piece of art. My concern would be to get parts made in the future, if this was all propreitary and only available by one or two sources (if you know who they are)

928mac

Very nice Mike. Thank you for showing the detail in the parts and specs. It looks like you got the centering of the GM rod right.
Am I reading it right that you have spun it up to 18,000 RPM or is that calculated?

I like all the custom part brands that you picked.
What was your other consideration for a crank then the Moldex
You definitely will not want any side loading from the rods with those short skirt light CP pistons and it looks like you took extra detail there right down to the wrist pin bushing. Beautiful truly Beautiful pistons and rings.
1 question here,... How are those rings for seating on the Nikasil liners? have you used them to these liner/coating before and are they a hard break-in?
The ITBz ... one word .... Sweet!

All in all Mr Simard My hat is off to you but I do feel that an engine of this capability would be a waste in a street car. It should be competing

Mike Simard

The COPs are a BMW item that I know to be robust from customers that race them in GrandAm. I'll get you the part numbers when I get time. Not all coils are reliable and they do fail but these are known to be good.

I feel the healthy ignition of this engine has been it's secret for not having detonation problems.

I fit them with custom machined nylon sleeves with an O-ring. When you insert them in the heads, the O-ring provides sealing and anchoring. They don't fall out but can be removed quickly if needed. It's another of the details that I've very happy with.

Mike Simard

Motec provides data logging so you can see things like rates of change. A throttle blip that sees 1-7k in a third of a second would yield something like that number.
I shouldn't have listed that, it must be confusing.
Quick throttle blip engine revs are something I always wanted because of down shifting and general 'athletic' ability in an engine.
There's one turn at Road Atlanta that is at the end of a long straight and downhill. Being able to blip the throttle to match revs quickly when downshifting would be a treat. Other engines I've had over the years are typically slugs and by the time you blip the throttle and the engine responds, it's too late.
That's mostly rotating mass and the ITBs but also the engine management. Motec is a top notch ecu that's sequential and has good resolution to be able to react to changes within milliseconds and not wait around to see full revolutions.

About piston rings, your idea of "seating" does not really to modern materials and high quality fits and finishes. In motorports, nikasil type cylinders are common and so are coated rings. There's no "seating" going on.

85euro928

I've always admired this engine and how simple it all appears; the sign of a well engineered machine. GLWS and your future projects.

Mike Simard

Random detail:
The piston skirts do not protrude at all from the bottom of the cylinders.

This is normally not possible in a traditional block even with a stock stroke.
By having removable cylinders, I was able to make them with 'coat tail' extensions for the pistons.

The benefits are full support of the skirt at downstroke which yields better ring sealing by preventing excessive piston rock.
In domestic V8s, pistons poking out the bottom of cylinders is normal and 'stroker' engines are 'dirty' with oil in the combustion chamber and the detonation that causes.

Someone asked about rings and how I know they work.
Since I enjoy building and working on engines more than driving them, I've "rebuilt" this one several times. It's never had much use but I wasn't happy with the first set of pistons and their rings. I've had the cylinders re-coated and honed for the new pistons because I wanted everything right.

I understand what kind of rings are required for nikasil.
I've also noticed that the sealing of the cylinders as fit to the block, both head and lower block, is reliable with no indication ever seen of any kind of leakage at all, even after re-using the Cometic gaskets.

I have seen how the parts wear after teardowns and have a reasonable feeling of confidence in this engine based on experience. If I didn't, I wouldn't offer it for sale.