You filled the water jackets surrounding the cylinder walls, on an engine you were rebuilding, with either bedding compound or epoxy. What was your goal or purpose? Was it to strengthen the cylinder walls? You have restricted the cooling capacity of that engine. Is that engine running if so, does it run hot?

Just looking for ideas for my HP project. Any information would be appreciated.

Steve C
The Great White

 

Steve,

That would be this guy:

www.928sg.com/block.htm

He give an explaination of why he filled
the block there.

 

Steve,

The person who you may be referring to is Sterling G. His website is 928sg.com.
The purpose is to strengthen the lower cylinder wall and reduce flex, since you don't need it for cooling anyway. (Porsche studied this and found out that the heat was mostly in the top 2-3"). Last time I heard, he was still working through vario-cam issues, but I may have missed something.
There is no cooling problem, if you do it correctly.

There are a couple of specialized compounds for this purpose. I know you can get one of them from Jeg's. I don't recall the names.

FWIW, I know that Anderson (928 Intl) runs 104mm pistons in his racer (an overbored 5L), and does not run a deck plate or filled lower block - and it seems to work. But that's a race car - not a street car.

If you want really big HP, filling the lower block, and a custom deck plate are definately the strongest way to go. If you want good technical intro on this, Sterling's site is a nice start. If you want some hardcore tech on the subject, you should email Garrity (look in the Tech Advisor section). He has done more a couple of deck plates for 928s (and 944s). I fairly certain he has also "grouted" some in combination with the top plate.

There is a fair amount of semi-custom work involved with the top plate, expect ~$1000 to do it right. But, in the end you get most of the strength of a solid block, with the heat transfer of wet liners.

Let me know if you need more info.

Greg

 

I'm also running 104mm pistons in my street/race 928. There are no problems with strength or cooling but creating a custom piston that will work in the Alusil block was very expensive.

Jim Nowak

 

Jim,

Curious as to what the rationale was for going custom pistons vs. going 968 pistons (also 104mm). Was this due to a valve pocket issue on the 4v pistons?

Greg

 

Steve,
I used to subscribe to quite a number of Hot Rod type magazines and I noticed in Ford and Mustang's at least three articles in two years on the subject of pouring Cement/mortar mix down the jackets of 351CI Fords though I can't remember wether it was the Windsors or the Clevelands. As I recall the common theme there was the same as posted by Greg. Apparently, this is more common than you or I would expect and is 'fairly' common practice.
However, IMO, if you use tap water in place of distilled water there is BOUND to be some leaching of calcium from the mix -sediment-. And due to vibration, torque flex some where along the line cement/mortar/epoxy is going to say goodbye to a bit of it's accretion at which point I would like to have a spare water pump on hand as well as a high pressure flush kit...new belt while your there...blah, blah, blah.
You know... I thought when 'they' went with the cylinder block cradles this practice faded away. I wouldn't do this.
HTH
Keep em' rolling.
John S. & Pattycakes

 

Greg,

My engine uses 1985 1/2 944 2-valve heads.

Jim

 

Thank you Jim V., Greg, Jim Nowak, and John S.

Sorry Sterling I did not remember your name.

Jim Nowak, did you use any filler in your engine block? When do you expect to have dyno numbers? Who made your custom pistons? And if you don’t mind me asking how much were they?

John S. I have been in the automotive industry for twenty-five years even though my field of expertise is drive line (transmissions, transfer cases, differentials) I have rebuilt a lot of engines for my projects and others. When doing so I have done a lot of research and spoken to a lot of people. I can honestly say I have never heard of filling the water jacket of a block in order to strengthen it. Maybe this a common practice in the European automotive industry because they like to build hollow engine blocks. Thanks for the info.

Greg, I didn’t forget the manual shift conversion. I have the extra governor, but my great white is hibernating. If I get an MB in my shop I’ll try it out. I’ll let you know.

Part of my project is to bolt my euro intake to a 32-valve engine even if I have to fabricate an adaptor plate. Do you have a two-valve intake you can loan me just so I can size things up?

Special thanks goes to Jerry 87. 928S4. I will soon have an 87/87S4/M28/42 engine for my project. 316 HP – 317 ft lbs of torque.

Steve C
The Great White
85 928S EURO

 

I would guess that it would be beneficial if you had the Throttle Body specs first (effective diameter). Bolting the Euro Intake up will probably be for not if the Throttle Body is not larger (ie pass more air flow) than the S4 does. My S4 Intake is curently off for some 'clean up work' - I'd be glad to take some measurement for you for comparision if you'd like Steve!

Best Regards-

 

Steve,

No, I didn't use any filler in the engine block and the engine builder, from Devek, doesn't think it's necessary.

Unfortunately, I won't have dyno numbers until at least mid to late march at the earliest. My engine builder has been consumed with projects for the military since 9/11. However, he is expecting over 320 RWHP on a Dyno Jet. I have been told given the modifications that estimate may be very conservative.

I'm using J&E pistons with a special coating to work in the Alusil block. The cost was around $800+ for the pistons and $1,000 for the coating process since it was a small production run of sixteen pistons. Reynolds aluminum used to do the piston coating but the company no longer offers this service. The 928 block is made from Reynolds 390 aluminum so who else would know more about the 928 metallurgy. I wish I could tell you who did the coating but my engine builder considers the source of the coating proprietary information.

Jim Nowak

1979 928
88 S4 block
5.4L 104mm J&E pistons
85 1/2 944 heads
Devek Cams
Redrilled crank
Jet Hot coated headers
Extrued Honed Euro S intake
Electromotive Tec II engine management
Devek radiator
S4 cooling fans
S4 front suspension & brakes
Etc., etc.......
Supercharger next!

 

Steve,

I'm sure you may have considered this, but just in case you haven't... You might want to cc the individual intake runners on the S4 manifold vs. the euroS intake runners. 4V heads have different resonance frequencies than 2V heads, and I would imagine the runners are slightly different in length. (And when you get that 87 intake, pop off the side covers just to check out the casting of the runners and bells. Kinda neat.)

Unfortunately, I skipped a day at the shop, and didn't get a chance to check if the manifolds are a bolt-on swap. Pretty sure you'd at least have to do some port matching, but that's no big deal. I'll check in the shop for an extra 2V manifold, but most of the engine parts are 4V.

I've been working through design of a custom intake - individual throttle bodies. Probably will be a couple of months before I do a prototype though. It won't be completely conventional, so there's a little more to the design side than standard throttle body set-ups. Also, have to decide what heads to set it up for.

There are several manufacturer options for custom pistons to work with our blocks. Mahle (OEM) has moved all of it's custom ops to the USA, so they are a short trip. There are also the 968 pistons, which are 104mm, and not too hard to source used. (read: inexpensive). They are also cut for a 4V head, so other than checking all your clearances, and maybe a little flycutting, they are an option as well. There's also Omega, all in house from cast to finish, but they are in the UK.

John,

It's not exactly concrete per se. Kinda close . The 'Hard Blok' brand is cement based. There is also a Moroso product which I think is a bit different in chemical makeup, but I'd have to check. I do recall reading about another brand that is a metallized epoxy of some sort - like a quasi JB Weld. Just can't remember what it is. Ugh. I do understand your concern, and quite frankly. I'll probably stop at deck plates myself, I think that will be adequate for my purposes. You are right that it is a relatively common practice on the world of drag racing. In fact, some of the ultimate custom 3K HP+ blocks are solid. No water jackets at all.

Greg

 

Look what i found, Summit racing catalog
2002, green cover. page 26
"HARD BLOK WATER JACKET FILL"

Steve C

 

Jay,

That would be great, since my engine did not come with an intake. When I measure my euro throttle body I will post the numbers. We can compare bore diameters.

Steve C

 

Steve,

If you're price shopping, Jeg's (www.jegs.com) also sells the products I mentioned.

Greg

 

My euro runners flow 215 CFM’s. My intake will be ported to the heads. The heads will have large intake and exhaust valves. The rule is intake valves 52% of bore diameter, exhaust valve 75% of intake valve.

I’m waiting to hear from extrudehone on a price to flow test and rework a S4 intake manifold.

Any good machinist can bore out my throttle body. The only issue is making a throttle plate to match the bore diameter. I’m going with billet rods from Pauter Machine.

I may go with nicon/nickel silicon coated cylinder walls from US Chrome.

104-millimeter custom pistons from JE machined to match the bigger valves in the head. I’m thinking about using dome pistons, maybe 11.1:1 compression ratio. I’m also having the crank redrilled.

I have to speak with Jerry Roche from JE first (on choice of pistons, flat top or dome). I have emailed others for more information. As for me, a water jacket filled engine on a street machine is more of a liability then a benefit. I would like to know how many 928’s street machine, daily drivers are out there making cross countries runs on a hot summer day without have an overheating problem.

I'll be very disappointed if this engine can’t push 450hp N/A.

I'll keep everybody posted as this progresses.

Steve C
The Great White