1700cc turbo wedge build

[Music City Lotus]

I started to build up a 1700cc turbo wedge with 79mm liners and pistons, and parts that I accumulated over the years.
So far I machined the liners to fit into the 821 block. The wall thickness is at 1.6mm at the bottom, which is just enough to not worry about it. I'm working on the correct deck height right now.
I use 4130 ChroMo rods with ARP bolts. The wrist pin diameter of the 1700cc pistons is 21mm, and the rods have bronze bushings. So I made Teflon buttons to keep the wrist pins in place, as the pistons have no retaining c-clips. The rods are China specials, but I know a bunch of people who use them with no problems. They were not 100% round at the big end, so we machined them to fit the shells perfectly. Magnafluxed and ready to go!
Crank was ground 0.25 under with new shells.

[dakazman]

Nice Work!
 So is it safe to say you’re a machinist or have access to a shop? Lucky dog...
Keep posting please.
Dakazman

[jbcollier]

The Chinese have been known to go bang.  Perhaps not often but it has happened.

That looks like very high compression for a turbo.

[Music City Lotus]

I have access to a full machine shop at work.
The compression will be at 8.5:1, it will be kept under 1 bar boost pressure. The head will get de-shrouding around the valve pockets, which will increase chamber volume. Squish is at 0.7mm.

[jbcollier]

Might want to section a junk head first.  Not a lot of meat before you hit a water jacket.

Cool project which I'll watch with interest.  Was thinking of something similar with a crossflow -- little easier to reduce the compression.  I assume you'll be running a full engine management system?

[Music City Lotus]

I go back and forth between a Weber clone throttlebody and oldschool blowthrough DCOE carburetor. Just to keep it period correct. I own 2 turbo bikes, one oldschool suck through, one fuel injected. I'm aware of the disadvantages of the oldschool. But I like the simplicity... And I'm not going for crazy hp.
The head mod can't be too radical, agreed. The piston compression ratio is 9.3:1, and I might take a hair off the piston top to set the squish band. So I "should" be able to get to 8.5 without too many yoga poses 

[gideon]

I am also watching with interest.  Please keep us updated with progress when you can.  Can I take it that you won't be using an intercooler?

[Music City Lotus]

No intercooler planned. At this low boost it does not make too much sense, and goes against my simplicity approach.

[Serge]

Nice idea! Great to see other people working on the wedge head engine!

Don't worry about hitting water jackets when deshrouding the valves. I deshrouded mine to a 82.5mm cylinder, and I didn't hit anything.


I am building a 1796cc N/A engine, high lift cam with big compression. I have just finished all my head work, I have made a video about it, will be on my youtube channel in the next few weeks.

My block will still need machining, but I will have very little left between the cylinders. I am using centrifugally cast ductile Iron liners, so should be strong enough.

Serge
http://youtube.com/sleursmotorsport

[Music City Lotus]

Serge, thanks for the info! And quite the restoration you are doing!