Ish_944

So I've got nothing better to do, might as well document my build here. Here it goes.

I won an ebay auction for a "rebuilt" engine. It was advertised as a 2.7l, at first the guy told me on the phone that it was a turbo build. Later he admitted mixing things up and it wasn't supposed to be a turbo. That was a plus for me -- no need to change pistons. I also bought the fuel rail, injectors and intake manifold to fit the 2.7l.

First look wasn't that bad.




Up close was worse, but the damage might have been caused during shipping.


A look at the intake ports shows how "professionally" the engine was painted.


It also clearly ran more then the 20m I was told on the phone.
But the previous owner (maybe his name was Tim, never got a last name) said he was a Porsche club member in the UK, thus gotta believe him. Not.

Well, the real surprise came when checking the bore diameter.


So how's it a 2.7l? How did he not know it if he at least replaced the head gasket? We agreed to a partial refund (all the other bits were for an early 2.5l as well, which I didn't need). He would never pick the phone up ever again and haven't seen my money, either. So much for English gentlemen...

V2Rocket

I was going to tell you it's a 2.5
You can see it has 2 bolts in the head coolant port where a 2.7 has just 1.

Ish_944

I wanted to increase stroke to gain some torque which makes driving more exciting. Especially under 3000 rpm I thought I could use some for normal driving.

So I wanted to have my crank offset ground. Nobody was willing to do it in my country.
Hence I bought an S2 crank from England. This time a got really lucky! The crank required no work at all and was good to go with standard size bearings.

However, the rods do not clear the block.


We had to ask Lindsey Racing to order custom made rods from Pauter. We went for the extra light version since I have no plans for forced induction. They clear nicely, as expected.

Ish_944

Forgot to mention that according to Mike Lindsey it is not possible to machine the girdle for the stock rods to clear. One would break into the oil galleys.

924srr27l

Neat, did you not fancy some knife edging on the crank.....?


Lots of inertia once it's spinning of course, but you've got a long stroke to spin up and what bore 100mm?


R

Ish_944

Augtronic with bluetooth connection, lambda sensor, turbo injectors, road race camshaft and other bits and pieces from Augment Automotive. Tom is a really nice guy, a pleasure to do business with, can only praise and recommend him!


The package from LR: silicone hoses, Chevy pistons, rings, Pauter rods, injector harness, Cometic MLS head gasket, seals, oil pan baffle, etc.

Ish_944

Bore is 101.6 mm (4"). Standard size for a Chevy 5.7l.

Knife edge costs a lot. Moreover, I was worried about the engine slowing down too fast between shifts making it uncomfortable during regular driving. This is also why I didn't get a lightweight flywheel. I'm also concerned about balance: how does everything work together with the balance shafts then?

Ideally you go to Chris White or Micheal Mount and ask them to figure it all out, I guess.

924srr27l

Ok, so stock 2.5 bore, but honed......?


I guess I'll soon find out in 16 weeks what a lightweight crank, short stroke and light weight flywheel do to shifts, but I was under the impression that shifting up will be faster ?


Taking your foot off the gas will slow up quicker, but I only take my foot off when I want to put my right foot on the middle pedal....


And how does it, will it all blance out...again no idea..but I've got half balance weights also, so the whole thing is half chips half rice...! lol ...


Could be great for the track, and a pig on the street ? we'll see...


When will this be up and running....... ?


R

odonnell

I have a knife edged crank and no balance shafts. Balance shaft drive gear is also machined down to minimize rotational mass. Also no other accessory drives besides the alternator. I haven't really had problems with revs dropping too quickly, you get used to it like with any car.

924srr27l

Stock fly ?

odonnell

Yessir. At least it felt very stock-like when I pulled it a couple months ago, it's been a couple years since I last handled a stock flywheel.

Ish_944

Stock is 100 mm for 2.5l and 104 mm for 2.7/3.0l so it is slightly bigger.
It was actually dry-sleeved as I mentioned on the previous page. I'll continue the story with the pictures but I had to sleep yesterday night.

It is up and running, I've got ~4300 km in it already. I'll give you all the details as time permits.

Ish_944

So the block was dry-sleeved and bored to 101.6 mm (4") to fit he Chevy pistons.

We went with a piston compression height of 1.425" if memory serves. If I did it again, I'd pick a 1.25" height and go with 4 mm longer rods. That would give the perfect 1.75:1 rod ratio and lower rotating mass. Anyway.




Then everything got painted. No powder coating, because it would have been to expensive and too slow. Good old quality RAL paint is nice.
This time done right, properly masking where it should be.

Ish_944

Some parts were rebuilt, because "while you're at it".
Throttle body:



Alternator:



Nicely cleaned fuel rail, repainted injectors.

Ish_944

Engine test fitting and measurements.
Everything was painted except for 3 things:
- water pump
- oil pump
- throttle body.
Just not worth the effort. Maybe one could still do the throttle body though, that is actually well visible.


















Test fitting the external oil cooler. Note that the sandwich plate has a thermostat and I also kept the stock oil to water cooler.