SR20 Strip Down - Part 2

Yesterday I completed the tear down on the SR so it could be sent off to Heinz for the bottom end rebuild once the replacement parts arrive. The task though was to remove the crank, rods and pistons so all I was left with was a block.

- SR20 Crank girdle and oil baffles
- SR20 GTi-R Oil Pump removed



Once the oil pump was gone, the girdle could be removed and then the main caps for a good view of the journals and bearings. These are Eagle Forged Conrods with ARP rod bolts. The journals seem to be on OK condition and should just require a polish.

- Piston 3 Conrod caps
- Piston 2 Conrod caps
- Piston 1 Conrod caps
- Main bearings - show some heavy usage
- Close up of the bore
- Close up of the crank journals
- Rod and pistons now removed
- Eagle Rod with Z32 piston

After this was all done, it was time to put the shopping list together. I made the decision to no longer use the GTi-R oil pump as after a bit of research it was hit and miss on the whether or not the oil leakages can be stopped. It will be replaced with a standard S13 pump and we'll get the gears cryo treated for some extra insurance. With the reversion back to the standard pump, the GFB light weight pulley will no longer fit properly. This means with another GFB pulley, a standard SR20 dampened pulley or another aftermarket one. I'd heard nothing by good things about the Ross Harmonic Balancers, and although a 4-cylinder doesn't really need it, it's just good to use them anyway. So that will be on the shopping list.

Of course the Tomei metal head gasket can't be reused without a few hours work so a new one will be ordered. Now the big question comes around pistons...what to get. The original intention with the engine was response over all out power, and after good results from other engines C-Red had built with higher compression pistons, the decision to order a set of CP Forged Pistons with a 9.0:1 compression ratio has been made.

If you remember back to the track day, I was a little surprised to see oil up on the intake side of the engine and my thoughts are that the sandwich plate for the GReddy Oil Cooler kit is a potential fail point in the system. It uses only a single screw in the centre to latch onto the original mounting for an oil filter. I'd been eyeing off an item from Tomei call the N2 Oil Block which basically replaces the standard factory oil block with one that takes -10 AN lines instead of a filter...tick! The last obvious item is a replace releave pivot in the form of a Nismo Reinforced Release Pivot.

So now it's a matter of waiting for the parts to come in and then send off for bottom end rebuild. I thinking that will put us fair and square in the Xmas shutdown period so I am expecting some delays. Not to mention I know I have too much work on too.

Cheers
Brendan

SR20 Strip Down - Part 1

After the engine was taken out, I had a chance to talk over the plan with Marc, Josh and Boney from C-Red. We knew we'd be removing the head and doing all the stuff around that - alleviating any problems with the valve seats being too far gone. But that left the question on whether or not to freshen up the bottom end while it was out doing rings and bearings. That lead on to the question about the pistons. During tuning, Sean at Allstar had mentioned the engine getting a little 'noisy' up high...possibly a function of the pistons being standard Z32 pistons. The consensus from all was that it would be prudent while the opportunity was there to go with a set of forged pistons. These would then match with the Eagle conrods already in the engine with the Nissan bearings being replaced with ACL Race bearings to top it all off. So the strip down begun...



Firstly the cam cover was removed and all the camshafts were removed to allow access to the head studs.

- Specifications on the GReddy Pro Exhaust cam - 264deg 11.5mm lift
- Adjustable Cam Gears - unknown manufacturer (more than likely from Japan)
- GReddy Cams out with Tomei Rocker stoppers in the box
- GReddy branding on front camshafts
- IN and EX label on GReddy cams
- Close-up of specifications and serial number on GReddy Pro Cams
- SR20 Rockers and Cam caps all lined up - all seem to be in good condition
- SR20 Adjustable cam gears front
- SR20 Adjustable cam gears back
- Spark plugs looking pretty good

Now the reason for choosing the head in the first place was the porting and knife-edging that had already taken place on the head. In hindsight (which is a wonderful thing), I should have looked more closely at the head for the valve seat condition and depth.

- SR20 Head porting on cylinder intake 1
- And then well matched across all cylinder intakes



Now that the head was off, it was time to see how the pistons and bores had fared. These pistons came originally from the engine that came off of the shelf for SILLBEER - it didn't have an engine in the hole when I started. We eventually figured out they were from a Z32 VG30DETT engine and were fitted to this engine when it was rebuilt in Japan. We decided to stick with them originally because I was running short of cash, again in hindsight I should have just waited until I had some more fold but...meh.

Note the numbers on the top of the piston for reference are '2 EMO' followed by '45V' and '04'.

- Cylinder number 2
- Cylinder number 3

Just a slight amount of carbon built up.



Next item was to remove the gearbox and confirm the breakage that occurred at the track. Looking at the inside of the bell housing, the clutch fork was loose, and no longer attached to the release pivot. The snapped release pivot was indeed the failure - seen above as the nut looking thing to the lower left of the input shaft.

- Release Pivot Ball snapped off inside clutch fork
- OS Giken STR Twin plate clutch
- Broken SR20 Release Pivot

And that was pretty much the day. Here's a few shots of where I got to after about 3hrs or so.

- SR20 stripped intake side
- SR20 stripped exhaust side
- SR20 front with oil pump still fitted
- SR20 sump removed showing crank girdle

Next week I'll finish off the rest of the tear down removing crank, rods and pistions, oil pump and anything else left over.

Cheers
Brendan