Engine Rebuild

When we first got the car it was pretty much standard with only a K&N air filter as a modification, here is a picture of the engine bay before we started tinkering with it: -

We bought the car with the intention of getting some big bhp, whilst also taking our time over the project. This was soon taken out of our hands when the standard engine spun a bearing and caused damage to the bottom end. We took the engine out ourselves and started to get things together ready for the rebuild.

We decided to bite the bullet and go the full hog with an engine rebuild, not an easy prospect to be faced with when you have almost no experience with the car.

We spent hours talking to different members of the GTIROC, some who gave us much valuable information and really good insight of the GTiR’s SR20DET engine.

At first all we wanted was a reasonably powerful and strong engine ready for a big turbo. But obviously the engine spec would ultimately be dictated by the turbo.
Eventually we decided to go with the HKS GT3037 PRO S Turbo. This turbo is good for over 500bhp and even better it was designed with the SR20DET in mind.

This turbo spools up later than some others due to it being a larger T3 size even though it produces good power, we didn’t mind because we have decided to base our car on a drag/street setup.

The choice of turbo dictated to us that we’d need a very strong and capable engine, Steve one of the senior members of the GTIROC suggested we looked into an engineer who has experience with the SR20DET to do the machining as it is renowned to be a very difficult job and only a select number of engineers can actually get it right. This is when he suggested AGRA engineering to us, an outfit that happened to be in the Scottish Highlands, but their reputation actually speaks for itself.

After careful consideration the following was decided for the engine spec: -
HKS 87mm Pistons
HKS Metal Head Gasket
HKS 264 Cams
HKS Vernier Pulleys
ARP Head Studs
ARP Conrod Bolt Kit
Eagle Steel Conrods
Genuine Nissan Crank *Brand New* (Ours was damaged)
ACL Thrust, Rod and Main Bearings
Brian Crower Double Valve Springs + Titanium Retainers
Greddy Rocker Stoppers
New Nissan Timing Chain Kit
CDF Racing Lightweight Pulley Kit with standard dampers

And the following engineering work to be done: -

Head work

Chemically Cleaned
Skimmed
De Burred
Ported and Polished
3 Angle Valve Grind
Shimmed
Gas Flowed
Crower Valves + Titanium Retainers Fitted
Volume Check Valves

Block work

Chemically Cleaned
Skimmed
Bored to 87 MM to suit Pistons
Honed
Crank Heat Treated (QPQ Process)
OS Giken Twinplate Clutch with Flywheel
Clutch, Crank and Flywheel balanced together

Before we sent the bits off to Agra we came accross a head in the GTIROC. It was for sale and had all the work done already except for uprated valve springs and retainers fitted, we thought it was a bargain and decided to go ahead with purchasing it, here are some pictures of the head: -

Later after closer inspection we found out that the cylinder head wasnt in as good condition as we had thought.

Agra was also given the task to rebuild the engine with all the new parts, this helps to give us the satisfaction that the engine has been put together by experts and we believe they are the best in their field. We asked Agra if they would kindly take pictures along the way so that we could share the whole rebuild with you.

Before sending off to Agra we ensured that we got all the bits needed together and packaged them all into a pallet ready to send off, here is a picture of the day we sent the bits off: -

One of the jobs we asked Agra to do was bore the block ready for some oversized pistons, here is a picture of Agra boring the block: -

Agra also carried out the honing process afterwards, this is a picture of the cylinder block after being honed: -

Here is a picture of the Standard Nissan Crankshaft that we purchased ready for the rebuild: -

After the boring and honing process Agra also got on with heat treating the crankshaft, which we bought brand new from Nissan, it is only the standard one but is more than capable of being the lynch pin of our engine. Here is a picture of Agra doing the polishing part of the QPQ process: -

Notice the black coating left behind by the QPQ process.

The next process that Agra undertook on our engine was the balancing of the bottom end, below is a picture of them undergoing this process, notice the chunks being taken out of the crankshaft: -

Agra have done the work to the bottom end and are now preparing to build the engine, here is a picture of the HKS Pistons with Eagle steel Connecting Rods (Conrods) and ARP conrod bolts: -

Coming soon pictures of Agra fitting the Bryan Crower valve spings and Titanium retainers and also many pictures of them putting the engine back together and of course us putting the engine back in the engine bay.

Here is a very good article on how to build an SR20DET head for anybody interested.