As with most projects and rebuilds, they all start in the same place, mine was no different. However, this isn’t truely the start of my forever ongoing Z project. I’ve owned this car (my second Z) since 2008 when I purchased it from a former member. For the first 5 or 6 years I did the usual mods with suspension parts and basic bolt ons. For reasons unknown, whilst running stock boost, piston 5 cracked a ring land during a track day at Castle Coombe. A forged build and a remap later all was well until a sunny October’s day 2013 at Bruntingthorpe killed that engine with what at the time was a suspected head gasket failure at 181mph..... And this is where I shall start my journal.

 

The Z was stored off the road from Oct 2013 until March 2015. I’d had a major knee operation at the beginning of 2015 which meant I was going to be off work for 6 months. I’d saved up enough to start thinking about a parts list to rebuild her and frankly, after a couple of months of staring at the same 4 walls, I was going stir crazy! I employed the help of a good friend and decided to pull the engine and see what was what.... just a head gasket my arse!

 

March 2015

Problem 1: It turns out stainless steel, exhaust wraps and condensation don’t mix well

 

Before I’d even got the engine out, a new set of downpipes was added to this list. These AMS items were only 2 years old, so I was far from impressed! I contacted the retailer and after a bit of tooing and froing I secured myself a set of replacements for free... how long they will last, only time will tell!

Well I was hoping to give a little update saying that I’ve added a set of camshafts to the spec of my engine so I’m able to take full advantage of my CNC ported head, CNC ported lower Plenum and SuperTech valvetrain......

 

However, no amount of Man Maths I do can generate another £1500 to go into this build. So for the mean time, I’m having the heads machined for extra lobe clearance, so whenever I can afford to update my cams, they can drop in without the need to remove the heads again for further machining

 

A little gutted, but hey, cant always have everything our way!

Edited January 15, 20196 yr by nickz32

What cams were you hoping to use?

What cams were you hoping to use?

 

EPR Genesis 1 cams.... 272degree @ 10.2mm lift

EPR Genesis 1 cams.... 272degree @ 10.2mm lift

 

Why do EPR want your core camshafts?

Why do EPR want your core camshafts?

 

They do?

Edited January 15, 20196 yr by nickz32

Come on Nick keep up!

 

http://epracing.net/products-page/valve-train-components/vg30dett/

I was going to guess they were regrinds, but that doesn’t make sense as regrinds usually have a reduced base circle, which the EPR one don’t (they retain the OE base circle)

I wonder if they are welding material onto the lobs which are then ground to the new profiles?

Quite possible, and they’re then “fully hardened” with some form of hardening process?

Yes, I've seen pretty much the same process applied to crankshaft big ends to increase the stroke.

As and when I do change cams, it’ll coincide with changing to adjustable exhaust pulleys, larger TB’s and extrude honing the OE upper Plenum.... but that’s probably some way off. There’s some chassis based “madifications” that are further up my “to do” list

Edited January 15, 20196 yr by nickz32
Spelling....ish

There’s some chassis base madificstion that are further up my “to do” list

 

With the mods you are undertaking "madificstion" seems entirely appropriate!

Hahahaha..... should have put my glasses back on before typing that :lol:

I always thought camshaft reprofiling was the norm, adding material and profiling it down to the desired specification.

You can reprofile a cam by removing material from the existing lobs but it can increase the stress levels and make

it more difficult for the followers to keep in contact with the profile especially at high revs. Starting with a blank or

building up the lobs can give a new profile with lower stress and easier to follow at high revs.

A local company to me that build engines, also specialise in porting and head work. I had a camshaft from an Uno Turbo(!) reprofiled by them about 20 years ago and the owner showed me the process. He was very knowledgeable and gave me a little tour of the operation. At the time he used to do all the camshaft profiling and head work for Piper Cams which was quite lucrative and when I ordered a Piper cam and given a local address for the core, I thought I’d check it out.

 

Seemingly the company is still going, I wonder if using a local company to do the work to your specification in the future would work out more cost effective?

It’s can certainly be a consideration...... although Piper cams were never regarded as top quality products

You can reprofile a cam by removing material from the existing lobs but it can increase the stress levels and make

it more difficult for the followers to keep in contact with the profile especially at high revs. Starting with a blank or

building up the lobs can give a new profile with lower stress and easier to follow at high revs.

 

From Mitch

From Mitch [ATTACH=CONFIG]115832[/ATTACH]

 

I thought that was just the norm, grinding the stock cam without adding meat and then just adjusting the clearances to suit is the bargain basement way!

I thought that was just the norm, grinding the stock cam without adding meat and then just adjusting the clearances to suit is the bargain basement way!

 

Which is precisely what JWT do, just starting with fresh cores

Whoops

 

A little EPR update. Main caps have been bored and honed. Now it’s time for the cylinders to get the same treatment

 

Whoops

 

In his defense My Lord - it was late, his wife had gone to bed and he had a couple of drinks.

 

[ATTACH=CONFIG]115839[/ATTACH]

A little EPR update. Main caps have been bored and honed. Now it’s time for the cylinders to get the same treatment]

 

Great to see the correct technique using Torque plates for the cylinder bores.