Newbie Questions

[adrianreeve]

Hi there, my name’s Adrian, and I plan to build an Exocet G- type with my 11 year old son over the next couple of years. I built a Haynes Roadster a few years ago, selling it complete, but without IVA, so really want to see this one through!

We picked up our donor last week, a 1997 1.8, for £325, and have already pretty much stripped it down ready to remove the body. We’ve sold £500 worth of parts so far, with a lot of bits still to go - it’s amazing what people want to buy! Plan is to strip the subframes down, get the bushes out, powder coat frames and wishbones, then rebuild with IL bushes. New discs and pads, and we’ll rebuild the callipers. Good engine service and belt change, then a lick of paint to improve the looks. I want to use the opportunity to teach my son as much as possible about how the systems in a car work, and get him to do as much of the work as possible. Loom has already been stripped, and now I’m removing all the tape and sheathing, labelling everything and using cable ties to keep it all together, and then I’ll remove what we don’t need when the car is up and running, so I can test after I remove each circuit to make sure everything works ok.

Which brings me to the first of many newbie questions I’m sure - am I best keeping the EGR equipment and charcoal canister, or removing it all? Guessing Mazda put it all there for a reason, but see lots of people do get rid of it all. If I do delete it all, what do I need to do with all the hoses etc., and the various solenoid valves? Also, what does the solenoid valve with the vacuum pipe attached to the FPR do, and do I keep it?

Sorry for the very long first thread, hope someone can help me!

[1055]

The majority of your questions revolve around emissions equipment, and as such is subject to your local jurisdictions stance on it. Here in Connecticut, USA - I have to keep the emissions equipment on the 1990 to get through inspection, but then once its through I can delete it all as cars older than 25 years are no longer tested/emissions exempt.

EGR is as simple as a block off plate and leaving wires loose - though you may (probably) set a MIL. Charcoal canister will absolutely set a check engine light on your 97, OBD II car. the generalized solution for this is to move to an ECM where you can program out the codes.

[snowbird1]

The purpose of the EGR system is to reduce NOx emissions, it does this by adding an inert gas (exhaust) to the intake and reducing combustion temperatures. In theory removing it will let the engine breathe undiluted intake air and improve performance. However, in modern engines the EGR is integrated into the engine management system fueling map and is also used to control ‘pinging’ or pre-ignition under load. On a 40-degree C day in Arizona climbing the 3000’ Davis Dam grade there might be a chance of melting a piston – with a lightweight Exocet in the UK probably not a problem! Bottom line - if IVA and MOT inspections don’t require the emission equipment to be intact you could remove the hard ware and blank everything off and install resistors across the solenoid connectors – the only advantage would be to get rid of some of the under-bonnet clutter.
The same applies to the EVAP system, it is designed to trap raw fuel vapors in the carbon canister then burn them off in the engine via the purge valve, may help stop your garage smelling of petrol.
Fuel pressure regulator does need to be connected – it controls fuel pressure relative to manifold pressure.

[Stewart]

TLDR: in the UK you can pull the charcoal canister and blank the EGR off without any issues or check lights.
It may be worth leaving the EGR fitted for the IVA to help with emissions but I know a lot of road cars get through MOTs without the above fitted.