Naturally Aspirated

[Magpie]

During the MX5 plus open day there were a couple of questions regarding my natural aspirated build, mainly regarding the ITB's.

The jenvey manifold at least for the NB tapers from 45mm (1,590 mm2) dia to an ellipse of 30.2 x 49.3 (1,169 mm2) to match the intake port, so yes there is a taper on the manifold.

The Jenvey throttle bodies are not tapered 45mm both ends. However Jenvey do state that the manifold can be taken out to 50mm so if for whatever reason you felt the need you could fit larger throttle bodies.

The main issue still to be resolved is the air box for the ITB's. The current plan is to put an OEM clutch cylinder back on as they are slightly smaller and sit closer to the firewall and then try to fit the Pipercross. However it will almost be impossible to get it off due to space and brake lines, this will even be after the brake lines and prop valve are moved. But thee may not be much need to remove it all the time as the Pipercross has its air filter in an easy to reach location.

If the Pipercross is a no go then it is a custom box and I'm sure Dany will do a work of art.

Notwithstanding the decision where to duct the air from is still to be made. Relocate the coolant overflow, cut the bonnet and put a panel filter on (requires a custom box built) or duct down to the front of the car.

It would be great if Naturally Aspirated had its own section to make a one stop place. I know that miata.net has its own section for naturally aspirated but RHD is much different to LHD and we have our own unique issues.

Anyway one article that I found useful was http://www.importtuner.com/features/0801_impp_itb_setup/viewall.html another useful place was the Jenvey website http://www.compsystems.com.au/index.php/en/ orhttp://www.jenvey.co.uk.

If you have any other links to help out with either ITB's or natural aspirated please post them and or suggestions to help out others.

[Magpie]

A good article/guide for putting Toyota AE101/AE111 ITB's on a MX5, however LHD do not have the space issues we do, but still good info http://clubroadster.net/vb_forum/59-irtb-individual-runner-throttle-bodies/39898-toyota-ae101-ae111-4a-ge-miata-itb-resources.html