NA MX5 front suspension suitability for hot rod project?

[Phil Bradshaw]

I am helping a friend with hot rod project planning. Car is a Ford Vicky but may take similar approach with a Ford Popular. Chassis will be similar for both cars in that it will be scratch built with a disc braked Toyota live rear axle with custom 5 link set up and coil overs. Thinking of using NA MX5 front end as I like adjustability and well known handling properties. Depending on fit may end up using modifed MX5 front subframe then copying geometry and using factory arms and uprights etc and coil overs. Will use 15x7" 4x100 PCD front wheels.

Engine likely Lexus 1UZ V8 that will sit behind axle line. All up weight likely under 1000kg with similar to factory MX5 front axle loading. Will narrow front and rear suspension to suit and probably convert to suitably narrowed manual steering rack likely from other vehicle to remove bump steer.

Have got alignment info and MX5 chassis dimensions but need to know if there is a factory spec for distance from ground to a chassis or suspension point at factory ride height (front and rear) so I can set chassis up with suspension in factory neutral position at desired ride height and in correct plane to get anti dive etc correct. I have this info for Toyotas (that I normally play with) so hopefully there's similar info available for MX5.

Also advice on simple brake upgrade that will fit within 15" alloy wheels - NB with redrilled rotors? Noting overall performance.

Thanks.

Phil.

[93_Clubman]

Re using an MX5 NA front end, the NA6 factory manual provides the following ride heights & corresponding wheel alignments, along with standard wheel alignment for comparison:

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FWIW, the MX5 books by Yamaguchi quote NA6 ground clearance (laden) as 115mm, while Long's MX5 book quotes NA6 ground clearance as 140mm (NFI), which is presumably unladen given the aforementioned 115mm.

Re brake upgrade, Australian domestic market MX5 NA & NB had three series of brakes: 1989-1993 NA6 (14" rim); 1993-2000 NA8 (14" rim)/NB8A (15" rim); & 2000-2005 NB8B (16" rim)/ C (16" rim)/ D (SE 17" rim). Some, but not all, 15" rims will fit over NB8B/C/D brakes, eg NB8A 15" rim will fit.