What size are the Exhaust Bolts that join the Rear Box to the Centre Box.
Mazda Part Number FP13-20-WA4
I have bought new centre and rear boxes and am looking to replace the joining bolts with new ones when fitting.
MX5 Mk2.5 1.8i Sport.
I am not 100% certain but most aftermarket exhaust parts are nut and bolt joined through holes rather than Mazda OE standard which tends to be studs on one part and nuts to fit.
I would expect these to be M10 with 13mm heads and nuts.
Did you buy a fitting kit? If not, nothing to worry about as fittings are mild steel - just measure the holes and get the maximum width to fit holes(M10 = 10mm)
10mm x 17mm af.
Just checked my Mk2 not Mk2.5 and they are as follows
M10 x 40mm long fine pitch of 1.25mm not extra fine at 1.00 mm. Material grade 8.8
Bolts here 6 pack.
https://www.ebay.co.uk/itm/M10-x-1-25p-x-40-FINE-PITCH-HEX-SET-BOLTS-FULL-THREAD-8-8-ZINC-YELLOW-from-3-75/382462023847?hash=item590c8358a7:m:mmlMRdTy9T7nwTjW9XY2DTA
Nuts again M10 x 1.25mm pitch
https://www.ebay.co.uk/itm/Metric-Fine-Pitch-High-Tensile-8-8-Steel-Full-Hex-Nuts-M5-To-M30-Yellow-Clear/112854185059?hash=item1a46a23463:m:meq_GXGg3vYe7Od6CmNXRjA
The measure of the bolt length from the tip to under the bolt head, the length of the bolt head is not included in that length.
If there is plenty clearance to get the nuts and bolts in I would go to 50mm bolts
https://www.ebay.co.uk/itm/M10-x-1-25-METRIC-FINE-PITCH-YELLOW-PASSIVATED-ZINC-HEX-HEAD-BOLTS-SET-SCREWS/122324495007?hash=item1c7b1baa9f:m:mzcTf3cFaJDw25pW-YBXZNA
Big thanks for the quick replies.
I did not get a full fixing kit, just new gaskets.
I have ordered 40mm and 50mm bolts and nuts from the Ebay links.
Thanks.
Just to complete this thread.
New Exhaust fitted and running perfectly.
I bought the exhaust from Carparts4less (sister site of EuroCarParts)
Bolts from Ebay.
Gaskets from MX5-Parts.
Jeff.