Crazy peripheral port if I remember correctly. Considering it didn't produce its maximum horsepower till over 9000rpm, apparently it was a dog to drive under 5000rpm. I'm sure the Mazda freaks will correct me.
It's 1986 or 87?..... I'm a teenager with my first RX-3. I was told visiting a well known Group-C rotary racer in the western suburbs of SYD that assisted the Mazda race team from time to time. Moffat was looking for more power from the 13B-PP engines. His engines would arrive from Japan ready made as an MFR crate motor good for 310hp, Super reliable due to conservative PP design but Moffat wanted more. This established rotary racer was squeezing 320hp from his 13B-PP with more radical porting BUT less reliable. Moffat didn't care about reliability for the ATCC rounds. So he scored some (320hp) engines & this "Group-C racer" got himself into the inner circles of the Mazda Factory race team for 83-84? After the (disastrous) decision to kill Group-C for 1985, the Moffat cars & parts started getting sold off. The "HOLINGER 6-SPEED"......... Moffat sold the 6-Speed for $7000. Quote "$1000 for every gear including reverse". I forget whom too, it's been 35yr since I'm recalling all this.......lol This man (in 1986/7) at his shop actually had some Moffat Mazda starter motors & doors........ All Aluminium. Super light compared to OEM with him telling me. The starters & Aluminium flywheel were only good for 100? starts before the aluminium teeth wore out apparently Horsley knew they couldn't squeeze any extra power from the engine. Mechanical EFI & 13B-PP was limited to 320hp in the 80's, unless you had an F1 type budget for the virgin EFI systems that were being installed into F1 cars in 80-82. Note; some F1 teams still used mechanical injection until the mid 80's. So F1 budget EFI systems were prohibitive due to $$$. Even the mechanical injection Mazda had to make available in 1983 was a crazy $10k & beyond the budget of 90% of the Mazda racers. So they went the other way & reduced weight. The aluminium doors that I picked up where light as a feather. The starter motor was uncanny in it's lightness & the one I held was already worn, perhaps a surplus from the Group-C era just a few short years prior, but a marvel none-the less
Moffat history.......... Few know this...... After Group-A kicked in for 1985. The SA-series RX-7 was no longer competitive without the 13B-PP engine. Mazda USA had the 13B-RESI engine in the series-3 (84-85) RX-7 but Group-A regs limited it's power to 200hp approx Mazda Japan had the HB-series Cosmo (929 in AUS) with 12A-T option that was eligible for Group-A racing. Horsley & team imported a JDM 12A-T Cosmo in 1984 & proceeded to test it's viability for the 1985 season. Most they could squeeze was around 250hp with the boost wound right up but............. Like the Nisan turbo Bluebird, there was NO intercooler & the turbo simply could not flow the required power without melting. Note; the 12A-T option came in 1982 for the HB Cosmo was the 1st turbo rotary ever. When developed in 80-81, the concept of intercooling was not yet accepted across the board. Their 2nd turbo rotary in 1986 did have intercooling The Mazda AUS team needed to get the Cosmo to be quicker than the Group-C RX-7 but it's heavier weight & reduced power meant the 12A-T Cosmo was no match. The FC-series RX-7 was scheduled for 1986 with 13B-T & intercooler but the rear seat volume regulated it out of Group-A thus the whole team & future was abandoned & you all know Moffat sat in the commentary box for Bathurst 1985..... BTW, the HB Cosmo coupe looked similar to the R30 Skyline. On Japanese streets, the 12A-T Cosmo coupe vs the SR20 from the Skyline was a competitive match.
That's what I've heard too. Haven't confirmed it though. I heard it also runs the illegal 6 speed gearbox as that's what Moffat ran back in the day, but again not confirmed
