Yeah I tried to get it from the posted link,and the host must of took it down

 

I'll look through my DVDs later. I know its among my booklet

 

You come down for the Homestead meet. It sucks that Alex won't make it though, but I should be ready by then. I just need to install the IC piping, hotside to a .96 and abit of wiring,

 

lets get back on topic


i cant say anything really but

whats your dyno sheet

 

The 12A had fuel injection two years before the 13B.

The reason the 12A was dropped was Mazda had to increase power to keep up with the trend- who wants a mere 100hp sports car. The increase in capacity with the13B resulted in some 8% increase in power. In contrast, manufacturing costs only increased by 2%. Increasing the capacity of a two rotor was the most efficient way for getting another 40-50% increase in rwhp, going 3 rotor would have added 30-35% to engine cost, while the engineers did not think the RX-7 platform could take the installation without major redesigning.

Do not be mislead by the relative power of the USA stock 12A and 13B from 84. The difference was primarily due to marketing decisions rather than engineering potential.

 

Back to the thread question!

On a 12AT with stock turbo and porting I get 220 rwhp and 195 torque. That is my compromise between performance and fuel economy/reliability/safety in a daily driver.

I looked at a wide range of options for legal street use right up to a 695hp 20B.

However, after spending some time researching my driving environment I come up with specs to obtain my optimal 220rwhp. With a 70 mph speed limit any more power would be a waste of money. As it is, if first at the traffic lights, with a sub 13 second car, I can leave other cars way behind without ever going over 3500rpm.

If I entered competitions that would be entirely different.

 

stock 13b-re

 

The biggest difference for me is sound. The 12a produces a much higher pitch annoying tone than a 13b.

 

the 12AT that came in the GT-limited FB was FI...

 

The only possible reason that I can think of that would make a 12A better then a 13B is it's shorter design would mean that it has a shorter eccentric shaft, and since the shaft is shorter, the support bearings will be closer together which means it would deflect less at high RPM/high boost/high power levels which would enable it to make more power then the 13B. I think.

 

Not correct. All the 84 and 85 model SA RX-7s in Japan had the option, for some 250k yen extra, of having the 12AT efi engine from the 82 model Cosmo rather than the 6p 12A [ 27% more power]. These were the GT, GT-X, and SE LTD. For the 85 model there was also a typical Mazda Special Edition when sales were slipping, a base GT with the 12AT, in silver with the optional rear rubber spoiler, saving 140k yen.

 

a mere 100 hp engine. a mere 100 hp engine!!!!!!!


8% outta a hundred is not that much!!!

8 hp

8% outta 150hp
not barely enough. get your math right :P
5 or 4 hp

 

I wonder what the horsepower would be if the rotors were twice the size.?

 

Not certain what your perceived correction is, it is not a logical sequence or arithmetically accurate.

Due to constant other frictions the increase of capacity of 14.1% from the 12A to 13B will only give some extra 8% rwhp. For the USA version 12A that is around 6rwhp, remember it was a detuned 100hp version to meet emission controls, even less powerful than the smaller 10A never mind the 10B with 128hp.

In 84 Mazda were looking for some 40% more power to remain commercially competitive with the 180hp of the Nissan 300ZX. The cheapest/most reliable way at the time was to bring back the 13B which had been around for 12 years, and revamping it with 6p and efi. The new version was also designed when the Gen 2 was on the drawing board. This is why the 12AT with 140hp was not used in the US.

 

exactly, this is what these guys dont understand.... useable horsepower..... key words... my car is useless on the street...

 

amasing... i want you on my payroll, but proabably couldn't afford ya!

 

im cheaper and i can bribe you with cheadder chesse

 

see im being educated already so i can rub it in other peoples facess.

 

I run on Stilton, its got a higher octane when mature. A vintage Cheddar is acceptable in an emergency for that smooth take-off, but Kraft processed should be reserved for civic events.

 

Ha ha ha, so is mine. Thats why I have gone back to a street ported engine and a T66 turbo. I am still running it in at the moment but from what I can tell I have moved my powerband back down the rev range and widened it too.

 

my brother was driving my car today. he has a supercharger on his.

when he floored mine he acted like the pedal was not engaging : (