Been reading up on my mazda history. I came across a articule about racing cosmo sports (110S) in the "Marathon de la Route", 84 hours at Nürburgring, 1968 . They were running 10A race engine , nothing to brag about there but they had peripheral and side intake ports. i was like wtf .more searching prove that is was true .



Any ideas on how it was done or pic of the intake design ? It use a webber type carburetor and a port switching shutter valve in the intake. Tried to search for pictures about it but none came up.



You guys seen any around ? Any help here ?



http://www.speedarena.com/news/publish/fea...icle_3903.shtml

 

I think the 10A was like webbers these days. As you drive off the side ports are doing all the work, but once you put your foot down the secondries open being P Port to give that extra bit of air/fuel to the motor for that extra power.



That's my 2 cents.

 

thats what i am thinking too but i was wondering how did they do it ? I have read about dual port set-ups on this forum . Street port and peripheral port on the same engine but it was never ran both at the same time . Cause you had to change the manifold for the diffrent ports , so one street port manifold for the road and a Peripheral port for track . This cosmo had both at the same time .

 

you'll notice they didnt use that setup again, ever. the reason: race car doesnt need the low end.



scoot uses it now (or used it a couple years ago) in their speed record car

 

True that , race car does not need low end . But we drive cars in the real world where the low end is important too. do you have any pic or information about the intake design on the Scoot's car ?

 

this SAE paper has informarion on the combination port :



http://www.thecarricos.com/ACRE/Documents/...tech84-7-11.pdf



they choose PP's for the exta 10PS over the combination, however the fuel economy and power potential looks good for a street car.

 

i assume it a partial P-port here's a pic

 

Wow...great articule. thanks man.nice reading material.

 

That was a great read. Thanks for making me a smarter person. Now off to the porting bench I go. I have an intake manifold to improve.

 

eventhought i did not know a while ago that mazda used such a setup i have decided on my motor to go with a side and pport but not a partial.