My center iron Is torched.. standard 3B intake ports. what are the downside of installing a S3 tall port center iron and using the stock repu medium sized 3B end and front plates? Im going to use brand new gsl-se housings , so the engine breathes a little bit better vs the stock small exhaust ports om the repu housings...

will the bigger primary center runners be a disadvantage on low rpm?

im not looking to build a racing engine.. just a propper old school cruiser thanks

 

i don't think you have anything to worry about if you're leaving the port stock.

are you running the stock Hitachi, or something else?

 

hi. im running RB intake and edelbrock 600 CFM. but i think i will convert to weber 48 ore holley efi

 

The 3b plate made more torque down low as the air was faster into the engine. It’s probably not noticeable unless you were to dyno, and even then probably only a very small change.

but there’s a reason the trucks came with 3b (short port) intermediate irons, and not the r5 (tall port) intermediate that was available on both the rx4 and rx5 of the time.