1angrychainsaw

As the title states, what are some ways of telling? I just bought the car (non running) and plan on rebuilding the motor myself.

lduley

iTrader: (1)

you'll know when you tear it apart and look at pictures of port jobs

it impossible to know if it is already until you tear it out and apart. Even if it isn't ported, now will be the time to do it

diabolical1

iTrader: (3)

welcome to the board.

pulling the engine apart is the BEST way to see what you have. there are other ways to get information in engines that remain assembled, but depending on who did the work, it may or may not be conclusive. depending on what car/engine you have, there are photos of stock and modified ports in the sticky'd porting thread. it's a quick and decently comprehensive reference to use after disassembly.

jonahs_rx7

post pics when the motor is torn apart. i bet someone on here could tell you a ruff idea of what you have

kylemo

iTrader: (8)

I was also wondering the same thing. Would a compression test indicate any porting that was done? Maybe a small increase/decrease in CR? I was curious about mine as well because I was going to maybe swap it for 'newer' jdm engine but I might just rebuild if the port work was already done.....

diabolical1

iTrader: (3)

technically, compression ratio should not be affected by porting because neither chamber volume nor the rotor recess are being changed by the port work.

kylemo

iTrader: (8)

That makes sense, I thought that may be thes case, was just curious. Guess it would affect the overlap/timing more than CR?

1angrychainsaw

I will once I get the engine pulled. The weather and my schedule are definitely not cooperating.

diabolical1

iTrader: (3)

precisely.

jdaily87

So, what would some of the methods hinted at earlier that might let someone determine whether or not your engine might have been ported? I ask because my recently bought 12a FB is making me wonder if it has, for a couple of reasons.

Sgtblue

iTrader: (16)

Pulling the exhaust manifold off and you might be able to see evidence of exhaust porting.