My rx7 fd has a blown engine. I don't know much about engines but do i need a new engine or can blown engines be rebuilt?

 

blown engines can be rebuilt assuming your housings were not irreperably damaged by the blown seal.

Out of curiosity, how do you know your motor is blown?

 

when i bought the car the previous owner said it had a blown engine

 

a lot of problems are misdiagnosed as blown engines. There's been a LOT of money spent on new motors and the problem remained.

Does the car start? if so, how does it idle? Have you had a compression test done? is it using stock sequential twins?

 

the car won't start, it has stock sequential twin turbos and i havent done a compression test.

 

I'd say go to http://www.fd3s.net and learn how to do a compression test, then come back with the numbers. good compression is 80-100 on all 6 faces. If you don't want to/have the time to do a compression test, you can also pull the feul pump relay and pull the spark plugs, then slowly crank the motor and listen. if you get stree strong wooshes, then your seals are fine, if you get 1 strong woosh and 2 soft wooshes, then you have a blown apex seal.

 

I think those numbers are realtively few, actually

the tell-tale shaking, low power, low vacuum....dead give-aways....and the sinking feeling that you just lost your car for several months (or a year in my case) and thousands of dollars

get a wideband, an aftermarket regulator, and a fuel pressure gauge (and the Supra pump if you don't already have it)...mandatory upgrades on these cars

 

that sounds like you cracked a couple vac lines to me

 

the next best thing to a compression test: look at the vacuum at idle on your boost gauge. if you're pulling like 10 inches of mercury at 900ish rpm on a stock motor, and the gauge is oscillating back and forth (like from 9 inches to 10 inches to 9 inches etc) then you probably have a cracked seal and a blown motor.

 

I heard that they build the 13B-REW's form the front-back??? instead of tha back to the front like most 13B's?!?

 

Um, make sure your MAP sensor is connected. Mine popped off the other day and I thought my motor popped

 

i had a vacuum line from a turbo actuator rip a couple days ago and i though my engine was done... luckily the hose poked out nice n' easy to see so i knew what the problem was.