This is a two question topic.

First off let me explain that my FD never came with an exhaust straight from the block back. So I am putting the exhaust together on my own. And yes I did a search!

The parts I plan to install are:

Downpipe, highflow cat, catback exhaust, all aftermarket of course.

I originally wanted a midpipe, but found that to be too problematic and expensive, from what almost all experienced members would state.

Anyhow like the topic says can I controll boost safely to 9-10 psi with a boost controller for the above mods, w/o fuel upgrades. Mind you this would be temporary until I decide on an ecu within the next couple of months, and then I'll crank her up to about 12-13.

My second question which has been lingering in the back of my mind, which I do not intend to do, but have to satisfy getting it answered is with a full exhaust dp, mp, cb, and the rx7 never seeing above 4k revolutions would I have to worry about detonation, this of course w/o fuel mods.

 

for your first question... you'll be fine at 10 psi with the above mods. for the second question, detonation ahs little to do with rpms and a lot to do with how lean your running. you can still overboost and run lean at less than 4k rpms . if you add boost control to your second list, then it is possible.

 

moehler is 100% correct, you'll be able to maintain 10 psi with a boost controller. Also, many people have blown their engines at speeds below 4k rpm, usually in 4th or 5th on the highway where you can hit 15 psi below 3k rpm....

Additionally, what would be the point of running a midpipe only below 4k rpm. Dyno testing has proven that a high-flow cat makes more power than a midpipe until about 4500-5000 rpm.

 

Thanks for the info guys. Well the point I guess for me is to be able to get it rolling, but safely.

I guess the plus of the cat is that it probably retains more torque then a midpipe, well at least in a non-piston car, dunno bout the rotaries.