I bought my car used and it seems to have the following modifications:
Cat-Back
Intake

It also has a boost gauge installed and it shows 13 psi. I am wondering why my car is producing so much boost pressure with only these 2 modifications?I raced with couple of stock rx and beat them easily. Any clue as to why my boost pressure is so high?

 

It doesn't have a DP, or Mid-pipe? Does it have boost controller of any kind?

I know you should get spikes with full exhaust but I'm not sure about with only intake and exhaust.

 

No it does not have a dp or midpipe. I dont think so it has any boost controller. BTW how do u know if the car has a boost controller? i mean where should i look for it if it has 1

 

Well if you had a manual boost control you'd be able to see a brass valve. If you had an electronic boost controller you'd see the unit in the cockpit. It's fairly easy to build a DIY boost controller, and while you're working on that replace the vacuum hoses. It's better to be safe than sorry...

You can find more info here: http://www.scuderiaciriani.com/rx7/how-to_turbos.html

 

I know someone running 15 pounds with no mods. Your safe but I recomend a egt or air fuel gage to keep an eye on your engine. Or just buy an afc.