What's goin' on folks. I'm new to the forums and just makin' my first post. I'm totally new to rx 7's and just bought one a couple of weeks ago. I am also new to turbo charged cars. I just wanted to know what is boost spike. My fd is fitted with an HKS exhaust, intake, and blow off valve. I was told to watch out for boost spike, but I don't know what it actually is

 

Basically, a spike is just as it sounds, the boost shoots up, then settles back down. Creep means that the boost doesn't shoot up as fast as a spike, but it doesn't settle down as the wastegate can't control the flow.

If its a spike, the boost controller (Profec B Spec S can be a good option)might help solve the problem, otherwise if its a creep the boost controller wont do jack for you. (have to port wastegate to solve the creep issue)

You can safely run bolt ons with your stock ECU as long as your limting your boost at 10psi.

 

Do you have a boost gauge or other direct readout? Usually, a 10-8-10 boost pattern being normal, a boost spike occurs right after the 8 for a split second, like 10-8-12-10. When that spike goes over 11-12psi, you need to lay off the boost until it's fixed.

Dave

 

Where in VA are you? There's tons of local FD owners who can / would help you out with any questions you may have. Try posting over in the NE RX-7 forum.

 

Im in the Hampton area. When I look at my boost gauge, it's only going to 6psi. I've read that it should be boosting at 10psi. What could be the problem. I've heard that I might have a vacuum leak and that if I did, I would be hearing a "wooshing" sound, but I don't. All I hear is the blow-off valve. And also, sometimes when I'm driving normal, I'll see that my boost gauge is reading into the negatives. Is this normal? I don't know much about turbos obviously.

 

yeah vacuum is read when you are not applying gas. You would only hear a "whoosing" noise if it was a really big vacuum leak, you just have a boost leak, i'm guessing your running seq...I'm not a expert there, but that should at least get you started

 

Whats running seq? If I do have a boost leak, how can I actually verify it and what can I do to correct the problem?