Well, first of all, let me introduce myself here. My name is Matt. Im 21, and I luv my 85 Seven that I recently bought from Rotary Resurrection in Morristown, TN.(thanks Kevin). Anyway, she was thought to have a blown motor but was never tested for unknown reasons. After a quick change of the plugs she fired right up! Now that I've had a chance to get the feel of the car over 4,000 miles I've noticed that she pulls hard(for 100 hp)all the way to 8k(surprises the local rice, lol). Several signs under the hood point to a rebuild at some time in her life, but does the 12a make power that high? Also, she will not idle under 1200-1500k even after carb rebuild and tuning. Any ideas on porting maybe??? She also smokes bad when I let off the throttle at high rpms(6k and up).
Thanks in advance.

 

peak band is 5200-7600 or thereabouts. That being said, there is still power to be had over 8K.

The smoking bad after throttle letoff at high rpms is the sign of leaky oil seals...

http://members.ij.net/mrmazda/cfaqtext.html#SSHIFT

 

Yeah, the powerband kicks in around 4,000 RPM depending on your intake and exhaust set-ups.

For the idleing, most likely just needs tuning.

For the smoking, how many miles are on her?

 

142k

 

Then im gonna have to go with pratch, pretty normal to have smoking with miles like that. Probably the seals.

 

check the fuel system about the idle problem... that's what it was for me
jeff

 

what specifically did you change/fix and what were your symptoms?

 

ive got about 150K on my 12a with a bit of smokin above 5000 when i let off a bit, but it still runs strong ... how much longer would you estimate befor she goes on me?

 

13B power band: weak...there it is... still there... yup... okay dropping off now just before the rev buzzer

12A power band: nothing... nothing... nothing... Holy **** that's cool! Okay, nothing again...

 

not for me, my 12a on the dyno was this.... | nothing....weak......a little better......niiice......NIIIICE....STILL GOING????....8000 rpms still making hp! my car isnt purely stock though but the 12a is all top end pretty much.