Hey guys,

Recently brought another car in from japan, loaded with goodies...
However yesterday when I took it to the dyno to be tuned, it made pretty much no power at all..

Compression is good, makes boost fine (stable 1.3bar), air/fuel is good, timing is good, no ignition break up... but still only makes 200rwkw

After 5000rpm torque falls away, and it just stops making power..

Have replaced and checked tolerances on crank angle sensors, replaced plugs, leads, coils...

 

That's odd! Is there any smoke coming from the exhaust?

 

Yeah, has both me and my tuner very perplexed!

No smoke from exhaust or wastegate

 

How much is 200rwkw converted to horsepower?

 

268 horsepower? maybe? i dunno i think thats it

 

ok i bought a 1993 fd twinturbo rx7 the other day knowing it had a problem so i asked around and in a nut shell when i turn on head lights and ac on and let the car idle it stalls every opinion ive gotten told me it was MAF sensor and im not entirelly sure i was wondering if anyone one else has this problem and im new to forum so i jsut decided to post anywhere pleace email me and let me know. c.lick@comcast.net

 

yup.. 268hp = 200kw

One of my other FDs with similar specs to the one in question(tuned by same tuner), makes 370kw/495hp

 

Thats weird. You have compression, fuel and ignition. Maybe you should contact a local shop. I am interested on what your problem is.

 

so what kind of mods is this car running? 268rwhp isnt that bad for a lightly modded series 7 and up.

and if your running the sequential twin turbo's after 5000rpm losing power usually means the secondary turbo isnt running.

 

Unfortunately its not lightly modded...

Trust TD06-25G
HKS exh manifold
HKS silent power exhaust
HKS 1000cc secondary injectors
HKS in-tank fuel pump
HKS Vmount kit
HKS Fcon Pro ECU
.. amongst other stuff..

 

hows ur AFR? i had an issue just like yours, turns out a harness was loose by my Power FC causing it to richin up after 3500 rpm and i had no power whatsoever. sometimes it comes back but i just shake the harness around a lil bit and it works fine.

 

My time at the dyno was a tuning session, so we got the AFR a consistent 11.4...

I'm going to pull the exhaust and downpipe off tonight and have a look. Maybe the center muffler has collapsed or something

 

Is it possible to have clutch slipping on the dyno? What gear was the pull from?

 

It is possible to have clutch slip on dyno, but this one certainly isnt... very solid ORC clutch, with no slip what so ever.
Run was in 4th gear.

its a hub dyno, so eliminates the option of tyre slip.

A GTR skyline that ran after my car, made 500wkw so dyno certainly wasnt faulty

 

Man thats really weird.... bad/dirty injectors possibly?

 

Possibly - altho AFR is consistent, and the injector duty/times are similar to my other FDs.

I pulled the exhaust off last night and found some sort of aftermarket cat behind one of the underbody shields. Decided its better out than in, so chopped it out. I will tig a straight piece of stainless in its place tonight.

It did seem to be pretty clogged up, so possibly the (or at least a contributing) problem.

 

Removed the aftermarket cat and tigged some straight 3" stainless in its place.
went back to the dyno and ripped out 347rwkw

Needless to say, pretty damn happy

 

damned cats lol

 

thats pretty intense a difference in over 200 hp just from a cat?!

 

Haha damn. I thought I said that before but I guess not....

When I replaced the pre-cat and the cat on my fc, it made a world of difference.

Glad you figured out the simple problem lol