I went to a local car show today, and there was a flat black '83 with a widebody, roll cage, BP 12a and a Mukuni sidedraft. It was badass, the guy just moved down from Ontario.

Anywho, at the show they had a dyno, anyone could use it, $60 for 3 runs. There was a FC race car there with a N/A 13b with a bridge port, I know it had has turbo rotors in it (why I don't know) a Weber 51 IDA from Racing Beat, RB header, HKS exhaust and MSD ignition. It sounded impressive on the dyno, but the numbers were 106 tqr and 150hp

My question is WTF? that engine stock puts out almost 150.

I'm just really curious as to why it put out such low numbers. What do you think is wrong here

 

poor tuning would be my guess. that and the low-comp rotors. he may have also been using high octane gas because he has a "bride port" motor and doesn't realize that high octane in n/a rotaries kills power.

 

What were the other cars making?

The Turbo rotors in reality don't make much difference.

I wouldn't say that high octane kills power. It's just not needed in an n/a rotary.

 

It wasn't an RX-7 show, there were only 4 Rx-7's there, the wide body FB, 2 FD's and the FC race car. I didn't take my car.

But there was a modified turbo SR20 240sx the guy was hoping to make 350hp and made 199 ha! And there was a skyline with a RB20DET which made 280hp with his boost turned down. Thats the only cars I payed attention to on the dyno.

 

haha the dyno machine lies!

 

Factory numbers are taken at the flywheel.
Stock S4 FC 13B will only put about 120-125hp to the rear wheels.

 

Still, only making 25 HP with a bridge port and a large Weber and other mods. That's just wrong.

I would imagine that with my set up ( Stock port, Weber, header, straight through exhaust) I would gain near 25 HP.

I would imagine that the engine that was dynoed should be making somewhere near the 200hp number.

 

Tuning, tuning, tuning...

 

I didn't take these pics, I got them off of a local car forum, I guy took pics of the car. Here's 2 of the 7's





And the one on the dyno

 

that 150 wheel hp, but even then those are low numbers for a 13b bridgy

 

yep, i agree. must be tuning.

my 13b with the turbo 9.0 comp rotors, street ported with 48 ida and racing beat street header system pushed 168 on the wheels !

 

definatly tuning or a poor motor build or a fubard ignition system or a combo of all of the above

 

Yup bad tunning indeed (or just dyno isn't giving the best numbers neither,

My 12 SP with holley running a/f os like 12s up high did 147rwhp, and 120 something of torque. With my new ITB setup, better ignition, and better A/f ratio, I'm actually aiming close to 165ish at the wheels. Might be too high of an expectation but I don't see why it wouldn't be doable. Also me redoing my exhaust sytem to be all mandrel bent might give me and extra 1/2 a horse power or would probably just equal out the power since I'm adding another muffler in there.

 

i say it's the dyno..steve kan was here earlier this year in vegas and this one guy was getting around 130 with a new rx8...

 

My 12a j-bridge put 205hp to the ground. With the wider powerband RB dual presilencers - not ideal for peak hp but more powerband.

Brad

 

Is it an automatic?

 

It has speed sensors on the wheels reducing power if not all four are at a similar speed. It makes dyno testing difficult.

 

Those "mobil" dyno's are about 10-15 % off sometimes. If its not a "drum" style dyno thats mounted in the floor that both rear wheels sit on, don't wast your money.

 

Look at the dyno thread in this section for more disappointment.

 

it was not the dyno. i was there watched lots of cars on it all day. would say tunning is a big prob it ran like shat at low rpm's i thought.

any way this is there car.....
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/project-fc-race-car-%2A56k-pack-lunch%2A-659398/
and if you read right at the top of there post it reads...... it made 285hp at the flywheel.

allot of this stuff is different on there car now, they changed a bunch of things there self. i don't be leave it ever made 285hp tho. i never seen the sheet saying 285 but i did see the sheet and the runs that made the 150/106