GLHS

How many version of the J-spec Turbo engine is there?

I have heard from people, that they produce the same amount of power as American engines.

I was told by a Japanese fellow, who I got my engine from, told me the engine I got is 220 HP.


Now I was thinking they are all the same power rating, but yet, I had some issues I should make known, about the J-spec engine.

First issue was the turbo, it had larger turbine housings VS the American one.

The next issue was the intake was almost 2 inches taller. I verified this against the old intake, I also had to splice about 2 inches into the injection harness, jsut to make the harness reach the injectors.

Next odd thing was the intake had no port for the brake booster, WTF... NO power brakes in Japan???

So anyway, I swaped the engine in, and running the full stock exhaust, I pegged the factory boost guage, right around 2200 rpm.

So I tried this 2.75" exhuast with a main cat on the custom system, and the boost pegged the guage this time, right @ 1800 rpm.

Now I am the first person, to say, not way they are not different engines, but the things that didn't match up leads me to think that the Japanese guy was truthfully when he said " No warranty on race engine".

The question is did Mazda make a Japan only race version of the 13BT?

cblake3

iTrader: (2)

I have never heard of the J-specs having different performance numbers than A-specs. Someone else may know differently, but the two motors/turbos are basically the same with minor differences.

The port for the brake booster is on the passenger side of the upper intake manifold, simply because J spec cars are right hand drive (brake booster is on the opposite side of the engine compartment over there/shorter run).

From what I know about J-spec motors, the guy who gave you this info is full of **it.

GLHS

Should I supply this guy's phone number?

If I did would you guys be mature with him?


He is very hard to understand, being he doesn't speak English very good.

hawk 7

iTrader: (2)

Easy solution, just take your car to a dyno.

biorotary

It's a j-spec (used motor) so it might have some aftermarket parts on it...

if you have an s4 and got an s5, the intake runners are going to be taller...it just is on all s5 turbos...and because they are "taller" your wires may not quite reach the secondary injectors unless you move the harness around (i.e. take it out from under the vac spider)

MtnRacer

Mazda never made a race spec 13bt. The did boost power from a normal 13bt block by playing with the exhaust restrictions and fuel supply(do a search on "Infini") but as far as internals/turbo/intercooler/etc, the blocks are pretty much the same as the Aspec one. It's more likely you go somebody else's old modded 13bt.

Steve

RETed

Power specs should be the same for comparable Zenki/Kouki engines.&nbsp There might be "weird" combinations (i.e. distributor on Zenki, electronic OMP on Zenki, manual OMP on Kouki, etc.) that are not consistent as on US-spec engines.



-Ted

GLHS

The wastegate setup was exactly backwards from the A-spec setup. Is this a S5 engine?


Also the thing about the brake booster, sorry their is no port for the brake booster, trust me I checked and checked, I had to swap the top manifold back to A-spec, to get power assisted brakes again.

You guys have had some good points, about the engine being pre modded. I never thought about that, being the engine was so clean and stock looking, compared to the A-spec.

Besides that, It always seems the Japanese get higher output engines than we get in the same car.

FC Drifter

the only difference between the jap motors and our US montors is one less cat. ive seen S4 and S5 jap engines. they are indentical to the ones we get. like was said above, you got one that was modded.

NZConvertible

That's not the wastegate actuator, it's the twin-scroll actuator, which for some unknown reason is on the oppposite end of the manifold on J-spec engines. It also means it's an S4, not an S5. The pic below might help, it's my RHD car. You can see the metal pipe with a banjo connection that's on the manifold, and has the brake booster hose on it. The metal pipe must be missing, but the treaded hole will be there. Sometimes, but not with the FC. In fact the official power figures for the FC's on this side of the world are 178hp and 196hp for the S4 and S5 respectively, which is a little less the the figures quoted in the US. I doubt there's any real difference though.