RB 25 Dyno tomorrow, few ?'s

[xjon]

Getting my RB 25 series 1 dynoed and tuned tomorrow. I don't know what to tell these guys as far as specs or anything. Would they just know automatically what to do? I don't know if they ever tuned a rb engine before.

Everything is pretty much stock with a few upgrades such as fmic, 3" turbo back. FPR if you count that as an upgrade.

they said they'll tune timing and fuel and give me a before and after run printout. What else can I tell them to tune?

thanks.

[Yellow4g63]

I would just save the money and buy a AFC. You can kinda tune it with the fpr. Save the money buy a AFC and find a forum member with a good wideband an tune it. Then pay $50 for a hp pull an see where your at.

[gprodigy85]

always good to get a baseline dyno though dont you think, otherwise you dont know where you got with the tuning.

[xjon]

That's what I want. A baseline. I just want them to adjust the timing and fuel with CAS and FPR. I also have hesitation at WOT at high RPM's. I also want to know that what I have showing on my RSM is correct as far as the tach settings.

[PANGES]

are you going to get an air/fuel print out along with your dyno?

[xjon]

I hope so. I wouldn't know. This is the first time for me. which is why I am asking these questions.

All I have are printouts of what the idle should be and the timing.

[Joe]

they really cant tune timing, only set the baseline. its all ECU controlled. its always a good idea to get a baseline but its not necessary for your level of modifications.

[PANGES]

if i recall correctly, i think if you get an a/f printout, it costs more but that mite be useful for future refference

[xjon]

This is the first engine that I am getting deeper into other than bolt ons so excuse the lame questions.

Can't/ shouldn't you adjust timing by advancing or retarding it? When I got the engine I removed the CAS to checkout the timing belts and water pump etc. I might not have put it back in the right place. And I don't have the timing light handy so I've never been able to check it. I believe on the 25's you adjust it with the CAS.

When i was messing with the KA I always hear people saying to play with the plug gaps and also the timing (advancing) to get some hp. I've never tried it since I never knew what I was doing.

[JonPowell]

You set the base timing, but the ECU controls it from there. The RB motors arent really "timing tunable" with everything hooked up because once you hook all the sensors up, the ECU starts throwing timing all over. You can advance the timing on the RB, but the ECU will control it from there and if its too far(knocking) the ecu will try to retard it. The timing on the RB motors isnt definate like on a car with a distributor.

[xjon]

Oh, now I'm understanding. Thanks

[Gabe35Coupe]

So what happened at the Dyno/Tuning session Jon? Did they fix your huckup?

[xjon]

good news and bad. Bad news is that they didn't have a fully functional dyno and they thought they fixed it so they tried it on with my car and did one run. Still not fully fixed so it was free. I did get a hp number but no torque number and they do not give A/f numbers.

The hick-up occurs on WOT past 5500 rpms. The dyno guy told me that it was a plug being blown out so I've been running with 5 cylinders at WOT. I asked if it could be the coils but he was very adamant that it was a plug. Which one? He wouldn't tell me for he fears that I would just change or regap the one plug. I will check the coils anyways because I recently changed to NGK Iridiums and even with the stock plugs that it came with it did that also. So he told me to get some copper plugs, 2 step colder, and gap them to .711mm or .028". The gapping seems very extreme for me since all I've read suggest .8-1.0mm gap.

So the graph showed power up to 156hp where they stopped after they felt the "hick-ups".

So any suggestions? I was so bummed out at first but now I am excited since now I know that I could get more power from this engine.

[JonPowell]

could be the "variable cam timing" solenoid not functioning properly....check there....it kicks about 5500RPM

[xjon]

Jon- where is that located and how do I check it?

[JonPowell]

RT side of the engine, just behind the timing cover, above the coolant outlet to the radiator...large brass fitting sticking out of the head 90 degrees. I will check tonight when I get home, I dont have the manual here at work on how to check it....sorry.

I would start by making sure it is plugged in, it has a black connector witha metal wire to keep it in place. If the metal wire is missing or the plug is loose....engine wont run right.

[xjon]

Plugged in tight with the wire. Runs right just when WOT at high rps it has a stutter.

[boost_boy]

If the dynomometer has issues, don't waste your money. Find a unit that's fully functional, so that you'll get a better idea of what your car is really doing and not a half-@$$ picture. It's serious business when you strap your car to rollers because for one you're payinf for the time one way or another and you could very well tear up your stock engine if you have no idea where things are system-wise with your engine/car. And I wouldn't have even mentioned that 156hp reading because that engine does better than that on its sickest day:D . Anyways, don't settle for less when it comes to your expensive investment.

Dee

[JonPowell]

Sounds JUST LIKE the VVT solenoid isnt kicking in....Remind me tonight when I am home(around 6PM EST) and I will check the manual.

[xjon]

Boost boy- he didn't charge me. And he didn't do anything as far as tuning. He pretty much stopped as soon as he felt the car hesitate. Thanks though.

If not too busy at work I will try to remind you. Thanks Powell.

[RBTALLY]

I had a problem with the spark blowing out on my car.... my gap is now down to .14 on high boost and .17 on low boost... I run NGK R5671a-8 plugs.... hope this helps

[boost_boy]

Quote »Boost boy- he didn't charge me.[/quote] Good deal.

Dee