Disappointed Dyno

[Gazzasore]

Here is a few pics of mine hope it helps
Along with my intercooler & when Jordy is finnished with my Supercharger
Wammo

 

[Gazzasore]

Its Neils Supercharger Headers www.Rushimports.com.au
Magnaflow X pipe
Lukey Ultraflow Mufflers
2.5 inch Mild steel all the way sounds like a V8 should

 

[WDoherty]

rdm20fan, what are you tuning with, maybe the slpit second controller is not really working well with the ecu. it seems like whatever rdm20fan is using is working well with the ecu for tuning

 

[chrisman]

WDoherty,, rdms car is also using the original ecu--plus an extra injection controller that controls 8 extra injectors-completely independant of the toyota ecu..we are not pulling any timing--but we are adding alot of fuel ONLY when boost comes on--in relation to rpm.. its really quite simple except for plumbing in the eight extra injectors..

i am fairly certain that the factory ecu-in our case- is pulling timming when it senses any detonation..
but we did have a problem with one injector not flowing as much as the rest, causing a lean cylinder--not really unlucky,but a stupid mistake :redface: ,i should have cheked the injectors, after all, they were some used ones i had around..

 

[Lextreme II]

Here is a dyno i did few months ago with 389 bhp with Dynapack at the same psi and stock engine (lowered compression to 8.8:1) Same turbo and same pressure but different number. I think the car have more hp then its being listed.

 

[Lextreme II]

FYI,

The above dyno was with cracked head and water leak into the chamber and the dyno was higher then the built motor......???? HUMMMM???

 

[WDoherty]

That dyno says flywheel corrected power right? Anyway, if you are pulling a degree of timing with every pound of boost thats pulling 24 degrees of timing and rdm20fan is pulling none, so there may be something there. If you question the accuracy of the dyno you might find a local strip that does a street night (this should only cost around $10) that does timing and run the 1/4 mile and get your 1/4 mile trap speed. There are many calculators on the net that will give you approx crank power based on the speed and weight of your car.

 

[rdm20fan]

if you are pulling a degree of timing with every pound of boost thats pulling 24 degrees of timing and rdm20fan is pulling none, so there may be something there.

WDoherty may have hit the nail on the head. And timming is something fairly easy to check.

 

[Pro]

yeah 1 degree retard per psi is overkill - that's 12 deg of retard for that much power - way too much.

 

[Lextreme II]

PLEASE READ ALL DO NOT TAKE OUT OF CONTEXT

A single 2.00" pipe will support 200+hp. 2.25" will support 300+hp. Dual systems double that. Understand that the above are ranges and in fact some have engines making more than the above. The pipe itself is rarely the restriction. As you add transitions and bends and mufflers and catalysts the effective flow SIZE of the system drops.

Twin 2.00" on a stock 1990-1994 1UZFE engine is fine as long as the other variables are done correctly. Using mandrel bends and high flow mufflers (magnaflow, borla, other straight through perforated core mufflers) should be easiest, least expensive and quietest.

Twin 2.25" if you intend to modify your engine past 300hp may be a better choice but requires careful transition design to avoid loss of low RPM response efficiency and torque.

Exhaust is both an art and a science. That is why I recommend copying the stock layout with better mufflers and Y pipes

According to JBrady a single 2.25" would support 300 bhp. That is why our dyno is so low....

 

[cowboy bebop]

Where's those figures come from, because a 2.75" ID downpipe will support 934rwhp. Ask me how I know. : )

Eric

 

[Eels4Ever]

I agree with ya, I've been around a few 2.0l 4cyl turboes (1/2 a 1uz if ya will) and 200 hp is usually made with the stock 2.0" system and some restrictive emissions equipment. I could not comment on 2.25 but i know personally that 2.5 exhaust system is good for upwards of 350hp (or 700 if your considering a v8 )8)8) It would seem to me (unless I'm stupid and not getting this, in which case paint me a picture, I've been known to be a touch slooow) that a dual 2.25" system should be good for between 400 and 700hp. Your dyno was somewhere in the sub 300 range am I correct? If you have 2.25" exhaust that clearly is not the reason for the low dyno in my humble opinion.

 

[cjsupra90]

One thing to remember here guys is that the HP numbers that a particular size pipe will support is for the pipe itself. the type of muffler that you are using becomes another factor here. With straight through mufflers like example Magnaflow's or Dynomax Ultraflo then yes the pipe numbers will pretty much stay the same, but if you are running any type of muffler thats restrictive like a "turbo muffler" or anytype of multi pass muffler like OEM style then that lowers those numbers quite a bit because the muffler is restricting flow regaurdless of what the pipe can flow.

Example here is on my supra. When the turbo went out, I through on a nonturbo exhaust manifold with the 3" ehxaust system that was on the car. Now 3" for a 200hp 3.0l N/A motor should be to large especially using a Magnaflow straight through muffler. The car was way to loud for my taste, so I cut the muffler off and put a cheap 3" Dynomax superturbo muffler on there. Bottom end picked up ever so slightly, nothing to brag about though, but the top end droped off noticably and still had 3" pipe that was supporting 465 RWHP previously.

 

[Lextreme II]

After the minor exhaust mods along with leaning the higher end and decreasing timing from 1 degree per psi to .5 degree per psi. The car is running alot better and would be interested for re-dyno. I also change out the Denso Iridium to a basic two step colder spark plug. I am using NGK6079 with .030" gapping. I might decrease the gapping if needed.

 

[stevechumo]

I agree with ya, I've been around a few 2.0l 4cyl turboes (1/2 a 1uz if ya will) and 200 hp is usually made with the stock 2.0" system and some restrictive emissions equipment. I could not comment on 2.25 but i know personally that 2.5 exhaust system is good for upwards of 350hp (or 700 if your considering a v8 )8)8) It would seem to me (unless I'm stupid and not getting this, in which case paint me a picture, I've been known to be a touch slooow) that a dual 2.25" system should be good for between 400 and 700hp. Your dyno was somewhere in the sub 300 range am I correct? If you have 2.25" exhaust that clearly is not the reason for the low dyno in my humble opinion.

Me too. I've been turbocharging 4 cylinders Honda cars and used only 1 single 2.5" pipe for up to 300 whp. No lagging whatsoever. And for around 200 whp to 250 whp, I only used 2.25" single pipe. Many of you have forgotten to compare the inner diameter of the pipe only, and not the outer diameter. Most of you seem to compare the diameter in general. It's because most stock exhaust systems have very thick wall; therefore, it's not correct to compare between a stock 2" outer diameter with 1.75" inner diameter (or even less) to a custom 2" outer diameter with 1.9" inner diameter. The comparison should be for inside flow.

 

[Toysrme]

There are many, many, many Turbo v6's with 2.5" pipe. Most of the 350z kits are 2.5" turbo back. One of the first ones was running 500bhp on 2.5" pipe.
I wouldn't worry about pipe sizing on custom exhausts. The best exhaust, is no exhaust! After that, a tuned exhaust. After that... It's all comprimizes so s long as it's not restrictive, it's all cool beans!

 

[SC400TT]

rdm20fan, what are you tuning with, maybe the slpit second controller is not really working well with the ecu. it seems like whatever rdm20fan is using is working well with the ecu for tuning

I would say making a statement that "maybe the Split Second unit is not working wel with the ECU" is incorrect. Perhaps much more tuning is needed, but that would not be the fault of Split Second.

The Split Second Piggy back ECU controls both fuel and timing, and is designed to intercept the signals from the engine before they reach the Lex ECU. The timing is reterded in time slots in either micro-seconds or milli-seconds primarily depending upon how much load is placed upon the engine at a particular rpm. These time slots are then represented as percentages of timing retard based upon the numbers placed in the mapping.

If there is a problem with gaining peak power at any given point in the power band, or if you look at the curves on David's Dyno run, you see the many jagged edges instead of a more fluid curve...this is due to the need for much more detailed tuning. Tuning is an art, and should most definitely be done by an experienced, qualified tuner to get the max potential out of your engine.

I would say that you really need to look into your tuning further Dave, especially if everythign else checks out with your setup...

Ryan

 

[Gazzasore]

People here in Aussie go for the Unichip
& have great success
see Peters site
http://www.planetsoarer.com/indexfull.html#ecu

You can get these in the USA

I have one too just not fitted yethttp://www.planet

 

[Toysrme]

The problem with Unichip is that you can't change anything without them doing it, and it's the most expencive line of piggybacks, for no reason.
Which makes it the least desireable piggyback to have, upside of the SAFC line.




If you have money for a Unichip, you have money for an SMT-7, or E-Manage Gold - which will essentually turn a stock ECU into a stand-alone. Or just buy an entry level stand-alone.

 

[WeasyS2S]

Whoa i hate coming in late to these discussions but as soon as i read that ONE thing stood out.

WHOA REATARTED (timing that is)

That is your ecu fighting the piggy back as well...the tune is not looking like its up to snuff at all...

When you are using the ftc are you pulling fuel using it or adding fuel?
This is key to how you should tune your timing using a piggyback.