I got the hondata system a few weeks ago, and got the a/f ratios pretty much tuned on the dyno yesterday.


one run is what we ended with
the other is the run we started off with. a baseline prelude map.

i'm running a p28 ecu, i was using a jdm p72 ecu, but it went crazy with the software.

I'm happy i got the hondata, but i'm still trying to get my peak #s up. Everything on my car runs well, so i have no idea what could be wrong. My ignition maps are about 2-4degrees from NA preludes in high rpm range. I have a 2.5" exhaust system as well. Can anyone offer any insight on what i could do to get my #'s higher? We didn't get a chance to play w/ the cam timing, so that could give me some good gains. I also think that my turbo might be trimmed wrong, but i can't tell since i don't know the exact specs of it still.

heres a dyno from before turbo and after. This was w/ boltons + type s cams.






[Modified by Purelude, 10:10 AM 7/20/2001]

 

Your chart looks good, but we will need more information on your set up, such as boost pressure, turbo size, injector size, etc. From what I can tell, you picked up 20 hp and 13 ft/lbs of torque. How is the drivability, and does it feel considerably faster than before?

 

whoops, sorry!

Hondata stage 2 + boost
440cc injectors - injectors were running 50% duty cycle
7psi, avc-r controlled
drag gen2 kit w/ t3/t4

drivability is great w/ the system. Transition from vac to boost is a lot better, i had the missing link before, and it seems like boost just responds faster and smoother. My boost gauge used to stop at the "0" mark for a little bit, then go into positive pressure, now it flows freely through it. I like running stock fuel pressures, awhile ago i had one of my fpr lines blow off and i leaked 1/2 tank of gas. A freak accident, but something that will most likely never happen again.


[Modified by Purelude, 10:27 AM 7/20/2001]

 

those look like good numbers to me for that amount of boost. You're not even close to the sweet spot of that turbo yet, with raised boost you will see higher hp/psi gains. But for now, your a/f's are right where they need to be, so maybe some tuning of the sprockets could gain you some power higher in the RPM band. But I'd be damn happy with those torque numbers

 

Doesn't look too shabby... but, I thought one of the better features of Hondata was to be able to turn the boost up farther then 6 or 7 psi, but more like 8-10psi. Or is that stage 3+boost and beyond?

Why did you decide on stage 2 and not something higher?

 

Hondata allows you to get a better running engine, yes, and i suppose you could turn up the boost safely, but i'm scared! heh, i don't know how much my engine can handle, and 7psi is pretty safe now. I guess you could turn it up, but i don' tknow how that would affect things long term.

I only got a stage2 + boost because i did not want the full throttle shift, or need it. I also don' tneed the stage 4 because my local dyno shop has a stage 4 and can burn me all the chips i want. I would only change settings on the dyno, i wouldnt think of doing it without one.

 

If those injectors are maxing at 50% duty you obviously have room to increase your boost with a good margin for error. Sounds like its time to push it a little.

 

You're fuel is handled well and you didn't mention any detonation, so turn the boost up

 

Im wondering what the hp numbers are going to do with the boost around 11 or so...i saw one chart from import review that showed it gained 60 hp and didnt even take it all the way to redline... https://honda-tech.com/zerothread?id=46879 Maybe our motors just like the higher boost?

 

it seems like a straight t4 works good....in theory, it's sound, higher peak #'s...

maybe we're running out of steam on top end..


[Modified by Purelude, 3:39 PM 7/20/2001]

 

I think it was turbolude that brought it to my attention that the t3 turbine/housings may be too small for our ludes. I am looking for a way to measure timing during runs. I suspect our ecus are pulling timing in the upper rpms. It is just a guess, but it seems sensible that if the IAT senses high intake temps, it would retard timing to reduce the risk of detonation. And, all of us drag turbo owners know that our ICs are only 2" wide and among the smallest of the turbo prelude kits available. On my first dyno run, I felt the piping to the TB and it was cool to the touch. Lately, it is rather hot, seems like the same temps as the turbo outlet piping. I can fool the ecu into seeing cooler temps, but I need to dyno it to see any differences...... Anybody know where I can get a Blitz power meter for @ $280?

 

Yes, a T4 might be a better match for that engine, but you will get quite some lag at first. If you want more hp for something cheaper than swapping out to a T4, then change your exhaust from 2.5" to a 3.0". Also, turn up that boost boy! Your fuel looks like it has plenty of room to work with, so step up that boost and richen it up accordinly!

 

im sorry.... did you say you were only makeing 214hp from a turbo at 7psi? doesnt that seem a bit low??

 

looking at your graph it looks like the torque hits a wall at 5200 or so and just plummets. I would think that your turbo wouldn't be running out of steam that soon. What sive turbo came with your kit? I asume that it is the same turbo that comes in the GSR kits, and if so I wouldn't thinkt hat the problem would lie with the turbo. I think we can also discount the timing in your case, as you can control that with the Hondata. same goes for fuel. What do you have your VTEC set at? Possibly 5200-5300 rpms?

 

PureLude where did you purchase your Hondata system? Also what did you do to the secondary intake runners since the P28 does not control them?

Cheers

 

Strng1dah, I think most turbo dynos with a constant boost setting has torque peak in the mid rpm range. It is probably due to full boost pressure and the time the cams are kept open the longest. If we can have the boost rise with rpm to get a perfectly flat torque curve (flat curve, get it...), we would be GODly turbo tuners. I think that is what those Blitz boost controllers and power meters do, adjust boost according to speed or rpm or something.




[Modified by G, 5:01 PM 7/21/2001]

 

If you decide to go straight T4 get an AR.40 or .48 housing for street duty. If you are gonna see major track time get the Tang AR.50. Use an O-trim ex blade. The AR.40 housing is a Garret Japan made item for HKS.

 

I know that the torque peaks in the midrange. It just seems that it falls off VERY quickly. I would expect the torque to stay higher for a little longer. But then again I have NO experiences with H22s so that may just be the way they are under boost.

 

Well, I think the H stands for headache when it comes to tuning them with aftermarket turbos. I was satisfied with my first dyno, but I feel there is room for improvement...... Have you guys read up on the Zip EBL for the JRSC? It may help us non-standalone turbos.....

 

Yea the #s are kinda low, but its what i got to work with at the moment.

 

vtec is set at 5500 rpm, any lower and we get a dip pin #'s.

 

I went to NIRA this weekend to watch my friends run and got to do alot of thinking since I had no car to run. Lets see here- the fuel isnt a factor since we have many good a/f graphs with low hp, ignition timing isnt a factor, well i believe purelude proved that, valve timing is a pretty big factor, atleast for me, that freed up 20 hp...what else, my compression is great, 205 accross the board...While i was at NIRA i decided i would ask someone that might now a litte about h22a turbos...Stephen Papadakis crew...anyhow, all they had to say was that every motor is different and to try leaning the fuel out more and to do a leakdown test to see if im getting blow by...i am going to go ahead and check out the leakdown test just incase, even though my compression numbers are so high....Anyhow, my latest thoughts are the exuast manifold...Maybe drag didnt put enough effort into the Gen II kits and it is causing major problems for us...The only thing is that it would be a pain in the *** to switch manifolds because of how everything fits...ic, wastegate, turbo....so the only thing i can think is to bore out the drag manifold..

One more question...who here is making good power with a drag manifold and is anyone not making power with the fmax manifold?

By the way, i saw a type r with hondata running 7lbs hit a 12.4 today...aint that some ****.

 

I kinda wondered about the design of the Drag manifold as well. In theory, it has a good layout. Tubular design and runners that aren't too big and the wastegate is in a very good place. Take a look at some V8 turbo manifolds if you think the Prelude Drag manifold is odd. They are crazy looking, but still work. In any case, I can't see the Drag manifold being the sole power killer on the dyno. The manifold might be less efficient than possible, but once boost is built up, 7 pounds of boost is 7 pounds of boost.

Valve timing might be something H22s need to play with. I have heard some guys with SC'ed Type Rs lower their vtec crossover to 2500 rpms.

I need to dyno my H23 sometime soon, if I can get a decent hp number, then valve timing of the H22 might be a big factor. $145 per hour is nuts for dyno time here though.


[Modified by Inlinefour, 1:08 PM 7/23/2001]

 

With regards to turning the boost up to make more power remember that the engine has stock internals. The prelude pistons are particularly weak and the rings lands will crack from the cylinder pressure very easily.

 

as far as i know, us ludes are the only one with this type of manifold...what manifold will allow me to use the ic piping that came with the drag kit and wastegate


[Modified by Turbolude, 3:32 PM 7/23/2001]