Went to the dyno today and it sucked. Help please.
 

I went to the dyno today and was highly dissaspointed. I have a turbo Prelude pushing 10 pounds and this is what I got.....
[img width=600]http://i6.photobucket.com/albums/y215/ihaveanose/Myshittydynoedit.jpg[/img]
The power cuts off right at Vtec and the curve is all shitty. Any ideas? Thanks for the help.

The turbo setup is

T3/T4
10 psi wastegate
2.5" dumptube
3" exhaust
2 step colder plugs gapped to .030
6" intercooler
Stock internals

Well I thought my plugs were gapped at .030 but I was just informed my dad went and ungapped them to see if i would notice, because he thought they didn't needed to gapped when they are 2 steps colder. (He doesn't understand the whole concept of why they need to be gapped)

But anyways I regapped them and it ran smoother but still has that dip in VTEC. Not as drastic but it still dips. Dammit my dad owes me money because I wasted it at the dyno.

pics resized :P

Re: Went to the dyno today and it sucked. Help please.
 

what type of fuel management?

Re: Went to the dyno today and it sucked. Help please.
 

Uberdata

Re: Went to the dyno today and it sucked. Help please.
 

disable your iab's

Re: Went to the dyno today and it sucked. Help please.
 

What does that stand for?

Re: Went to the dyno today and it sucked. Help please.
 

Move your VTEC engagement rpm higher to get rid of that big dip. The big dip is probably from your intake velocity dropping when the motor switches to the big cam profile.

It also looks like you are getting some ignition breakup judging from the graph's spiking. Hard to tell since I dont know how much smoothing the dyno software is using.

How much timing are you pulling for each pound of boost? With 2 step colder plugs you shouldn't have to pull too much timing as long as your AFR's are good.

Re: Went to the dyno today and it sucked. Help please.
 

Well I think Matt(sohc_mshue) and I are figuring it out. The timing changes greatly right there. His questions is if the dumptube is routed into the downpipe right where the bend off the turbo is, will it create exhaust turbulence? Because that is how mine is setup.

But I asked Anthony(CCA) who made my kit including dumptube and downpipe if that would be a problem and he said it didn't seem like a problem, he has seen it done like that plenty of times. More info here....
http://www.honda-tech.com/zerothread?id=1245726

Re: Went to the dyno today and it sucked. Help please.
 

This is the dumptube into downpipe that Matt thinks is causing exhaust turbulence

Attachment 38176

Re: Went to the dyno today and it sucked. Help please.
 

lol, no man, its not causing exhaust turbulance, and even if it is, its after the turbo. AS long as therss no back pressure, exhaust flow disruption after the turbo does didily squat.

Re: Went to the dyno today and it sucked. Help please.
 

Anymore ideas? Everyone is saying ignition but Matt thinks it is something else(I have no idea).

Re: Went to the dyno today and it sucked. Help please.
 

what size T3/4 is it and how much boost did ur boost gauge read?
did you check compression? :-X

Re: Went to the dyno today and it sucked. Help please.
 

No I didn't check the compression, I don't have a checker thing. But the turbo size is a/r .48 and 60 trim

Re: Went to the dyno today and it sucked. Help please.
 

vtec is too early, change it to 6k and re-try. you can see the "small" cam is still making power. make the x-over right where they make the same power.

Re: Went to the dyno today and it sucked. Help please.
 

send your uber map to bigg_body_benz@yahoo.com

I'll have a look over it when i get home. That thing is gonna blow soon if u don't fix that power spiking immediately. I'm kinda suprised it lasted through that pull judging from the dyno. Did you wideband tune at all?

Re: Went to the dyno today and it sucked. Help please.
 

Yes I did wideband tune it, well not me personally, my tuner did. Contact sohc_mshue on here he is my tuner and has my maps.

Re: Went to the dyno today and it sucked. Help please.
 

thats definatly an ignition problem. same as people said on honda-tech. ---- needs to be cleaned out yO!!. thats where its fucked up

http://www.we-todd-did-racing.com/we...MXk1NDE%3D.jpg

Re: Went to the dyno today and it sucked. Help please.
 

4bangers like back pressure.
your vtec is opeining to soon causing the high velocity to drop off to soon.


that timing map listed above is kinda retarded in my opinion. when your motor is spinning at 8k rpm the timing needs to be advanced more than 20*

Re: Went to the dyno today and it sucked. Help please.
 

::) Wrong and wrong.

You never want back pressure behind a turbo. Period. Don't ------ mis-information.

Re: Went to the dyno today and it sucked. Help please.
 

At 10psi you probably don't need plugs are two steps colder than stock.

What kinda A/F ratio's were you getting on the pull, I can't tell from the picture you posted, but it looks like it is pig rich.

Pig rich + shitty plugs = shitty combustion

Re: Went to the dyno today and it sucked. Help please.
 

It was actually real lean, like 12. But tommorow I'm going to get new wires, and go get Matt to retune it, I'm going to bring all this info from honda-tech and hmt with me to check everything. Thanks for all the help, I'll let you know how it goes?

Re: Went to the dyno today and it sucked. Help please.
 

i think you're the one who is misinformed, buddy. backpressure in the exhaust system of a turbo car, especially one with a small 4 cylinder engine, is very valuable in spooling a big turbo. think about it, when not in boost, the system acts like a n/a vehicle. i'm sure you aren't going to argue that on a non aspirated vehicle that overly large exhaust piping that eliminates backpressure is good for torque gains.

Re: Went to the dyno today and it sucked. Help please.
 

No.

If you put any resistance (backpressure) on the turbine, this is going to slow the rate at which it can spool. Go read some basic books on turbocharger theory. Don't even try to associate N/A cars with Turbo. You are confusing yourself and everyone else.

Re: Went to the dyno today and it sucked. Help please.
 

Actually you don't want back pressure behind anything.
You want exhaust velocity. :P

Re: Went to the dyno today and it sucked. Help please.
 

backpressure can be a good thing on a turbo street car.

just like small charge pipes can be good too.

Re: Went to the dyno today and it sucked. Help please.
 

Dammit! Well we replaced the plug wires, and the rotor (it was rusted). We fixed the dip and i'ts making more power with the timing fixed. It has some random misfiring like once in the pull. But it still isn't making the power it should. I'm out of ideas. And so is Matt.

Re: Went to the dyno today and it sucked. Help please.
 

basic rule of turbocharging - the less backpressure the better
learn yo ---- fool

Re: Went to the dyno today and it sucked. Help please.
 

check compression.
check CAM timiing,

Re: Went to the dyno today and it sucked. Help please.
 

I think the compression is fine, it's runs great when not in boost.


This is how Matt explains it

Alright we did some more tuning today and it still isn't making a difference. In fact bigwig found out how to import the p13 maps into uberdata so this time we were using actual p13 timing maps. Total timing is around 22*. We got the afr line real smooth right up around 11.7-12:1 with no dips. We even regapped the plugs(when i checked them they were at .035) down to .028. We also replaced the plug wires with ngk blues and replaced the rotar in the distributor. It is very apparent that the car is having ignition problems. There are all kinds of little misfires in the graph where it goes reads very lean for a split second that show up on some pulls and on other pulls they don't show up except for maybe 1 or 2 little misfires. I even tried adding and subtracting timing in the boost columns without much change at all. There is definintly something wrong here

Re: Went to the dyno today and it sucked. Help please.
 

Well I think I'm going to be replacing the wastegate beacuse it's an ssautochrome and it is now running 11 psi, and it should be around 8.5 psi. And I may replace the turbo also because it's also from an ssauto kit, and even though it says 10 psi, maybe it's crappy 10 psi. I dunno. I wanna get a bigger turbo anyways.