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I had the choice, I rebuilt my engine and chose not to port the head, or oversize the valves. I could have also gone with VQ35 cams but I would rather max the stock setup as I knew the turbo would be my limiting factor anyway.

Do you think the engine is more efficient now?

That was your choice and I respect that...

I personally would rather build a setup around the motor, not a motor around a stock set up...

Do I think the motor is more efficient now? No...

Am I positive it is more efficient now? Yes!

Then why was 8 degrees of timing required to be removed to stop the det? Why was the motor making less powerz at the same boost? Something aint kosher...

Did you double check the cam timing?

Less power?

I believe peak power figures were same, and what is power anyway?

Torque x rpm?

Why did the new motor create 30 more Newton meters of torque??

Cam timing is not the issue!

If you cant get those exhaust gases out quick enough, it is eventually going to reverse flow back to the valve, those gases carry extensive heat, especially in the first stage of the burn process... more then enough heat to act as an ignition sorce for the fresh air/fuel trying to make its way into the bore...

Then why was 8 degrees of timing required to be removed to stop the det? Why was the motor making less powerz at the same boost? Something aint kosher...

Did you double check the cam timing?

This. Unless there's something you've missed telling us, Scotty's got a point.

A bigger rear will only exacerbate the lag issue though. I'm not trying to shit on the engine build, quite the opposite, but I have completely different ideas on extracting usable power and torque from engines. I guess you are trying to get around the one limitation you refuse to discuss, fuel quality...

Civic is a pos

Didn't even start his morning lol

I get what your saying that I'm a crap driver. Ain't no dispute in that :P

But I thought whilst the head is off I may as well do it. *insert doitphaggot.gif* so in the future I wouldn't have to do it again if I decided to chase a crap load of power for the lolz. Know what I mean jelly bean?

you're not a crap driver, they're just really good ones.....:rofl:

yeah i know exactly what you mean,Im trying to decide if i should pull the head off my toyota for the same reason.....if I leave it on my car will remain slow but my wallet will remain thick...if it comes off my car will get faster but my wallet will get thinner...its a balancing act..

But I already said I didn't want to go E85 :/

I'm sure pump 98 fuel is not the limiting factor at the moment, plenty of people are making more power on 98 Octane

A bigger rear will only exacerbate the lag issue though. I'm not trying to shit on the engine build, quite the opposite, but I have completely different ideas on extracting usable power and torque from engines. I guess you are trying to get around the one limitation you refuse to discuss, fuel quality...

im not sure it will exacerbate (< i had to google this word ) the issue...would allow more free flowing exhaust...which might be all it needs...with the gases flowing so fast its going to spool up damn fast anyway it just needs to be able to vent it...I'd be looking at a highflowing billet comp wheel of some description though and EG a big one

Yeah I think we need to all remember here,

Trent was the guy tuning the car and will all the data and came to the conclusion that the turbo is a limiting factor

Plotting the engine on a GT3076 compressor map also confirms this

In saying that I will be trying to book in a dyno run sometime soon to run it without the cat back exhaust, airbox/panel filter, check the cooler system to see if there is somesort of restriction elsewhere

I'm sure once I stick a bigger turbo we will get results and then we can have a tea party and all eat scones and butterscotch finger biscuits

I get and respect that scotty, dont think im trying to put you down or get you upset!

I do believe a larger housing will have a minor effect of the lag, but I wouldn't class it as a lag "issue"

Its a circuit car, get it to boost and keep it there!

Are you saying fuel quality could be an issue? :/

Can I have scones too?

Tony gtx3076. External gate, 3.5" exhaust, cut a nice hole in the airbox.

Trust me, it'll be fun.

If you aren't making 320+kw buy a new car you rich accountant

f**k you Vic guys :( I wanna come to the tea party too, damn it.

Pick me up on the way past!

I'll bring the whipped cream

Us Vic guys even bring out the Cadbury favorites at these functions

Can I have scones too?

Tony gtx3076. External gate, 3.5" exhaust, cut a nice hole in the airbox.

Trust me, it'll be fun.

If you aren't making 320+kw buy a new car you rich accountant

I'll do this when you get rid of the Merc and get back into Jap cars :P

I think this is the bit of when people don't understand. By looking at a compressor map it only shown the capability of half a turbocharger, the exhaust side is not known. In this turbo system the maximum capacity of the turbocharger is reached when one out of the two ends reaches its capacity.

We can have a selection of turbine wheels and housings to run in combination with a single compressor wheel depending on the application and ends up with a variety of results. This is also the reason that I prefer hand on experience, as the end dyno reading is an more accurate prediction.

By looking at this result it sown that the compressor efficiency is not reached, how ever the turbine side is. By installing a larger compressor wheel based on the compressor map will only make the matter worse. matter fact of been a -12 degrees timing instead of the -8.

If external gate and E85 is not an option, then it will need a much larger exhaust wheel or housing, compressor end doesn't necessarily needs to be replaced. How ever by doing so it would affect response in a noticeable degree. Since the car still use factory drain trans, for road use and city driving, it won't be too comfortable.

Whilst I agree with you Stao, if you make the assumption that the turbo is well matched (and you'd be the one to tell us how well matched the front and rear of this particular turbo is, given that we're talking about an SS2, not a 3076 here), then if you plot your operating point off the top end of the compressor map then you'd have to think that you were also pushing the turbine side too hard.

The real question here is whether that operating point on the 3076 map is equally as bad on the SS2 compressor.. Actually, it's not. I still agree with you. The real question is whether the SS2's turbine side is too small, but I thought I'd point out that we're looking at an orange map when we're talking about an apple compressor.

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