.84 Hotside, How Much Boost?

[DR SCHNITZEL]

I was wondering what amount of boost i can safely run on my t04r with a small hotside of .84. I am running 1.2 bar and i know the hotside is quite restrictive and after one drag run the manifold glows for about 1 minute. The spool is incredibly good 1500 rpm ish.
 
Would a larger hotside be more efficient on my standard ports. it is a fast street car .
 
What boost is safe. I dont want to melt my turbo kit or my engine

[BlitzBoy]

There are people in the US run this turbo up to 1.5 BAR on race gas.
If you go past 1.2 BAR you get to the limits of our pump fuel and more inclined to det, so either run WI.

I wouldnt change your hotside on stock ports, you wont gain by going bigger hotside at the same boost level, you will probably lose bottom end power

[DR SCHNITZEL]

Nice one blitz. Is it worth me getting a 3 bar map sensor if im runnng 1.2 even though the stock only reads 1.15 ish. I have quite a bit more fuel than needed in those cells for safety.
 
Also when you said i could advance the timing some on my map as im stock ported not street as you were. how many degrees are we talking? so far my knock hasnt gone over 60.
 
I think ill keep to 1.2 for now. I just need some kind of ignition amp now and im pretty much done and dusted. Still running the standard clutch with no probs whatsoever.
 
Cheers blitz U da man

[m1tch]

You will need a 3 bar map sensor as you are already using 3 bars of pressure lol:

-1bar vacuum
0-> 2bar boost
= 3 bar

[m1tch]

Also, that T04Z is smaller than the OEM FC turbo? the OEM FC turbo has a hot side of just over 1 lol

[L18M]

just wondering with that size hotside... would it run out of puff towards the end of the rev range?

[BlitzBoy]

Also, that T04Z is smaller than the OEM FC turbo? the OEM FC turbo has a hot side of just over 1 lol

what have u been smokin dude!? lol :guinness

you are getting confused, AR is ratio to the turbine size wheel

Physically the hotside of to4r is bigger then the oem fc turbo.

In regards too timing I would leave it as is, you only gain a little by going an extra 2 degrees but you will increase the risk of det

The max on the stock map sensor is approx 1.3 bar

[DR SCHNITZEL]

So i wont need a 3 bar map sensor? My pfc hand controller only registers up to 1.15 this is why i asked. I realise i am in the 3rd bar (absolute)
 
The .84 hotside seems to spool super fast and it does hold well and create good power to 8000 rpm. I am not sure if a slightly bigger hotside would be better. id sacrifice some low rpm spool to get a later or longer peak power curve. Im going to have to get this on the rollers.
 
Didnt you have the same tub as me and saw 450hp at the same pressure?
 
Also Blitz the map has 10c split in >0 boost. What kind of gains and risks would i see if i reduced these to say 8 or 6. More knock? I havnt touched anything in this area yet

[BlitzBoy]

You only need the bigger map sensor if you going to be running monster boost pressure and you going drag racing, I think 1.2 BAR on your setup for fast road is more then enough lol.

I had a T04Z that produced 450 rear wheel horsepower on a street port at 1.3, before that I had a T04R produced approx 410 rear wheels on a street port at 1.2

Leave the split as is in the boost areas you wont gain anything, tried different combos over the years and 10 split in the boost areas works best, you want a good efficiant burn a too narrow split wont give you this and might leave you with unburnt fuel = less power

[DR SCHNITZEL]

Cool so 410 at the wheels * 1.15 (tranny loss) about 471.5hp at the flyish. Good for going to get the sunday paper.
 
My new engine doesnt idle smoothly (still) and never has. The tuner couldnt eradicate the prob and now single its still stumbles at idle. (what about the split in this area (currently 8 degrees)
 
The only other area id like to adjust is the idle and the 1000 to 2000 rpm. I have lots of extra accell injector to try to stop the stumble at low rpm. with limited success and my afrs are 14 dead in this area

[BlitzBoy]

Yes but you have to know those figures are for a Street Ported engine, you are on stock ports so take away a good 50 -70 rwhp off my figure.

Split wont effect your idle too much change that to ten and give it a try.
Also on idle try putting some fuel in to stop the stumble, try 12.5 to 13 afr might help

[DR SCHNITZEL]

Ill get this on the rollers and see what the port would gain me. a .84 hotside must be ok on standard ports of its not running out of puff on a street ported motor? So my setup must be quite efficient, its certainly good to drive

[BlitzBoy]

when you get it on the rollers for your power run make sure the dyno operator does not play around with your boost controller unless they are a rotary tuner, u dont want an operator blow your engine up if they wack up the boost

[DR SCHNITZEL]

ILL make sure they do it at 1.2 bar max. I did not realise you would make so much extra power with a mild street port.

Going to mess with the idle tomorrow night, try to get it smoover.

I do need to get twinspark or msd on the leading that boost tends to blow the spark out periodically and im not getting consistant power. Maybe 10s in the leading would help.