Guess my H.P

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Hi all
Getting really close to having things sorted well enough to put the car on the dyno, Just sorting out a small cooling prob and a slight exhaust leak then will be taking to the dyno for a tune
Who wants to take a guess on RWHP figures .....Guesses on the 1/4 mile as thats where it will be going once its off the dyno
Its a rebuilt 2V 250 with a mild cam dont know what specs The Carb is 350 holley the valve train is standard,,, Not sure of compression ratio (wait and see if its too high) It has an EFI fuel pump and Malpassi regulator the Turbo is a Garrett TO4B .94 A/r P trim it has a 650 x300x75 intercooler and a basic MSD unit on a dizzy that has been mechanically fixed to not advance beyond about 27 deg Its backed with a 5 speed manual and a 3.5ish diff ratio
Shes a bit heavier than an XP or a mustang I would hazard a guess at 1600 kg
Any Guesses????
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I'm guessing on about 150-160 RWHP in current trim. There's probably more but I reckon air deliver will be the sticking point in early trials.

Cheers, Adam.
 
Well seeing how your setup is almost exactly the same as our's, I'd say you could see in the neighborhood of 300hp at the tires. That assumes that you're going to run it around 18lbs. of boost.
I'd also recommend you change the turbine housing to a smaller one. Say .69 or even .58 A/R. That .94 is going to take a bit to spool.
Later,
Will
 
Does10s":3iaknno3 said:
Well seeing how your setup is almost exactly the same as our's, I'd say you could see in the neighborhood of 300hp at the tires. That assumes that you're going to run it around 18lbs. of boost.
I'd also recommend you change the turbine housing to a smaller one. Say .69 or even .58 A/R. That .94 is going to take a bit to spool.
Later,
Will

I'm surprised Will, I thought you'd be much higher than that. Not to insinutate that your 1/4 times are lacking.
 
What compressor trim are you using?

I won't even BEGIN to start guessing until I know what compressor is on that turbo.
 
XA 250":3hp21lmh said:
a basic MSD unit on a dizzy that has been mechanically fixed to not advance beyond about 27 deg

No rev limiter function? That might be bad....If a u joint breaks under boost and full throttle, that engine is done.

If you have a fair amount of dyno time scheduled, retard the timing about 6 or 7 degrees, then bring it up on subsequent runs so you don't get detonation right away....actually, what fuel will you be using? (and what octane method?)

That makes ANOTHER huge difference before I even begin to start guessing.
 
i reckon about 215-220hp.
i like your setup xa 250. have you any more pics of it mate.
can you take your intake manifold off with out removing the wastegate?
 
also, how much boost will you attempt to run?

20 psi will get you 300 HP for SURE!
 
I put a 74 jet in or are you talking about the float If you are I have replaced it with a new one in the carb kit but its standard
 
XA 250":1uezjcia said:
I think the trim number on on the comp side is .56 I purchased the turbo recond from a Turbo specialist shop nearby

That sounds like a weird number...ask them for me what it is. (or pull the cover off and measure the smallest and largest diameters of the compressor wheel and I'll tell you)

If it is a T5/6 trim it will be a shade on the smallish side for a 250 but will get you to the 300 mark easily enough. I agree with Will...the .96 A/R on the turbine housing is a bit large. .68 A/R will help spool a lot sooner on the street.
 
Oh yeah.....you still need to "T" into your brake booster vacuum line and run a hose to the nipple on the top of your blow-off valve.
 
......and run a pressure line to you wastegate!

What size inlet needle and seat are in your carb?? If you have less than .110" you may run lean. A .120" needle and seat may be needed.
 
There is a pressure line to the waste gate and a acuum to the bov just disconnected in the pic. As for the .96 ar I wanted to (on advice from yourself and Will )go to a smaller a/r but the turbo guy talked me out of it
When you look at the Aussie websites and what they use on there4.0 EFi xflows the tend to be .90 to 1.1 where as the non xflow head on this site tends to be .50 to .70
In the end he did me a good deal and said he would change it over if it proved to be to large(I did spend a while arguing your case)
I picked a my radiator new 3 row today so that should fix the cooling hopefully and will soldier on and see how it turns out
I took the exhaust manifold off as there was a small chuff chuff chuff that i needed to fix and it turned out to be quite a large leak on the manifold to turbo flange(As I just learnt to weld) but have fixed this today
When i had it running for the few short trips I only reached 5-8 psi although the wastegate was set at 10 ,Not quite sure why but hope the exhaust leak was something to to with this and not the .96 p trim
It making this boost at 2500-2750 rpm untuned so hopefully once leaned out and advanced alittle this may improve slightly
Ill wait and see how it goes.... :D
 
XA 250":1wfzksmx said:
I only reached 5-8 psi although the wastegate was set at 10 ,Not quite sure why

Out of curiousity, where does the line for the boost gauge tap into?
 
Its in the rear of the inlet manifold, Im having problems with the gauge jumping around I think I may run it on the other side of the butterfly and see if this makes a difference I know it wont show vacuum but wnt to see if its the gauge or pulsing I dont think you can see it in the pic but there is a couple of tee,s underneath the BOV
 
No dyno results yet stil having trouble making more than 5-8 psi Im going to remove the pressure side pipe off the turbo seal it up and pressurize the intercooler and carb to see if im losing boost there if im not at least it crosses one thing of the list. I have a lot of work on at the moment so cant see it getting to the dyno for at least a month.
Its still great, the amount of torque increase is huge (as judged by the wheelspin) cant wait till its well set up
 
Great work with the car, I can't wait to see it running! Especially down the quarter mile :lol: On a sidenote, do you know what the name of the colour of your car is?
 
Its called Hothouse green Its a Holden(GM) color from their 2002 2004 ranges....I also cant wait to get down the 1/4
 
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