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Discussion Starter #1
Hi list, here is the situation I got a 92 classic with a bluebird det.I took it to the dyno three times in the past 6 months this is what happened.
11/11/00 Dyno run
max hp 260 @ 6700rpm, max torque 237 @ 5300 rpm.
Set up: DET, stock maf, 370cc,bosch 1:1 fpr, tt pump,fmic,TO3 with super 60 compressor.48 a/r turbine housing @ 11 psi, 2.25 down pipe(8 inches long then converts to 2.5),2.5 crushed bend exhaust no cat,custom tubular manifold,ACT pp with dual friction disc,ngk r5671a-9 gapped @.032,stock plug wires,msd 6a.Timing @15,93 pump gas.

02/8/01 Dyno run
Max hp 232 @ 6400rpm, max torque 230 @ 5250 rpm.
Exact same set up.Had to advance timing(17) to get 230hp,I was getting 225.Used the pfr7b-11 stock gap no improvement.

06/26/01 Dyno run
Max hp 248.6 @5900rpm, max torque 264 @ 4650 rpm
Same set up but with act clucth with 6 puck sprung cooper disc, msd 50lb,cobra maf,4 bar fuel program @18 psi(the car would go up to 22 psi then back down to 18)
I had to lower fuel pressure to get more hp the car was running too rich.
I did one run @ 9 psi and only got 175hp.(this was the first run of the day)
On the last two pulls the car started blowing oil and gases through the dip stick hole and there was like 10 ounces of oil on the oil catch can that I just put in the car, this happened when the car reached 20 psi.

After that I did a compression check and all cylinders were @ 155 I put some oil in and they all went up by 7 or 10.
Now the questions
-What could be the cause for the hp loss(the turbo is in good shape not burning of oil or too much play in the shaft)?
-If compression is getting into the engine why the compression test did'nt reveal it?
-Why did I have to lower the fuel pressure to get the car running better, right know I'm feeling like I wasted the xtra money on the 4 bar program?
Opinions will be really appreciated.
TIA,sorry for the long post
Hector Firpo
 

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Living up Boost
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893 Posts
Let me start off by saying that I don't know much about turboing the car. But I thought that the stock MAF should not be pushed passed 8 psi...could be wrong, or maybe it was 10? You think you were running lean in the beginning?

-saaby
 

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Discussion Starter #3
No when I was running the stock maf the plugs looked ok. I think it was getting close to the limit but the engine did not detonate.
HF
 

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G-unit
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1,132 Posts
Looks to me like you car isn't running good up top, Max power went from 6700 to 6400 to 5900? Torque is also dropping. Is that 2.5 exhaust enough? Kinda seems to me that you have some backpressure issues.
 

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Not on fire... yet
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591 Posts
I would close the plug gap down to about.025-.020 and go to a 3" exhaust diameter. How is your PCV system routed??

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93 NX2K
some stuff and a DET
"project street mod?"
1988 BMW M3 w/ a few toys
 

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Discussion Starter #6
The ventilation on my valve cover is conected to the one coming out of the block then to the oil catch can.
And about the back pressure I got a 3inch "y" in place of my cat, wich I opened for the second dyno day and it made no difference. But know my main concern is the oil and gases coming out of the dipstick hole when I hit 18 psi. I did the compression check and allcylinders were @155.
HF
 

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El Chingon
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892 Posts
What do you mean "the ventilation on my valve cover is conected to the one coming out of the block then to the oil catch can"? Off of the valve cover (on the driver side part of the engine) one of the outlets should go into the top of the stock catch can and the botton of the catch can should go back into the block. The other outlet on the valve cover should go into either an aftermarket catch can with a breather or back into the intake tract pre-turbo (between the MAF and the turbo inlet). I would go with the aftermarket can simply to keep the oil vapors out of the intake tract, but that's up to you. Is this how you have it?

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David
'98 Super Black SE w/stuff
 

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El Chingon
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892 Posts
So you completely removed the stock catch can? Hmm, I've never done that before so I don't know what negative effects that could have, but every turbo SE-R I've dealt with so far has had the stock catch can in place. Here, take a look at a good pic of Jay's car. This is how I was telling you to do it in my previous post.



I also think you should close your spark plug gap down. .020 - .025 just like RacerX reccomended.

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David
'98 Super Black SE w/stuff
 

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former pulsar car whore
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1,397 Posts
Hmm, isn't 18psi a lot of boost to be running on a T-25 turbo? That could be why you aren't making as much power up top, if you are turning up the boost too much with the small turbo.

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97 Super Black 200sx SE-R
Hotshot CAI, custom 2.5" catback with dynomax super turbo muffler, Hotshot header, UR pulleys (2 set), JWT ECU
 

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This is kinda weird, but can happen...It seems like first off that you may be boosting ineffiecent. Cause 18psi on the stock T-25 is too much. I think if you knock back to maybe 12 or so it would be faster. I dunno if you relize that, but the turbo is spooling way up, making it all heat up, etc...And i think the 3" would be a great investment.

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Enjoy the ride...
 

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Discussion Starter #13
Guys is not a t25 it is a modified chrysler TO3 with a .48 a/r turbine housing and a super 60 compressor wheel. The thing is that on the first run in my last dyno day I ran 9psi And just did 170hp and the car was running super rich with the 4 bar fuel program.
HF
 

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El Chingon
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892 Posts
So is it running any better? Did the shop you were dynoing at have any type of exhaust gas analyzer? If so, did it indicate your car was running rich? Maybe you should turn the fuel pressure down a bit. I think Jay had to do the same in order to get the car running right.

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David
'98 Super Black SE w/stuff
 

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El Chingon
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892 Posts
What is your base fuel pressure at? What did yo lower it to when you got the 248 hp?

David
 

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Not on fire... yet
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I couldn't tell for certain, but is the vaccum line entering the VC (intake cam side) going to the pipe before the TB??....
If it is then you have boost going into the valve cover and then into the crankcase...which is what keeps pushing the dipstick out...and the oil.

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93 NX2K
some stuff and a DET
"project street mod?"
1988 BMW M3 w/ a few toys
 

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Discussion Starter #18
I had to turn down the fuel pressure to get the 248 hp . The owner of the shop where I dynoed the car was the one that sugested that the car was running rich because the hp line was very erratic(many ups and downs)I trust the guy's judgement ,he is the owner of the sakura.
HF
 

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En mi barrio..
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I'm getting off topic alittle bit........

<font face="Verdana, Arial" size="2">Originally posted by Hector Firpo:
.....I trust the guy's judgement ,he is the owner of the sakura.
HF
</font>
Hey, where is the Sakura! This weekend we had to cars run faster than his 7.54. The Siguel Racing RX-7 ran a 7.48 and a yellow Ford Focus with a SHO V6 ran a [email protected]!!

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Aint nobody dope as me, i'm just so fresh and clean
paradiseracing.homestead.com/home.html
 

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El Chingon
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892 Posts
No, there's two lines off the VC; one to the aftermarket catch can and the other straight into the return in the block. Here, check it out:



But, the routing could still be the problem.

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David
'98 Super Black SE w/stuff
 
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