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Discussion Starter #1
today i dyno'd for the first time. im not sure exactly how i feel about the results. i dont have a host for the pics (hint hint) but ill give you a good story.

first, it was done at SlowBoy Racing in Indiana, PA, on a dynapack.

first run, i learned exactly how wrong my boost gauge really is. my boost gauge read 16ish psi. the dyno says 13.5. (which means that at the track i was actually only running 12.5ish psi. :smile: ). i peaked tq at 198.3 ft/lb at 5278 rpm and 200.4 whp at 5346 rpm. :cry:

I wasnt happy at all w/ that run. i figured i need to dial in a bit more boost. so i blindly turn the little knob a bit.

second run, i hit 228 ft/lb @ 3607 (much better) and 218.2 whp @ 5288 rpm.
the only thing is, just as boost reached 16 psi (peak) my tq numbers dove from 228 to 210 by 4200 rpm and then worked it way up to about 225 before falling off. any ideas? my best guess is that my na f.p. cant keep up very well w/ 16 psi the ecu pulled timing. the dyno guy told me that i probably would've seen at least 240-245ft/lb had that spike not happened.

thanks for listening. please comment,
jon
 

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Is your boost gauge and the dynos boost gauge tapped into the same location?
Where are they tapped into?
Your 1/4 mile indicates a lot more than 12.5 psi. Something does not sound right there.

As for the fall off, 4200 is right around where the TVIS should be opening up the extra intake valves. You are on the CT20B right? Either way your torque will fall off in the higher rpms.
 

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Discussion Starter #4
yes the dyno had a "T" so i just "T'd" into the hose leading to my boost gauge. idk whats up w/ that. maybe its inconsistently inconsistent?

i understand that my tq will fall in the high rpms. but ...... i am curious as to why it would drop 18 ft/lb over 600 rpm and then climb up another 15 ft/lb over the next 400 rpm. that much doesnt make sense to me.

and danny ... i'll have pics up as soon as i find a host.......lol

*EDIT* - its a ceramic ct26
 

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I am guessing that you started to lose torque until the TVIS opened up the other 4 valves and you started building power again.
 

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As Jeff said something is not right here, your 1/4 miles indicates more than 218whp, not to mention that I'm very positive you ran more than 13PSI. I dynoed 266whp with my CT-26 @17 PSI but I had more mods than you. Also my best 1/4 mile (with ct-26) is very similar to yours, I'm sure if you car pulled timing you ran more than 13PSI, but yet the dyno seems low to me. note: I found that if you run the "T" for the boost gauge from the TB hoses it won't give you an accurate reading, is your boost gauge hose connected to the back of the manifold?
 

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Discussion Starter #7
it is connected near the throttle body. the drastic drop happened on the second run when i did run 16 psi.
 

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Discussion Starter #8
think it would be a better judging stick to use mods vs. whp?

2.5" ko dp, 3" ko exhaust, apexi intake, mbc, clutch, motor mounts.
 

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Jon, your boost gauge should be tapped into the intake manifold. I would T it into the OEM Map sensor or use one of the unsed locations on the back of the mani. Just look for the littel rubber hose "Caps".
 

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sxytrtrcr said:
it is connected near the throttle body. the drastic drop happened on the second run when i did run 16 psi.
That's your problem, the boost gauge is not reading accurate because of this, listen to jeff and tapped the gauge into the intake manifold.
 

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Discussion Starter #14
where? maybe a pic of your setup? i looked today and it didnt look like there is any easy place to tap for boost other than where it is.

so i may not have been at 16 psi at the dyno?
 

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sxytrtrcr said:
where? maybe a pic of your setup? i looked today and it didnt look like there is any easy place to tap for boost other than where it is.

so i may not have been at 16 psi at the dyno?
I'll post PICS tomorrow, is cold out and dark.
 

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Ok stand behind you car and put your hands on the Intake Manifold. Now you look to your left of the manifold attached to the trunk part right next to the manifold there is this black lil box with 2 hoses goin in and out. Trace that one to the manifold it will be in between the manifold and the trunk. Now that you found that run your hands or just look down to the right side of that. There will be a lil black hose but its capped off from stock. umm hope that helps its not that hard to find just look down.... umm haha there was a joke hidden in there....yawn...
 

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Discussion Starter #18
sxytrtrcr said:
so i may not have been at 16 psi at the dyno?
also, i relocated my boost gauge source and it still reads the same. also, i think it was a fine source where it was b/c i recall him telling me that the computer read 19 vacuum at idle and my boost gauge usually reads 15-16.

however, do you think that very large dip in torque can be at least mostly cleared up w/ a fuel pump?
 

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sxytrtrcr said:
also, i relocated my boost gauge source and it still reads the same. also, i think it was a fine source where it was b/c i recall him telling me that the computer read 19 vacuum at idle and my boost gauge usually reads 15-16.

however, do you think that very large dip in torque can be at least mostly cleared up w/ a fuel pump?
what pump do you have? if you have the NA pump DO NOT run you car hard until you get an mr2 turbo or supra TT pump.
 

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Discussion Starter #20
i've ran my car plenty hard since the swap w/ just the na pump without a problem. i have a walbro 255. as soon as i get a [email protected] check from the va im gonna have it installed.

regardless of that, do you some of the "problem" could be solved w/ just a pump?
 
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