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Sloppy Jalopy
2,438 Posts
Were you wanting to make more power?

What kind of dyno was used? Hub or roller type?

Your power level isn't too wild honestly, all things considered with your build specs.

Comparing your build and turbo specs, your turbo moves a less CFM at the same boost pressure than mine does, but not that much less. Also since you're not long rod, you're likely 8:1 or below, mine is around 8.5:1 static comp.

Keeping this in mind, use my build for comparisons sake.

My grey car has 2.5" full exhaust (sidepipe) with resonator, a GT32 journal bearing turbo, crappy cast mani with gate on #1 runner, but it has a good cam and port matched everything in the head.

On 15psi, it made 310 whp with a very reputable D series tuner dialing in timing as it should be for a D series on pump gas.

Since you have a cam, staggered runner top mount manifold for properly timed pulses, central mounted WG with a 3" bumper dumper, you move air out much more efficiently than I do.

If your tuner has timing set more agressive (most tuners not familiar with D series will), i could easily see you making what you're making at 16psi at your estimated CFM at 7000ish rpm.

Its not too unexpected.
maybe the garrett is just that much better of a design than the maxpleeding turbs.?

Sloppy Jalopy
2,438 Posts
Dude, I'm so sorry I must have been smoking crack...

I literally thought your thread title said 335whp at 16psi!

Forget everything I've said so far lmao.

Ok, coming down off my crackpipe, again I apologize, lets re-discuss things.

235whp at 16psi, on your turbo, with your manifold and downpipe size. Yeah, something else is going on. With my stock Y8 cam on Engine V1 (vitaras with long rod, about 8.8:1, no port matching, same crappy exhaust mani), I made 250-260ish whp at about 15psi with my same turbo, so I'd expect you to be around the same at 16psi with your turbo.

And your tuner said adding timing and boost didn't make the engine respond then huh? As @Soul Engineering said, definitely check for boost leaks and other manifold leaks.

  • What is your mechanical cam timing set to? Stock? What about base ignition timing?
  • What do your cold and warm compression readings say?
  • What is valve lash set to cold?
  • Is VTEC engaging, and engine feels like it runs smoothly when it engages?
  • No pushing coolant or similar under boost?
  • Could wastegate be stuck open, or unable to vent the top chamber effectively? What frequency/duty cycle is being used to control the wastegate with the MAC solenoid?
  • Your camshaft, do you know how much baked in overlap it has in VTEC?
    • I tried finding specs for it, it doesn't say the 105300 is a turbo specific camshaft. Do you have cam card for it? Pics?
    • Curious if its an N/A specific grind. If it is, it will have a lot of overlap in VTEC, so in boost, you'll be blowing all your charge air out the tail pipe! Need to verify overlap based on cam card info.
Off the top of my head, these are the things that come to mind to check.

I hope the dyno operator set the dyno up correctly as well lol... just one other thing to be aware of! If they got the setup wrong, then it will be calculating whp incorrectly. But by the way you describe this guy, he's used it a bunch and that shouldn't be an issue...

stick to the ganga man.

that cam should work ok with boost .
but only seen them when used with a longtube header..

I'm curious if the disable code 9 could have caused other issues .

Does it sound and feel like it runs strong?or is it sluggish and lazy?

I mean what's a number...?

Sloppy Jalopy
2,438 Posts
Cam timing is 1* advanced and Ill have to check the base timing another day since it was set by the tuner after they played with cam timing.
Gonna do a compression test soon and I've read that around 150psi is good for low comp vitaras
Setting valve lash was a little weird and I did it twice to make sure and If I remember correctly I aimed for .007 intake and .009 exhaust. I'll double check it as well when I get the chance.
VTEC engages and runs strong.
No coolant pushing or anything after multiple rips.
Wastegate works fine and where it vents all the runners have just become one big "collector" It's and SPA Turbo Top mount if you want to get a better idea of how it looks inside. Duty cycle is set to 75% and frequency is at 33
I wanted to get the BC Stage 2 Forced Iduction Cam but, they were out of supply and I would've had to wait months at the time. I've seen people recommend this cam on the forums before so I just went with it.

Cam Specs from comp cams site:
Advertised Intake Duration:260
Advertised Exhaust Duration:268
Intake Duration at .050 Inch Lift:220
Exhaust Duration at .050 Inch Lift:216
Intake Valve Lift:0.455
Exhaust Valve Lift:0.43
Lobe Lift Intake:0
Lobe Lift Exhaust:0
Intake Centerline:111
Exhaust Close ATDC:0
Intake Open BTDC:0
Exhaust Open BBDC:0
Intake Close ABDC:0
not the problem but
I would go a little looser on the valve lash .just me.

spit ball ,Y8 VMS Variable Cam Gear ?are you positive it's the one for a y8?
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