so you changed the wastegate springs and raised the boost controller?
are the rods and vitaras low compression?
are the rods and vitaras low compression?
16psi of Boost Only Making 235whp? Need Help!!
The build is as follows:
Bottom End
Head
Turbo Setup
Fuel
Misc
As soon as the car got on the dyno it threw a code 9 (No. 1 cylinder position (CYP sensor). Tuner said it was a common problem with running OBD2 Distributors on OBD1 ecu's but, the car hasn't thrown the code in months of daily driving the car. He bypassed the code and the car ran fine with no misses. Once he got to doing power pulls he said the car wasn't responding to more boost/timing and that something was holding the car up. Seemed like it could be cam timing so they double-checked and everything seemed good. Adjusting the cam gear only made less power. After a while of trying to figure it out, we had nothing and came to the conclusion that the setup just wasn't efficient and just won't make the power. Even then they thought it should make more than that at that boost level but, said that the manifold is choking it up and the china turbo just isn't efficient enough.
From my understanding, these setups are making closer to 300whp at that boost level. I was wondering if anyone had some insight on what might be causing this issue.
The dyno is a 4-hour drive so I want to make sure I actually fix the issue before I waste a whole weekend going back.
Pictures of the setup as it was at the dyno and dyno sheet:
![Car Vehicle Grille Hood Light]()
![Vehicle Motor vehicle Automotive design Automotive air manifold Hood]()
![Rectangle Slope Plot Line Font]()
Bottom End
- Stock Y7 block no guard or anything
- 75mm Vitara Pistons
- Scat H-beam Rods
- ACL Race Bearings All-Around
- OEM Y7 Oil pump Ported and Shimmed
- D16Z6 Crankshaft
Head
- Refreshed Y8 Head
- BC Springs and Retainers
- Comp Cams 105300 Cam
- Y8 VMS Variable Cam Gear
- ARP Head studs
- Nippon Racing MLS Headgasket
Turbo Setup
- MaxSpeedingRods "GT3076R"
- SPA Turbo Cast Top Mount Manifold
- CX Racing Intercooler Kit
- Treadstone TR11 Intercooler
- Turbo Smart 38mm Wastegate
- MAC 3 Port Boost Solenoid
- 3" Downpipe Out the passenger Bumper with wastegate tied in
Fuel
- Walboro 255lph pump
- K&N Fuel Filter
- AEM on Rail Fuel Pressure Regulator
- Fuel Injector Clinic 775cc Injector
- Shell 93 Octane
Misc
- BKR7E plugs Gapped to .022
- Stock Old Distributor and Plug Wires
- Rotella T6 15w-40 and K&N Filter
- P28 ECU With s300 v3
As soon as the car got on the dyno it threw a code 9 (No. 1 cylinder position (CYP sensor). Tuner said it was a common problem with running OBD2 Distributors on OBD1 ecu's but, the car hasn't thrown the code in months of daily driving the car. He bypassed the code and the car ran fine with no misses. Once he got to doing power pulls he said the car wasn't responding to more boost/timing and that something was holding the car up. Seemed like it could be cam timing so they double-checked and everything seemed good. Adjusting the cam gear only made less power. After a while of trying to figure it out, we had nothing and came to the conclusion that the setup just wasn't efficient and just won't make the power. Even then they thought it should make more than that at that boost level but, said that the manifold is choking it up and the china turbo just isn't efficient enough.
From my understanding, these setups are making closer to 300whp at that boost level. I was wondering if anyone had some insight on what might be causing this issue.
The dyno is a 4-hour drive so I want to make sure I actually fix the issue before I waste a whole weekend going back.
Pictures of the setup as it was at the dyno and dyno sheet:
1 - 20 of 39 Posts
Yea the boost controller was set to make 16psi and it did. Yea they aren't long rods so with the vitaras it should be pretty low compression.so you changed the wastegate springs and raised the boost controller?
are the rods and vitaras low compression?
Boost leaks? That's generally the cause. What fuel pressure regulator and does fuel pressure rise as boost comes in?
I'd bet it's either boost leaks or ignition break up. I'm wondering how the tuner got past the code? Probably just disabled it, which isn't really helping. Convert the dizzy to OBD1 or go coil on plug and I'd bet the issue goes away.
I'd bet it's either boost leaks or ignition break up. I'm wondering how the tuner got past the code? Probably just disabled it, which isn't really helping. Convert the dizzy to OBD1 or go coil on plug and I'd bet the issue goes away.
I would think boost leak but since the map is in the manifold and is seeing 16psi then it could only really be leaking at the injectors or IM gasket. I'll do a boost leak check soon anyway. I asked the tuner about the dizzy situation and he said that it wouldn't be affecting power since it's not breaking up or missing. I've read of a guy having a similar issue and replacing the dizzy fixed it so ill look into an OBD1 conversion.Boost leaks? That's generally the cause. What fuel pressure regulator and does fuel pressure rise as boost comes in?
I'd bet it's either boost leaks or ignition break up. I'm wondering how the tuner got past the code? Probably just disabled it, which isn't really helping. Convert the dizzy to OBD1 or go coil on plug and I'd bet the issue goes away.
Fuel pressure is good and its an AEM Pressure regulator. AFR's are perfect throughout pulls.I would think boost leak but since the map is in the manifold and is seeing 16psi then it could only really be leaking at the injectors or IM gasket. I'll do a boost leak check soon anyway. I asked the tuner about the dizzy situation and he said that it wouldn't be affecting power since it's not breaking up or missing. I've read of a guy having a similar issue and replacing the dizzy fixed it so ill look into an OBD1 conversion.
I'm using an obd2 distributor on my setup with no problems :?
Yea the car has been perfect for months and still runs just fine but, it did throw that code so I'll have to look into it some more.I'm using an obd2 distributor on my setup with no problems :?
I can't see this setup making 300whp at that boost level ..
it's pretty close to what it should make..
I bet it has too much timing in it.
it's pretty close to what it should make..
I bet it has too much timing in it.
Idk man I've read a lot of forums on people making around 280-290whp at 16psi and the tuner even said they tuned a stock y8 and it made 220whp on like 12-14psi.I can't see this setup making 300whp at that boost level ..
it's pretty close to what it should make..
I bet it has too much timing in it.
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.
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.
Can we have a look at the timing maps on the tune? Download S Manager if you haven't already, pull up the timing maps and let's have a look see. I'd bet there's probably 12-14 degrees of timing in it which will literally kill it. Power wise and internally as well.
maybe the garrett is just that much better of a design than the maxpleeding turbs.?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.
First off, thank you for the thoughtful response.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.
This was on a Mainline Hub dyno and yes I'm looking to put the car on e85 so I can hit 350-400whp on a flex-fuel setup.
Yea on the VTEC map at 16psi and 7500 rpm, which is what the limiter is at, it's 13.65* of timing. The thing is I just talked to the tuner and he said he worked his way up to that much timing and that's the most power the car made. He said while we were there that the car wasn't really responding to more boost/timing so it felt like something else was holding the car up. My goal for the car is to get a flex setup and run e85 to make 20-22psi and hopefully end up with 350-400whp. However, with it making this power at this boost 20psi would make maybe 300whp which really doesn't seem right.Can we have a look at the timing maps on the tune? Download S Manager if you haven't already, pull up the timing maps and let's have a look see. I'd bet there's probably 12-14 degrees of timing in it which will literally kill it. Power wise and internally as well.
Im sure it is but since this turbo too big for the car and is making the 16psi it should make at least decent power. Right?maybe the garrett is just that much better of a design than the maxpleeding turbs.?
I would look at a higher energy coil, even doing an external, or COP conversion.
I'd also do a larger TB.
A big factor in your power is the flow of pressurized air also needs to be maximum Volume.
You can have 16psi and 100 cfm, and make lower power, and you can have 10psi with 600 cfm.
That turbo is unlikely flowing the same CFM as the same "size" in a higher quality would, not a knock, just a basic of less is less.
With your lowered static compression, you will need a higher volume of air to bring it up to it's potential.
Just a 2¢ opinion.
*Edit Did the tuner take off the iar filter while tuning?
I've know a few who would, some don't, just curious.
I'd also do a larger TB.
A big factor in your power is the flow of pressurized air also needs to be maximum Volume.
You can have 16psi and 100 cfm, and make lower power, and you can have 10psi with 600 cfm.
That turbo is unlikely flowing the same CFM as the same "size" in a higher quality would, not a knock, just a basic of less is less.
With your lowered static compression, you will need a higher volume of air to bring it up to it's potential.
Just a 2¢ opinion.
*Edit Did the tuner take off the iar filter while tuning?
I've know a few who would, some don't, just curious.
Hub dyno's will usually show a bit higher than rollers will, but are very accurate.First off, thank you for the thoughtful response.
This was on a Mainline Hub dyno and yes I'm looking to put the car on e85 so I can hit 350-400whp on a flex-fuel setup.
You don't get the real life friction loss of rolling tires clamped the hell down with HD ratchet straps on hub dynos. The correction algorithm will get close, but usually dont simulate the full picture, so your whp at the hubs will show to be a bit higher.
Doing a rip on a roller will likely show 310-315, so you're right where you should be!
When the tuner said it wasnt responding to more boost, what does he mean? How much more boost did he try?
I wonder if he likely stopped going higher to avoid det on pump gas, going beyond 300ish whp starts to get into that "sketchy" territory, regardless if you use boost or timing to try and go higher. Definitely use more boost for power, over timing increases on these engines, your head gasket and bottom end bearings will thank you.
13.5 degrees at 16psi 7k is a spicy for a D!
I'm tuned at 15.75 degrees at 8psi 7500rpm!
At 20psi, I'm at 7 degrees 7500rpm, and it pulls like a raped ape.
I wonder how much experience your tuner has with D series engines? These engines want lower timing and higher boost, compared to engines that have larger bore/piston diameters.
Possibly, maybe lol.maybe the garrett is just that much better of a design than the maxpleeding turbs.?
Did you mean 400whp here? Cause you're already over this power level lol.However, with it making this power at this boost 20psi would make maybe 300whp which really doesn't seem right.
Honestly because of the lack of timing we can throw at these engines on pump or E85 due to D series architecture limitations, boost is used to make power safely over any increases in timing, which should stay conservative to keep cylinder pressure dwell to a minimum to avoid popping head gaskets.
Im a little confused you say that the hub dyno is close but say that if i did a rip on one i would put down 300-315 which is a 70-80hp difference. The tuner also used to have a roller dyno and I asked what the difference between his current hub dyno was and a dyno jet/mustang dyno and he said it should be somewhere in the middle. Again he said that the car should be making at least more than 235 at 16psi. He's tuned a ton of hondas and even tuned a del sol that made 457whp at 22psi on the old roller dyno. Also, when he was saying responding to boost he meant working up to 16psi which he said was the limit for safety on pump gas. I plan on putting a flex sensor in soon and shooting for 350-400 but, if the car isn't behaving right I want to get that worked out before just shoving boost in it.Hub dyno's will usually show a bit higher than rollers will, but are very accurate.
You don't get the real life friction loss of rolling tires clamped the hell down with HD ratchet straps on hub dynos. The correction algorithm will get close, but usually dont simulate the full picture, so your whp at the hubs will show to be a bit higher.
Doing a rip on a roller will likely show 310-315, so you're right where you should be!
When the tuner said it wasnt responding to more boost, what does he mean? How much more boost did he try?
I wonder if he likely stopped going higher to avoid det on pump gas, going beyond 300ish whp starts to get into that "sketchy" territory, regardless if you use boost or timing to try and go higher. Definitely use more boost for power, over timing increases on these engines, your head gasket and bottom end bearings will thank you.
13.5 degrees at 16psi 7k is a spicy for a D!
I'm tuned at 15.75 degrees at 8psi 7500rpm!
At 20psi, I'm at 7 degrees 7500rpm, and it pulls like a raped ape.
I wonder how much experience your tuner has with D series engines? These engines want lower timing and higher boost, compared to engines that have larger bore/piston diameters.
No I meant 300whp bc I'm making 235 right now. I know my setup isn't the most efficient but, there are countless people making over 350whp on around 20-22psi. Since my car is making 235 at 16psi there is no way it would jump to 350 with just 4psi on e.Did you mean 400whp here? Cause you're already over this power level lol.
Honestly because of the lack of timing we can throw at these engines on pump or E85 due to D series architecture limitations, boost is used to make power safely over any increases in timing, which should stay conservative to keep cylinder pressure dwell to a minimum to avoid popping head gaskets.
I totally agree on the china turbo flowing less. I was looking into a bigger TB considering the stock one is so tiny, maybe a 70mm and port match the manifold. Also, the car has no air filter just a screen and they even pulled that to check turbo shaft play and then made some pulls with it still off.I would look at a higher energy coil, even doing an external, or COP conversion.
I'd also do a larger TB.
A big factor in your power is the flow of pressurized air also needs to be maximum Volume.
You can have 16psi and 100 cfm, and make lower power, and you can have 10psi with 600 cfm.
That turbo is unlikely flowing the same CFM as the same "size" in a higher quality would, not a knock, just a basic of less is less.
With your lowered static compression, you will need a higher volume of air to bring it up to it's potential.
Just a 2¢ opinion.
*Edit Did the tuner take off the iar filter while tuning?
I've know a few who would, some don't, just curious.
Dude, I'm so sorry I must have been smoking crack...Im a little confused you say that the hub dyno is close but say that if i did a rip on one i would put down 300-315 which is a 70-80hp difference. The tuner also used to have a roller dyno and I asked what the difference between his current hub dyno was and a dyno jet/mustang dyno and he said it should be somewhere in the middle. Again he said that the car should be making at least more than 235 at 16psi. He's tuned a ton of hondas and even tuned a del sol that made 457whp at 22psi on the old roller dyno. Also, when he was saying responding to boost he meant working up to 16psi which he said was the limit for safety on pump gas. I plan on putting a flex sensor in soon and shooting for 350-400 but, if the car isn't behaving right I want to get that worked out before just shoving boost in it.
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.
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...
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.
Off the top of my head, these are the things that come to mind to check.
- 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.
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...?
Runs good and definitely pulls good but, I built the car with the 350-400whp goal in mind and if somethings wrong with the car I want to fix it and get it where I've always wanted it to be. Yea a number doesn't mean anything but, if this is what 235 feels like 350-400 is gonna be fantastic!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...?
1 - 20 of 39 Posts
- This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Honda D Series Forum
A forum community dedicated to the Honda D Series engine owners and enthusiasts. Come join the discussion about performance, builds, reviews, turbos, and more!
Full Forum Listing
Explore Our Forums
