Long story short I built a G35 with a VQ35HR motor and shoe-horned two of Comp Turbos gt3071s equivalents in there for a buddy. The motor is sleeved and has 8.8:1 pistons, Tomei 272 cams, supporting mods, flex fuel. At the time Haltech did not have a a computer that would support VTC at the time so we went the reflash option and got Ecutek since they also had flex capability. As you know Ecutek is for 09+ cars so I got an 09 ECU and went though all the BS of getting that to jive in there. (Please don't flood my inbox or kill this thread asking how to do this, it's a pain, buy a Haltech.)



The car is running, and sort of tuned but the power isn't where I expected it to be. Granted the low comp pistons are not helping with its efficiency but at 20 pounds I would expect to see more than 600whp on e70. The motor is healthy and has good compression, I feel the issue is related to the cam tuning. To my knowledge the tuner left the cam timing at factory VHR settings despite these being 272s.

Does anyone have a turbo VQ and care to share their intake and exhaust cam timing maps even privately so I can compare and at least get a sense of where things should be? I know tuners never reveal the ingredients to their secret sauce but I'm only looking for a reference to see if maybe I have too much overlap or if there is something else I should be looking at. I do plan on checking the valve lift safety tables and making sure those do not interfere but since the settings are factory I dont think this is a problem at this moment. Please feel free to share any input you might have.

 

Welcome to the forum -

I can appreciate what you're asking and being a member of this forum for however long I've been hanging around there hasn't been much credible content on variable cam timing.

I would say a large portion of our members are running OEM DE blocks, furthermore, very few of our members build past the 450hp mark. Of the handful of members that are built most don't do their own tuning and of the few that are built and do their own tuning it's such a undiscussed topic that no significant information has been discussed or at least discussed to a point that would be beneficial to you.

In my dealing with a few individuals who are seasoned tuners the theme has always been 'guess & check' as every engine is going to be different.

From my understanding of variable valve control/timing is going to be mostly beneficial to your peak torque and not your peak horsepower figure. But I would also agree at 506ft*lbs of torque is lack-luster. On my 17psi tune, 568hp and 544ft-lbs and I'm running 9.1:1 and 262d cams.

do you have any values in the cam timing tables at all? are you 100% sure your VTC solenoids are functioning correct? I had VTC issues when I ran my haltech and my torque was down 80 ft-lbs (IIRC) when haltech wasn't communicating with the solenoids.

I can get you baseline Haltech and possibly Link values if you like?

 

Thanks for the quick and detailed reply. This forum seemed to have the most information regarding VQ tuning so I decided to join and see if anyone might have some info beyond typical retard the timing to build boost and start advancing along the boost curve.

My only experience with variable cams are on 2JZs where cam timing does play a big part on mid range and spool but also where cam profiles are setup for boost and have minimum overlap.

Solenoids definitely work as I can see the cam trigger waveform shifting with advancement. The full retard positions are slightly different between HR and VHR so I needed to address that to make the 09 ecu happy.

I stole this from Ecutek but the values on mine should match these.

I'd like to see a map that was tuned for boost just to get an idea of the maps shape as this map has a lot of advance in the boost building areas where I'm used to these values being zero or close to. Thank you again for your rely bealljk.

 

simply my experience and happy to help.

my go to for anything tuning / engine building is HPA - these are their webinars on variable valve timing tuning. May be worth looking into a subscription if you want to get deeper into tuning.




I don't think youre going to find anyone that has a variable cam map tuned for their car. Of my three tunes I've done the tuner wasn't interested in tuning the VVT and I think they don't know enough about it. On my Haltech and on the Link I've used their canned maps for VVT.

We're happy to have you and if you can stand having us around maybe start a thread on your build, upload pictures, stories, experiences, etc.

 

I actually have a gold member account with them. Maybe I will try on their forum as well.

 

badass … I would watch the webinars - I love them and theyre informative.

 

Use discretion and at your own risk:

 

Those first two maps look like what I expected to find for boost, the second two look like NA maps. I'll try shifting the maps over like those and log the maf voltages before and after. That should give me a pretty good idea of where it's helping and where its hurting. Thanks for all your help.

 

The bottom two are from the template base file in each Link and Haltech.

I'd be interested to see what results you come up with - keep the thread updated if you don't mind!