RB26 vs RB28 Vcam Dyno result

[Deza3000]

Thought I'd make a post for reference for people planning their next build who are going for a stroker or vcam. Theres not enough tangible info on the net when it comes to comparing a stock 26 to a 2.8 vcam with NOTHING else being modified in the process. Its the most apples to apples comparison you will be able to get

Mods before 2.8 vcam:

- 2859r-9s
- Fujitsubo Turbo back exhaust
- Stock Dumps
- Static Bleed valve (non adjustable)
- Fuel stuff - Injectors, pump etc...
- The rest is factory - i.e. intercooler, intake, head, cams, manifolds etc..
- E85 tune on a power fc (yesss i still use fc ? )

Mods After 2.8 Vcam:

Just the Billet 2.8 stroker and Vcam - No porting the heads, no mods to exhaust/intake, just the stroker and vcam with the same bleed valve (unchanged in this dyno run)

 

 

[joshuaho96]

VCAM step 1?

[djvoodoo]

Why would you not get an electronic boost controller or use ECU boost control if going all out on Vcam and a stroker? You spend 15-20K on the engine but not an extra $500 on a good boost controller?

I had an unopened Rb26 with -9's and was making 20.5 psi by 100km/h on pump 98 (3970 rpm on a 34R). 

Your boost curve look s like a -5 turbo on a standard 2.6 without E85.

Edited July 25, 2020 by djvoodoo

[Deza3000]

4 hours ago, joshuaho96 said:

VCAM step 1?

Yep Step 1

 

1 hour ago, djvoodoo said:

Why would you not get an electronic boost controller or use ECU boost control if going all out on Vcam and a stroker? You spend 15-20K on the engine but not an extra $500 on a good boost controller?

I had an unopened Rb26 with -9's and was making 20.5 psi by 100km/h on pump 98 (3970 rpm on a 34R). 

Your boost curve look s like a -5 turbo on a standard 2.6 without E85.

I probably should of added more context. I'm not a fan of EBCs, as per my tuners recommendations, these arent the best in terms of reliability, better off getting a haltech/motec and control boost using the ECU. We do control the boost using a static bleed valve set to the desired boost pressure. We didnt really want the gate to be forced shut for longer just to make a few extra kw up top as this increased cylinder pressure which as a result puts the car in a medium risk category. 

Was your car tuned on 5th gear or 4th? I have driven multiple cars with similar setups (differences being -5s, GTX -5s and my -9s), all VCam, 98 and e85 builds. I can tell you now that this car was the most responsive out of the lot, though tapered off on the top end. I should also add, after going with a free flowing exhaust, the car held boost for longer with no change in boost controller or boost. 

Edit: Just did a quick calculation: Yours would have been run in 4th

4th Gear @100kph is around 3790rpm on an 18inch wheel 275/35/18
5th Gear @100 kph is around 2900 rpm
Seeing as it hit 20psi around 117kph 5th gear, its coming on full at 3380rpm. 

Edited July 25, 2020 by Deza3000

[Ben C34]

Being unsure of ebc's reliability is a new one!

[Deza3000]

30 minutes ago, Ben C34 said:

Being unsure of ebc's reliability is a new one!

Reliability may be the wrong word.. I meant reliability and longevity of the motor. Given the application, it provided no benefit switching to an EBC.  Its still a street car. I'd rather save up and go flex and have a Motec control boost and maybe the VCam as well. 

 

Edited July 25, 2020 by Deza3000

[robbo_rb180]

Benefit of a quality ebc or ecu boost control is preventing wastegate creep as most wastegates will start opening before target is reached. There can be a noticable difference as wastegate will not open before that target is reached especially on external gates with adding pressure to the top port. 

[Butters]

Any chance of getting the same graph with RPM ? 

 

Thanks for sharing. Lots of peoples opinions on this topic but as you say little back to back data without other changes. 

 

I am also with you on the bleed valve, used one for 12 years on one setup. Works great.  

Had some really mixed results with ebc over years. Now using ECU on another setup and its good but not a game changer. 

[djvoodoo]

2 hours ago, Deza3000 said:

Yep Step 1

 

I probably should of added more context. I'm not a fan of EBCs, as per my tuners recommendations, these arent the best in terms of reliability, better off getting a haltech/motec and control boost using the ECU. We do control the boost using a static bleed valve set to the desired boost pressure. We didnt really want the gate to be forced shut for longer just to make a few extra kw up top as this increased cylinder pressure which as a result puts the car in a medium risk category. 

Was your car tuned on 5th gear or 4th? I have driven multiple cars with similar setups (differences being -5s, GTX -5s and my -9s), all VCam, 98 and e85 builds. I can tell you now that this car was the most responsive out of the lot, though tapered off on the top end. I should also add, after going with a free flowing exhaust, the car held boost for longer with no change in boost controller or boost. 

Edit: Just did a quick calculation: Yours would have been run in 4th

4th Gear @100kph is around 3790rpm on an 18inch wheel 275/35/18
5th Gear @100 kph is around 2900 rpm
Seeing as it hit 20psi around 117kph 5th gear, its coming on full at 3380rpm. 

But it's not hitting 20 psi at 117. Your graph shows more like 18 psi. 20psi prob happens another 150 rpm later, and considering it's in 5th there is more load on the motor.

Im guessing your wastegates on -9's are 1bar adjustable actuators. Why not just wind in some preload into them? 

Edited July 25, 2020 by djvoodoo

[Deza3000]

15 minutes ago, robbo_rb180 said:

Benefit of a quality ebc or ecu boost control is preventing wastegate creep as most wastegates will start opening before target is reached. There can be a noticable difference as wastegate will not open before that target is reached especially on external gates with adding pressure to the top port. 

Yea I do agree with you, however wastegate creep is a result of excess cylinder pressure, by product of insufficient flow on the exhaust housing.

In this setup, my -9s arent particularly big turbos, forcing the wastegate shut for longer can almost double cylinder pressure up top as exhaust gasses arent able to exit quick enough. -5 turbos with a Bleed valve hold boost all the way through without having to force the wastegate shut with an ebc. That being said, Ill send through another dyno sheet of my car after switching from a twin pipe exhaust to a straight through, ended up holding more boost uptop. 

As you said, EBC probably benefits more with external gates and big 600kw power builds. Ultimately rather control boost via a good ECU.

This is all my opinion, i guess some setup has worked better for others. 

 

9 minutes ago, Butters said:

Any chance of getting the same graph with RPM ? 

 

Thanks for sharing. Lots of peoples opinions on this topic but as you say little back to back data without other changes. 

 

I am also with you on the bleed valve, used one for 12 years on one setup. Works great.  

Had some really mixed results with ebc over years. Now using ECU on another setup and its good but not a game changer. 

Ill see if I can!

Not a problem! Glad I could help.

So have I, had plenty of discussions about EBC, most recommend ECU controlled or just a bleed valve

[Deza3000]

5 minutes ago, djvoodoo said:

But it's not hitting 20 psi at 117. Your graph shows more like 18 psi. 20psi prob happens another 1-200rpm later, and considering it's in 5th there is more load on the motor.

Im guessing your wastegates on -9's are 1bar adjustable actuators. Why not just wind in some preload into them? 

Yea they are the dodgy 1 bar actuators garret gives for free. Will look into it! Im all for more response! 

[djvoodoo]

Just now, Deza3000 said:

Yea they are the dodgy 1 bar actuators garret gives for free. Will look into it! Im all for more response! 

Sorry bro, i just don't really understand the reasoning to spend 5-6K on Vcam and a 2.8 stroker, only to use a $30 bleed valve and a Power FC.

You could get much more better results by doing it right - Halaltech/ Motoec/ Link -Whatever and ECU boost control

[Deza3000]

16 minutes ago, djvoodoo said:

Sorry bro, i just don't really understand the reasoning to spend 5-6K on Vcam and a 2.8 stroker, only to use a $30 bleed valve and a Power FC.

You could get much more better results by doing it right - Halaltech/ Motoec/ Link -Whatever and ECU boost control

Nahh i understand where you're coming from! Long story short, oil pump died and i had to build a motor. I had limited funds and so i just purely stuck to the 2 upgrades that would make the most difference. I only got the Vcam cause i got it for cheap, 3.9k including shipping and import tax so i jumped on it. Racepace installed/fitted the vcam at no extra cost, My Crank was damaged so I went 2.8. I also spent ecu money on preventative maintenance stuff so 9l Baffled circuit sump, Nitto Oil pump. 

 

It was snow balling when i started adding bolt ons, i.e. more boost means needed to do fuel system so another 5k, needed a new front mount as mine was still stock and hit its limit +3k, dumps HPI +700, Haltech + Trigger kit 2k+, if i went haltech id go flex, another 300 etc... Its money i didnt have. 

Edited July 25, 2020 by Deza3000

[Butters]

Lolz... my 12 year old setup still runs powerfc too !  

Works great, runs 9's on stock engine with metal HG and studs. 

I put a link in it, made zero difference .....  except my tuner was happier. 

Back to the powerfc now though for general duties and link is in street car.

 

djvoodoo, show me a back to back graph where an ecu makes more power swapping from powerfc ?

Data , facts and such. 

[djvoodoo]

13 minutes ago, Butters said:

Lolz... my 12 year old setup still runs powerfc too !  

Works great, runs 9's on stock engine with metal HG and studs. 

I put a link in it, made zero difference .....  except my tuner was happier. 

Back to the powerfc now though for general duties and link is in street car.

 

djvoodoo, show me a back to back graph where an ecu makes more power swapping from powerfc ?

Data , facts and such. 

Not about power mate. It's about reliability and tuning resolution. Tell me a Power FC that does inbuilt Knock control and can retard timing etc or can put a car in safe mode if a certain limit is reached.

Show me a Power FC that can do motorsport launch control or add multiple external inputs such as additional engine protection sensors, Wideband sensors, CAN Bus displays etc.

All the Power FC does is "blink" the engine warning light...

[Butters]

2 minutes ago, djvoodoo said:

Not about power mate. It's about reliability and tuning resolution. Tell me a Power FC that does inbuilt Knock control and can retard timing etc or can put a car in safe mode if a certain limit is reached.

Show me a Power FC that can do motorsport launch control or add multiple external inputs such as additional engine protection sensors, Wideband sensors, CAN Bus displays etc.

All the Power FC does is "blink" the engine warning light...

 Cool, no argument there, the extra feature set is nice. 

You just suggested he would get a better result.  The only thing in the list above that could do that really is the tuning resolution, which makes a very small difference on a simple engine, my opinion ... not fact   

12 years, 100s of drag passes, lots of events, stock motor from 1990 challenges your reliability statement a bit  

To be fair to you i do have a dash with logging, warning etc. 

[djvoodoo]

10 minutes ago, Butters said:

 Cool, no argument there, the extra feature set is nice. 

You just suggested he would get a better result.  The only thing in the list above that could do that really is the tuning resolution, which makes a very small difference on a simple engine, my opinion ... not fact   

12 years, 100s of drag passes, lots of events, stock motor from 1990 challenges your reliability statement a bit  

To be fair to you i do have a dash with logging, warning etc. 

My better result reference was more around proper boost control, but i mean - He's built a 2.8 Stroked RB26 with Vcam on an R34 GTR.. Go the ECU with the safety features that saves engines man.

[Butters]

I am just a bit cautious around the hype.  These Nissans been making good power for a long time on some pretty basic ecus. Seems you get crapped on if you don't drop $4k on an ECU and all the setup.  In some ways I regret doing it, its money that could have gone into other area's.  I don't have flex or launch setup yet, maybe when i do I'll see more value from it. 

[Deza3000]

18 minutes ago, Butters said:

 Seems you get crapped on if you don't drop $4k on an ECU and all the setup.  

This^^^ Hence why I emphasised the "yes I still used fc"

 

40 minutes ago, djvoodoo said:

My better result reference was more around proper boost control, but i mean - He's built a 2.8 Stroked RB26 with Vcam on an R34 GTR.. Go the ECU with the safety features that saves engines man.

Ill admit the features are nice, will do an ECU upgrade when the time comes. As stated before, I budgeted towards preventing oiling issues rather than an ecu.  The % of GTRs that have died from oiling issues is far greater than those with basic ECUs with limited safety. 

[Murray_Calavera]

I've had my Haltech engine protection kick in twice now. Once during a drift event when I had a lean out. Probably saved the motor. 

Another time when my stupidity resulted in me having the wastegate perma-closed. Having infinity boost most certainly would have done some damage. The engine protection kicking in amazingly well and the boost spike only hit about 22ish psi with no harm done. 

Yeah I love my Haltech. I think it is money well spent. 

Sometimes having an ECU is like insurance - if you never make a claim it's money wasted right? But when it saves your ass again and again, it really feels priceless.