Undergoing and coming to completion

[Junior392]

Over the course of this winter I have done a small build and it is coming to a finish. Current build consist of 225 Walbro, 550 injectors, AEM fuel rail, JMF Sheet Metal intake mani, Tubular exhaust, FMIC, 3”GM MAFS, Stock internals(valves, retainers, guides…) / milled head with 280 cams, and a SAFC. What I have left is to set timing to Top Dead Center and install my larger output coil. What I am asking is, How do I tune or can I tune my SAFC to accommodate these mods? I simply can’t afford a Standalone unit at this time so that is out of the picture. Has anyone have any experience with them? Hoping that I you guys could help me out and set me into the direction.
Thanks in Advance

 

[Lonewolf64]

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Get one of Keydiver's chips to accommodate your mods, a datalogger, a wideband O2 sensor, and your SAFC. These things together should let you put a reasonable tune on your car.

Are you looking to make ridiculous power? Are you spinning your engine past 9000rpm? If not, get rid of those 280 cams as they are completely useless for your setup. You are sapping all of your low and mid range power for top end that you can't even use unless you are spinning past 9000rpm. I don't see any mention of a fuel pressure regulator either, which you will definitely need. Also, is this on your stock 14b? Running a SMIM and 280 cams on a 14b is one of the most ridiculous things I've heard. It sounds like your build is just a variety of parts haphazardly thrown into the car.

 

[Junior392]

Quote:
Get one of Keydiver's chips to accommodate your mods, a datalogger, a wideband O2 sensor, and your SAFC. These things together should let you put a reasonable tune on your car.

Are you looking to make ridiculous power? Are you spinning your engine past 9000rpm? If not, get rid of those 280 cams as they are completely useless for your setup. You are sapping all of your low and mid range power for top end that you can't even use unless you are spinning past 9000rpm. I don't see any mention of a fuel pressure regulator either, which you will definitely need. Also, is this on your stock 14b? Running a SMIM and 280 cams on a 14b is one of the most ridiculous things I've heard. It sounds like your build is just a variety of parts haphazardly thrown into the car.



I appreciate your advice on the Keydriver will have to look into them. I have not raised that rev limiter past the stock allowance and don’t plan on it either. I apologies, I left some components out via the big 16g currently at 22psi of boost, an AEM True Boost and Wideband, Full 3" Exhaust turbo back, and a catch can that I have the head breather and pcv valve connected to. Also the 3"GM MAFS is after the turbo on the cold side next to the TB. The cams that are installed are race grinded 280s (mid to high end). I originally wanted 272s but I was talked into these 280s. I was told that the race grind 280 will allow for mid to high end power. I am setting up for 1/4 mile racing. Last summer I ran 1 13.2 with a trap speed of 105mph. That setup was with out the JMF Intake manifold, header, and cams. I am shooting to break 11s. Again I appreciate you guys help and any info I do get I will use and consider.
Thanks Again in Advance

 

[Lonewolf64]

I still stand by the fact that 280s are absolutely useless for your setup. You will go slower on them then on a set of 272s or even 264s. I personally run 264s with my evo3 16g and find them perfect for street use. At the strip, you may benefit by going with 272s but most definitely not 280s.

If this is a vr4 it will be difficult to break 11s on that setup but possible. You definitely need to switch out your cams to 272s at the most and consider dropping the SAFC/keydiver chip combo and upgrading to DSMlink. Timing control is necessary to squeeze the final bits of power out of a setup and the keydiver chip/SAFC does not provide for it.

Also, if you are running raised compression ratio in your block, that is another reason to go with a better engine management system, because a keydiver chip and SAFC may very well cause you to see too much timing at reasonable boost levels and uncontrollable knock.

 

[Terry Posten]

The cams will not work for you. I have BC280s on my setup and wish I would have bought the 272s.

I am running a 2.3L pushing a PTE 6152R snail w/all the supporting mods.

Your 16G revving to 7000 will not even really hit the power band.

You reall should drop down to the 272s and the very least.

Good luck.

 

[NateCrisman]

Agreed on the cams, 272's would be ideal IF you were planning to run the engine out to 8000. More than your cam choice, I feel you are putting a handicap in the mix by not raising your rev limit. Your mechanical part choices: big cams, sheetmetal intake manifold are not going to show up much benefit when you have to make your shift before 7000rpm. Those parts make the most power increases at the very top of the powerband.

I suggest you at the very least change your chip to one with an 8200rpm rev limiter and plan to make your gear changes at the track at 7600 or 7800.

The other suggestion of going with a more tunable engine management system in place of the chip/afc would also be of major benefit. Getting the most power out of your specific combination of hard parts always requires fine tuning of the timing map. with an AFC/Chip your tune is a juggling act of AF/timing/airflow/fuel pressure.

If you want to go 11's on a 16g in a GVR4, it's going to take a nearly perfectly fine tuned setup with no issues. While it's possible to do it on an AFC/Chip, a DSMlink or DS-Map user tunable setup will be the best investment you can make.

 

[Dialcaliper]

Here is the AMS cam test

The engine in question is a 2.0L with a 35R, but you can kind of tell what's going on by where the peak power points are. The bottom end is kind of diluted by the huge turbo, but the characteristics of the 280's still show through.

Here's another evo test by Turbo Magazine. 35R again, but you can still see the difference.

The 280 cams don't even start picking up until over 4500-5000 RPM, and put the engine's peak power way up in the 8000-9000 RPM range. 5000-6000RPM going to be where your big 16G has already started wheezing.

Will you make a higher power number on a dyno? Probably, but both your peak torque and your powerband will be from 5000-6000 RPM which means it will be a complete slug below that. To give you an idea about drivability, bouncing off the 7500 RPM rev limited in first, shifting to second will drop the engine back down to about 4500 RPM. If you short shift when the turbo starts wheezing at 6000, you'll be bogging the engine at 3500 RPM. So with the 280's, your car will be a complete dog unless you're bouncing off the rev limiter

Here's a dyno of a Big 16G DSM. As you can see, the stock cams hit peak torque at 3200 RPM when the turbo comes on and starts dropping off at 4500. At Up at 6000, the turbo is starting to choke off and blow hot air.

Here are some more Evo plots with HKS 272 and 280's on the stock Evo 8 turbo. Keep in mind that the stock Evo 8 turbo supports significantly more flow than a Big 16G (Its very close to an 18G if you were to compare it by flow potential)

Its questionable whether you even need 272's. A 264 or 264/272 are a much better match for that turbo if you're willing to fiddle with cam gear settings. Your current turbo and cams simply are not a good match.

Cams behavior overall is pretty much independent of boost level, turbo choice, and pretty much everything else except some effects from head porting, and of course increased displacement.