DOHC Adjustable Cam Gears

[Meph]

Results

Hey guys,

Ive been testing different combinations of settings and Ive come to a conclusion for my car.

I found that +4 exhaust and 0 intake resulted in more torque down low

+6 exhaust and +3 Intake resulted in more torque than just +4

What Ive chosen to run : 0 , 0 (stock)

What I experienced

the increase in torque was a noticeable one, the issue is that I would only feel this torque increase with load on the engine, -18" to +12 psi. below this load, at -18" to -22" the engine seemed to produce significantly less. Where i was once cruse at 1.5 injection time in town, jumped to 1.6-1.7 be because i need to give it more throttle.

I think for many eco cars out there, this mod would very well help, because when your driving your engine is loaded to say -10" to -16" normally, my Datsun will cruse at -20" on flat ground, due to the light weigh body and engine swap. I only noticed a bonus to MPG's at much higher speeds than i usually drive, where the engine is turning a higher RPM and was under more load. I changed my cams back to stock part way though a drive and noticed a significant reduction in fuel injector times when cruising at very light loads (as i most often do)


So to conclude, I did produce more torque, but not in my required engine load area. Someone with a small engine would probably have benefited from his change where it only hindered me

Thanks for the input everyone. I may get ambitions and do some more testing but for now I think Ill take a quick break from it

[EdKiefer]

Originally Posted by Meph

Results

Hey guys,

Ive been testing different combinations of settings and Ive come to a conclusion for my car.

I found that +4 exhaust and 0 intake resulted in more torque down low

+6 exhaust and +3 Intake resulted in more torque than just +4

What Ive chosen to run : 0 , 0 (stock)

What I experienced

the increase in torque was a noticeable one, the issue is that I would only feel this torque increase with load on the engine, -18" to +12 psi. below this load, at -18" to -22" the engine seemed to produce significantly less. Where i was once cruse at 1.5 injection time in town, jumped to 1.6-1.7 be because i need to give it more throttle.

I think for many eco cars out there, this mod would very well help, because when your driving your engine is loaded to say -10" to -16" normally, my Datsun will cruse at -20" on flat ground, due to the light weigh body and engine swap. I only noticed a bonus to MPG's at much higher speeds than i usually drive, where the engine is turning a higher RPM and was under more load. I changed my cams back to stock part way though a drive and noticed a significant reduction in fuel injector times when cruising at very light loads (as i most often do)


So to conclude, I did produce more torque, but not in my required engine load area. Someone with a small engine would probably have benefited from his change where it only hindered me

Thanks for the input everyone. I may get ambitions and do some more testing but for now I think Ill take a quick break from it

If you can run with that much vacuum maybe you can crank up ignition timing in a small window ( low load /1500-2500 rpm ) .

[Meph]

In my load load-lower rpm range I'm running around 36-43*, I think i can still push it but I want to build a knock sensing circuit first. With my new slightly more aggressive ignition map and lowering my a/f to 15.87:1 I just returned 35.5MPG, new record

[EdKiefer]

Originally Posted by Meph

In my load load-lower rpm range I'm running around 36-43*, I think i can still push it but I want to build a knock sensing circuit first. With my new slightly more aggressive ignition map and lowering my a/f to 15.87:1 I just returned 35.5MPG, new record

43 deg sounds pretty good but that depends on what your able to run , say max TQ mid range at 0 vac " and max boost .

Is it like,around 36@0 vac and 28-30@ boost (this will depend on how much but rough valve).

Generally could might be able to stand 8-10deg of part throttle advance , so in above it be like 45 deg max .

You could maybe make a electronic stethoscope , I have seen a few DIY on it from old electronic parts .

[Meph]

in my 1500 RPM catigory, it is -38* at about 20" and by 0" it is about 26 i think, at 2000 RPM its about -42* at 20" and 30 at 0 or something close to that. I know theres a few DIY knock kits ouit there I might try one

[EdKiefer]

Originally Posted by Meph

in my 1500 RPM catigory, it is -38* at about 20" and by 0" it is about 26 i think, at 2000 RPM its about -42* at 20" and 30 at 0 or something close to that. I know theres a few DIY knock kits ouit there I might try one

that sounds good to me, your not running retarded for sure .
what rpm range do you cruise at on Highway ?

[Meph]

i dont know why I put a negative in -38*, but I meant 38* advanced, at 60 id be at 2200 ish