DOD Cam Swap (formerly known as Preliminary Feedback On New Era G8GT Cam in an LS4)
#27
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Thanks everyone for all of the feedback! It's a work in progress, but I'll get 'er done.
I'm sure it could be done, but you'd have to make your own system to mount it. And yeah, the header whistle is annoying and the crossover plumbing cleary did not have to be as close to the throttle as it was.
I'm pretty well sold, so the next time I need rubber I'm moving up. How have those tires done for wear?
Hey, I know that you bump around a lot of forums. I see that some people say that you have to upgrade injectors above 80% and others say that as long is it's not for a long time (ie circle track/top speed racing), a 90% duty cycle is fine. Any thoughts? I'd like to keep the stockers for now, but I don't want to frag anything.
For sure. It was a nice relaxed atmosphere. Just don't make fun of my paint... all of you detail guys out there have way more patience than me. I know that it's not perfect and I park in busy parking lots all of the time.
Exhaust is further down the list after some traction work. I have a Summit gift card, so I think I'm gonna get a plain jane $30 cutout for track times and the occasional weekend cruise.
You lauch with TC on, right? Do you ever get TC hits? I'm thinking that if I practice launching with TC on and don't get any hits, then I'm doing well.
For sure. It was a nice relaxed atmosphere. Just don't make fun of my paint... all of you detail guys out there have way more patience than me. I know that it's not perfect and I park in busy parking lots all of the time.
You lauch with TC on, right? Do you ever get TC hits? I'm thinking that if I practice launching with TC on and don't get any hits, then I'm doing well.
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from my experience at the track, when launching i go 1/4-1/3 throttle out of the gate then a second after go 3/4 then WOT, you can feel the limits of how much throttle you can give it. my launch felt so good and with only going 1/4-1/3 throttle off the line i still got a good 60ft time, just takes practice, launching on the street compared to the track is way way different lol. i would say try some drag radials and some of the block you put in the back springs.
Last edited by 94ss06gxp; 06-18-2010 at 12:42 PM.
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Hey, I know that you bump around a lot of forums. I see that some people say that you have to upgrade injectors above 80% and others say that as long is it's not for a long time (ie circle track/top speed racing), a 90% duty cycle is fine. Any thoughts? I'd like to keep the stockers for now, but I don't want to frag anything.
Our stock injectors are ~28 lb/hr, and should support about 380 crank hp at an 80% duty cycle.
Just for comparison, I think my Subie comes stock with 42 lb/hr injectors (440 cc/min), so they're close to 80% duty cycle stock (need to buy new tuning equipment and run some logs, so this is just an estimate). If I want to hit 300whp safely, I'll probably have to bump those up to ~60 lb/hr.
#33
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from my experience at the track, when launching i go 1/4-1/3 throttle out of the gate then a second after go 3/4 then WOT, you can feel the limits of how much throttle you can give it. my launch felt so good and with only going 1/4-1/3 throttle off the line i still got a good 60ft time, just takes practice, launching on the street compared to the track is way way different lol. i would say try some drag radials and some of the block you put in the back springs.
I've heard numbers between 80% and 85%. If the duty cycle is too large, the solenoids in the injectors can overheat and stick. For a DD, especially one that sees cold temperatures, I'd size the injectors for the lower end of the range.
Our stock injectors are ~28 lb/hr, and should support about 380 crank hp at an 80% duty cycle.
Just for comparison, I think my Subie comes stock with 42 lb/hr injectors (440 cc/min), so they're close to 80% duty cycle stock (need to buy new tuning equipment and run some logs, so this is just an estimate). If I want to hit 300whp safely, I'll probably have to bump those up to ~60 lb/hr.
Our stock injectors are ~28 lb/hr, and should support about 380 crank hp at an 80% duty cycle.
Just for comparison, I think my Subie comes stock with 42 lb/hr injectors (440 cc/min), so they're close to 80% duty cycle stock (need to buy new tuning equipment and run some logs, so this is just an estimate). If I want to hit 300whp safely, I'll probably have to bump those up to ~60 lb/hr.
Actually dude, this might not be too big of a deal. At the kind of manifold vacuums that I'm seeing, our injectors flow about 27.6lbs/hr. Stock LS2 injectors flow just over 33lbs/hr at the same vacuum, and they should be fairly easy to pick up lightly used. I'm watching some on EBay now. They also shouldn't jack up the low end. I'm not even sure I'll need them until I hit up the wideband and figure out what's going on.
#34
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Here's my new TB adapter. I If you remember, I just punched out the nuts for the bottom two bolts, and just used modified washers and nuts to retain the TB on the bottom. So, I don't need to have seperate holes to account for the difference in the location of the bottom bolts between the TB and LS6 mani. It ended up being a 3/8" NPT fitting that worked with the 1/2" hose. I'm hoping that my brakes get back to at least pre-cam levels, if not stock feeling.
I also ordered a 2.5" cutout to go by the rear wheel (like others have done), some header wrap for the crossover, and some self adhesive heat shielding for the bottom half of the throttle body and my new adapter. Hopefully I'll be able to keep my intake air temps under 100 degrees now.
And now I'm gonna put the keyboard down, step away from the computer, and hit the sack.
I also ordered a 2.5" cutout to go by the rear wheel (like others have done), some header wrap for the crossover, and some self adhesive heat shielding for the bottom half of the throttle body and my new adapter. Hopefully I'll be able to keep my intake air temps under 100 degrees now.
And now I'm gonna put the keyboard down, step away from the computer, and hit the sack.
#35
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I put some pics from the swap in my original post if you missed them.
I also stumbled onto some reported specs for the cam, too:
http://forum.grrrr8.net/showthread.p...-Era-DoD-Cams=
That post has the cam at 224/232, 0.570"/0.575", 113LSA. I was told the cam was about 0.575" lift on a 113LSA with ramps that aren't super aggressive by Mike at New Era, and the duration specs match what I'm seeing from the power band, so I think they are pretty close if not dead on.
I also stumbled onto some reported specs for the cam, too:
http://forum.grrrr8.net/showthread.p...-Era-DoD-Cams=
That post has the cam at 224/232, 0.570"/0.575", 113LSA. I was told the cam was about 0.575" lift on a 113LSA with ramps that aren't super aggressive by Mike at New Era, and the duration specs match what I'm seeing from the power band, so I think they are pretty close if not dead on.