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So I am new to big mods on cars and I’d love to put the 274 comp cam into the 5.7 but I guess I don’t even know where to start as of now... what is the first 5 things I should do to prep and get ready to install this and where and who would be a good person to go to for tuning (location, Nebraska)
 

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if you're planning on using on the street, I'd recommend a 266 cam at the most.

Even Comp recommends the 274 for stroker engines - you'll have better results with other cams.

There's folks I know with 392s that after doing the swap consider changing out to something other than the 274 they put in (again, street driven primarily)
 

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Im going to run the 274 cam. If you have the rest of stuff to run it, its great in a 5.7. For best results you need to have headers, long tube preferably, intake that can support the top end, cam phaser lockout or limiter, unlocked pcm to be able to tune it, valve springs, pushrods to handle the new valve springs, if its automatic then you need lifters, gaskets and fluids. Water pump, thermostat, belt wouldnt hurt to change also. Components are off to do the swap and its cheap insurance.
If your on a budget then go with the 6.4 or 6.2 cam. Most wont upgrade the rest of whats needed to run the 274 cam in a 5.7 and they get poor performance. But if you have the rest of the mods then it will definitely wake the engine up and out perform the stock(6.2,6.4) cams.
 

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The problem with that cam is not the duration but the installed intake centerline. Ideally you would want it at 106 or so but instead you are stuck with it being 111 or so because of piston to value clearance. This causes a dramatic loss of power in the low rpm range. Not good for a heavy car with a smallish displacement. Pistons with generous valve relives and a custom cam with a 106 ish intake centerline and similar lobes would work much better but that ain’t cheap.
 

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The problem with that cam is not the duration but the installed intake centerline. Ideally you would want it at 106 or so but instead you are stuck with it being 111 or so because of piston to value clearance. This causes a dramatic loss of power in the low rpm range. Not good for a heavy car with a smallish displacement. Pistons with generous valve relives and a custom cam with a 106 ish intake centerline and similar lobes would work much better but that ain’t cheap.
You must be use to old school engines. Ive run sbc's with 104 and love them. Use to advance a cam 4° also. But these are new engines and have VVT. The phaser makes all the difference in the world. The 274 is actually 116. Run a limiter that allows the ecu to advance and retard it 4° both ways.
Ill be setting mine up with a cam degree wheel. Should be interesting, will find out soon
 

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There's definitely better options than the 274, like the new HRT cams and custom grinds, but everyone has their own opinion. I'm very happy with my 392 cam. For a stock displacement daily driven car I didn't see any reason to run a bigger cam to get that extra 5-10 hp up top when I'm just gonna go boosted anyway and make another 100.
And I HIGHLY recommend long tubes with the cam, they go hand in hand.
 

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You must be use to old school engines. Ive run sbc's with 104 and love them. Use to advance a cam 4° also. But these are new engines and have VVT. The phaser makes all the difference in the world. The 274 is actually 116. Run a limiter that allows the ecu to advance and retard it 4° both ways.
Ill be setting mine up with a cam degree wheel. Should be interesting, will find out soon
The lobe separation angle is 116 not the intake centerline. Two different things. LSA is the angle between the intake lobe and exhaust lobe. Intake centerline is the degrees that the intake lobe is at max lift in relation to the crank. VVT changes the intake centerline as it moves the cam. The problem is that with these cams you can’t get to 106 because 111 is the minimum. With a custom cam you would simply have the cam key hole drilled in a slightly different location to get 106 when installed straight up. They also can tighten up the LSA as well. You can only go up from 111 as VVT retards the cam up to 125 or so. I think that they make an offset keyed timing sprocket that would do the same thing but again you need aftermarket pistons with large valve relifes to do this.
 

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The lobe separation angle is 116 not the intake centerline. Two different things. LSA is the angle between the intake lobe and exhaust lobe. Intake centerline is the degrees that the intake lobe is at max lift in relation to the crank. VVT changes the intake centerline as it moves the cam. The problem is that with these cams you can’t get to 106 because 111 is the minimum. With a custom cam you would simply have the cam key hole drilled in a slightly different location to get 106 when installed straight up. They also can tighten up the LSA as well. You can only go up from 111 as VVT retards the cam up to 125 or so. I think that they make an offset keyed timing sprocket that would do the same thing but again you need aftermarket pistons with large valve relifes to do this.
Can you eliminate the phaser all together and install something like and old school cam with an offset key way?
Better yet a Pete Jackson Gear Drive.
 

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You can buy a crank with multiple keyways to change the intake center line. That can be manipulated. Tight lsa will build good cylinder pressure. Ill take a pic of my cam degree kit later.
 

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Can you eliminate the phaser all together and install something like and old school cam with an offset key way?
Better yet a Pete Jackson Gear Drive.
Possibly - but I'd wonder if this would throw error codes.

The OEM setup allow + / - 18* of cam operating range (36* total excursion)
The limiters restrict ~ 1/2 of the excursion to avoid piston / valve contact due to differences in duration and the lobes' timing.
an extract from a site about the phase limiter "At the same time, by keeping up to 18 degrees of movement available, all of the wide-open throttle benefits of the cam phasing can still be retained. " (this has cam phasing limited to + / - 9* for a total of 18* total excursion)

the 'downside' to fixed cam timing would probably be a big hit to fuel efficiency. Remember the 400ci engines from the 60s and 70s - probably back to that level of fuel consumption.

The 6.1s had fixed cam timing and their mileage wasn't great 13/18 (A5) and 14/22 (M6)
 

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Notes from Comp regarding the 274 cam:
Comp's Listed Application: HYDRAULIC - Requires either added displacement or high RPM modifications in street/strip applications
RPM Operating Range: 2400 to 7400 expected

the other item ^^^ is note the operating range. a lot of street driving has you @ 1,500 - 2,500 rpm. That cam is a big hit on low end power and the redline on a stock 5.7 is 5,800 rpm.

(for reference redline on stock 392 is 6,400 rpm)

the oiling system as well as rotating assembly are the limits for redline - not intake or exhaust capacity.
 

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Possibly - but I'd wonder if this would throw error codes.

The OEM setup allow + / - 18* of cam operating range (36* total excursion)
The limiters restrict ~ 1/2 of the excursion to avoid piston / valve contact due to differences in duration and the lobes' timing.
an extract from a site about the phase limiter "At the same time, by keeping up to 18 degrees of movement available, all of the wide-open throttle benefits of the cam phasing can still be retained. " (this has cam phasing limited to + / - 9* for a total of 18* total excursion)

the 'downside' to fixed cam timing would probably be a big hit to fuel efficiency. Remember the 400ci engines from the 60s and 70s - probably back to that level of fuel consumption.

The 6.1s had fixed cam timing and their mileage wasn't great 13/18 (A5) and 14/22 (M6)
Pretty sure you can completely remove the VTT solenoid provided the correct DTCs are disabled. Easier to just disable in the tune as there is a toggle for it. Although if it is a street care why get rid of VVT as it can help make power down low and up high?
 

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the phaser has a spring inside of it as well - so w/o the VVT oil control solenoid, I'd imagine the cam could have some retardation in timing with the cam going against the the force of the valve springs.

The VVT probably is using PWM to manage oil pressure for the phaser operation, since oil pressure in the engine fully warmed up will be ~ 28 psi (idle) to 60 psi at redline.

Maybe more of that (momentarily) with quick increases in rpm
 

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the phaser has a spring inside of it as well - so w/o the VVT oil control solenoid, I'd imagine the cam could have some retardation in timing with the cam going against the the force of the valve springs.

The VVT probably is using PWM to manage oil pressure for the phaser operation, since oil pressure in the engine fully warmed up will be ~ 28 psi (idle) to 60 psi at redline.

Maybe more of that (momentarily) with quick increases in rpm
The phaser will need to be locked if VVT solenoid is disabled. Comp cam has both lockers and limiters. Not sure if anyone makes a plug for the VVT if solenoid is removed though.
 

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I wouldnt lock out the vvt. Then , yes youd probably loose some bottom end torque. Limiter will allow it to still function(some) properly and will maintain the torque at bottom end. Heres my cam degree kit, havent had a call for it lately. Most dont get it done and just run them straight up. If your after every hp then i highly recommend having it done.

995104


20200604_155143.jpg
20200604_155211.jpg
 

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The limiter keeps the exhaust valve from hitting the piston. The high installed intake centerline keeps the intake valve from hitting the piston. So you still need valve relifes if you advance the cam with a timing sprocket even if you lock the cam down. Or you need a less aggressive cam lobe. If you have a 09 car like mine you have tons more tuning options with Hp tuners if you turn off the vvt. If it’s turned on none of the VE tables respond to changes. You have to log injector pw and scale the injectors accordingly. This takes a lot of time and most tuners just turn the vvt off on these oddball years and use the VE tables. I have a 426 stroker with a comp 270 that put down 520 hp to the wheels. My cam starts to retard at 4200 rpms up to 6 degrees at redline.
 

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I wouldnt lock out the vvt. Then , yes youd probably loose some bottom end torque. Limiter will allow it to still function(some) properly and will maintain the torque at bottom end. Heres my cam degree kit, havent had a call for it lately. Most dont get it done and just run them straight up. If your after every hp then i highly recommend having it done. View attachment 995065 View attachment 995066 View attachment 995067
You would not loose bottom end by locking it out but you would loose top end.
 

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Locking it out basically turns it into a non vvt engine. So then you get no advance or retard. Both would suffer instead of letting the ecu do its thing at low and high rpm's

The factory only retards it 9° at wot. Its got a total movement of 38° total. They use it for low end torque also. Lock it out and you get no movement at all.
 

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Possibly - but I'd wonder if this would throw error codes.

The OEM setup allow + / - 18* of cam operating range (36* total excursion)
The limiters restrict ~ 1/2 of the excursion to avoid piston / valve contact due to differences in duration and the lobes' timing.
an extract from a site about the phase limiter "At the same time, by keeping up to 18 degrees of movement available, all of the wide-open throttle benefits of the cam phasing can still be retained. " (this has cam phasing limited to + / - 9* for a total of 18* total excursion)

the 'downside' to fixed cam timing would probably be a big hit to fuel efficiency. Remember the 400ci engines from the 60s and 70s - probably back to that level of fuel consumption.

The 6.1s had fixed cam timing and their mileage wasn't great 13/18 (A5) and 14/22 (M6)
I was just curious how OST Dyno is going to handle it when they do my cam swap. Now I am getting nervous about bent valves, but I know they do it all the time.
 
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