Let's talk G3 hemi cams

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racerjoe

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The G3 is finally getting some love from cam manufacturers. It seemed like Comp was the only one offering cams for the G3 for a long time. Now Comp has several to offer, along with Texas Speed, MMX, Hughes, Cam Motion, Lunati, etc. I'll start by saying I can't stand how manufacturers have turned to naming their cams by stage whatever. I have to assume that started in the video game world and somehow made it over into real life. If some speaking to me refers to their junk as "mods" or stage 4.87653, I automatically stop listening.
Has anyone used any of these newer cams besides the tried and true comp XFI 224? If so, which one and how did you like it? The comp HRT cams have some decent profiles given they are designed for a stock piston.
I've searched the interwebs a bunch and the only thing I can find is people that are still running these motors in their modern cars using stock computers. Not to mention they mostly look for cams that sound good when idling and revving in a parking lot but could care less about performance.

I'll end this off by saying I don't want to hear about your billet crank, custom piston, billet head, customer solid roller cam motor that makes 1500HP on 87 octane. I want to know about a cam that works with a stock or stock replacement style piston.

Sorry to sound like an ***, but too many threads get off track from the original topic.

**Edit- I have a non-VVT 5.7
 
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If some speaking to me refers to their junk as "mods" or stage 4.87653, I automatically stop listening
Can’t help with cam choice, but I have to wholeheartedly agree with this. Or if they use the term “fully built” I’m out.
 
The G3 is finally getting some love from cam manufacturers. It seemed like Comp was the only one offering cams for the G3 for a long time. Now Comp has several to offer, along with Texas Speed, MMX, Hughes, Cam Motion, Lunati, etc. I'll start by saying I can't stand how manufacturers have turned to naming their cams by stage whatever. I have to assume that started in the video game world and somehow made it over into real life. If some speaking to me refers to their junk as "mods" or stage 4.87653, I automatically stop listening.
Has anyone used any of these newer cams besides the tried and true comp XFI 224? If so, which one and how did you like it? The comp HRT cams have some decent profiles given they are designed for a stock piston.
I've searched the interwebs a bunch and the only thing I can find is people that are still running these motors in their modern cars using stock computers. Not to mention they mostly look for cams that sound good when idling and revving in a parking lot but could care less about performance.

I'll end this off by saying I don't want to hear about your billet crank, custom piston, billet head, customer solid roller cam motor that makes 1500HP on 87 octane. I want to know about a cam that works with a stock or stock replacement style piston.

Sorry to sound like an ***, but too many threads get off track from the original topic.

I could be wrong, but since you have a pre-Eagle motor, shouldn't your topic be non-VVT cam specific too? I am assuming that the manufacturers use pretty different grinds for VVT and non-VVT cams, but maybe not?

Just tossing it out there.
 
I could be wrong, but since you have a pre-Eagle motor, shouldn't your topic be non-VVT cam specific too? I am assuming that the manufacturers use pretty different grinds for VVT and non-VVT cams, but maybe not?

Just tossing it out there.
What I have found is many offer both. Sometimes its very close to the same profile, likely just a different core for VVT. I'm sure if they are truly grinding their own cams, they could grind a non-VVT if they only advertise a VVT. I could be wrong, but that's my assumption. I'll edit my request just in case.
 
Well I can’t help you any with personal experience. But what I can tell you is I love the SOUND of the FRP Tomahawk cam. I’d have to do more research to see if they offer it for non-vvt though.

*Edit* So the tomahawk is a vvt only I guess, but FRP does offer 5-6 different non-vvt cams as well.
 
Well I can’t help you any with personal experience. But what I can tell you is I love the SOUND of the FRP Tomahawk cam. I’d have to do more research to see if they offer it for non-vvt though.

*Edit* So the tomahawk is a vvt only I guess, but FRP does offer 5-6 different non-vvt cams as well.
That’s some nice duration on that cam. Unfortunately, that LSA won’t be great for a supercharger application. But it will sure make it sound good!
 
I put together an early 5.7 with the 273 Comp Cam. Customer bought it for the build. Nice idle. Couldn't tell you about the power, as I haven't driven said customer's car. Mainly just a "cruiser" and is perfectly content with it. Personally, I've used Hughes. One is in an unfired early 5.7/Eagle head deal. Another in a 6.1 in my son's car. This one is a 232/235 @ .050, 110LSA, 106 CL. 550's lift. This one has a real nice rumpty idle. Using the appropriate Hughes suggested springs. 6.1 long block is bone stock. Using Cascar carb intake with 750DP. Needs more tuning, went 11.80 off the trailer.
 
I should also add, I've done the stock 6.1 cam in the early 5.7 with Eagle heads. No noticeable idle, but, ran very well. Have also done the 6.4 cam in the VVT Eagle 5.7 engines. Works very well too.
 
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I should also add, I've done the stock 6.1 cam in the early 5.7 with Eagle heads. No noticeable idke, but, ran very well. Have also done the 6.4 cam in the VVT Eagle 5.7 engines. Works very well too.
I agree with swinger. Especially when it comes to cost. The 6.1 and 64 cams can be had for almost half of the Comp offerings. Important if you're looking for a simple upgrade, and forking out nearly $600 for a cam is just out of the question. I've seen used 6 1 cams for about half that. Not a problem going used when it comes to a roller cam, and where the issues are mostly due to lifter failure, not cam failure.

The issue I'm having is the abysmal amount of lift of even the larger 'performance' cams of late.
We're speaking of a Hemi here... NOT a wedge of any configuration. The Eagle head in stock form will nudge the 300cfm mark all the way up to .650" lift. The flow just keeps coming, unlike a wedge motor where the air is changing 3 directions and a wholesale change in shape ta boot.
My point is, if you're going to make a change, why not take advantage of this 'free air' sort to speak ??????
In the old days, adding a higher ratio rocker would get you were you wanted to be without a lot of fuss.
Not so with the G3 Hemi.. unless your name is Tony Birshoff, you're not going to ask T&D to make you a set of 1.9:1 rockers at $3500 or more because you have your sights on an Engine Masters Trophy.
I looked into Re-Ratio-ing a stock set of rockers, to alleviate the aftermarkets oversight into higher ratio rockers. Let me just tell ya, those OEM rockers are Efn HARD. Light weight, and VERT HARD! I ruined several end mills on that venture... 1.6/1.66 didn't seem so bad after that.

I've been grinding on heads for more than 30 years.. An Eagle head will BLAST past the 300cfm mark with very little attention with the stock valve (2.05). Usually 330cfm and carry it to 700".
I've got a 2016 Eagle on my flowbench, right now that's tickling the 360cfm realm (2.14) and keep going beyond .750".
Now, in keeping with racerjoes request, I'll stop there.. I just wanted to offer some prospective to the immense capabilities of this engine (cyl head design) not to mention they're enormous contribution to efficiency. two quench pads, cross-flow design, and TWO spark plugs !

As far as the cam companies. .. well, the efficiency of these engines limits the amount of 'area' in the lobes, especially around TDC where there's very little piston movement and the chambers ability to scavenge due to cross-flow. After that, you can only accelerate a valve (opening rate) so fast.. as it is, many of the Hemi springs are approaching 500lbs/inch for even modest profiles. (in balance with your typical bracket cam) When duration @ 050 is 228°, you simply run out of lobe before you can get much over .600".

Unfortunately, Joe, though options are better, the budget minded guy is still limited to drop in cams (unless you're changing springs) and keeping the PCM happy. Good thing you're in the south, us here in Kalifornia are FOOKED on this kind of thing. Bi-annual smog tests and the pcm HAS to have a stock tune.
If it were me, Joe, 6 1 or 6 4 cam and look for someone offering a higher ratio rocker someday.
Also too, if $2000 doesn't scare you much, look into the Holley Terminator X Max and let it learn. (assuming this is a swap)
 
Last year at the Indy Cylinder Head swap, I bought four 6.1 cams, low mile take outs, for 200 bucks. Score! @'63GT , what do you think of the exhaust side on the Eagles? I talk to a local guy who's been messing with Eagles. Says he's not impressed with the exhaust port.
 
Last year at the Indy Cylinder Head swap, I bought four 6.1 cams, low mile take outs, for 200 bucks. Score! @'63GT , what do you think of the exhaust side on the Eagles? I talk to a local guy who's been messing with Eagles. Says he's not impressed with the exhaust port.
The Exh ports are less than impressive, for sure. But I refuse to throw the baby out with the bath water.
What they come down to is, grind out to the gasket (top arc only) but leave the bottom as is.(size wise)
And then grind accordingly on the roof to blend into that new size. (make sense? )
The pic below is of a head I did in 2018. the goal was to reach 230cfm, that one was in he 226 range.
The pic is kinda skewed by the lens, but hopefully you'll get the idea.

20181008_141155.jpg
 
The Exh ports are less than impressive, for sure. But I refuse to throw the baby out with the bath water.
What they come down to is, grind out to the gasket (top arc only) but leave the bottom as is.(size wise)
And then grind accordingly on the roof to blend into that new size. (make sense? )
The pic below is of a head I did in 2018. the goal was to reach 230cfm, that one was in he 226 range.
The pic is kinda skewed by the lens, but hopefully you'll get the idea.

View attachment 1716039594
Thanks for that!!
 
Man this thread is right up my alley. Used to hang out here and over on Moparts back when I was bracket racing a W2 headed 340. Anyway I have a pre eagle engine and am gathering parts for a cam swap. Have a set of eagle heads, srt factory shorties and an eagle and a 392 factory intake so far. Might just use the eagle intake at first cause it will bolt right on and after I get it tuned get the MSD window switch and other mods and see how good the 392 intake is. I picked up a set of Mopar performance springs that are good to 625 lift. They are cheap. Just gotta do some more research and decide on a cam. Probably going to play around with the exhaust ports as shown above while I'm waiting to decide.
 
I'm going to be doing some flow testing on a pre-Eagle head next week sometime..
The plan is to use the OE Eagle 2.05 valves. Mainly cause they're cheap to get and an upgrade, but that's why I'm doing it.
The Exh pic is for the Eagle only. the Pre-Eagle Exh ports are very different..
 
I agree with swinger. Especially when it comes to cost. The 6.1 and 64 cams can be had for almost half of the Comp offerings. Important if you're looking for a simple upgrade, and forking out nearly $600 for a cam is just out of the question. I've seen used 6 1 cams for about half that. Not a problem going used when it comes to a roller cam, and where the issues are mostly due to lifter failure, not cam failure.

The issue I'm having is the abysmal amount of lift of even the larger 'performance' cams of late.
We're speaking of a Hemi here... NOT a wedge of any configuration. The Eagle head in stock form will nudge the 300cfm mark all the way up to .650" lift. The flow just keeps coming, unlike a wedge motor where the air is changing 3 directions and a wholesale change in shape ta boot.
My point is, if you're going to make a change, why not take advantage of this 'free air' sort to speak ??????
In the old days, adding a higher ratio rocker would get you were you wanted to be without a lot of fuss.
Not so with the G3 Hemi.. unless your name is Tony Birshoff, you're not going to ask T&D to make you a set of 1.9:1 rockers at $3500 or more because you have your sights on an Engine Masters Trophy.
I looked into Re-Ratio-ing a stock set of rockers, to alleviate the aftermarkets oversight into higher ratio rockers. Let me just tell ya, those OEM rockers are Efn HARD. Light weight, and VERT HARD! I ruined several end mills on that venture... 1.6/1.66 didn't seem so bad after that.

I've been grinding on heads for more than 30 years.. An Eagle head will BLAST past the 300cfm mark with very little attention with the stock valve (2.05). Usually 330cfm and carry it to 700".
I've got a 2016 Eagle on my flowbench, right now that's tickling the 360cfm realm (2.14) and keep going beyond .750".
Now, in keeping with racerjoes request, I'll stop there.. I just wanted to offer some prospective to the immense capabilities of this engine (cyl head design) not to mention they're enormous contribution to efficiency. two quench pads, cross-flow design, and TWO spark plugs !

As far as the cam companies. .. well, the efficiency of these engines limits the amount of 'area' in the lobes, especially around TDC where there's very little piston movement and the chambers ability to scavenge due to cross-flow. After that, you can only accelerate a valve (opening rate) so fast.. as it is, many of the Hemi springs are approaching 500lbs/inch for even modest profiles. (in balance with your typical bracket cam) When duration @ 050 is 228°, you simply run out of lobe before you can get much over .600".

Unfortunately, Joe, though options are better, the budget minded guy is still limited to drop in cams (unless you're changing springs) and keeping the PCM happy. Good thing you're in the south, us here in Kalifornia are FOOKED on this kind of thing. Bi-annual smog tests and the pcm HAS to have a stock tune.
If it were me, Joe, 6 1 or 6 4 cam and look for someone offering a higher ratio rocker someday.
Also too, if $2000 doesn't scare you much, look into the Holley Terminator X Max and let it learn. (assuming this is a swap)
Thanks for your reply. Good to see someone with some actual knowledge chiming in.

For a little background on what I'm doing- I have a running/driving car with a EFI 408 in it right now. (I'll be using the same stand alone for the G3.) I've decided to move over to the G3 world and I had a 06 5.7 sitting in my garage. I've already done some hand porting on the heads and I plan to get an "off the shelf" cam for use with the stock bottom end. I'll likely put a torqstorm supercharger on it. I considered doing the eagle head swap, but didn't think the increased compression or doubled up head gaskets would be a good idea with the supercharger. Also, the ultimate end goal would be to build a larger displacement hemi in the future. I just want to get the car swapped to this platform with what I have on hand already. There's plenty of info on my car in my build thread. If you don't want to read through it, I'm not a drag racer, more of an autocrosser and street driver. I'd be more interested in a cam that makes really good mid-range torque and HP vs max HP at 7500RPM.

Here's a couple "supercharger" cams I've looked at:

Texas speed
223/232 @.050, .582/.582, 115+3 (appears to be only a touch larger than a stock 6.4 cam)
226/235 @.050", .582/.582, 117+4

Comp
221/233 @ .050", .594/.594 116 (very similar to the TSP cam)
229/241 @ .050", .635/.635, 117

As you mentioned above, I don't know why TSP is limiting the lift on their cams. While the large Comp cam seems very healthy, I just wonder if that duration will kill low end torque. Any thoughts on this? Given I have a smaller valve and the lowly early head, wouldn't the increased lift be beneficial?
 
Thanks for your reply. Good to see someone with some actual knowledge chiming in.

For a little background on what I'm doing- I have a running/driving car with a EFI 408 in it right now. (I'll be using the same stand alone for the G3.) I've decided to move over to the G3 world and I had a 06 5.7 sitting in my garage. I've already done some hand porting on the heads and I plan to get an "off the shelf" cam for use with the stock bottom end. I'll likely put a torqstorm supercharger on it. I considered doing the eagle head swap, but didn't think the increased compression or doubled up head gaskets would be a good idea with the supercharger. Also, the ultimate end goal would be to build a larger displacement hemi in the future. I just want to get the car swapped to this platform with what I have on hand already. There's plenty of info on my car in my build thread. If you don't want to read through it, I'm not a drag racer, more of an autocrosser and street driver. I'd be more interested in a cam that makes really good mid-range torque and HP vs max HP at 7500RPM.

Here's a couple "supercharger" cams I've looked at:

Texas speed
223/232 @.050, .582/.582, 115+3 (appears to be only a touch larger than a stock 6.4 cam)
226/235 @.050", .582/.582, 117+4

Comp
221/233 @ .050", .594/.594 116 (very similar to the TSP cam)
229/241 @ .050", .635/.635, 117

As you mentioned above, I don't know why TSP is limiting the lift on their cams. While the large Comp cam seems very healthy, I just wonder if that duration will kill low end torque. Any thoughts on this? Given I have a smaller valve and the lowly early head, wouldn't the increased lift be beneficial?

I'm in a similar situation. I'm building a 15' BGE with Apache heads and a Kenne Bell. TSP is porting my heads but I've been struggling to find a cam to work with my application. I called MMX and they can grind me one, but I'd have to bring my own specs. Being relatively green with the G3, I don't trust myself to do that yet.

I'm interested in learning more about this
 
I'm in a similar situation. I'm building a 15' BGE with Apache heads and a Kenne Bell. TSP is porting my heads but I've been struggling to find a cam to work with my application. I called MMX and they can grind me one, but I'd have to bring my own specs. Being relatively green with the G3, I don't trust myself to do that yet.

I'm interested in learning more about this
Wow! MMX can't come up with specs?! I thought they were the hemi gurus!
 
Last year at the Indy Cylinder Head swap, I bought four 6.1 cams, low mile take outs, for 200 bucks. Score! @'63GT
I'm putting a 2014 Challenger 5.7 in my 68 keeping the VVT with TTI headers. My intent was to get it running in the car and worry about mods later.

I was just going to replace the lifters, install MDS plugs and call it good. But my gearhead son shamed me into a cam swap while it's on the stand so I just bought a new Mopar 6.4 cam and matching springs. New cam was $237 and springs were about $260. This will work with the VVT and I want to take advantage of that. My goal is a reliable interstate cruiser with occasional fun runs. I'm not concerned with ultimate HP.

I've read flow numbers of 330 at .600 so there's room for cam improvement. It seems Chrysler was conservative because it's sold to the masses. Thanks to them there are a lot of G3's available cause they keep crashing them.

It wasn't too long ago that these were considered race cams.
 
I’m collecting 6.4 parts also and have in my notes that the 6.4 non-mds stick shift cam has a decent profile.
Mopar part # 5037379BC
Trying to find the specs…
 
Wow! MMX can't come up with specs?! I thought they were the hemi gurus!

They said that because Texas Speed uses a different CNC porting program, they cannot guarantee that their cam(s) will be optimal for my application. However, if they ported the heads, then they have recommendations. I understand their position but it just seemed kind of silly.
 
Thanks for your reply. Good to see someone with some actual knowledge chiming in.

For a little background on what I'm doing- I have a running/driving car with a EFI 408 in it right now. (I'll be using the same stand alone for the G3.) I've decided to move over to the G3 world and I had a 06 5.7 sitting in my garage. I've already done some hand porting on the heads and I plan to get an "off the shelf" cam for use with the stock bottom end. I'll likely put a torqstorm supercharger on it. I considered doing the eagle head swap, but didn't think the increased compression or doubled up head gaskets would be a good idea with the supercharger. Also, the ultimate end goal would be to build a larger displacement hemi in the future. I just want to get the car swapped to this platform with what I have on hand already. There's plenty of info on my car in my build thread. If you don't want to read through it, I'm not a drag racer, more of an autocrosser and street driver. I'd be more interested in a cam that makes really good mid-range torque and HP vs max HP at 7500RPM.

Here's a couple "supercharger" cams I've looked at:

Texas speed
223/232 @.050, .582/.582, 115+3 (appears to be only a touch larger than a stock 6.4 cam)
226/235 @.050", .582/.582, 117+4

Comp
221/233 @ .050", .594/.594 116 (very similar to the TSP cam)
229/241 @ .050", .635/.635, 117

As you mentioned above, I don't know why TSP is limiting the lift on their cams. While the large Comp cam seems very healthy, I just wonder if that duration will kill low end torque. Any thoughts on this? Given I have a smaller valve and the lowly early head, wouldn't the increased lift be beneficial?
Well, when it comes to the application of most any source of boost, the dynamics that effect a NA motor goes sailing out the passenger window. Things like tuning effects of intake manifold runner length, or even Exh primary tube length become inconsequential. Also too, the flow dynamics of port CSA (cross sectional area) of the port and it's relation to valve size, is also null-void. (so long as it's not ridiculously restrictive)
This boost, that is several atmospheres higher than what you and I breath, cancels out the NA motors ability to utilize tuning factors of port shape, size, and flow coefficient. Or the ability of Int runner length to work in concert with the headers. And also explains why there's an astronomical difference between NA cams vs boosted counterparts.
That being said, you don't have to be concerned with loss of low-end. It was 'made up for' as soon as the boost crashed the party.
Keeping it simple... the last cam in your list (.635" lift) would be the best choice. But, your torque curve and consequent peak HP with that cam will be done by 6000 rpm with boost. You could extend that range some by installing the cam 'straight-up'. Getting to 7500 rpm would require a cam much bigger... probably in the 270° @ .050 range. But then the EFI wouldn't be able to 'self - learn'.
P.S. I did explain the lack of lift in the above post..

As I stated in a earlier post, in this thread, I'm going to be testing a pre eagle head. Probably next week. (see post) I may even do a write up on my findings, like I did on the Magnum heads a few years ago. (?)

I'll be up front, I'm not a boosted sort of guy.. I spent decades honing my abilities in making HP by learning how to do it, (successfully) with natural atmosphere. I don't intend this to be a poke in the eye, but to offer a glimpse into my perspective. The reality is, if I were to add boost to any of my builds, it would be a betrayal of my long experience.
 
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Think of boost as just a multiplier of whatever the engine does NA. All the same rules apply with regards to runner length and shape, port cross section ect. Anything you do to the NA engine to increase power or efficiency will be represented the same under boost, just more of it. I suggest watching as much of Richard Holdener’s dyno testing as you can. He’s been beating this way of thinking to death on the dyno for years and makes a lot of info available.
 
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