Cobra Jet Cams or Comp Cams????

[az20115.0]

Trying to decide on which cams to go with for heads/cams Coyote NA build.. There is plenty off info on comp stage 3 cams by now but no much on the CJ cams, except the CJ cams have higher lift and do not require VCT lock outs, which is a huge plus! Mainly I am looking for HP gain and TQ loss, or dyno sheets..
Any data or thoughts??

 

[Sean@LethalPerformance]

Subscribed, cams are next up for me after cj mani

 

[stang8psi]

Make sure you can use the cj cams with the heads. With a bigger lift there is ( on non boss heads ) material that has to be removed for clearance with the additional lift of the cams .

 

[az20115.0]

Make sure you can use the cj cams with the heads. With a bigger lift there is ( on non boss heads ) material that has to be removed for clearance with the additional lift of the cams .

I want to run Livernois stage 3
Thats should be ok I think

 

[Livernois Motorsports]

I want to run Livernois stage 3
Thats should be ok I think

Have you called in and spoke to anyone about your specific goals? If not please PM me and I would be more than happy to help guide you to the selection that is right for you! -Chris

 

[az20115.0]

Have you called in and spoke to anyone about your specific goals? If not please PM me and I would be more than happy to help guide you to the selection that is right for you! -Chris

Going through the email process right now.. I believe I'm speaking with Dave
I'll Probably call you guys soon anyway

 

[Livernois Motorsports]

Going through the email process right now.. I believe I'm speaking with Dave
I'll Probably call you guys soon anyway

Just making sure you are being taken care of! -Chris

 

[momstmg]

That would be cool to have the cj cams and stage 3 heads from livernois.

 

[Deranged2013]

I'm also interested in the CJ cams and if they work well with FI.

 

[az20115.0]

That would be cool to have the cj cams and stage 3 heads from livernois.

Yes, I just wonder how cool, horse power wise

 

[SmokeGreyHatch]

There is so much misinformation around cams. The CJ cams are worthless. The ramp rates are not aggressive by any means. Example: JDM took a N/A 2013 Cobra Jet from 430 rwhp stock (through auto) to 550 rwhp with just a valve job and custom cams. I know of another car with boss heads, boss intake and CJ cams that put down 440 rwhp through an MT82. I made 453 with a CJ intake and exhaust on pump 91.

If you're using the stock valve springs you can only get away with up to 12.5 mm of lift. Anything more may require shimming the valvetrain and/or a change to the boss head architecture, plus the obvious supporting valve spring.

Lastly, you can run Comp Stage 3 cams WITH VCT. If you mock it up it's completely clear. A reputible tuner can tune timing events to be acres away cleanrance wise. It HAS been proven, but Comp doesn't want sheep going out, not installing limiters and getting crazy with timing events. Any tuner with reputable cam timing/design and engine knowledge can tune through this. What this means with a 50 degree sweep is you CAN have stock cam low end with stage 3 top end, not crazy losses down low as a trade off for up top. Here is the combo on one of said vehicles:

Boss intake/90 mm TB/ JLT CF CAI
1 3/4 longtubes, full off road exhaust
Comp Stage 3's full VCT
Completely stock GT heads

502 rwhp on E85, 520 rwhp on FTW

If I were doing custom cams N/A, I'd start with comp Stage 3's, but 12.5mm on both and increase duration 3-4 degrees on the intake and 6-7 on the exhaust. Timing tweaked with VCT. You'd have a car with stock low end that would pull all day long to 8k.

 

[SmokeGreyHatch]

And another thing. Heads are not a cost effective mod on an N/A car. They are worth 20-25 tops and only needed if going for 600 rwhp N/A. You can make 60-90 rwhp with cams alone.

Recipe for 550 rwhp:

Custom cams
CJ intake
SCJ TB
4.5 inch CAI
1 3/4 or 1 3/4-1 7/8 step + full exhaust
E85 Fuel

Recipe for 575 rwhp:

Custom cams
CJ intake
SCJ TB
4.5 inch CAI
1 3/4 or 1 3/4-1 7/8 step + full exhaust
FTW Fuel

Recipe for 600 rwhp:

Valve job (back cut), light port on heads (stage 1-2)
Custom cams
CJ intake
SCJ TB
4.5 inch CAI
1 3/4 or 1 3/4-1 7/8 step + full exhaust
FTW Fuel

 

[az20115.0]

And another thing. Heads are not a cost effective mod on an N/A car. They are worth 20-25 tops and only needed if going for 600 rwhp N/A. You can make 60-90 rwhp with cams alone.

Recipe for 550 rwhp:

Custom cams
CJ intake
SCJ TB
4.5 inch CAI
1 3/4 or 1 3/4-1 7/8 step + full exhaust
E85 Fuel

Recipe for 575 rwhp:

Custom cams
CJ intake
SCJ TB
4.5 inch CAI
1 3/4 or 1 3/4-1 7/8 step + full exhaust
FTW Fuel

Recipe for 600 rwhp:

Valve job (back cut), light port on heads (stage 1-2)
Custom cams
CJ intake
SCJ TB
4.5 inch CAI
1 3/4 or 1 3/4-1 7/8 step + full exhaust
FTW Fuel

Finally some great advise.. Thank you, that is what I was wondering about.. Whether or not the CJ cams are aggressive enough.. I spoke to Shaun (AED) and I'm getting similar info from him.. Comp Cams it is then..
I know heads are not very cost effective, but mine is a coyote engine, and there is probabaly some room for imporvement
Any thoughts on Heads? Livernois stage 3 heads seem to be ready to go, and I know they build awesome cars.. (wanna sponsor me Livernois?) If I'm gonna do this, wanna go all the way.. Why should Corvettes have all the fun
I already have my full exhaust from JPC..

Also, I take it the single blade CJ TB is better than twin? I know it flows more, but HP wise, is it better?

Thanks again

 

[az20115.0]

If you mock it up it's completely clear.

Sorry, but what do you mean by that?

 

[SmokeGreyHatch]

Sorry, but what do you mean by that?

Piston to valve clearance

 

[SmokeGreyHatch]

Finally some great advise.. Thank you, that is what I was wondering about.. Whether or not the CJ cams are aggressive enough.. I spoke to Shaun (AED) and I'm getting similar info from him.. Comp Cams it is then..
I know heads are not very cost effective, but mine is a coyote engine, and there is probabaly some room for imporvement
Any thoughts on Heads? Livernois stage 3 heads seem to be ready to go, and I know they build awesome cars.. (wanna sponsor me Livernois?) If I'm gonna do this, wanna go all the way.. Why should Corvettes have all the fun
I already have my full exhaust from JPC..

Also, I take it the single blade CJ TB is better than twin? I know it flows more, but HP wise, is it better?

Thanks again

Take a moment and truly understand your goals. Is 25 hp worth $3k to you? Then by all means go all out. Money is better spent in other areas. Spend the 1500 on cams and get 3-4 times that. If 550 is not enough then I would seriously consider the shortblock if you're doing heads. Heads are pointless without doing the short block if you're going into the motor that far.

Look at the recent CJ intake thread I posted in. I listed the differences in airflow surface area (cross section). The mono blade blows everything out of the water. Why would you spend the same money for something inferior flow wise and drivability is not compromised. I know as I had the SCJ thorttle body with stock like drivability

 

[az20115.0]

It's very surprising to me that heads are only good for about 25hp.. I would have thought they would be good for at least 40 or so.. Stage 3 anyway.. I was planing on upgrading the rotating assembly but that's about it for the bottom end.. Maybe doing just cams is a lot more cost effective, I just thought that heads is an extremely important part of an NA build. I never thought that just cams and supporting mods are good for 550. I saw a boss make 500 with just cams and CJ intake, but nothing more
All very good info though

 

[SmokeGreyHatch]

It's very surprising to me that heads are only good for about 25hp.. I would have thought they would be good for at least 40 or so.. Stage 3 anyway.. I was planing on upgrading the rotating assembly but that's about it for the bottom end.. Maybe doing just cams is a lot more cost effective, I just thought that heads is an extremely important part of an NA build. I never thought that just cams and supporting mods are good for 550. I saw a boss make 500 with just cams and CJ intake, but nothing more
All very good info though

Don't get caught up in stages, it's marketing "bigger/better". In an N/A car you want port velocity and flow under the curve up to your cam lift. Anything after your max lift is useless. Stage 2/3 usually only pick up past .550 lift which will be pointless at 500 thou or 12.5 mm. You also make the port volume bigger reducing velocity. These heads are extremly efficient for up to 575-600 rwhp (depending on drivetrain efficiencies). No need to do anything more than a valve job and valvetrain (valves/springs, etc). It's all a snowball. If you're going to do the short block, then do oil pump gears, high compression, E85 (12.5-13:1). The problem is that no matter what, you can't get more than 8100 rpm out of these things, Copperhead limited. You have to limit your cam grind for most area under the curve through 8000. At that point SCT can't control TiVCT as well. If you want to shift at 8100, then just run more agressive cams and lockout the VCT altogether. That Boss was not impressive in the 5.0 article. With GT heads and stock cams I was only 10 off with a 4.5 CAI on FTW fuel. The best bang for the buck N/A combo would be:

custom cams
CJ Intake/SCJ TB/4.5 CAI
longtubes full exhaust
ID 725's
3.90 gears
E85/FTW fuel

Mid 10's at 130+ at 3500 lb in good air for less than $5k in mods. Keep the stock heads, valve springs, short block. If you want N/A it's all about weight reduction and efficiency. Big's/Littles, lower with relo brackets and no front sway bar, good RST/RXT clutch, aluminum D/S, and let it eat. 7k dump, 1.49 or better 60' and put a whoopin' on your blower buddies.

 

[az20115.0]

Look at the recent CJ intake thread I posted in. I listed the differences in airflow surface area (cross section). The mono blade blows everything out of the water. Why would you spend the same money for something inferior flow wise and drivability is not compromised. I know as I had the SCJ thorttle body with stock like drivability

Checked out your thread
Great stuff.. I didn't realize you're in Phoenix. I'm in Tucson.. BTW, our track is open, but I'm saddened to see you sold your set up..

I also plan to make a trip to AED like you did to dial in the car, once I finish it..
Because I'm not an expert in cam timing or lift, I probably won't venture into the territory of going for custom cams.. Comps should work ok I guess, unless Shaun recommends otherwise.. so far he told me he likes them just fine

I am now seriously thinking about skipping the heads, and making up the power else where like electric water pump or coils.. I am probably going to skip the race fuel thing.. It would be too inconvenient for me.

Anyway, thanks for the help..
If you have any parts left from that CJ combo, let me know, but I think you sold everything

 

[corysmach1]

And another thing. Heads are not a cost effective mod on an N/A car. They are worth 20-25 tops and only needed if going for 600 rwhp N/A. You can make 60-90 rwhp with cams alone.

Recipe for 550 rwhp:

Custom cams
CJ intake
SCJ TB
4.5 inch CAI
1 3/4 or 1 3/4-1 7/8 step + full exhaust
E85 Fuel

Recipe for 575 rwhp:

Custom cams
CJ intake
SCJ TB
4.5 inch CAI
1 3/4 or 1 3/4-1 7/8 step + full exhaust
FTW Fuel

Recipe for 600 rwhp:

Valve job (back cut), light port on heads (stage 1-2)
Custom cams
CJ intake
SCJ TB
4.5 inch CAI
1 3/4 or 1 3/4-1 7/8 step + full exhaust
FTW Fuel

Your the man. Your knowledge is awesome. Seriously. NA power is awesome to me and 550 rwhp would be a blast.