94bamf

Ok, so I have been looking for a cam for the GTO for a while now. Found one I kinda like from Vinci High Performance.

Its called the BOSS 2, here are the specs.

DUR @ .004" 278*/286*
DUR @ .050" 216*/224*
LIFT .551/.551
OVERLAP 53*
LSA 115*

Seems like a fairly mild cam that should Idle decent.


I have been on the Crane Website checking out there lobe specs. Looks like the Vinci cam uses some fairly weak lobes compared to some of the Comp lobes. But Crane does have another set of lobes that are much more aggressive. Check this out.

Dur at .050------Adv Dur----Dur at .200-------Valve lift 1.7
HR-216/3241------278--------133--------------.551
HR-216/344-------277--------139--------------.585

HR-224/3241------286--------139--------------.551
HR-224/344-------285--------146--------------.585

The 3241 are the Vinci cam lobes. The 344 are the more aggressive lobes. Look at the difference in dur at .200, the 216(344) lobe is as big as the 224(3241) lobe.

So anyway, my Question finally.

Could I have crane make me a cam with the more aggressive 344 lobes with the same 115 deg lobe sep and maintain the same Idle and driveability of the BOSS 2 cam, yet make more HP from the added duration at .200 and the added lift?

Thanks in advance for any responses....

DAPSUPRSLO

iTrader: (14)

The 344 lobe has more advertised duration wich will add more overlap verses your boss 2 cam but this you must know as the .050" duration of the boss 2 cam is less also. More overlap will negatively impact idle and driveability but will make more power. Further, a more agressive lobe will make more power up to the point of when your valve train cannot control it. A more agessive lobe adds more duration at all lift values, hence having a larger lift curtain; however, when the valvetrain cannot control the lobe (which shouldn't be a problem with any of the cams you have listed so long as you select propert valve train components) then power will be lost through valve float.

PREDATOR-Z

Use that cam (Boss 2) with accelerated lift Crane rockers and you would achieve pretty much the same without torturing your valvetrain.

94bamf

Actually the 344 lobe has less advertised duration. If you notice both 344 lobes have 1 deg less advertised on both intake and exhaust compared to the 3241 lobe. When compared to the Comp cams XE-R lobes the 344 lobes are very much alike on paper.

Here are the specs for the Comp lobe.

273 adv duration
224 dur at .050
145 dur at .200
.581 lift with 1.7 rockers

Comp uses advertised duration at .006 while Crane uses .004 so that accounts for most the difference there. Comp doesn't make a XE-R lobe under 220 deg durration at .050...

I don't really see how overlap would be any different between either the 344 or the 3241 lobe as long as I put my cam on a 115 deg lobe sep angle, if anything maybe slightly less overlap since it has one deg less advertised on both intake and exhaust. I would even consider putting my cam on a 116 deg lobe sep unless somebody thinks that would really hurt power.

94bamf

While I would love to have the rockers,,,$669 + a $400 cam and $160 valve springs if I went the cheap way with Comp 918's is just crazy.

I would rather spend $400 for the cam, $100 for pushrods and $160 for springs.

You tell me........$1229 or $660.......

Deeavi

iTrader: (16)

I just bought that VINCI cam (#056), and I am in the process of installing it!

I had the Lunati 55006 cam, and it made good power, but bottom end power, especially with my A4 was lacking. I am hoping to pick up a lot of torque with the VINCI cam. According to VINCI High performance this cam still has a chopy idle, which is what is what I would like to keep!

PREDATOR-Z

I can tell you that $660 is a fraction of your install. Add lubes/oil, chain,oil pump, gaskets and I'm not mentionning install, or tune/dyno

94bamf

The car has 1900 miles on it right now. I won't be doing a chain or pump. I will be doing the install myself, so that will take care of the labor cost too...I also have HP tuners, so I will atleast be attempting to do the tune too.....

mrr23

iTrader: (3)

there is better benefits by going the smaller lobes with larger ratio rockers. with the larger lobes, you stand more of a chance of the lifters to 'loft' off the cam. basically meaning the lifter not even touching the cam. people think it's valve float when it really the lifter flying off the lobe. then landing on the base circle. or even when the lobe is back on the upward swing. so, smaller lobe will help to prevent this from happening. less need for higher spring seat pressures.

and if the larger ratio roackers vs larger cam lobes is such a wrong thing to do, then why did GM move from 1.5 to 1.6 when they wanted more out of the LT1 to make the LT4. then move to 1.7 with the LS1. and now 1.8 with the LS7? man what is GM thinking?

obrien24

iTrader: (2)

Give Revxtreme a call. They have several good cams out right now, and have some new ones coming out that you might like

DavidNJ

Big rockers are a good thing, mrr23. The LS1 issue is that GM made a very light valve train, which is very hard to duplicate in the aftermarket.

The big rockers not only reduce the movement of the lifter, they increase the leverage of the valve spring. Getting that advantage with the available cams is the issue.

The difference in lifter/pushrod movement is less than 10%. That is much smaller than the margin of error in these street valvetrain designs (if this was a $$$ racing effort, we would be Spintron testing everything). So the XERs or equivalent seem to be the best way to go for most.

Does anyone run the XERs with a 1.8 rocker?

mrr23

iTrader: (3)

vinci/crane gives you that advantage using their stuff. the accelerated lift/quick lift technology is very similiar to the comp XE-R lobes. it can be done. but everyone is being told they can't. i already use the rockers and the vinci/crane dual springs. cam is all that's left to do in the wife's car. TR says not to with their ramp rates and lifts. vinci/crane solved the spring issue with doing the accelerated lift/ high ratio combo.

roger has talked with me about spintron testing to some degree. and with the latest laser camera thingy they have, he's told me of pictures he's seen of the lifter 'lofting' off the cam.