B303 Cam Question

2002BLGT · Dec 19, 2004

for those of you that have a B cam and no bottom end , this is what got mine back .....friend and old school 5.0 guy told me to have the timing to about 36-40 degrees advanced at 3000 rpm , so I did this , put it at 38 which comes out to 19 degrees initial still no pinging , might take even more timing but im happy where its at , hooked up my wideband and I guess because of the 24 lbs injectors im running had to back the fuel pressure down almost to the end of its adjustment about 30 psi , air/fuel was still 12.9 to rev limiter ..... car runs ALOT stronger , feels the same as stock off idle now .........

Michael Yount · Dec 19, 2004

The B has a 112 LSA; the E has a TIGHTER LSA at 110.

The FRPP crate motors with the X heads came with both the B (345 rated HP) and the E (340 rated HP) cams. The E cam is exactly the same as Crane's PowerMax 2040 camshaft -- Ford Racing wanted an emissions legal camshaft to sell in their line of products. Neither camshaft is designed to work with a basically stock engine - doing so usually results in unhappy customers. The bottom end torque production is significantly compromised usually for little top end performance - especially with stock valve springs which often float with either cam.

tmoss · Dec 19, 2004

Thanks Mike, I did find out the B was a 112* lobe cam, but still like to know if they have any advance ground into them.

Michael Yount · Dec 19, 2004

"Advance" ground in compared to what?

tmoss · Dec 19, 2004

For example, Comp Cams will grind a 112* lobe cam with the ICL at 108* - 4* advanced compared to the spec off 112*.

Does Ford grind the B cam at 112* ICL or someother ICL?

Michael Yount · Dec 19, 2004

"For example, Comp Cams will grind a 112* lobe cam with the ICL at 108* - 4* advanced compared to the spec off 112*." Tom - I still don't understand. Try again with different words if you can. I maintain that the whole '4 degrees advance ground in' is completely arbitrary because there isn't a common reference point for all cams to point back to.

Here's an example to illustrate the point. The cam card calls for the E303 to be installed with intake opening .050" at 0 degrees - right at TDC. I can see them offering an E with 'ground with 4 degrees advance' such that if you put that cam in 'dot to dot' (and all was perfect) and then measured it, it would show .050" lift on the intake at 4 degrees BTDC. The problem is that it's rare that all components are perfect - consequently you're gonna have to degree it to be sure that the intake is opening when you want it to. So regardless of how much advance or retard was 'ground in', you still may have to advance or retard it to achieve the proper install. You see what I mean? When it can't be tied back to something that's unchanging, saying any amount of advance is 'ground in' is an arbitrary statement.

Besides - where the intake centerline ends up is a function of installation; LSA is ground in and can't be changed - so I'm not seeing the relationship between the two.

tmoss · Dec 19, 2004

Yeah, it all relates to the spec'd ICLs of different cams, not to do with lobe centers which is fixed.

90Notch · Dec 19, 2004

B303 has 5 degrees advance ground into it and E303 has none. E303 installed dot to dot should be in on a 110ICL with a 110LSA. B303 installed dot to dot should be at 107ICL with a 112LSA.

"The B cam is more agressive, even with less lift. It has more durration and a lower lobe seperation, 107 intake 117 exaust, both considered 112."

E has a more aggresive lobe than the B303, think about in 220 degrees it goes from zero to .498" (w/1.6) where the B goes from zero to .480 in 224 duration.

90mustangGT · Dec 19, 2004

90Notch said:
B303 has 5 degrees advance ground into it and E303 has none. E303 installed dot to dot should be in on a 110ICL with a 110LSA. B303 installed dot to dot should be at 107ICL with a 112LSA.

"The B cam is more agressive, even with less lift. It has more durration and a lower lobe seperation, 107 intake 117 exaust, both considered 112."

E has a more aggresive lobe than the B303, think about in 220 degrees it goes from zero to .498" (w/1.6) where the B goes from zero to .480 in 224 duration.

No, it has a more agressive ramp rate, but has less durration. On 1.7's it has .12 more lift. Not alot either way, but the B is more agressive. Thanks for the degreeing info.

90Notch · Dec 19, 2004

"No, it has a more agressive ramp rate, but has less durration."

Yes, meaning the E303 has a more agressive lobe profile. It sound as though you define an agressive cam as one that has most duration.

"but the B is more agressive. Thanks for the degreeing info."

You are one of the few people that describe the B303 as an agressive cam. My idea of an agressive cam is one that has a lobe like this:

273(0.006") 224 (0.05") .556"

Michael Yount · Dec 19, 2004

The E is 282 @ .006"; 220 @ .050"
The B is 284@ .006"; 224 @ .050"

It's the B that has a slightly more aggressive ramp rate - it has 4 degrees more .050" duration with only 2 degrees more .006" duration.

My custom has 259/265 duration at .006" - 210/216 at .050". Fairly steep ramp.

tmoss · Dec 19, 2004

90Notch said:
B303 has 5 degrees advance ground into it and E303 has none. E303 installed dot to dot should be in on a 110ICL with a 110LSA. B303 installed dot to dot should be at 107ICL with a 112LSA.

That's what I was asking about. I thought I remebered all alphabet cams were ground "straight up" but I was wrong.

tjm73 · Dec 19, 2004

90Notch said:
B303 has 5 degrees advance ground into it....

What's your source on this, because I don't think that's correct.

Michael Yount · Dec 19, 2004

I think his 'source' is 112-107. I know the LSA is correct. Anyone know the valve timing for intake open at .050" for the B (cam card needed)? That'd let us confirm the 107.

tjm73 · Dec 19, 2004

90Notch said:
.....

E has a more aggresive lobe than the B303, think about in 220 degrees it goes from zero to .498" (w/1.6) where the B goes from zero to .480 in 224 duration.

Those duration numbers indicate how long the valve is open. Not how fast they reach peak lift. Peak lift and duration have almost no physical relationship. There is a small relationship.

What that information really tells you is the B303 is open longer at a slightly lower peak lift (224 degrees - B303 - v. 220 degrees - E303 - of rotation). The E303 opens higher (.498" v. .480"), but isn't open as long. The E303 most likely does have a higher ramp rate for opening the valves since it is opening the valve higher.

When the valves open and when they close, as well as the lobe centers they are ground on, dictate which cam is more "aggressive". The B303 allows more air and fuel to enter the combustion chamber, which in turn creates a higher cylinder pressure upon the ignition of the air/fuel mixture, which ultimately delivers more power to the crank. The B303 also has move overlap where the intake and exhaust valves are both open. To a point, this makes more power, but hurts emissions. This is why the B303 is not emissions legal and the E303 is.

tjm73 · Dec 19, 2004

Michael Yount said:
I think his 'source' is 112-107. I know the LSA is correct. Anyone know the valve timing for intake open at .050" for the B (cam card needed)? That'd let us confirm the 107.

The .050" cam specs (per FRPP website) for the B303 are as follows....

Intake:
Open 5 degrees before TDC
Close 39 degrees after BDC

Exhaust:
Open 49 degrees before BDC
Close 5 degrees before TDC

Intake duration: 107
Exhaust duration: 117

For comparison here's the E303 .050" cam specs (per FRPP website)....

Intake:
Open 0 degrees before TDC
Close 40 degrees after BDC

Exhaust:
Open 40 degrees before BDC
Close 0 degrees before TDC

Intake duration: 110
Exhaust duration: 110

tmoss · Dec 19, 2004

Mike, I didn't have time before but now I have a few more minutes. The B cam is spec'd out as a 112* lobe center cam. If ground "straight up", the intake and exhaust lobes would have that common center line. With 5 degrees advance ground into the cam, the B has a 107* ICL and a 117* ECL.

tjm73 · Dec 19, 2004

tmoss said:
Mike, I didn't have time before but now I have a few more minutes. The B cam is spec'd out as a 112* lobe center cam. If ground "straight up", the intake and exhaust lobes would have that common center line. With 5 degrees advance ground into the cam, the B has a 107* ICL and a 117* ECL.

Ahhh.......mmmmmmmm....ok...now that logic I can follow and I see that you are correct.

90Notch · Dec 19, 2004

"What's your source on this, because I don't think that's correct. "

The cam card that came with the B303 I purchased, give me a way to post and I'd be happy to share. The above posted 0.05" are also as they read on this same cam card.

"What that information really tells you is the B303 is open longer at a slightly lower peak lift (224 degrees - B303 - v. 220 degrees - E303 - of rotation). The E303 opens higher (.498" v. .480"), but isn't open as long. The E303 most likely does have a higher ramp rate for opening the valves since it is opening the valve higher."

Exactly correct! The B has 112 degrees to lift vlv from 0" to 0.480" where the E has 110 degrees to raise vlv from 0" to .498". This will always be a more aggressive lobe.

"The B303 also has move overlap where the intake and exhaust valves are both open."

Using the 0.05" durations they both have zero overlap.

tmoss · Dec 19, 2004

tjm73 said:
The .050" cam specs (per FRPP website) for the B303 are as follows....

Intake:
Open 5 degrees before TDC
Close 39 degrees after BDC
Exhaust:
Open 49 degrees before BDC
Close 5 degrees before TDC

Intake lobe center: 107
Exhaust lobe center: 117

For comparison here's the E303 .050" cam specs (per FRPP website)....

Intake:
Open 0 degrees before TDC
Close 40 degrees after BDC
Exhaust:
Open 40 degrees before BDC
Close 0 degrees before TDC

Intake lobe center: 110
Exhaust lobe center: 110

Verified on my excel spreadsheet - which is never wrong

B303 Cam Question

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