11.5:1, 1 cylinder low on compression, TFS235s: (20 more rwhp than your cam, 10 more ftlb tq)
QXI/QXL Comp Cams Hydraulic Lobes:
249/265-114+5 Lift in 0.678 range/ great work by Martin on this one.

Change Heads and cam only:
11.5:1, TEA TFS245s:
Comp Cams SOLID ROLLER, not LOW LASH, 260/271-112+4: (700+lift) (5 less hp than your cam, 40 more ftlb) lash around 0.024-0.026

Rebuild same engine for compression issue:
13:1, TEA TFS 245s:
Cam Motion LLSR by Tick Performance(this was the worse combo of all, yet had more compression)
lash 0.0015 259/271-114+4 748/723 lift (which when degreed in about engine shop WAS NOT 4 adv, but 3 noting same comp cam above at same shop was exactly 4 deg advanced)

Just to clarify, I thought those cam specs Martin cam up with would be perfect. I am seriously questioning the TEA TFS 245s.

 

It would seem to me that all of the above combinations would have HP peaks in the 6500+ range.

Do the TFS cathedral port (or any cathedral port) heads build power that high?

Just throwin' that out as a possibility; I really know very little regarding the characteristics of the cathedral port heads.

KW

 

Why so much lift? Those heads stall around ~650.

I'd actually do less duration as well given that you have the FAST on top. When Vengeance was doing their 440 packages, I know the cams were in the 262/270 range and when they dropped down to like a 247/255 they picked up a lot more torque and didn't lose any top end power using those heads. Why? Well, they reduced the IVC quite a bit and optimized the powerband.

Kip spec'd me out a 252/260 114+3 for a 418 with those heads and a FAST 102. For an IVC of 54.5. The LLSR are about 5 degrees bigger than the HR stuff with the lash, so your cam ends up being equivalent of 254/266 HR. That puts your IVC at 57. I'd aim for 52-54 with the FAST and 4" stroke.

If you look at the other two cams... the Comp I'll assume is about 8 degrees bigger with the lash, so hot it ends up being 252/263... with an IVC of 54... good.

The original cam was 51.5 IVC... So they are more optimized for the FAST and how it's tuned.

Just my 2 cents.

 

Update:

to be fair car was dynoed in Reno, NV, higher altitude, max kpa=87 there.
brought it to track, at sea level to race.

Unfortunately, snapped the rear end on launch, so no data. I could be wrong, but the engine felt like it had a lot more power than it did before.

more data to come...

Interesting thoughts above on the cam. Martin can chime in on the lift, but I think he likes airflow averaging.

 

Its not the heads nor the lift.
Keep working at it.

 

I'm going to make a few passes on the combo, then post up. I don't care where the heads peak, if they don't make power you are going to read about it.

 

Kip, I would appreciate any explanation of the exact differences between the SR and the LLSR. I did not order a LLSR, and now that I have one I would like to know. I ordered the cam from Martin, and while I trust his judgement, I have a problem now I need to evaluate, less performance than expected from my engine. Its either the CAM or the HEADS, or BOTH, as the intake has seen 20+ more rwhp with other combos.

Be as detailed as possible especially with regard to how static compression is affected.

 

My TEA 245s on my 416 show just under 680hp going down the track in just under 6000ft of d/a.
Dyno corrected at just under 800 at sea level.
I put a Racepack in car end of last year , and converter falls back almost 1600 rpm at the shift , and shows afr is rich still .
So there is more left in it .
Not sure how u can blame the heads ????????

 

you combo certainly contradicts the heads as the problem. please feel free to send any recommendations you might have w/regard to camshafts. any info you send will be kept private indefinitely. I have to evaluate everything I can find at this point.

LOL, was outside measure hood clearance.

 

While you are waiting to speak with Kip, I would like to address a bit of this.

The compression relationship:
Static compression ratio is a fixed number. It is not affected by the camshaft. If you are referring to the dynamic compression cacluation, that is affected by valve timing, but I personally do not put too much stock in the popular dynamic compression ratio calculation because it does not factor in volumetric efficiency. Obviously there is a relationship between compression and camshaft selction, but I like to talk about it in terms of cylinder pressure which I will come back to.

Hydraulic VS low lash VS standard lash solid lifter cams:
Understanding how the your first hydraulic camshaft is different VS your first standard lash solid VS your current low lash solid is all about the lobes initial ramp design. To know how they compare valve event wise just takes a little math.

The hydraulic camshaft has a lobe that is designed to start opening the valve right from "0" lash. The Low Lash camshaft lobes have an initial ramp that is designed to start opening the valves after its lash has been "taken up" by the initial lobe ramp. This is also true of the standard lash solid roller cam. A typical Low Lash might not start to move the valve until after .010" lash has been taken up where a standard lash camshaft quite often may need to take up .022"-.030" lash in the valve train before the it actuates the valves. If the camshaft lobe designer chooses, he can make all 3 of these different designs deliver the EXACT same valve action. So, in itself, the type of camshaft design does not neccessariy impart any particular difference in valve actuation.

In application, the standard lash camshaft can be useful for engines that have a large amount of expansion in the block and heads where a low lash design is just not possible or in certain racing applications where you want a very aggressive lobe. The additional lash allows for a lobe with a very fast inital lobe ramp (referred to as minor intensity). However, for most applications, all that additional lash is just not neccessary, therefor modern camshaft design can eliminate the extra lash.

So, in summary, the difference in lash in your camshaft design does not neccessariy impart any different performance characteristic in your running engine at all other than quieter operation. With that known, you can remove the Low Lash camshaft lobe design as part of your performance concern formula.

 

What was your cranking compression with your old cam and now your new one?

So, are you asserting that all of Kips cams have exactly the same valve actions? HR, LLSR, and SR?

If not, which cam would bleed off less compression? HR, LLSR, or SR, given the 0.050 are the same with lash taken up?

 

If i remember correctly the guy above me w the big black tugboat ran pretty hard with some little Cath port heads. I think ive seen them someplace before
Hahahaha

 

In comparing the 3 camshafts that you have used, you will want to look at them in terms of valve events. In order to do that accurately based on the standard duration @ .050" specification that are popular, you have to know how to adjust the solid lifter cam specs based on duration at the valve. Since you do not have a computer program to calculate this for you, I will give you a general rule that I use. That rule is that for every 2 thousandths of lash, you can figure 1 less degree of duration to equal the equivalent duration of a hydralic camshaft. I have a term that I use for this: "net duration".

So, for example, if a solid roller cam that has .010" of lash and has an intake duration of 250 @ .050", It will have the same duration at the valve as a hydraulic camshaft of 245 degrees of duration @ .050". If you have a solid roller camshaft with a lash of .024" it will have the same duration as a hydraulic roller camshaft of 238 degrees at .050", or 238 degrees net duration at .050".

So, lets compare the valve events of your 3 camshafts:

249/265 114+5 .678"
IVO: 15.5
IVC: 53.5
EVO: 71.5
EVC: 13.5
Overlap: 29 degrees

260/271 112+4 .700" .024"/.026" lash (Net duration 248/258)
IVO: 16
IVC: 52
EVO: 65
EVC: 13
Overlap: 29 degrees

259/271 114+4 .748" .015" lash (Net duration 252/264)
IVO: 16
IVC: 56
EVO: 70
EVC: 14
Overlap: 30 degrees

As you can see, from a valve timing at .050" perspective, these camshafts are all very similar. The most noteworthy difference between all 3 would be the IVC on the last camshaft that Martin spec'd for you is 3-4 degrees later than the previous two. I would assume that Martin did this to capitalize on your additional compression.

So, to go back to your original question of how these 3 camshaft correlate to your increased compression, more compression means more cylinder pressure. In general more cylinder pressure without detonation means more power. A later IVC will reduce cylinder pressure at and below torque peak. If the IVC is chosen correctly for your combination in will increase cylinder pressure above torque peak where volumtric efficieny starts to drop, thus improving high RPM power.

 

so you pulled a 147mph at altitude on the engine? is that correct?

 

I did not do a before and after test. I know that a camshafts affect on cranking compression does not neccessarily have any correlation to the power it will make in its intended operating range at RPM.

No. Not at all. My assertion is that the 3 different designs does not dictate minor or major intensity.(lobe ramp accelleration rates). So, just the fact that your current cam is a low lash, does not in itself imply any particular minor intesity characteristics. They can be made any way you want.

As my answer above points out, this cannot be implied. To complication this a bit more, you need to know that many cam resellers ask for special proprietary lobe designs. So, the camshaft that you have may have lobes that were made to Martin's specifications. This is quite common.

 

Don't forget the lobe style between those events.

 

Do you have dyno graphs to post?

 

Your contributions are appreciated. Just trying to point out those events might be similar, but those cams are not. I have not used CM before and I am skeptical at this point of both the cam and heads.

More testing to come...

 

Well, just going by what you said how you lost 25 horsepower going to the TFS245 and a Comp Cams solid roller, I would be looking at the heads or anything that might have been changed or happened during the build or tune. I would look at everything. But, I have watched you on here, I know you will keep working until you find it.

 

Yupp. Best air its ever seen is in sig. Would love to take it to Houston in February.
Its gone 144 in over 9000ft!!!