low HP

[StangYellow]

Just had my 445 dyno'd and the results are less than I expected. 10:1 445, Edelbrock "Stage X" heads, Shelby brand intake (Performer RPM), Duraspark distributor, .045 plugs, .558int/.555ex 236/240 @ .050 108 lsa (hydraulic roller), Harland Sharp rockers, 6AL box. Ended up with a 351esque 420hp and 470tq. I guess there is some work to be sorted out as far as timing, but needless to say, I am searching for an answer as to why its so low. I am going to assume that the cam is to blame here. I didn't want undriveable, but I also didn't want this end result. Suggestions?

[blykins]

The cam is perfectly fine. 

Can you post the dyno sheets and info?  Were those corrected numbers or uncorrected?  Where was the timing?

[StangYellow]

Dyno was done today, and engine is still there. I do not have the graph, and can gather timing information at a later date. Brent, with the cam in there now, what ballpark should this be in?

[blykins]

Should make right at or very close to 500 hp. 

Post the sheets when you can.  Did they check the oil filter?

How extensive of a dyno session was it?  Did they tune the carb?  Try different timing settings?

[StangYellow]

Engine first started today, so this wasn't an extensive dyno. It is still being sorted out. The carb is a Holley 750dp. Not sure about the oil filter. I chose non-breather pentroof valve covers and a breather sticking up off the back of the Shelby intake provision. I do know the top end was flooded with oil. Possibly inhibiting the rockers? Maybe I'm missing an oil plug in the head? Plugs are Autolite XP's.

[blykins]

You just have one breather? 

If it's still being tuned, then don't get too flustered yet.  It does look low, but the carb could be off, timing could be off, and the dyno could even be extra stingy...

How high are they pulling it? 

[Barry_R]

Torque is only off by +/-30 pounds.
Horsepower looks way low.

Need some data to see what's going on.  What RPM is the peak torque at?  Normally you expect to see +-/1500 RPM between peak torque and peak horsepower.  They mathematically cross at 5250 RPM.  Sounds like you are not getting there at all yet.

[StangYellow]

Engine was run all morning today, and the timing and jetting made no difference. Still stuck around 420.  Builder disassembled the top end and measured the cam lobes. I guess the intake lobe wasn't anywhere near what was on the cam card I was given. I do not know how to measure "at .200" but I'm told it was either ground wrong, or ordered incorrectly all together. Builder said either way, that this was the issue and ordered up another ground cam to ensure it reached my target of 500/500. It's been bumped up to .650 244/248 @.050 111LSA.

With that said, my frustrations are now gone knowing that the issue has been found, and resolved by the builder. Very glad to see it resolved rather than "here you go, it's done". Thanks to those who replied. I'll give final numbers in a few weeks when its back up on the dyno.

[cjshaker]

Just my opinion, but the builder should have verified the cam specs when it was assembled the first time. Who is the cam maker?

[427Fastback]

Just my opinion but the cam that's installed should get you close to the target..I suspect there is something a miss here...Changing the cam will not find the problem..
Post the sheets and let the dyno guys have a look....Unless the cam is installed wrong I suspect the problem is external.(parts,tuning)....JMO

[blykins]

Cam was not the problem.....

Duration at .200" lift is an indicator of how aggressive the lobe is.   If the .200" numbers were not as ground, then why did he add 8 degrees more lift at .050" and another .100" of lift??  Is he changing valve springs too?

Something just ain't right here.  Can you post the sheets?  Filter been checked yet?

[Barry_R]

Agree with the troops here.  Something else is wrong.  That mild cam will get you 475-500 pretty much every time.  We run something similar here almost every week at this point.  We need data.

[StangYellow]

I agree on the 475-500. The builder told me from the very beginning that is where the engine would end up. I did express that for the FExpensive amount paid, that it shouldn't be at 420. He agreed and said he selects this same exact cam for most of his stroker builds. Maybe the 2nd grind was selected as to make sure it didn't fall short of 500 and I wouldn't complain? Either way, I am just happy this has been discovered and glad it's been remedied. I didn't receive a dyno graph as this was all done over the phone. Once the 2nd dyno run happens I will ask if there is data on the old cam.

[StangYellow]

Update to this issue. After going to the back of the line, I was recently told that FE's do NOT hit 500hp by the builder. Needless to say, I lost it and probably got pushed even further back in line. At any rate, engine is lined up to be assembled next week. I will probably bring it to another engine facility to have the engine dyno tuned. Here is the thing, the cam specs have changed from the original.... I now have .659int .666exh  241/245 @ .050 111LSA. Again, Stage-X heads from survival, hyd roller, 750dp Holley 6al, Duraspark/MSD internals, 9.8:1 compression. What would you suggest for a ballpark figure once this hits the dyno?

[Joe-JDC]

Even with 9.8 compression, you should be 535hp with those heads and .650" lift.  1.2/hp/cubic inch give you 534 hp or so.  Did you have they do any type of gasket match to the intake manifold?  There is quite a bit of airflow to be gained by a simple gasket match on the RPM style intake.  Joe-JDC