Need input on Dyno results please...

[rmchrgr]

No way does it make 600 tq.... Not gonna happen. I think those TQ numbers are WAY off.

OK, if it's not actually correct (which it may or not be) how does it get so out of whack? If the torque is off, it's all off.

Here's a sheet from my dyno session for comparison. 416", 10.3:1 flat tops, ported RHS heads, mildly ported Strip Dominator intake, essentially OOTB Proform 850, TTi step headers, solid FT w. around .6" lift with 1.6 rockers. 20 initial, 35 degrees total timing, all in around 1,800 rpm. .016" valve lash for this pull. About 95-97 octane fuel mix. Nice day. Intake likely cost me 15-20 hp over a modern piece, HV oil pump probably around 7-10 hp.

 

[yellow rose]

OK, if it's not actually correct (which it may or not be) how does it get so out of whack? If the torque is off, it's all off.

Here's a sheet from my dyno session for comparison. 416", 10.3:1 flat tops, ported RHS heads, mildly ported Strip Dominator intake, essentially OOTB Proform 850, TTi step headers, solid FT w. around .6" lift with 1.6 rockers. 20 initial, 35 degrees total timing, all in around 1,800 rpm. .016" valve lash for this pull. About 95-97 octane fuel mix. Nice day. Intake likely cost me 15-20 hp over a modern piece, HV oil pump probably around 7-10 hp.

View attachment 1715120436

Looking at BSFC numbers that thing was rich rich rich. I don't know what intake you would have used, but I doubt you would have made any more power with something else. In fact, my bet is you'd have lost power.

 

[rmchrgr]

Looking at BSFC numbers that thing was rich rich rich. I don't know what intake you would have used, but I doubt you would have made any more power with something else. In fact, my bet is you'd have lost power.

Yes, I realize that. That's why I asked the OP for his BSFC #s to see if they are way out of wack.

The Strip Dom on my 416 has a slightly shorter runner and smaller plenum than modern intakes, probably better suited for a regular 340? Good for port velocity but probably not enough runner volume for the stroker. Tht's the trade off I guess. I essentially gasket matched it up into the runners like 4-5" and just did a little clean up of some rough areas in the plenum but I didn't do any blending up there.

I think one run after this, we went two sizes leaner on the jets and it didn't really do much. There was no real visible increase in power, just a different A/F ratio, like 13.1. We didn't futz with air bleeds or anything so there may be some power in those areas.

I feel like my cam timing might be a little off, like 1 degree retarded. I dunno.

Frankly, I was a little disappointed it didn't crack 525.

 

[yellow rose]

Yes, I realize that. That's why I asked the OP for his BSFC #s to see if they are way out of wack.

The Strip Dom on my 416 has a slightly shorter runner and smaller plenum than modern intakes, probably better suited for a regular 340? Good for port velocity but probably not enough runner volume for the stroker. Tht's the trade off I guess. I essentially gasket matched it up into the runners like 4-5" and just did a little clean up of some rough areas in the plenum but I didn't do any blending up there.

I think one run after this, we went two sizes leaner on the jets and it didn't really do much. There was no real visible increase in power, just a different A/F ratio, like 13.1. We didn't futz with air bleeds or anything so there may be some power in those areas.

I feel like my cam timing might be a little off, like 1 degree retarded. I dunno.

Frankly, I was a little disappointed it didn't crack 525.

I agree that you probably don't have enough cross section and plenum volume. When you get that many inches it really doesn't matter what you start with you have to weld them up to get what you want.


I have about 4 hours of welding on my SD and I probably should have don't another 10 plus the required grinding.

When I do the W-2 heads I'll have 10-12 hours of welding on that intake.

 

[mopowers]

Just another happy dyno from an engine builder who makes money selling big dyno numbers. $.02

Get it out to the track and see what it really does.

 

[NC Engine Builder]

Big HP numbers sell engines, PERIOD. Sometimes it's a calibration issue, sometimes it's purposely inflated...FABO was once a sanctuary site for the most obviously exaggerated dyno figures I personally ever saw. But that particular builder is out of business. Like has been mentioned, run it at the track and look at MPH and weight....

 

[crackedback]

Looking at BSFC numbers that thing was rich rich rich. I don't know what intake you would have used, but I doubt you would have made any more power with something else. In fact, my bet is you'd have lost power.

Agreed if the BSFC are correct. There is probably another 20 hp in jetting alone. Just a guess, sounds similar to another engine I've seen. Made 522hp and 518 tq.

Dynos are tuning tools for the most part. Taking anything from any dyno if they haven't been proven at the track is folly. I know one and trust the numbers off it because the cars run the MPH they should at the track. I have been educated by some that it takes 550+ hp to run 11.00 in a 3300 pound car... LOL It better run mid tens/mph around here or it's not close to making those numbers.

 

[273]

600 lbs-ft @ 3800 = 434 hp
500 hp @ 4600 = 570 lbs-ft
500 hp @ 5500 = 477 lbs-ft

 

[cpearce]

For what it is worth my W2 head 408 made 562 ft lbs. .580 lift hydraulic roller, single plane Victor. My heads flow close to 300cfm. On other pull with different tuning hp was 551.

 

[crackedback]

For what it is worth my W2 head 408 made 562 ft lbs. .580 lift hydraulic roller, single plane Victor. My heads flow close to 300cfm. On other pull with different tuning hp was 551.View attachment 1715120469

Put it on the track... it better run close to 129-130 depending on weight.

 

[cpearce]

Put it on the track... it better run close to 129-130 depending on weight.

Have every intent to do just that once season arrives. It is fairly white and cold here right now. Lol. Just got car running in September after a 3 year build.

 

[moper]

The results in the car will be very different. At that point you'll have the serp system as parasitic draw and the full exhaust and air filter system on it. NO way that engine's making 600 pound feet. I think it might be a little happy even at 500hp, but again - no water pump, no power steering or alternator draw, no air filter, and no full exhaust. I'd expect ETs that indicate 440-460hp at the crank.
BTW - it only matters if the engine can get the results you want IN YOUR CAR. Don't race dyno numbers. Don't accept them as god's truth. Don't send the builder 50 questions doubting his efforts before you have any real proof of output.

 

[rmchrgr]

There is probably another 20 hp in jetting alone.

Might be a little optimistic on that Rob but point taken. Frankly I didn't know much when I went in but learned a lot since then and will be better prepared next time. Again, we didn't do much in the way of tuning that day. I guess we could have sat there all afternoon trying to wring an extra 20 horse out of it but to what end? I was happy it ran close to what I expected, didn't leak or blow up. Even surprised the dyno guy, he laughed when I told hm it would make 500-525 hp.

Plus, you can't really drive it on the street if it's on the edge of detonation so it's actually a pretty true picture of what you have under normal conditions. It's always better to be on the rich side, even if it costs a little power. I will tune it in the car, (if I ever finish the damn thing) will probably look totally different under a load.

If we are still discussing my 416, I really believe there is something in the cam timing that is holding it back. When I degreed it, I couldn't get it precisely where I wanted it, even after several attempts. I called Comp, told them I was about 1/2-1 degree off they said run it. The tech told me within 1 degree + or - is 'not noticeable' and 'perfectly acceptable' but I'm not sure I buy that 100%. BTW, these are Brian's CNC heads and his cam. He suggested I could even run an LD340 and make good power. I showed him the sheets, he thought a Victor would be worth maybe 20hp. Is what it is.

Dynos are tuning tools for the most part. Taking anything from any dyno if they haven't been proven at the track is folly.

Agreed, the track will always show the truest results. And depending on the weather might not even be the same from meet to meet. However, the dyno will at least give you a base line so if the tune is way off, you will have an easier time getting back on course as opposed to trial and error.

 

[IQ52]

Never say never or impossible. They've said it about us. The cam specs will be interesting, as it sounds like there is no cam in there at all. The dyno sheet shows the same thing.

 

[NC Engine Builder]

I tried to search and find that MRL built pro comp headed small block for a example, it was was claimed to be the highest HP sbm at the time at 670 "dyno" horsepower. Later it was installed in a full race only 2900 lb A body, where after tuning it ran 122 MPH in the 1/4....the build thread seems to be gone from the site, but lesson to be learned, is dyno numbers are almost worthless

 

[RAMM]

Watched the video and I have to say-the guy in the video does a pretty good job @ covering what the build was about and even some install pitfalls. I wish we could know cam specs and such but that engine looks good, sounds good and probably makes every bit of 500 ft/lbs and maybe even 500 hp. To think that engine can achieve 1.47 ft/lb/ci is folly-but that is neither here nor there in my mind. Looks like they really accommodate the end user with video and pictures along the way. J.Rob

 

[gregsdart]

No way does it make 600 tq.... Not gonna happen.

OOTB edelbrock heads? Cam specs? Those two would go a long way towards a better number for HP/TQ.

If it's makes 500hp and 500tq... be happy and move on. I think those TQ numbers are WAY off.

Put it in the car and run it at a track. 1/4 MPH will tell you what is going on for power.

Here is something to compare your to. This one has a BUNCH more steam in it and only got to 541tq!
How To Build A Pump-Gas 620hp Small-Block Mopar - Car Craft Magazine

My 408 with mildly worked EQ heads, hydraulic roller, airgap intake pump gas motor made 517 tq at 4600, 504 up at 5700.
The dyno I used has a reputation of being honest, with performances to back up numbers.