414 Dyno results: Missed combo?

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RAMM

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Before I get to the missed combo question, some specs:

360 circa '84 .060" zero deck, main studs
Scat 4" 9000 internal bal (2 slugs)
Scat 6.123 I-beams
Mahle forged -18cc dish 10.3 comp
OEM rear sump truck pan
Crane cam--sub .500"
EQ heads ported 2.08/1.60 300 cfm @ .600"+
Comp beehive /tool steel retainers
T&D 1.5 shaft rockers
Eddy RPM Air-gap quick port match
Holley 750 XP
Hedman 1 5/8" x 3" truck headers

If I've missed anything let me know.

This is the best result so far with a few pulls. 1/2" open spacer, and 30-31 total timing.

I thought it would have done better to be honest. Sharing even less than stellar results is important I think. Wish more people would.

All testing done with Esso 91 winter blend I'm sure.

What I'm hoping to spur on is a good conversation concerning camshaft choice and induction. I will provide the cam card and idle vacuum a little later. J.Rob

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That is a lot of torque, but looking at horsepower it noses over very early at 4700-ish. The last 1000rpm is hardly an increase. Not normal since it has very decent heads.
 
In for conversation and insight.

Thanks for sharing. Agreed that posting non stellar results are just as important.

Did you test with a bigger carb? Could be the culprit.
 
IMO, you are about .100 short on lift, and the headers are too small.

That's why VE is up at low RPM and then falls.

That's what I'm seeing at a quick glance.

Also, maybe the IVC is early for the displacement.




Edit: wanted to mention the BSFC looks pretty good thought the pull so the tune up was pretty spiffy.
 
HP was still climbing and 484hp/544tq is no slouch. I am impressed.

Small cam and ultra conservative timing too. You might have a little more on the table with a timing change.
 
Seems like a well tune engine to me.
I'd like to see a pull with a smaller carb, maybe a 650, then bigger headers on another.
Laugh if you want but I'd be interested in what it does for torque numbers.
 
roccodart440 said:
HP was still climbing and 484hp/544tq is no slouch. I am impressed.

Small cam and ultra conservative timing too. You might have a little more on the table with a timing change.
Click to expand...


It gained exactly 2.3 HP from 5000-5700 and only 9.8 HP from 4700-5700 RPM so I wouldn't say it was still climbing.

He only posted lift numbers. Maybe Ramm is doing a mind squeeze on us and it's some kind of a low lift cheater grind just to make us go off the reservation. IMO, it's way down on lift.

From my experience, that power curve will make the car run the same ET whether you shift at 5000 or 5700. I'd like to pile another 50-60ish and run it to 6500 RPM.
 
BTW, I think I asked this before, because it seems that's your dyno carb....what Venturi size is that 750? How about the throttle bores...what size? That means more to me than advertised CFM rating.
 
also, is it a hyd or solid cam? looks small and maybe some lifter stability issues. I have a nice solid flat tappet lunati 586/606 lift if you are interested!! :thumbsup:
 
very nice, you could chase some more hp but why,that torque is nasty! but if a few more pony's is your happy spot then a good single plane and larger headers jeting up the carb accordingly would be a easy step up. nice job!!
 
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longarm said:
Seems like a well tune engine to me.
I'd like to see a pull with a smaller carb, maybe a 650, then bigger headers on another.
Laugh if you want but I'd be interested in what it does for torque numbers.
Click to expand...

Any and all testing is good. If you paid for a 4 or 8 hours on a dyno you might as well do that kind of research.
 
I think the "lack of power" is sort of a slight combination of things. I think it's funny it's considered less than stellar results given you got over 100% VE. Which is considerable in itself.

The carb is a hair on the small side.
The cam is a hair on the small side.
The headers are a hair on the small side.
1.6 rockers would be nice.
Over 100 VE is great. Curious what your dynamic compression ends up being.

With you mentioning sub 500 lift cam. And your current power placement. I'm going to guess the cam is FTH in the 220 duration area? I would be curious to see a pull to say 6k rpm. I know it won't make more power. Given where the max torque is. But I would be curious to see what the powerband does.

What ignition setup are you running?

In either case. That's a buttload of torque and down low. That thing would be very hard to control on street! Curious to see what cam is in there.
 
No expert but you have a stout bottom end, looks like good heads but as mentioned, Small cam, carb, exhaust. Pretty impressive numbers with your combination..
 
You mentioned a truck oil pan soooo is that the reason for the mild cam? Maybe building a mean stump pulling engine for a 4x4??
 
drop in a MP .590 cam and retest. plug everything into a shareware desktop dyno program and see the difference on that simulator, very useful tool if not being a little generous on HP ratings.
 
If you could get the higher tq numbers to start at 2800, you'd never
have to downshift with a 4:10 maybe a 3:91 gear on the street.
I'm not sure if a smaller venturie carb would speed up the airflow
and feed the cylinders more across the rpm range.
From the airflow numbers it never drew more than 600cfm and max tq
was at 512cfm.
Just a curious thought to see if was overcarbed.
 
Perfect engine for my "Towing Dakota."
Tow the race car to the track, tow what it ate off the track.... race around town with it.
 
The CFM per RPM was dropping quickly by the time it crossed 4K, not enough cam for big HP numbers, & I woulda opted for 1.6 rockers Myself at least on the intakes.
I agree w/longarm, I'd like to see a 650DP pull, and the torque curve.
 
Looks pretty good to me. I think you did exactly what you were trying to do.
 
I see the word "truck" mentioned too often...
So it goes in a 5000lbs. something?
 
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If the cam specs are typical for sub .500 lift cams, it will ping on the California 91 octane pump gas.
 
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