440 stroked to 499

[1969CoronetR/T]

I had my 1969 Coronet R/T 440 engine bored .040 and stroked to a 499 cid using an Eagle rotating assembly, .040 Wiseco pistons, roller camshaft (do not know brand, maybe Comp Cams) Harland Sharp roller hydraulic lifters, high volume Melling oil pump, Moroso Perm-Align valve cover gaskets, 3000 stall converter with ported Indy EZ-1 heads and port matched Indy intake. The cam is 545 lift with a 235/241 duration and 110 lobe separator / 106 centerline. The compression is 9.6 to 1 and this seems too low for a stoker. The engine builder put it on his chassis dyno and it had a peak horsepower of 585 (I have to look at the dyno sheet at home for the RPM and torque numbers). I am a little disappointed as he claimed it will easily get 650 HP with 450-500 at the wheel. I had a little 340 stroked to 416 that produced over 500 HP in a 1971 Demon that I sold a few years back. Does this sound too low of a HP gain? I think a 500 cid engine with these ported heads should easily hit over 600 HP.

 

[super-bee_ski]

Well, you certainly have the best of everything in that block.
Uh, 585 HP is nothing to sneeze about.

What size carburetor do you have?
On the Dyno did you guys "dial it in"?
(experiment and adjust timing and re-jet the Carb etc to find the correct combo?)

 

[1969CoronetR/T]

Holley 850. It blew coolant on the second run so I am assuming the numbers may be lower as he could not dial it in. He has to take the passenger side head off to see why it is leaking coolant from the rear. He thinks the head is porous and I hope it is just a head gasket failure. Strangely, it ran great for 200 miles without a problem and then I got a coolant leak from the one head. The builder put K-Seal cylinder head sealant in the radiator (pissed me off - a band-aid instead of fixing the problem correctly) and that held for a few weeks until he went to put it on the dyno. The oil is nice and dark so it is not leaking inside the engine, but I am really questioning his and the machinist capabilities. It is now siting dormant for the next few weeks until he can take the head off and pressure test if for porosity which he should have done before the build. At least I have the Super Bee to drive, but I hate to put too many miles on it.

 

[super-bee_ski]

I know what that is like
I did a Dyno run on my 70 Hemi (Relatively stock with stock Mopar "automatic cam" in engine)
We only ran my 70 Hemi up to 5,600 RPM
I had 457 HP

Hmm, Im thinking 625HP would be about right for this combo
BUT: was this an initial break-in RUN?
Perhaps the Dyno technician didn't want to run the engine up to 6,500 RPM to get the big numbers?
850 CFM carb sound correct.
Did you run headers for the Dyno run?

The guys to "talk to" on the forum are:
IQ52
LewT
Meep-Meep
Bruzilla
Mike Gaines
All the guys that know engines better than me

PS: To get that HP out of your 340 demon it must have been "way up there in RPMs"

 

[lewtot184]

sure that was a chassis dyno and not the engine dyno?

 

[1969CoronetR/T]

This was the initial break in run before the coolant decided to find a new home. I have TTI headers with a 3" exhaust and Dynomax Turbo mufflers. The little 340 stroker produced over 500 HP at 6,000 RPM give or take 500 RPM. They like to run high RPM's. I have to download a picture of the dyno sheet when I get home for my current build.

 

[super-bee_ski]

As "lew" asks,
Was this on a engine Dyno or a chassis Dyno?

1969CoronetR/T:
Was the engine in the car when you ran it on the Dyno?

 

[dieseldazzle]

Are you talking about 585hp at the tire???

 

[lewtot184]

585 at the tire is going to be around 700 at the crank. in my opinion that's probably a crank horsepower number on an engine dyno and i wouldn't complain considering the small cam and lower compression.

 

[1969CoronetR/T]

No, it was a chassis dyno and it was 585 at the engine.

- - - Updated - - -

585 at the tire is going to be around 700 at the crank. in my opinion that's probably a crank horsepower number on an engine dyno and i wouldn't complain considering the small cam and lower compression.

lewtot184,
Do I have too small of a cam? I do think the compression is too low.

- - - Updated - - -



Sorry about the delay. I had to cut the grass after work and then I went for a run with my oldest daughter. We then went out in the Super Bee for ice cream. It blew coolant just after 4600 RPM.

 

[383man]

A chassis dyno can only do rear wheel HP. This sounds like the eng itself was dyno'd and the 585 is crank HP. Because as was said if it had 585 at the wheels thats getting close to 700 crank HP and I cant see this build getting near 700 crank HP. Heck I run 10.70's at 3700 lbs with about 600 crank HP and I would guess about 525 at the wheels. The 585 crank HP sounds about right. Strokers make tons of torque which helps get heavy cars moving real quick. Ron

 

[dieseldazzle]

Don't get caught up on dyno numbers. How's the thing run? That's the question and it sounds to me like it's running like **** and you said blowing Coolant at 4600 you mean out the tail pipe???

 

[lewtot184]

i'm reading 467hp at the wheels and 573ftlb of torque at the wheels. am i missing something?

 

[Cranky]

Don't get caught up on dyno numbers. How's the thing run? That's the question and it sounds to me like it's running like **** and you said blowing Coolant at 4600 you mean out the tail pipe???

I'm with you about dyno numbers but they can be a good tuning tool. He said that it's blowing coolant out of the head or head gasket and is not sure if it's a porous head or just a gasket.....

 

[1969CoronetR/T]

I read the numbers backwards (color blind) and torque was 585. Just seems like a kick in the balls after I was told it will make easily 600 HP at the engine (crank?) and now it is considerable less after a head gasket or a cylinder head failure. Two strikes against this guy and I may be sending the engine to Bowman Performance.

 

[lewtot184]

with the torque curve that engine has i'd have to ask; why a 3000 converter? i think the power is about right for the build. 570+ftlbs at the rear wheels should be real peppy. easy mid 11's. loose converters and low gears would probably hurt the performance of that engine combo. a friend of mines 4150lb '67 charger went 11.60's-120+mph on 3,23 gears, tight converter, cast exhaust manifolds, and nearly the same power you have.

 

[1969CoronetR/T]

The builder suggested the 2800-3000 stall loose converter for the cam shaft. I had 3.91 gears in the rear end before the build and they were way too steep. I switched to a Truetrak and 3.55 gears to save the engine on the highway as it maxes out at about 55 MPH and turning 4000 RPM. Is the cam shaft too small?

 

[super-bee_ski]

Holy Hell!
585 at rear Wheels?

NICE!

(That is what "we" thought, a Chassis Dyno.)

 

[dieseldazzle]

with the torque curve that engine has i'd have to ask; why a 3000 converter? i think the power is about right for the build. 570+ftlbs at the rear wheels should be real peppy. easy mid 11's. loose converters and low gears would probably hurt the performance of that engine combo. a friend of mines 4150lb '67 charger went 11.60's-120+mph on 3,23 gears, tight converter, cast exhaust manifolds, and nearly the same power you have.

Do do you have more details on your buddies charger or just bs67 on moparts?

- - - Updated - - -

The builder suggested the 2800-3000 stall loose converter for the cam shaft. I had 3.91 gears in the rear end before the build and they were way too steep. I switched to a Truetrak and 3.55 gears to save the engine on the highway as it maxes out at about 55 MPH and turning 4000 RPM. Is the cam shaft too small?

Be careful or your gonna be on the converter most of the time

 

[1969CoronetR/T]

Ssuper-bee _ski,
I do not think I have 585 at the rear wheels, I think that is the torque.