How to build a high revving 440?

[padam]

I’ll probably get flamed for this, but I thought I remember reading in a direct connection engine book, that balancing wasn’t that important for a drag engine.

 

[BSB67]

Been around BB Mopars for 45 years. Never seen one stop pulling at 4800. Maybe your valve springs have gone south.

 

[BSB67]

I’ll probably get flamed for this, but I thought I remember reading in a direct connection engine book, that balancing wasn’t that important for a drag engine.

A long time ago I remember reading an article where Paul Rossi, sponsored by DC, stated that he would rather run an unbalanced motor over putting weight back in to balance it. I think he was referring to his 6pack Super Stock Challenger.

 

[Dodge Bros]

800+ HP in a convertible is pretty banana’s!
But you know…it is this kind of banana’s

Pretty big difference in HP between 5 lbs of boost and 10 lbs. 5 lbs turning to 6500 probably won’t test the engine much. Would think 10lbs at 6500 is going to test everything.

What is the compression of the 528 Hemi now?

 

[Dennis H]

Been around BB Mopars for 45 years. Never seen one stop pulling at 4800. Maybe your valve springs have gone south.

But I don’t care. RWHP line started to level at 4850. Grunt. Upshift.

 

[451Mopar]

My question is at what point is it cost effective to start with an aftermarket block?
My build is the 400 "230" block with BCR aluminum main caps and 1/2" girdle, and cylinder #8 was sleeved after the back fire from breaking the rocker stands on the first set (early production run) of MW heads. The Hughes CNC ported heads are a later casting that had much longer heli-coils in the rocker stands.
The 440 source 4.15" stroker kit flat top pistons (pretty light weight for off the shelf parts).
With the Victor MW heads, compression is around 12.4:1 if I recall it correctly?
The cam uses the Comp HXL lobes, with a bit more duration than Andy F used on the Trick Flow 270 headed 3.91" stroker engine. He had a worked intake manifold and vacuum pump and was making around 750+ HP
https://www.motortrend.com/how-to/dyno-tested-vacuum-pump-help-engine-make-power/#google_vignette

 

[INTMD8]

But I don’t care. RWHP line started to level at 4850. Grunt. Upshift.

It's your car to do as you like with but if someone was trying to achieve max acceleration for a given combo they wouldn't shift exactly at peak HP rpm.

As long as the valvetrain/etc holds on and power doesn't abruptly fall off a cliff (indication of a problem) you would shift several hundred rpm after peak hp rpm to keep the engine in max average horsepower range.

The exact number can be calculated closely vs gearing then tested.

 

[19_Dart_68]

What needs to change to make a big engine spin to much higher rpms, like 6500 or so. Not looking for a build recipe, although that would be nice. What needs to change in theory? Big blocks are known for low end torque. What does it take to make it spin much higher?

Shorten the stroke, lighten the rotating assembly and solid cam w/heavy valve springs. 7500+ RPM

 

[RemCharger]

Shorten the stroke, lighten the rotating assembly and solid cam w/heavy valve springs. 7500+ RPM

Exactly. About a 3.375, with a 4.31 bore. Max wedge heads.

Oh wait, the guy wanted 6500 rpm

 

[Geoff 2]

Shorten the stroke? It is already a short stroke for a BB engine; 1/4" shorter than a 454 Chev & 1/2" shorter than a 455 Olds or Pontiac.

 

[INTMD8]

The stroke isn't going to matter. It will come down to, in this case, will the rods/pistons stay in one piece and is the valvetrain stable at that rpm.

Seems like lots of info missing.

So it's a 75 motor home 440 with stock rods/pistons? Not sure how boost is 5-10psi. So it's either 5psi or double that?

"nice springs" means?

"making a bit more boost down low, and less up top"

Centrifugal supercharger builds boost with rpm.

Only way to accomplish more boost down low and less up top is to pulley it to spin faster (will give you a bit more boost down low) and restrict the inlet (limiting high rpm boost).

 

[RemCharger]

P0st #50. Lol

Really. Never had a bb BOP stroker close to a 383.. think about that.

 

[dvw]

When I suggested Ti valves that was for high end RPM for a motor seeing that level on a regular basis. My 572 runs Ferrea stainless valves, the less exxpensive Pac 1224 springs. It sees 7100 on every pass with a 4.5" stroke. Most stock rod, heavy piston stuff seldom makes power above 6300 anyway.
Doug

 

[INTMD8]

When I suggested Ti valves that was for high end RPM for a motor seeing that level on a regular basis.

I'm running ferrea stainless as well and shifting at 7750. Only thing keeping me from experimenting with a higher shift point is not having titanium valves.

 

[dvw]

Its not that stainless won't work. It's how long. I retired mine at 750 passes.
Doug

 

[theman440]

With my old stock steel crank 440 with LY rods and forged flat-tops I'd shift at 7000 and at lower elevations and good air It would go 7200 thru the traps.

 

[BSB67]

With my old stock steel crank 440 with LY rods and forged flat-tops I'd shift at 7000 and at lower elevations and good air It would go 7200 thru the traps.

Were the slugs typical 850 gram TRW/Speed Pro pistons w/ 225 gram pins?

Thanks

 

[theman440]

Were the slugs typical 850 gram TRW/Speed Pro pistons w/ 225 gram pins?

Thanks

The pistons were custom forged Arias with .094 tapered wrist pins. I bought them in 1991 and don't remember the weights. They were virtually identical to the Custom Ross Pistons in my new 493.

 

[Chilsam]

I shift my basically stock 440 Sixpack other then camshaft at 6200-6400 ish. At 6500+ it flings one belt or another. I shift my 528 Hemi at 7600.

What cam, lifters n valve train are you using on the 440 ?

 

[65CopCar]

When I suggested Ti valves that was for high end RPM for a motor seeing that level on a regular basis.
Doug

Yeah - my 574 is good good for 8000 rpm according to Tony Bischoff (won't know how high I will spin it till I get out of transmission purgatory). You betcha it has titanium valves.

I spun my 528 to 7400 rpm. Never an issue.

6500 is not high. My old old 440 ran to 6800 rpm all day long. High 10's in a 3500 lb car. Built it in the 80's and ran it probably 20 years. Nothing special - deep oil pan, ported 906 heads, decent cam, stock rods and very heavy Arias domed pistons.