Whiplash cam on the dyno

[Babyblue66]

Here's my 77 440. It's a well used highway patrol car engine I've ran hard for years. I tore it down this winter, ball honed it, new rings, new cam bearings, I reused the main and rod bearings, since I replaced them many years ago when I spun a rod bearing, they still looked good. I put in a set of cheap replacement Elgin valves and ported the heads. I also did a valve job using a Serdi and installed viton seals. Set up the performance springs I had and used stock rockers and shafts. I topped it off with an old Edelbrock Ch4b with a 3310 750 vacuum holley. The cam I used is the smaller Whiplash SMC2942BL. It calculated out to an actual 7.45 to 1 compression with a 20 thou steel head gasket.
To my surprise this boat anchor cranked out 415 hp and a best of 465 ft lbs! Honestly I was shocked, but very happy with the outcome. I'm not quite sure what the dip in the torque graph is from. The dyno guy said it has to do with the load on the dyno before the pull starts. Although when he tied the secondary to open manually you can see a 10 ft lb increase lower in the pull.

 

[67charger383]

Great numbers for 7.5-1 compression

 

[69 GTX]

How smooth was the idle, and what was the vacuum at idle?

 

[1 Wild R/T]

Stout for 7.5-1...

 

[Babyblue66]

How smooth was the idle, and what was the vacuum at idle?

It definitely has some lope. My distributor is at 20 degrees initial so it wasn't too bad actually. I wasn't really concerned with the idle. I honestly didn't look to see idle vacuum since I have manual brakes. I'll check it when it's in the car.

 

[padam]

I've never had an engine on a dyno, so I have a question that might seem dumb.

If your peak HP is at 5200, will the engine continue to pull (or the car accelerate I guess)?
Is that rpm the recommended shift point?

 

[Babyblue66]

I've never had an engine on a dyno, so I have a question that might seem dumb.

If your peak HP is at 5200, will the engine continue to pull (or the car accelerate I guess)?
Is that rpm the recommended shift point?

Yes it will pull past that until the power falls off. Usually can shift a couple hundred rpm past it. I don't drag race so I'm no expert on shift points. I just shift when it feels right.

 

[Roger63]

Yes it will pull past that until the power falls off. Usually can shift a couple hundred rpm past it. I don't drag race so I'm no expert on shift points. I just shift when it feels right.

Did you use the whiplash recommended distributor?

 

[Babyblue66]

Did you use the whiplash recommended distributor?

I curved my old mopar performance distributor.

 

[Roger63]

I curved my old mopar performance distributor.

Did you get the specs from Hughes? Just curious as I am contemplating a whiplash cam for my 440 I'm currently building.

 

[Babyblue66]

Did you get the specs from Hughes? Just curious as I am contemplating a whiplash cam for my 440 I'm currently building.

My distributor is adjustable, I put it at 20 degrees initial and best power was 38 total. I did not talk to hughes about it.

 

[Don Frelier]

My friend nearby has a similar setup with a low compression 440 with a Whiplash in it.
He said its' difficult to tune with the low vacuum.
Sounds pretty nasty, he's happy with it.
Have to see how the valvetrain holds up over time.

 

[Roger63]

My friend nearby has a similar setup with a low compression 440 with a Whiplash in it.
He said its' difficult to tune with the low vacuum.
Sounds pretty nasty, he's happy with it.
Have to see how the valvetrain holds up over time.

I agree they do have a choppy idle. This is the 1st example of a dyno sheet that I've seen in a low compression 440. Mine is a 73 with the original flat top pistons with 906 heads I'm guessing that compression is going to be 8.2 to1.

 

[Babyblue66]

I agree they do have a choppy idle. This is the 1st example of a dyno sheet that I've seen in a low compression 440. Mine is a 73 with the original flat top pistons with 906 heads I'm guessing that compression is going to be 8.2 to1.

You'd be lucky if it's even 8 to 1. Mine have a slight dish. If they were flat tops, sitting .150 in the hole like mine, it would be just under 8.

 

[PRHeads]

Nice numbers

 

[Roger63]

You'd be lucky if it's even 8 to 1. Mine have a slight dish. If they were flat tops, sitting .150 in the hole like mine, it would be just under 8.

I've got to get the bottom end assembled first lol waiting for crank to come back from machine shop.

 

[Babyblue66]

Got it all shiny yesterday and dropped it in today. Now the snow needs to melt.

 

[Babyblue66]

How smooth was the idle, and what was the vacuum at idle?

I started it in the car today. Very lopey idle, had about 9 to 9.5 inches of vacuum at 850. Sounds good and is very responsive. i don't have the front brakes done yet. Definitely want to take it out and see how it runs compared to before I freshened it up and the comp 270h cam I put in last spring.

 

[Nate S]

It’ll do something different than the dyno with the manifolds you know. Still a nice set of numbers and should be lots of fun.

 

[71GSSDemon]

I have a similar 440 low compression motor, the Whiplash 440 cam, but used a tunnel ram, twin 660 center squirter carbs, and fenderwell headers. I would be very interested in knowing what it makes. It pulls very hard at 3000 right to 6500 (I stopped there).