Engine specs for a '78 440

by **pscartozzi** » 29 Feb 2004 5:24

Hello all,
I have recently put a 440 in my 70 Challenger. It was out of a '78 Dodge truck. I'd like to find the engine specs. I'd like cam spec's, compression, etc. I'd like to put some of it into Desktop Dyno so I can test the effects of various modifications. All of the websites I have found stop listing engine info after 73.
Thanks,
Perry

http://home.nycap.rr.com/pscartozzi/

by **dave-r** » 29 Feb 2004 18:02

You need a workshop manual for the truck it came from.

I wouldn't even bother working it out. Just remove it and fit a Hughes Engines cam. Job done and say hello to performance.

by **pscartozzi** » 02 Mar 2004 4:50

I'd love to Dave but what's the use of a hot cam with low compression and smogged heads? It will come with time. Are the Hughes cams that much better than the MP grinds?

by **dave-r** » 02 Mar 2004 8:29

Smog heads? Are you kidding? You have the best stock heads made for a 440.

The cylinder pressure is only an issue if you go wild with the cam. The bigger the cam the more cylinder pressure you need. So yeah if you want a hot motor you need to fit higher compression pistons. But Hughes do cams for everything including RV engines like yours.

I still don't see why you need to know what is in there now? Remove all the spark plugs, stick a compression gauge on, disable the ignition, open the carb wide, and crank the engine until the pressure on the gauge stops rising. Use that reading on each cylinder to see how good your piston rings and valve seats are sealing. Average that and see what the cylinder pressure requirements are for each cam on the Hughes Engines web site.

The MP cams are a bit better than they were but still have little lift for the amount of duration. Hughes cams work great. Read the explanation why on the hughes engines web site.

by **pscartozzi** » 03 Mar 2004 0:27

Dave,
Point taken. I've done that all and I feel a rebuild is in order. I just wanted to have a feel for where I was vs. where I am going. I also wanted to see if Desktop Dyno predicted anything close to the actual performance. If it does, it's a lot easier to 'buy' 10 differnet cams in one night and compare them.
I've read through the Hughes website, and yes, they explain why their cams are better. The Crane website lists why theirs are better, the MP website lists why theirs are better. I was trying to get the opinion of people who have had more experience with the different grinds/manufacturers. I'm aware of Hughes and their reputation.
Do you really feel that my 452's flow better than 906's. I have a set of each to choose from. I like the hardened seats in the 452's. My plan is to take the 452's and perform a mild porting job myself. Not having done this before I was planning on using the MP templates. This should prevent me from doing more harm than good. Have you had experience with them? Waste of time or worth the effort?
Thanks,
Perry

by **dave-r** » 03 Mar 2004 8:29

pscartozzi wrote:I also wanted to see if Desktop Dyno predicted anything close to the actual performance.

Yes it does. It is a very good guide to how your engine will turn out. Of course the better the information you input the more realistic the result.

I've read through the Hughes website, and yes, they explain why their cams are better. The Crane website lists why theirs are better, the MP website lists why theirs are better. I was trying to get the opinion of people who have had more experience with the different grinds/manufacturers. I'm aware of Hughes and their reputation.

No,no,no. You are reading the SALES pitch.
You need to understand how a cam works, what cams do to make power, what parameters to look for. Then make an informed choice based on sound physics and theory. NOT hearsay or sales pitch. I always point people to the Hughes site whether they want a Hughes cam or not because it explains cam theory better than any I know. Too many people just do what other people do. Don't fall into that trap.

Do you really feel that my 452's flow better than 906's. I have a set of each to choose from.

As stock they flow about the same. If you have both put them side by side and compare. You will see they look the same. Up to a point they can be ported the same. However the 452s can be ported out easier when it comes to a really big port job. The 906s need a little welding. Plus as you say the 452s have the hardened seats already. So they are perfect for the home port job you are thinking of.

The templates are fine for a mild street/strip engine. Use them to define the size and shape of the ports. Then blend it all together so there are no 'steps'. Shape the valve guide into a teardrop shape and smooth the edges on that too. Get a three angle valve job as well. There are also valves on the market that flow better than stock.

by **440Wedge** » 03 Mar 2004 17:43

http://www.nhra.com/tech_specs/engine/b ... HRY-78.rtf

by **dave-r** » 04 Mar 2004 8:58

That is one of the most useful websites I have seen ever. Thank you VERY much!

sounds good Dave