I am new here but I have been combing the forums for information for a while now before posting. I have a different sort of question that I have not found an answer to. I am looking for input on my build. Many times I see people asking for engine build suggestions using an RV based 440 that they are putting in their street car/truck. I am looking for suggestions of what to do to my RV 440 that is staying in my RV.

I have a classic 1976 26' Executive RV that has been in the family since new. Over the last 20 years it has been completely restomodded with a complete new interior (including all new technology), new suspension fully upgraded, and many external mods to the original 440-3.

The motor is getting low on cranking compression and using oil. It still runs fantastic, but it is due to be pulled and gone through. I want to get the most out of it while being realistic that it is in an RV and will never go down a quarter mile. It lives between 2,500 and 3,500 rpms and never revs past 4k.

Engine is a 1976 440-3 with a cast crank. Stock low compression (8.1:1 advertised in the service manual)

What I have done to it externally:
Professional Products fuel injection system
MSD ignition
Comp cams recommended cam for this engine, advanced 4 degrees at the timing gear (forget the specs, but built for low RPM torque).
Thorley long tube headers and free flowing single 3" exhaust
Electric fan conversion
Recurved the distributor for 38d total advance, vacuum hooked to manifold vacuum. Runs well and does not ping on 87 octane.

Goals: To get the most out of it that is realistic for a motorhome where I can still use 87 octane fuel, and get the most efficiency and power I can reasonably get.

The mods I have done have all increased performance and economy over stock and it runs pretty darn well, all things considered. I just can not help but think increasing compression a tad and doing some clean up on the heads will make a significant difference. So I need your suggestions. American iron is not my strength, but I am a very good mechanic and willing to learn from you all who are much more knowledgeable about these than I am.

Jay

 

Welcome.

Sounds like your on your game. With a short block rebuild and a compression increase I would be looking at Step Pistons, they have a raised pad that can give quench with open chamber heads. A port and bowl clean up will help, I would also smooth the combustion chamber to stop hot spots.

When the heads come off the valves and seats may tell you to get new exhaust valves, something modern and heat dissipating.

https://www.uempistons.com/index.php...e5d682c95d2072

 

I agree on the 1-point increase in compression.. I'm also in on everything else... Only thing I might swap would be look into a cam that might work a little better in the rpm range. Wait on the cam till you get all the numbers of if the block will need to be bored or not.. At that point you could get very specific on whats needed...


Welcome to the site.... Keep us posted..... Sounds to me like you got a good plan going....

 

Possibly a gear vendors overdrive ?