Many moons ago I built an LS-6 engine, yes that is a Chevy rat engine. Customer wanted the jacked up compression ratio-something around 11.25:1. I told him he was crazy as at the time Union 76 was the only service station still selling leaded gas. Nothing doing he wanted the high compression. So is was. Sure enough death rattle occured. What to do? Well Edelbrock had a water injection system where you could use a water and alcohol mix to kill the detonation/death rattle. Whadya know it worked. Dunno if any aftermarket mfrs. still market water injection. Aircraft have used it since the 1940's. ADL is what it is called in aircraft. See tanks of it at the Reno Air Races each year. Has a lot of benefits as it turns to steam according to claims and that removes the carbon if any from the combustion chamber, and that eliminates hot spots as glowing carbon can be a defacto ignition source causing the detonation. So there should be water injection systems out there for performance motors. Too expensive to run race gas and the last time I called an airport for the Avgas approach they told me the the company that supplies fuel (Shell) forbade its use in anything but piston aircraft. No doubt because it had a lot of lead in it. So I never got to try leaded high octane Avgas in my flatbottom V-drive. Octane rating was 130 I recall. Also helps to polish the combustion chambers to make it harder for carbon to buildup. Different strokes for different folks.

 

Now there was a dude living in 1970 even when the LS 6 was new in 70 or so it needed premium leaded and would still rattle under the right conditions it was basically a race engine dropped in a street car.. The SCJ on the other hand could live on regular leaded if they were not pushed too hard.

 

Okay, trying to understand all of this. So the 70 Dove wont work for today fuels is this just a valve seat issue? Do I just need to have hardened seat out in?

I also can get a 74 460 out of RV which I assume will have to have hardened valve seats as well. If I rebuild the motor what do I need to do so it is good to run regular gas any octane?

 

True hard seats are inserts made of very hard material like Stellite, or other hard metal. In my experience only, I have used them one time, at the customer's request. He wanted a propane motor and insisted on them. Done deal. Propane has little if any lubricating properties so the inserts are required to stave off valve recession. Oh I have I used one or two to save cylinder heads where someone had sunk a valve too deep from over grinding the stock seat making the valve tip high and geometry way out of whack. The factory usually uses flame hardening on the cast iron seat to save costs I suppose. Never seen old Ford cast iron heads with factory hard inserts.Aluminum heads have them for good reason. Nothing wrong with having hard inserts placed in cast iron heads if you so choose, be aware it isn't cheap.

 

The D0VE heads are fine on today's fuel. If you use the right pistons to bring your cr down to around 9:1, no problems will occur. You can run 87 or 89 octane with no issues. Most people rave over the D0VE heads for higher horsepower, mostly in race applications. If you are going to rebuild the engine anyway, I would get the RV engine and rebuild it stock with a straight up timing chain, aluminum intake and 4V carb. This will be plenty powerful enough for a daily driver. No need to over build.

 

I had a 73 with a 390 and had valve seat wear out, mechanic told me it was due to today's gas having no lead. I had the heads redone and hardened seats put in for 150.00 for both heads. Now that was 10years ago and maybe it was just a FE engine issue.

 

If I can get the RV motor at right price I am gonna get it. Seller says it's running but it's already pulled and I ain't taking chances so I am looking at it as a core. I can hear the dove engine run and its $600.00

 

If you can hear an engine run and it sounds good for $600, get it and just drop it in your truck. No messing around. If it ain't broke, don't fix it.

 

It will work just fine on today's fuels in fact it will run better than on fuels of 10 or 20 years ago which was a real low point. To make it handle any fuel with no issues I would not go above 10:1 with early 385 heads. And just don't get too aggressive with the total ignition advance and you will be fine. People seem forget the 385's with the early heads are able digest higher compression than comparable motors. They will run a full compression point more than the BBC on the same fuel.

As for valve rescission this has never been an issue on the 385's with unleaded. Generally this is not much an issue with most of the Ford V8's as the valve seats were much harder than the comparable GM engines. Even the old Y blocks stock heads can run unleaded with no issues. If you are going to be racing, spinning high RPM's quite frequently or running a fairly lean fuel air mix for economy, then you should up grade the valve seats as recession could then be an issue, but in normal a street application it will be just fine.

I just would get the DOVE engine drop it in and run it if it rattles a bit come back and we can help ya tune that out.