Greetings all. I have a couple of questions reagarding a 460 I have in a '72 3/4 Ton 4x4, that I use for hausling a 6 horse trailer,and cows/hay. It's about a '79 motor, low compression. Im looking for ways to increase performance without breaking the bank.
Does anyone have any experinece with DOVE heads, and what exactly are they? Wil they increase CR enough to make a difference? How about turbos on this motor? Thanks
Ron Zaccagnini

 

Hmmm.. Modifications without breaking the bank, eh? You mentioned the DOVE heads.. on your '79 engine, with the lower (8.3?:1) compression ratio, these heads would benifit greatly. Your compression would be increased to between 10 and 10.8:1, which would result in significantly more horsepower and torque..at the risk of detonation when using pump gas.
Have you thought about a camshaft swap? I would recommend an Extreme series truck cam from Competition Cams.. They sell entire kits (cam, lifters, springs, etc) for not a whole lot of money..
I would recommend against turboing the engine. This requires much fabrication and, at that, a lot of money and time involved. Unless you have access to a couple turbos, and a lot of pipe and the equipment to bend it, I would say this is out of the question if you are thinking about cheap power..
Any more questions, comments, etc.. by all means, post back!

J/.c

1965 Ford Galaxie 500 (I know, it's not Quite a truck..)
1974 Lincoln 460/ C6 Transplant, 9" rearend
380hp/5100 rpm, 526lb.ft./3870rpm
stage 3 shift kit, Megashifter, SSI cam, Mallory ignition
Best E.T: 13.78/106.2mph on street tires

 

one of the cheapest, may not be the least amount of work, would be installing a pre 72 timing chain and gear set. this sits the cam straight up and not retarded.

 

Gallery- thanks for the note. I am told that I just 'WON' the set of DOVE heads on ebay. They looked nice form the photos...will need valves and minor attentino. However, I am now wondering if, as someone said, I need apecial pistons in order to use them.. Tell me I can use them with my stock pistons....right??

I already have the straight-up timting gear and chain in it, and am thinking about a cam and manifold. Cam: 260 deg. duration, right?
Thanks!

Ron Zaccagnini

 

You'll be very happy with the D0VE-C's, you will have to be careful with pushrod length due to the taller deck on your block as compared to the block the heads came on. I used CJ+.200" for mine, '79 truck block w/D0VE-C's, both just decked/shaved true-just a little removed. The compression ratio is just tick below 9.45 to 1. A little port matching and smoothing of the hump on the exhaust side will do wonders (easy 20+ HP just by doing this). The cam sounds about right for a worker, look for a dual pattern with a little more on the exhaust side as compared to the intake. When in doubt, call several of the cam makers, they are usually very good to work with when choosing what's right for you and your truck.

 

The D0VE heads will give you right around 9.5:1 CR. Not 10:1 or higher as previously stated. They are a wonderful improvement for your engine. I would recommend the Xtreme 4X4 series from Comp Cams. I think someone already mentioned these cams. I currently run the Xtreme 4X4 cam part #34-235-4
Specifications:
* Advertised duration: 262 intake/270 exhaust
* Duration at .050 in. cam lift 218 intake/226 exhaust
* Gross valve lift: 514 in. intake/524 in. exhaust
* Lobe separation: 111 degrees
* RPM range: 1,400-5,600
* Good mid-range, largest for stock converter, heavy towing, * 4.10 gear, noticeable idle

Contrary to what Comp says, I would actually say that with a 460 you could get away with the next larger cam and still use the stock converter. I have absolutely NO loss of low RPM torque. Overall I love the grind. Tons of torque, (it'll spin the tires taking off in second with 3.25 gears) and it has hp out to past 5000 RPM's. Heck of a passing gear. My truck will run 90 in second gear!!

 

Thank you gentlemen, for the input. Im excited about getting it going now. I am still unclear on one thing and that is reagrdgin teh pushrods. Do I need shorter rods, and if so, are these a sotck Ford option? Will that be evident when I look at the heads?
This Ford is a work truck with a stock 4 speed, not a dragster. It'll be spending its life pulling a 6 horse trailer and hauling hay... But I do look forward to driving it on the road..

Thansk for all the tips.

Ron Z

 

Sorry, should have wrote this out, the pushrods are CobraJet plus .200", the CJ length stock is 8.550" (I think, I'm close if this isn't correct, but it's not in front of me right now!) so I used an 8.750" long pushrod. The deck height of the 79 block is taller than the '70 block, farther from the lifters to the rockers in the '79 with an early head. I used a pushrod length checker to come up with this length then shopped around until I found what I needed in a hardened pushrod. I think this method would be the best to make sure you have proper valve lift and operation. I think I paid 12-14 bucks for the checker-well worth the price!

 

Hey guys,
I just learned alot of info from checking over keith blacks piston selection pages. Some of it's related to this discussion about comp. ratio's and pre-71 blocks etc. http://www.kb-silvolite.com/page48.htm
I've heard that if you use the truck for towing, keep the comp. ratio down under 9.0 or as close as possible. Alot of this next article talks about using hypereutectic pistons, but there is good general info here also. http://www.kb-silvolite.com/page05.htm The bore diameter of 4.360 is bigger than most other big blocks and provides more area for detonation away from the spark charge. Higher compression adds higher heat making detonation 'knocking' happen more quickly. Helps include running a cooler thermostat and doing that quench or 'squish' area computations for their pistons.
Just thought I'd throw this information in as I'm in a 460 buildup process also.
Tony G

 

I'll be installing DOVE heads on the 460 in my 78 sc sometime early next month. Here's what I plan to do: DOVE heads w/mild porting, stock 2.08/1.66 valves(might go larger on the exhaust valves when I have the hardened seats installed), 750 holley, Performer intake, .484/.510 lift 204/214 duration@.050", timing chain set from 68-71 and L&L shortie headers. I ran this combo on DesktopDyno 2000 and came up with 413hp@5000 rpm and 522lbs torque @2500 rpm. It also shows over 500lbs torque from idle to 4000 rpm.

 

It
>also shows over 500lbs torque from idle to 4000 rpm.
>

That's an impressive torque range. Wanna build one for me?.. Just kiddin. I've read where the 'regular' 460 heads had optimum flow at .531 lift.
http://www.amotion.com/fbb.html
I don't know if *regular* is compared to 'dove' heads or 'FI' heads which they mention as '87-'91 heads just before.
You'd probably have to increase duration slightly, but hopefully not overlap the intake/exhaust. What would that do on desktop dyno?
I left my cam choice up to the engine builder. He plans on running a similar cam as yours, but I'll be using regular '87 heads. I thought about performer intake, but I've heard about the aluminum/cast battle that goes on between the heads/block assy and the intake. It's tough enough to get the cast one to stay sealed. For now, I guess i'll go with the cast one as I've also heard that the performer isn't "that big of a change in flow". I'm concerned that I might be maxing out the 650 cfm carb. I think my rev limit will be about 4800 to 5000, which is plenty high enough, but with a different cam, I wonder if I'd be better off with the lean version of edelbrocks 750CFM. The concern I have is having enough flow in the 2 barrell mode to feed the engine in light/med duty towing and highway cruising.
Good input on the 460 buildup.
TonyG

 

As far as the bigger bore equalling more area for pre-ignition to occur, I'm not sure if I buy that. Provided that you keep CP at 10.5:1 or less, even with iron heads, and you do all the other little things you'll be fine. Right now I'm running just over 10:1 with iron heads, of course the combustion chambers have been polished (no sharp edges to get hot and cause premature ignition) and I'm running 93 with full timing. 91 will give me some pinging at the right throttle only after the engine is hot. I'm also running a 160 degree thermostat. The bottom line is for a given air-fuel mixture whether or not it pre-ignites depends on temperature, pressure, and any ignition sources. Size doesn't matter (just ask my wife!!) Ha Ha!!!

As for the intake questions, I'd go with a Stealth. Millions of people have used aluminum intakes on iron blocks and heads without any problems. The gains you will get will be worth the money spent. I wouldn't go with the Performer as it is only slightly better than stock, but the Performer RPM or Stealth are definitely better in all cases. The only scenario where a Stealth would not help or might even hurt would be in the case where the rest of the engine was completely stock. If you do anything to your engine beyond stock, it will benefit from the better intake.

 

>As far as the bigger bore equalling more area for
>pre-ignition to occur, I'm not sure if I buy that.

That was mostly from some information I've recently gathered while searching some websites for "detonation". Detonation is different from preignition. Detonation comes after the spark ignites but before the flame kernal can spread all the way across the bore. It can lead to pre-ignition because of the extra heat generated or vice versa. The larger the bore, the more area the there is that the mixture has to fill. Here's a quote from http://zhome.com/ZCMnL/PICS/detonation/detonation.html

"Inherently, small-bore engines are less prone to detonation than those with larger bores. The less distance the flame has to travel, the less likely there is for something to go wrong."

Preignition comes before TDC and is from engine heat igniting the fuel misture. Your right about polishing chambers, and running a cooler thermostat.
Here's another info site I found with a little more technical aspect.
http://www.motorcycle.com/mo/mcrob/rt-fuel2.html

>Provided
>that you keep CP at 10.5:1 or less, even with iron heads,
>and you do all the other little things you'll be fine. Right
>now I'm running just over 10:1 with iron heads, of course
>the combustion chambers have been polished (no sharp edges
>to get hot and cause premature ignition) and I'm running 93
>with full timing.

I guess I'm trying to be cheap with my gas bill. I'm planning to stay at or under 9.0 with standard pistons and a mild overbore. I figure with any shaving that was done to the head and block, plus the overbore, it will only raise my comp ratio 2/10 or so. I hope to get away with 87 but can go to 91 if I have to or even 93. But if I have to run 93 then my timing is probably off.

>91 will give me some pinging at the right
>throttle only after the engine is hot. I'm also running a
>160 degree thermostat.

Are there any dangers in running "too low" of a thermostat? The book calls for 210, but I was going to go with a 185 or 190. Maybe I'll go lower.

>As for the intake questions, I'd go with a Stealth.

Yep, If I end up going with another intake, it will probably be the Stealth dual plane from Weiand. There is another discussion in the 385 forum about that which I read last night. About the only performance mods I've done are a K&N filter and headman headers. I also run platinum plugs. I guess those two mods are enough to make use of the Stealth, but we're on a budget with this project also. I'll see what I have in the engine first and then decide.
Tony

 

Long, but hopefully worth it.

Sorry about the confusion. My fault. I meant to say that as far as bigger bore equalling more room for detonation, I'm not sure I buy it. Detonation, as it is usually thought of, describes a condition in which the air-fuel mixture reaches a high enough temperature and/or pressure to "auto-ignite". The size of the bore should have little if anything to do with this. If you take a given air-fuel mixture, whether you have a thinble full or a tanker full, if it gets to the right temperature and pressure it will auto-ignite. The absolute amount has nothing to do with it.

When I said "pre-ignites" at the end of the first paragraph in my last post, I didn't mean "pre-ignition" in the strictest sense, which is usually thought of as the premature ignition of the air-fuel mix by some ignition source. I meant it in a sense of any condition which could lead to improper timing of the ignition, including both pre-ignition or detonation. Most people don't describe detonation as having anything to do with the timing in relation to the spark provided by the spark plug or in relation to crankshaft position. It is simply auto-ignition of the air-fuel mix. As far as true pre-ignition it really has nothing to do with crankshaft position either. You simply have a condition where a "hot-spot" causes the air-fuel mix to ignite. That ignition source could possibly be your spark plug, either by being the hot-spot itself (those babies can get really warm), or if you have the timing too far advanced.

Anyway, these are all just technicalities and semantics. I'm just not sure whether I would trust KB pistons or their tech advice. I've heard too many horror stories regarding their pistons, especially in big-block Fords.

Low temp thermostats,
It has been hypothesized and testes by many people that an engine will make the most hp at higher operating temps. However, in real-life tests of big-block Fords (and that's what we are talking about) lower temp thermostats down to 160 degrees have been shown to actually increase hp output. Also, I have heard that an engine will show increased wear with lower operating temperatures. The degree of this increased wear is unknown to me. I think these two things bascially come down to how hot your engine is actually running. Just because your thermostat is 160 degress, don't think that the heads, pistons, oil, crank, anything is really that much cooler than compared to when running a 190 or 200 degree thermostat. Don't underestimate the ability of 460 cubic inches when it comes to the generation of heat, especially when the CR is bumped up to 9.5:1 or above. Later.

JJ

 

The reason that an engine with a bigger bore is more prone to detonation is that it takes longer for the flame front to travel from the spark plug to the opposite side of the cylinder. Because it takes longer for the flame front to travel across the bore there is more time for the temperature and pressure of the fuel/air charge at the side of the bore opposite the spark plug to build and therefore cause autoignition of that part of the charge. For this same reason locating the spark plug in the center of the combustion chamber like the Jim Feuling heads for the 460 significantly reduces the likelihood of abnormal combustion. This in addition to other factors on the Feuling heads allow compressions ratios of 12:1 on 87 octane fuel.