Hello everyone,

My '95 E150 is having some engine issues that I think are related to the head gasket. It used to slowly drain the coolant but after I put in some head gasket fix it stopped that issue. Now it feels like the gasket might have failed between the cylinder walls.

I'm thinking I would rather spend money on new aluminum heads than have the factory ones sent to the machine shop to freshen up. So I've searched to see what's an affordable set of heads that have a good reputation. I've narrowed it down to the LMR SVE heads, 56cc chambers & 170 intake runners.

So my question is, would these heads cause the engine to have too high of a compression ratio & force me to pony up for premium fuel? I did the math and I figured it'd cost me about $800 a year extra in fuel in I had to go with premium fuel. Pretty much the cost of a better set of heads with a larger combustion chamber and not deal with the higher compression issue.

I figured I'd keep everything else factory, I was tempted to change the camshaft but I don't want the computer to act up. Not sure about rockers, the cost of those are pretty high & if I don't leave it factory I may just do the cheap option and go roller tip. If anything I figured I'd go with 1.7 rockers to help the factory HO camshaft wake up a bit.

So what say you gentleman, and gentlewoman,

Would the compression be too much or somewhere in the middle for me to use mid-grade fuel? Also, I could pony up an extra $500 and get their cnc ported heads, that opens up the chamber to 58cc. But it's probably splitting hairs at that point.

Thanks!

 

Others will chime in I'm sure, but consider these:
Pros: Higher compression will lead to a little more power and better fuel economy.
Cons: Whatever your added cost is for premium fuel, it will be that for the rest of your engine's life.

Does your engine have knock sensor? If so, it may automatically retard spark timing when the engine knocks, counter-acting the Pros.

Don't waste your money on roller tip rockers; the benefits over stock are almost insignificant. If you want to spend money on rockers, save up for the full rollers. The benefits come from reducing friction at the fulcrum. Stepping up to 1.7:1 from 1.6:1 will be a minor cost increase, but gain a noticeable performance increase.

 

I'm not sure about the knock sensor, my knowledge is pretty limited on details like that. I'd like to carb swap it but don't want the hassle of a transmission controller expense.

I wouldn't mind the higher compression in a lighter weight vehicle, I just figured it'd be wasted on such a heavy vehicle like my E150. The rear has been gutted & I only have one bench seat in the back from a Transit so it's pretty bare compared to when it rolled off the factory but still pretty heavy. The transmission was rebuilt about 2 years ago, & I upgraded the coil springs, leaf springs & shocks to all HD towing versions. Also upgraded to 17x8 aluminum wheels on to get rid of the shake from the old steel wheels being so off balance.

If it wasn't for all the money I already put into it, I'd be more inclined to buy another vehicle that's running. I'm already halfway tempted to do that & park the van till I have the money & time to fix the van. My backup ride is having issues now as well so I'm in a bind to get another running vehicle soon.

 

The 2.02" intake valves on those heads will probably be an issue, unless you plan on changing pistons.

 

Much of SB Fords losing coolant can be traced to the intake gaskets - weeping from the end coolant passages between the heads and intake manifold. They can leak out (and you'll notice an anti-freeze smell before you see any weeping), OR they can leak INto the end intake passages (Cylinders 1 and 5 especially). This is especially true with an aluminum intake manifold. Get a bit of corrosion starting under that gasket surface, and then next thing you know you catch a whiff of coolant.

Another issue with the intake gaskets is water pump output. When I built the 393W a few years back, it was constantly trying to push out the intake manifold gaskets around those front coolant passages.When I removed the intake, you could see how the gaskets had 'fractured' from the hydraulic pressure of the coolant right by the water pump. My car originally had a very large crank pulley since it only had 2.73 rear gears, and that large pulley helped with flow at low RPMs. When I upped to 3.55 rear gears, and was revving the engine to 5500rpm regularly, that made the water pump spin too fast, causing excess pressure.. SO I put on a reduced diameter crank pulley to make the water pump spin slower. Problem solved.

 

I appreciate the info, I hadn't thought that would be an area to worry about on the coolant. I had thought about swapping out the intake for an Explorer GT40 set but found out in reading on it that some of the lines would have to be lengthened to accommodate the different location of some plugs. Since I can't do the work myself due to a medical condition, I figured it'd be too much to ask for a mechanic to tackle the job.

I'll take a look to see what size pulley I have on the water pump, I don't floor it much if at all since I usually have my kids with me but I'll keep that in mind. My van has 3.31 gears in it now, but I've wanted to change them out to 3.73 or 4.10's in the past since it's such a turd when it comes to hauling heavy loads. I rarely go on the highway I usually only drive 55 at the main roads in the area, so it's shouldn't be a problem. I may yet in the future if I decide to go with fixing the heads now.

 

What trans, I would regear(410) if E4OD, be lots, and lots, of money ahead, and a smile on your face, when you git after it with 4.10's, vs the 331's you have now.

 

True, but I'm still having to fix the engine issue before I can consider the changing the rear end.

I have the 4R70W trans.

 

What makes you say that? Have you done a compression and leakdown test?

Possibly, your CR will raise to 9.9:1 but aluminum heads dissipate heat faster so it may not be too bad.

Your truck doesnt have a HO cam in it but its a decent truck cam, 1.7 rockers would help but this could be a rabbit hole that will get costly. If those heads use stud mounted rockers they will also have guide plates which require hardened pushrods that will be a different length than stock, that is something you will have to measure and order. So the truck will be down for a while.
The 5.0 truck intake is oversized a fair bit so IMO an aftermarket intake us wasted until the motor is pushing 400hp.

 

I guess I'm going to skip on those heads then, no way am I going to pay to put premium fuel in a heavy daily driver/tow rig.