Ok, for full understanding here’s what I have. It’s a 1992 F-250 4x4 HD w/ a ZF 5 speed, 3.55 10.25 rears/3.54 8.8 fronts in a Dana 50 4x4 axle, and a 5.8l/351 Windsor engine. Now, for about 10 years I’ve been hot rodding it around on a .030” overbore, most of that time with a stock set of E-7 heads that were shaved a bit, I think they were brought down to around 57-58 cc’s. I, about $300 or so short of actually doing the job right swapped out those heads with a rebuilt set of ‘93 Cobra Mustang 3-bar F-3 GT-40 heads because I’d blown an anti-freeze port out of the drivers side intake gasket and decided to upgrade. I also installed an Edelbrock Performer fuel injected truck intake, a K&N cold air kit, I swapped the brain and rewired the whole engine for a A9L Cobra Mustang brain and installed a 94 Ford Truck mass air meter, installed a Comp Cams 35-255-5 cam, an MSD distributor and MSD Blaster Coil, I even rewired the alternator from a G-2 to a G-3 taking the alternator amperage from 95 amps to 200 amps just in case and made a whole new set of 0 gauge 1/0 battery cables, starter cable, and grounds just so I knew it would feed that distributor and coil good. Now, it’s time for a rebuild, going to probably stroke the engine this time and may need a bit more overbore. Here comes my questions. Ok, it’s .030” over now and on the 2nd cylinder back on the passenger side it has a hairline scratch straight down the cylinder wall, so hairline that you can only see it by shining a flashlight on it and I can’t feel it at all rubbing it with my fingers, yet it’s either that or I roasted the rings because I’ve developed blow by in the last year or so, so I fear that I’ll need another .010” to clear that up and a fresh piston/ring set. On a stock E-9 cast block in an everyday driver 3/4 ton 4x4, is it safe to go to .040”, or will it start warming up a bit more than I’d like? If it helps I have the heaviest duty fan clutch on it that I could buy, when it blew that intake antifreeze port gasket before it literally blew all of it’s antifreeze out about 15 miles before I noticed it getting nice and warm, that was 20 miles from home, and it never went over the 3/4 point on the temp gauge on a 100 degree day or showed any real sign of being hot, so the fan clutch does make a difference, it would’ve roasted without it. Half of everybody always says “No problem!”, while the other half say that I need it sonic checked, which I have no clue what that costs or if the shop that I think I’m using even does that. Also, either way, I’m working the internal math on it to get the best power with the best gas mileage that I can get. I’m planning on trying to put a stroker kit in it and zero the block deck to the new pistons. Not sure wether I’m going to just put a 3.85” crank in it or go to the 4”, but either or I have a question. Those F-3 ‘93 Cobra Mustang 3-bar GT-40 heads are supposed to be around 64-65cc’s and then zeroing the block deck will work out perfect for a .042” thick compression quench (Fel-Pro head gasket thickness), but, if I want to try to still run 89 octane gas, or at most 91 octane, what’s about the best compression ration that I should go for with cast iron heads and block? I’m thinking 10:1-10.25:1, but if there’s a compression genius out there that’d like to chime in I’d appreciate it. I know stock 5.0l/302 HO’s were around 9.8:1 running on 89 octane gas just fine, so I feel I should be fine somewhere up to 10.25:1. I may be able to go a bit higher or need to go a bit lower though, not quite sure on that. Hopefully just one last thing before someone runs me out of here. Let’s say I go with the 4” crank kit. That’ll be 408ci’s to 410ci’s (dependent on that .030” over or .040” over on the cylinder bore). In the future I want to upgrade the fuel system (I also have a Quarterhorse data logger/brain tuner/chip programmer thing that I’ve been sitting on for a few years until I got closer to being done with it for a final brain tune) and was thinking for an everyday driver (with some kick) that I could just upgrade to the 460ci fuel pumps and 460ci 24lb injectors and that with everything else that I have now, getting ready to do, and a new BBK larger throttle body and probably larger mass air meter, that it would make a good solid combo that wouldn’t cost a fortune to change or drive afterwards and yet help keep my inner F-1 driver at bay. Would the 460ci’s fuel setup be enough for it though at over 400ci’s, upgraded intake, throttle body, GT-40 heads with 1.85” intake valves (may modify those for 1.94” valves, from my understanding the GT-40’s can grind out to a 1.94” valve) upgraded mass air, and running on a Cobra Mustang brain tuned out with the Quarterhorse, or would I need more fuel than that? Unfortunately I have to ask, I don’t have the money for extra parts that aren’t right, and I’ve actually asked these questions a couple places, either people don’t answer or do answer and don’t know the right answer to give and I’m going to begin tearing it down and sending it to the machine shop in about two weeks, so I’m down to my final numbers crunch on wether I need a different block to build or wether mine will take a .040” overbore, what would be the highest static compression to shoot for without going up on octane on my gas for a cast iron engine, and about how much fuel I’ll need for the 393ci-410ci small block category without going crazy. I like it to go really fast, but it is just a daily driver, it’s not going to the track or anything, so I’m going for as much as I can get without pushing it too far. Any engine genius’ out there that could help me figure these last couple details out would be much appreciated, I know how to figure my exact static compression, find piston dish cc’s, ci’s, all that good stuff, just not sure on the limitations of engine block materials, head materials, and what that does to the octane gas needed vs compression ratio “high-safe” range and how much fuel to run through that modified of an engine. I don’t need my fuel detonating before the spark plug goes off. Oh, and just for more precision/information, this will always be a naturally aspirated, no turbo, no NOS engine, so no need to try to figure those into the compression figures or fuel consumption/requirement figures, just a simple old “machine it damned near to the max” engine strategy. Anyway, thanks for reading, hope to get some good responses, and sorry it looks like a book.

 

What does 3.54 8.8 front in a Dana 50 4x4 axle mean? It would either be a Dana 44 or Dana 50 third member in that truck from the factory.

Second cylinder back on the passenger side from the front so cylinder #2 or second cylinder from the rear going forward so cylinder #3? I would think that either you or the machinist need to determine how much material needs to be removed in order to eliminate that scratch and go from there if the the block is still salvageable.

I don’t know anything about the aftermarket tuner programs but I’d imagine you could tweak it to run with those mods. There are people on here that would know those answers.

 

No they were 9:1 motors, in a heavy truck with regular gas anything more than about 9.5:1 is pushing your luck IMO.

The injectors size needed will depend on how much power the motor makes, and the cam you have now will be a limiting factor in that regard... and especially so with a ~400 inch stroker. I say have the block inspected and then weight your options, if it needs a fair bit of work consider looking for a roller block to use instead. You might just go that route anyway and keep driving your truck while it's built.

 

It does have a Dana 50 from the factory, the gearing on it is 3.54:1 w/ an 8.8” ring gear. I just tossed that in there so I gave the complete picture of what I was doing with the engine vs truck weight and gearing.

 

You’re thinking either an older one, mid 70’s, or you’re thinking about the 351 Windsor. I’m talking the late 80’s-mid 90’s 302 HO’s, they were 9.8:1, I have a Ford Parts Interchange guide that states all that kind of info based on the #’s stamped in the parts. Now a 351 Windsor in the late 80’s to mid 90’s was an 8.9:1 ratio, that’s probably what you’re thinking. That’s why they were gutless. I’ve already had it at 10:1 roughly when I had the stock E-7 heads on it that had been shaved down from 62cc’s to about 56-57cc’s, so I know that it can easily handle 10:1 and run like a beast setup that way, but I’ve always planned on going right around 400ci’s with it, so I needed the 64-65cc chambers and bigger valves of the GT-40 heads or it would be pointless trying to go near 400ci’s. What I’m trying to pull off is as close to 1hp and 1ft lb of torque per ci that I can get. The cam may get swapped too. I put that cam in when it was still on the old 92 truck speed density brain, so I was kind of limited, with the A9L Cobra Mustang mass air brain there’s a bit more room for a better cam for it. If I have to find a different block then I may try to find a roller block, but they only made 351 Windsor rollers from 94-97, so they’re fairly rare, twice as much as a standard block, there’s rumors about cracking around the cam bearings on them, and you only gain a few hp really for doing it, and maybe 30,000-40,000 more miles tops from less friction. I’d go roller if I got a good opportunity to do so, but it’d have to be a cheaper opportunity than what I’ve seen so far, the price difference vs what you actually achieve going roller really isn’t worth it to me. I’ve been doing this build a piece here and a piece there for about 11 years or so now while driving it the whole time and I’ve yet to find a 351 Windsor roller block that the hp gain and friction loss justified the price difference.

 

No I'm talking about the late '80s - early '90s EFI 5.0HO.. that was a 9:1 motor.
The 5.8 roller motors were not that rare, they were used in every truck line which includes full size cargo vans and cab n chassis versions of van and puckup chassis before the modular motors started appearing in those lines in '98, so shouldn't be that hard to find one.
The other issue that favors roller cams is the potential for a wiped cam lobe with a flat tappet at or shortly after breakin, this seems to be more of an issue lately due to the use of poor offshore cam cores and the lack of zinc in modern engine oils. I agree that the potential output from both versions is about the same though, given similar components.
1hp/cu in and even more torque is not hard at all, with either the Crane 444232 or Comp cams 35-320-8 the motor will make 350-360hp and 400+ torque but that takes a bit more airflow than stock GT40 heads can manage. With those hp tops out around 300 but the torque curve is much the same. Those two cams are considered EFI friendly and are not radical at all, there are lots more that could be used but those will produce a more factory like idle, vacuum signal, and overall drivability. If you get the motor up into that power output level it will need 24-30lb injectors but with a Quarterhorse attached it's not hard to make them work.

 

Its sad that you have been lead down, the wrong rabbit hole. see link-->Everything You Need To Know About 1979-1993 Foxbody Mustangs

 

From what I’ve read the Dana 50 is a 9” ring gear.

Source: Summit Racing


I picked up a complete F4TE engine from a ‘94 E-150 with 150K miles for $500. I guess I depends on what you want to pay.

 

I'll just add that the static compression ratio he should run will depend on the cam. A short cam will ping at a lower static compression ratio than a larger cam will. Stroking will make the existing cam act smaller, so that needs to be kept in mind when selecting static compression ratio.

I agree with the others that there's no reason to go much more than 9:1 static on an iron/iron daily driven truck motor running a reasonable cam and 87 octane fuel. Even with premium fuel I wouldn't go much past 9.5:1.

HP and Torque are determined primarily by heads/cam/intake/exhaust/cubic inches. Chasing 1-2% gains by pushing the compression ratio in a working truck engine is a fool's errand. One iffy tank of fuel on a hot day is all it takes to wreck an engine with ping.