im purchasing a pickup with a 4.9l efi engine and want to document my progress with it here for others to learn from.

I plan on doing a rebuild with the engine to make sure it'll handle the increased air.

I'll modify an exhaust manifold and put a turbo flange on it. My turbo of choice is from a 5.9l cummins engine.

Since I plan on only running about 5lbs of boost, ill plumb in two small wastegates because a single large one is a bit expensive.

I will be using a Megasquirt computer to control everything.

 

AlphaZ,

Arrived to this post from your 240 build up post. I'm more interested in asking if you ever considered upgrading the 240 to a 300? I've been reading where the difference is the stroke. So with a crank, rods and pistons, you could take advantage of the work you did to the 240/3.9L and make it into the 300/4.9L you seek!

At least that's the theory. I have a 66 Custom 500 2 door sedan that has a 240. I'm looking to rebuild the motor but was thinking of stroking it to 300 and making the rest of the intake/carb/header upgrades. There arn't too many people in the Galaxie community that desire keeping the I6 in their car. At least I haven't found them yet if they are out here!

That's all I know for now...
Steve in Flat Rock, MI

 

I like this idea..but whatever idea you take..both are strong choices!!

 

I'd like to try this as well at some point with a HE351VE off a newer 6.7.

 

Well, the 240 is the original engine bored .040" over and about 50k miles on it. It's suffered the majority of my brutal teenage driving years. I regularly spun it up to 5,000 rpm and at times 5,300 rpm. It's now starting to burn oil and have a bit of a knock after it's heated up. Still runs strong, and I considered changing the crank and rods, but it would be an overhaul anyways. Don't forget that the combustion chamber on the 240 is smaller than on the 300 and will raise your compression ratio. (My '67 F100 is my daily driver, so it would put me out of commission for a while if I took it out for a rebuild also).
My 240 has a compcams 268H cam in it, and considering the 240 has reduced stroke compared to the 300, the low-range torque suffered a lot more than I expected (something for you to consider). The offy dual-plane intake works well for high-speed intake air. I had a very difficult time tuning (still haven't gotten it perfect) the Holley 390 vacuum secondaries carburetor for the 240. The headers, which I may have torqued incorrectly or not kept torquing correctly, have warped on the first cylinder and leaks because it shares bolts for the intake and exhaust. Also, consider a stainless flex fitting for the torque exerted on the exhaust system. I've fought for over 2 years on the collectors leaking where it meets up with my exhaust.

As for my current build (update), the engine block is at the machine shop and needs to be bored 0.060" over. My machinist said he can get forged pistons, a requirement for forced induction. I also have him on the search for a hydraulic roller cam, or at least a blank that they can cut. I chose the roller cam on the basis that it will be more dependable and free up more horsepower. The current engine oils just don't have the zinc in them for a hydraulic flat tappet and I know I can use additives but I'd prefer to be more proactive on it.
For the turbo, I'm going to use a hx35w turbo from a cummins 5.9L diesel. I'm leaning towards the twin-scroll design to help with reversion (google it, wikipedia explains it better than I do). If I read the compressor maps correctly, it should be about perfect for my application and not too hard on the wallet.
Oil cooler will be mounted in front of the radiator.
Intercooling will be a fun project, I'm planning on using a water-air intercooler, using an electric pump to circulate fluid to the bed of the truck and having the radiator from the donor truck mounted in the bed to cool the fluid. Reprimand me if you must, I'm a bit of a newbie at all this.
Megasquirt will be running the fuel injection on all this, and I really have no clue on how this is going to be figured out yet. I'll cross that hurdle when I get there. I know it'll work, I just don't want to worry about it right now.


I'm writing these things out as they come to my mind, if you need me to explain anything better or if I've been too vague, please let me know.

 

I talked to my machinist and he found forged pistons for $450. He did the calculations and it would be 8.99:1 CR. He said he would see if they had anything that would put it closer to 8:1.

 

Currently I have a 302 with a rpm airgap, Holley 650dp, longtube headers, I mild cam ext. It will be put in my 78 f100 project. However my dad just bought a 93 f150 with the 4.9 I6, 5 speed. I drove it for a day and fell in love. So now I'm contomplating a 300 I6 turbo build for my f100. Something that would max out at 10 psi. It would have to be carb though. I just refuse to put a computer in my truck. However after all my research it seems everybody that's turbod a 300 went with ego. Good luck on ur project. With the long stroke and a turbo what kind of torque numbers you think it'll be puttin out?

 

efi not ego sorry damn spell correct

 

Keep in mind that these are power numbers at the wheels and your drivetrain may affect it..

From research I've done and other people's dyno numbers, @ below 10psi, a conservative range is from around 245hp and 400ft-lbs of torque to 250hp and 450ft-lbs of torque.
At boost pressures at above 10psi, the highest dyno run I've seen was 260hp and 573ft-lbs of torque @ 18psi, which was on a chipped piston also.

I've read that most boosted 300s start running into detonation around 11-12psi.

If you decide to put a turbo on your 300, the MINIMUM if you want to have your engine around for a while is forged pistons and high temp exhaust valves. If it's high mileage it needs an overhaul.

I first considered putting a blow-through 300 turbo in, but I didn't want to do the modifications to the carburetor and I thought I would have issues tuning it. In theory, you're supposed to retune your carburetor when it gets cold/hot because your mixture changes with the weather. When a turbo is put on top of that and detonation is a key failure to a turbo engine(without forged pistons), can you trust yourself to keep on top of the tuning to make sure it's perfect? I'm assuming it would be a daily driver.

Currently I'm doing my research to find the perfect daily driver turbo with a max rpm of 4000, maximum psi around 12. I'm going to make a custom turbo from turbonetics and so far I'm thinking these numbers may be close:

T3/T04E hybrid
57trim compressor
Ceramic bearings
Water cooled
F1-57 turbine wheel
.65 A/R

Anyone have thoughts?

 

My plan was to run forged dish pistons for 8.0 to 1 compression, a wideband o2 to aid me in tuning, a 600ish Holley modded for blow through go through the head completely port and polish, inconel valves. Also I've heared you can run gm roller rockers. A high volume oil pump and an oil cooler. I want to run an intercooler and possibly water/methanol injection to help resist detonation. I'd like to run forged rods and crank however I'm not sure they're available for the 300. My goal is a reliable daily driver that gets respectable mile while not under boost that will last me a long time. Something with more low end torque then my 302 with decent mileage and longevity. 400 ftlbs of torque at the wheels at a nice low rpm is plenty for me. Like you I plan to rev to a max of 4000rpm when I feel like drivin hard, but this wouldn't be often. I look foward to seeing how your build turns out as I plan my own.

 

I have access to a 3 axis Haas cnc machine. I was thinking about machining an aluminum head from scratch however the r&d is something I'm not so sure I want to do. I was thinking make a duplicate of the stock head out of aluminum with bigger valves and ports. Mainly because in theory the aluminum would shed heat better to help further resist detonation. Just a wild outside the box thought.

 

Update on progress...

Turns out the guy my machinist had been talking to didn't know what he was talking about, so no go on forged pistons. I could have customs machined, but it would be too expensive to do ($600-$700).
Consequently, I plan on running hypereutectic pistons. Since I have to take extra care and keep my pistons from chipping (or exploding for that matter), I will not use an intercooler and rely directly on methanol/water injection.

Some of you may scoff. I've done my research and believe meth/water injection would be far more. . .consistent since outside temperatures where I'm at can range from -15 to 110F, depending on season of course.

Since the injection is more consistent, I don't have to worry (as much) about external temperatures. Therefore, detonation or preignition will be a less likely issue.

Q: Why not run an intercooler and injection together?
A: The only aesthetically pleasing place for my build is to put an intercooler behind the grill, in front of the radiator. Since it gets very hot, I could run the risk of overheating the engine from lack of flow . . . consequently increasing risk of detonation since (I believe) injection systems work off of manifold pressure and couldn't help in that situation.

I'm also looking at a turbo cam from ISKY that would be useful, except it shows a maximum boost pressure of 7psi.

I hope that my research and insight for my project has helped anyone else.

 

After some searching, I did find a place with hydraulic roller cam blanks, but they said the price would rack up to $835, not to mention not having a ready supply of roller lifters handy. Seriously considering it, nobody I'm aware of has ever put a roller cam in a six.
Did some more searching on the lifters, it seems the lifter bore is the same as a 460, so a person could make custom tie bars and then use 460 hydraulic roller lifters in it.
The only justifications I can think of to make this worthwhile is that:
1. I won't have to use an additive or special oil for the flat tappet cam
2. No worries about proper break-in technique
3. Better efficiency
4. Lower oil temps

 

I'm sure you've heard about others that make crossflow heads by chopping up 351? heads and welding them together. Why not take that a step further and "chop" up a v8 head on paper and piece it back together and have the CNC machine build it? Not much R&D for finding how to make valves and ports bigger then. I've heard of big numbers from people doing it that way.

 

subscribing to this thread, what all entails of adding the megasquirt and where would i get forged pistons? if i run lower boost can i use stock pistons, if not thats oaky. also how bad is fuel mileage affected