Ok I know yall are thinking swap in a bigger engine lol but......anyone heard of a supercharger for a inline6? I have 1993 F-150 4x4 with the EFI inline6 and a 5spd. It needs a little more pep. I want to keep this little engine cause it seems bullet proof so far in my off road adventures.

 

I used to be a V8 all windsor guy until the day I bought my 93 f-150 with a 4.9 and a M5R2 5 speed... 2wd. then it was nothing but inline for me. the simplicity of engineering and design make the 4.9 not only indestructible, but very simple to modify. now to supercharge it, you have to make a lot of decisions before turning your first bolt. for a 4X4, a supercharger will give you gobs of low end torque, especially with that 3.98 inch stroke. but off road you don't want to over do it. too much compression will run it roughearly in the powerband which is where you want to stay in the mud. you'd probably want to bring your compression from 8.8:1 to about 10 to 10.5:1. lets say 10:1 for simplicity. so the atmosphere at sea level is about 14 psi. that means that right now. a natural aspirated 4.9 compresses 14 psi air 8.8 times 8.8 X 14 = 123.2 psi TDC compression. 10:1 compression will make 140 psi TDC compression so we divide 140 by the natural compression (8.8) to get about 16 psi that means that to achieve the same as 10:1 compression with a supercharger, you add 2 psi of boost. now with a positive displacement supercharger like a roots supercharger you can control a constant rate of 2 psi over the entire RPM range. Now lets use 1000 RPM as a base to calculate how much air this supercharger should move. at 1000 RPM your 4.9 moves 150,000 cubic inches of air and since were adding 1/7th more air (2 psi/14psi)
the supercharger should displace 1/7 more air into your manifold than your engine moves naturally. so 150000/7=21428 well add it. 171,428 cubic inches at 1000 RPM or 171,428 cubic inches per minute or divide by 12, 14,285 CFM so go out, get a supercharger that can displace 14,285 CFM at 1000 RPM and well talk about adjusting the fuel later. (its basically raising the volume by 1/7th as well) well Happy supercharging everybody and enjoy them 300's!

 

Take some time to research, then research some more. Call BDS out in CA. They can supercharge anything. They built the manifold for my 4-71 on my International Harvester 392.

 

you'd probably want to bring your compression from 8.8:1 to about 10 to 10.5:1. lets say 10:1 for simplicity. so the atmosphere at sea level is about 14 psi. that means that right now. a natural aspirated 4.9 compresses 14 psi air 8.8 times 8.8 X 14 = 123.2 psi TDC compression. 10:1 compression will make 140 psi TDC compression so we divide 140 by the natural compression (8.8) to get about 16 psi that means that to achieve the same as 10:1 compression with a supercharger, you add 2 psi of boost. now with a positive displacement supercharger like a roots supercharger you can control a constant rate of 2 psi over the entire RPM range. Now lets use 1000 RPM as a base to calculate how much air this supercharger should move. at 1000 RPM your 4.9 moves 150,000 cubic inches of air and since were adding 1/7th more air (2 psi/14psi)
the supercharger should displace 1/7 more air into your manifold than your engine moves naturally. so 150000/7=21428 well add it. 171,428 cubic inches at 1000 RPM or 171,428 cubic inches per minute or divide by 12, 14,285 CFM so go out, get a supercharger that can displace 14,285 CFM at 1000 RPM and well talk about adjusting the fuel later. (its basically raising the volume by 1/7th as well) well Happy supercharging everybody and enjoy them 300's!


Wow...thats alotta math!!! lol. Thanks for the info. I think that it would be cool to see a supercharged inline6. I bet that one would run like a rapped ape.

 

If your looking for "a little more pep" then supercharging is probably overkill. The is easily accomplished with a moderate cam swap and P&P the head, maybe injector swap and programming as well.

If your looking for a firebreathing truck with power and torque off the line...supercharging may get you there. Plan on having to spend some serious amounts of cash to get there, it's going to take a fair amount of fabrication as well as custom programming if you stick with EFI.

 

Umm...am I just reading this wrong? It's possible I just misunderstood what you typed, but I don't think I did.

Did you say go find a blower that displaces Fourteen thousand two-hundred and eighty-five cubic feet per minute? Teflon-coated and overdriven 8-71's (much too large for that engine) don't generally push over 2000 cfm tops. If I see an 8-71 with two King Demons sitting on top, I think the guy is clown shoes. Your design would call for 15(!) King Demons...at idle. That is so much air it's not even funny.

You should calculate your flow rate at maximum rpm, not minimum, as well.

I agree with the statement that RESEARCH is the key to success. Pick up a copy of Corky Bell's Supercharged. It has a ton of information, calculations, and advice. It's easy to understand, and will help you choose the option best suited to your needs.

 

He said cubic inches - so 100 cubic feet...

 

Hmm...I guess I just have a hard time reading it like that...it just didn't look right to me.

[edit: Oh, I see...he used 12 instead of 12 cubed (1728). Good call F350, and thanks for noting that for me.]

 

Now I'm not positive, but I believe a 300 cubic in. engine would move 300,000 cubic in. of air @ 1000 rpm. To get cubic ft. we divide by 1728 (that's 12x12x12) to get 173.61 cfm. I like working in %, so we take 1 and divide it by 7 and get .14285 times 100 and you get 14.285% increase. 173.61 cfm x 1.14285= 198.41 CFM @ 1000 rpm

Now take the same equation to get max CFM and at 5000 rpm the engine would normally would suck down 868.06 CFM but add 14.285% that brings you to 992.06 CFM. If you put it all together find a supercharger that pushes 200 cfm at 1000 rpm and 1000 CFM @ 5000 rpm, it should cover ya.
I don't know much about supercharging but I've always wanted to SC a 300. I think the problem lies in the fuel management. That's just what I've heard. There are 302's w/ superchargers, is the efi run differently? Anyways I'm looking for the most cost effective way to do this, I would think getting a fuel mngmnt system off another SC vehicle...say another 6 cyl and a Ford....how 'bout a Thunderbird SC say mid-90's? and a MSD 6 ignition? Vortech V-1 supercharger? Heddman Header? Like I said before I don't know much about supercharging but I need to know if this is possible. And within budget.

 

i made a thread about this in the 4.9L/300 section a long time ago. Might want to take a look at it there since a few good ideas were tossed around

 

IIRC, there was a company that specialized in Ford Inlines, cams intake manifolds header etc etc...

If you really want a SC then you are blessed because the inline design frees up alot of space under the hood for the DIYselfer...

Here is the link, they may be able to help...

http://www.cliffordperformance.net/

Then add this (not mine BTW...)

https://www.ford-trucks.com/classifi...6/limit/recent

Then this...

http://www.alanjohnsonperformance.co...s.html#49liter

These guys too...

http://www.titanengines.com/

 

I am looking at purchasing a 1994 Ford F150 RWD Flare Side with the 4.9L straight 6. I am looking for horsepower and speed rather than off road capability. What do you recommend? I am restoring the truck for my son.

 

For your review. Don't put too much power on top of the stock brakes:

https://www.ford-trucks.com/forums/1...nline-6-a.html

Same guy:

https://www.ford-trucks.com/forums/1...nline-6-a.html

Same guy, earlier effort:

https://www.ford-trucks.com/forums/1...6-sleeper.html


One of the few, if not only, turbo'd 300s that actually is finished and running and driving.

 

Swap in a 351w and turbo it.