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Ford Inline 6 4.9L with only 145 hp?

133K views 13 replies 8 participants last post by  454C10 
#1 ·
At least that's what the specs say. Is that realistic for an almost 5L engine?
What would be the (1) easiest, (2) cheapest, or (3) quickest way to get better performance out of this engine? What is that gonna do for the gas mileage?

Thanks,
GnrYmr
 
#2 ·
First, what year is it and what is it in? Injected or carbed?

This engine has a lot of potential, the 145 hp rating reflects a very mild tune and a lot of emission-ization.

You can do a lot with these, and they are torquey, good for street and truck applications.

Most of us that have had similar vehicles with the 300 cid 6 and the 302 V8 preferred the 6.
 
#4 · (Edited)
Size matters?

One thing you have to remember, if your vehicle was built after 72, the horsepower rating is differential rather than flywheel. That means that your eninge is actually putting out about 185-195 HP at the flywheel, and I am sure if you check the specs and compare, you will find it is putting out abit more torque then a standard 302/5.0 of the same time period. BTW, back in the late 60's and early 70's, in pickups, the 300 Was rated at 170 HP at the flywheel, and this was with 7.9:1 compression.
http://cliffordperformanceshop.com , is the website to go to for finding goodies for your 300 I-6.
They are very susceptable to even the most minor of modifications.
They are a very sturdy engine and will last quite long with good regular maintainance.
With a 4 inch bore and 3.98 inch stroke,veing a nearly square engine, dont expect to be able to turn them the kind of RPM you would expect out of a V-8 of similar state of tune and displacement. But then you dont have to.
Rule of thumb. Given a 6 and an 8 of similar displacement and state of Tune, the 6 will produce 30-40% more torque than will the 8 cylinder.
Torque is the real game, not horsepower, as horsepower is mearly a mathmatical formula to convert Torque to something people can relate to.
Knowing the year and type of induction system you have currently would help a lot. That being said, if its a carbureted version, an aftermarket intake, with a 390-450 CFM, vacuum secondary 4 bbl, and a set of headers with high capacity exhaust, would do wonders for your 300. Clifford makes intakes, cams, and headers, as well as some more exotic parts for your 300, and Offenhauser makes a couple different manifolds.
Recurving of your distributor is also an essential to getting the most out of your engine.
 
#5 ·
Although clifford is the inline specialists, they come at a price.

Good news, you can buy everything elsewhere and save$$$$ alot.

Any popular cam company has a camshaft for your engine, if low end grunt is what your after, the stock cam is fine.

Most all header companies will have something to offer, none are a direct bolt, all will require you plumb from the header to the existing exhaust pipe(s). Depending on application, you will have to notch the alternator bracket. If you have efi, there is a chance you will have to install an O2 bung and egr to header/exhaust manifold bung, depending on the brand/company, you use.

Efi exhaust manifolds aren't that bad, they consist of dual 3 to 1 manifolds, when in doubt, keep them if you have efi now or if you have a carb setup, consider them, as they are cheap if you look around.

If your carbed, Offenhauser intakes, sold by jegs, paw performance, summit racing, ebay, have an intake that will work and again, not cost an arm and a leg, as compared to clifford performance.

The real restriction is the head, if you can port or have that sucker ported, it will wake it up. The carbed head can accept a 1.94 intake valve easily.
The efi head, can but it will be shrouded badly, best bet with the efi head is the stock valves, if you must use larger valves, unshroud the valves and try and use more timing. As the stock efi head is a swirl/fast burn head and requires less timing than the carbed head to be efficient. You go changing the shape of the efi combustion chamber and you begin to work against its intended design, keep that in mind, also the efi heads are prone to cracking, some people have went through a few before they found a usable core. :)



Good luck
 
#6 ·
All Right Thanks for All the Replies!!!

First, what year is it and what is it in? Injected or carbed?

Ok sorry, forgot some of the most important info - as I said I don't have a lot of experience. I'm sure glad y'all have all this info for me! It's a 1992 Ford F-150 w/EFI.

~

This engine has a lot of potential, the 145 hp rating reflects a very mild tune and a lot of emission-ization.

That's what I was told every since I got it in 2002, and it runs really good for over 200,000 miles. I figured it was held back coming from 92. I finally took the muffler off before it fell off from all the rust working down here on the coast at the Naval base in Pascagoula. It's only got the converter, the manifold, and some rust :)



You can do a lot with these, and they are torquey, good for street and truck applications.

That's what I was hoping, I sure want to do a lot with it. As much as I can afford that is. It'll run with most cars even some 8s.



Most of us that have had similar vehicles with the 300 cid 6 and the 302 V8 preferred the 6.

I've always really loved it myself.
 
#7 ·
454 in a C10!!!

Don't feel bad, there has been plenty of 145hp 350 v8 chevys also.

I don't feel bad at all, as good as it runs - especially with all the miles it has on it! A friend of mine from the Naval base crammed an old caddy engine in a Lil ol' Chevy Luv truck. Originally he was gonna put a 350 in it, but somebody bet him he couldn't put the 500+ instead. So seein' as he was a Marine...
 
#8 ·
I Think I Got the Right Size, That's All That matters?

One thing you have to remember, if your vehicle was built after 72, the horsepower rating is differential rather than flywheel. That means that your eninge is actually putting out about 185-195 HP at the flywheel, and I am sure if you check the specs and compare, you will find it is putting out abit more torque then a standard 302/5.0 of the same time period. BTW, back in the late 60's and early 70's, in pickups, the 300 Was rated at 170 HP at the flywheel, and this was with 7.9:1 compression.

Ok that's what I thought, it's a little more than the specs since it's a 2002 Ford F-150



http://cliffordperformanceshop.com , is the website to go to for finding goodies for your 300 I-6.

Thanks I already had some info on them though. They have a lot of good stuff for straight6s.



They are very susceptable to even the most minor of modifications.
They are a very sturdy engine and will last quite long with good regular maintainance.

That's what I'm hoping, to be able to get it going with out to many mods that'll screw up the gas mileage that I bought it for in the 1st place.



With a 4 inch bore and 3.98 inch stroke,veing a nearly square engine, dont expect to be able to turn them the kind of RPM you would expect out of a V-8 of similar state of tune and displacement. But then you dont have to.
Rule of thumb. Given a 6 and an 8 of similar displacement and state of Tune, the 6 will produce 30-40% more torque than will the 8 cylinder.
Torque is the real game, not horsepower, as horsepower is mearly a mathmatical formula to convert Torque to something people can relate to.

That's what I'd always heard that a 6 would pull better than an 8 of about the same size.



Knowing the year and type of induction system you have currently would help a lot. That being said, if its a carbureted version, an aftermarket intake, with a 390-450 CFM, vacuum secondary 4 bbl, and a set of headers with high capacity exhaust, would do wonders for your 300. Clifford makes intakes, cams, and headers, as well as some more exotic parts for your 300, and Offenhauser makes a couple different manifolds.

As I said before I'm sorry for leaving out a lot of the helpful info that a person in the know would not have left out. It's a 2002 Ford F-150 w/EFI. I plan on new headers and a better exhaust as soon as I can afford it.



Recurving of your distributor is also an essential to getting the most out of your engine.[/QUOTE]

Ok I'll have to look into that. Some of this stuff I've read so far was familiar to me somewhat already, but not this with my limited knowledge.

Thanks Again,
GnrYmr
 
#9 ·
An F-150 Guy also!

Although clifford is the inline specialists, they come at a price.

Good news, you can buy everything elsewhere and save$$$$ alot.

Thanks, that's the best news I've seen so far, I'm on a very tight budget!



Any popular cam company has a camshaft for your engine, if low end grunt is what your after, the stock cam is fine.

Yep I'm lookin to get off the line with a good grunt. So I think I'll stay where I'm at.



Most all header companies will have something to offer, none are a direct bolt, all will require you plumb from the header to the existing exhaust pipe(s). Depending on application, you will have to notch the alternator bracket. If you have efi, there is a chance you will have to install an O2 bung and egr to header/exhaust manifold bung, depending on the brand/company, you use.

Efi exhaust manifolds aren't that bad, they consist of dual 3 to 1 manifolds, when in doubt, keep them if you have efi now or if you have a carb setup, consider them, as they are cheap if you look around.

If your carbed, Offenhauser intakes, sold by jegs, paw performance, summit racing, ebay, have an intake that will work and again, not cost an arm and a leg, as compared to clifford performance.

The real restriction is the head, if you can port or have that sucker ported, it will wake it up. The carbed head can accept a 1.94 intake valve easily.
The efi head, can but it will be shrouded badly, best bet with the efi head is the stock valves, if you must use larger valves, unshroud the valves and try and use more timing. As the stock efi head is a swirl/fast burn head and requires less timing than the carbed head to be efficient. You go changing the shape of the efi combustion chamber and you begin to work against its intended design, keep that in mind, also the efi heads are prone to cracking, some people have went through a few before they found a usable core. :)


Good luck[/QUOTE]

Thanks for the good luck, but I'll be digesting this for a while cause most of this is over my head? About the only thing I know about here is porting the head, which I want to do as soon as I can get the exhaust taken care of. Or should I do the heads 1st then the exhaust?


Thanks Again,
GnrYmr
 
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