What Makes Ford Intakes Bad?

[colnago]

I've read that Ford 4BBL intakes do not flow well, so if you want performance, you need to upgrade the intake (along with exhaust, but that's another topic for another time). So that got me wondering, what makes a Ford intake bad? Narrow runners? Poor port matching? Bad angles? Other?

Joseph

[markguiver]

https://www.diyford.com/ford-fe-engine- ... ate-guide/ . Here's a good read for you.
Mark.

[colnago]

I'd read that article before, and it was an enjoyable reread this evening, but it didn't really tell me why the Ford Intakes aren't well-regarded. My truck hits 3000RPM at 65MPH, so it's never going to see higher RPMs than that; if this is the case, would I see any benefits to swapping an Edelbrock Performer RPM onto the engine? Why or why not? Maybe I can find my answers in "Thee Great Intake Comparo."

Joseph

[Jacksdad]

Wrong manifold for your application. You need something that matches your intended use, which sounds like a work horse with as much low end torque as as possible. A regular Performer would be a better choice. Not much more power, but prettier and lighter.

Stay small on the carb too. If that really is your intended rev range, don't go overboard and strangle it, but don't go bigger than 550-600 cfm.

[Ranchero50]

Yep, you really need something like the cross ram off the Dodge 413 wedges. Runners that were @ 24" long will make amazing torque.

[colnago]

Currently, I have a Ford 4BBL iron "T" intake from an early '70s truck. I still have the 'S' manifold I used to run. I've heard that the Edelbrock Performer (not the Performer RPM) was designed after the Ford Intakes. This is just a daily driver, so I don't need to go bananas with anything. I guess my main question is, if I keep it under 3000RPM, would I benefit from buying anything different? Can I mod the 'S' or 'T' intakes to perform better, and if I can, how?

On the carb, I have an Edelbrock 1405, with inserts to convert the mains to 500CFM, and rejetted to match. It's sitting atop a 1" spacer. Should I go taller? Shorter?

On the exhaust side, I just have the factory "logs." I've been thinking about headers, but again, I'm not sure if I would see anything just puttering around town. Current exhaust is single 2", with a 'Y' tube to combine on the passenger side.

I'm also thinking about getting new timing gears that would allow me to advance the camshaft by 4 degrees. And maybe thinner head gaskets to increase the compression ratio a tad.

I don't want to race. I don't want to move a mountain. I just want to bump the mileage a tad. Currently, it's a bit of a toy, so Mama gives me a long leash (she'll draw the line at me getting a blonde copilot, though). I know that, for the money, it's cheaper to buy a used Mustang, but I know that I can get more out of the old girl. Besides, it's a pride thing. At work, I'm the old guy in the old truck (I was born in '61, so I really want a '61 F100).

Joseph

[tnlprt]

Currently, I have a Ford 4BBL iron "T" intake from an early '70s truck. I still have the 'S' manifold I used to run. I've heard that the Edelbrock Performer (not the Performer RPM) was designed after the Ford Intakes. This is just a daily driver, so I don't need to go bananas with anything. I guess my main question is, if I keep it under 3000RPM, would I benefit from buying anything different? Can I mod the 'S' or 'T' intakes to perform better, and if I can, how?

On the carb, I have an Edelbrock 1405, with inserts to convert the mains to 500CFM, and rejetted to match. It's sitting atop a 1" spacer. Should I go taller? Shorter?

On the exhaust side, I just have the factory "logs." I've been thinking about headers, but again, I'm not sure if I would see anything just puttering around town. Current exhaust is single 2", with a 'Y' tube to combine on the passenger side.

I'm also thinking about getting new timing gears that would allow me to advance the camshaft by 4 degrees. And maybe thinner head gaskets to increase the compression ratio a tad.

I don't want to race. I don't want to move a mountain. I just want to bump the mileage a tad. Currently, it's a bit of a toy, so Mama gives me a long leash (she'll draw the line at me getting a blonde copilot, though). I know that, for the money, it's cheaper to buy a used Mustang, but I know that I can get more out of the old girl. Besides, it's a pride thing. At work, I'm the old guy in the old truck (I was born in '61, so I really want a '61 F100).

Joseph

Get rid of the crap carb

You took a carb that is proven to hurt HP and made it worse

It has been stated many times in replies to your posts to get rid of the factory exhaust manifolds and put on a set of headers....Biggest improvement you will see for the dollars spent

Why would you assume you need to advance the cam if you have not degreed it

[colnago]

Tnlprt,

Thanks for your helpful input. You are an inspiration to us all.

Joseph

[DuckRyder]

... maybe we could just stipulate that the exhaust has been covered...

...cam too... on the timing set a quality one that is adjustable would be a good thing. Id install it “straight up” in most cases.

AFAIK no common factory intake of any make has a stellar reputation baring the special stuff such as Jamie mentioned of course. Edelbrock performer intakes are certified as stock replacements thats how they get CARB approval. IMO your unlikely to gain enough to warrant the expense if you already have a factory 4V intake. Of course for those changing it in the truck the weight alone may be worth it.

[Jacksdad]

I know you want to build the best motor for your application, but don't sweat the small details too much or you'll never be happy. It sounds like you want a stump puller that gets better gas mileage, rather than squeezing every last hp out of your combination. Instead of resorting to racer's tricks like advancing the cam to try to make it a better fit, I would buy one that is already engineered to suit your driving style and run it. Something like Comp Cams # CL33-221-3 would be an ideal fit for a basically stock FE with compression in the 8:1 to 9:1 range. It taps out at 4800rpm, but pulls hard from idle. It's pretty conservative on lift and duration, but it'll give you more low end grunt while improving your gas mileage.

Yes, definitely get headers if you're trying to make the motor more efficient. If you don't want the hassle of full headers, go with a set of shorties. Although long tubes give you a little more low end power, shorty headers are still a lot better than the stock cast iron manifolds. Depends on your budget, and how much fun you want to have installing them. We have a ton of space under the hood compared to a passenger car, so you might get lucky with a set of cheap eBay shorties.

https://www.summitracing.com/parts/cca- ... /overview/

[Ranchero50]

I find a big bore 390 2100 and stick it on an adapter plate and maybe a set of 1 5/8 headers if you don't mind fighting cooked starters. I'd also recommend doing a 4bt swap before any of that if you are looking for efficiency. I like my 6bt but it was a PITA to install.

Cam is a waste of time until you bump the compression, worrying about the intake or exhaust fall in the same category. I will say that every timing chain I've installed has needed to be fully advanced to stay straight up after breaking in. Advanced gives torque, straight up ends up retarded.
Retarded is well, retarded.

To me every Ford V8 engine gets a high volume oil pump, an advanced roller timing chain and Total Seal gapless rings.

[colnago]

I think I'm falling into the "as long as I'm at it" sinkhole. If I put in thinner head gaskets to bump up compression, I have to take off the intake and water pump. As long as those are off, I'll get a new timing set and degree the cam. As long as the intake is off ...

I think the biggest bang for the buck is headers, but I don't know how much benefit I'll see if I keep it under 3000RPM. Decisions, decisions. It's only time and money.

Joseph

[Ranchero50]

Have you ever really defined what you want out of your truck? I seem to remember a bunch of random question threads that never defined the goal. They went sideways once you disagreed with the answers. This one is a good example. You seem to be asking for advice for your build in a bass ackwards way. Without knowing what you want and having a plan to get there you'll never reach your goal.

Define its intended use and duty along with the driveline parts in play now along with your plans and we'll go from there.

[colnago]

Daily driver. No racing. Dump runs and rare tows. Low RPM. And a moving classroom.

Joseph

[DuckRyder]

By a moving classroom do you mean that you want to learn things about it working on it...?

I’m curious why a Comp 252H is a recommendation over something like the Crane 901? If I’m being honest I think it is not a very good choice. Will it run ok? Sure - it is too small to run bad as long as the DCR isn’t so high it disintegrates a piston, but something with 10-15 degrees more exhaust duration than intake would work better IMO. Comps HE and MAG lines are some of the oldest grinds they offer they were out before I graduated high school when Comp was called “Competition Cams” and Racing Head Service built crate motors... I’d lean towards more modern cam profiles...

So from previous threads we know you’re considering pistons, cams and intakes, from the ill fated cam thread I think its fair to say the exhaust is a well beaten dead horse... It may in fact just be a damp spot at this point so....

I’ll tell you what I would do if I was going to put a motor in a truck for the kind of use you are talking about - and wasn’t really wanting to hot rod it around.

I’m going to assume you already have a 390 crank and rods as well as a factory 4bbl intake...

I’d put a set of pistons that would get me 9:1ish compression in it. I’d pick me a cam with more duration and lift on the exhaust than intake and I’d get everything that matched it, springs, retainers, lifters. I’d put a true roller timing set in it, have it all machined nicely and put it together checking and double checking everything... I’d degree the cam, cc the heads, cc the pistons the whole shooting match. I'd put the factory intake on it, some nice rockers (getting harder to find) and put some headers, 2.5 inch duals and Holley Sniper on top of an open spacer. Then I’d drive it. if the 3000 RPM cruise turned out to be a huge issue I’d change the gear....

I realize none of this actually answers your question about why exactly the factory intakes are “bad” but IMO they really aren’t that bad for what you are wanting to do if you already have one for a 4V.