IFS vs Straight Axle on my '40

I'm doing my first build, a nice, barnish 1940 Ford Fordor Deluxe, and I plan to make it my daily driver/ drive it everywhere/"Sure, we can take my car on this long- *** trip" car. Right now I'm trying to decide if I should run a straight axle or IFS (which I know is not super traditional, as the mantra of the HAMB states). I've been told that you can make a straight axle ride as nicely as IFS if you know what you're doing, but I'm not sure how much I believe it-- can a straight axle ride be cross country worthy? Price is a bit of a factor for me, too, but the pricing and research I've done seems to say that the difference ain't much.

Any advice from more experienced rodders? Is IFS a better ride, especially on potholed streets, etc.? If I ran IFS, it'd be hidden by my nice big fenders, so I don't think it would detract too much from my car's overall *** appeal... Throw in your two cents, HAMBers!

Thanks!

 

The argument for straight axle seems to be a winner. Why? Ever seen a semi-truck with independent suspension??

Seriously, for ultimate dependability, keep it simple!!! A straight axle has just about two moving parts - two spindles.

As to ride, you must lube the spring leaves, either wet (grease, using channels and a hollow pinch bolt) or dry, using Teflon, or other, similar linings. Otherwise each spring leaf will add it's own stiction, and given 7-9 leaves, you got yourself a load of stiction.

True, an independent suspension is technically 'better', but, really, better at what, and do you have the structure (frame, etc.) to maximize that 'better-ness'?? Not to mention - how hard do you intend to push a 70 year old Ford??

Cosmo

 

Imho, it's what you want...

Think hard about grafting an early 1st Gen Camaro/Nova type cars rear steer subframe under her or the next, 2nd Gen subframe that will give you front steer OR do your homework really good and use a solid axle.

pdq67

 

I have a straight axle on my 36 and drive it alot, drove it to work all week 20 plus miles one way each day and I do not notice a real difference between that and my new car as far as ride goes...
I have a posies spring and a stock 38 Ford axle.

Steering, and brakes are another story as for the comparison but the front end rides fine.

 

Ditto, unless you're going to put 400 ponies to it and chuck it into the corners leave it straight, your wallet will thank you.

 

Camaro clip a '40 Ford ??

Very Cool, Cut your car in 1/2 & make it a Rolling Abortion !

There are so many Aftermarket springs, Sway Bars, Axles, ETC to make it ride Better than 95% of the New **** at the Dealership.

I Personally would Get an Original axle & drop it, Rebuild EVERYTHING, Bolt on a set of Lincoln Brakes & DRIVE THE PISS OUT OF IT !

IFS is Over Rated in these Old Bombs, But thats MY PERSONL OPINION.

 

I have 430 ponies in mine, and its fine. I do have disk brakes however. I think it rides great. I do plan to buy a swaybar.

 

I cut a Mustang II front end off a `40 frame, then grafter a better stock `40 front
frame w/xmember on my coupe...It rides fine.

Tom

 

No, no, no don't even consider doing a Nova type subframe swap!
Too wide, nothing (fenders, radiator ect) will fit right plus you'll lose a bunch of resale value, nothing will turn a buyer of a pre war Ford off like a Nova clip.
All things being equal (i.e. both set up properly) IMHO there is no way a solid axle will drive as nice as an independent. If it did new cars would still have them! That said all my early Fords have dropped straight axles. Yes, they drive like a car with a straight axle but that's part of the charm for me. As far as being road worthy, they made trips across country when they were new and the roads were a lot worse then they are today. Just have to remember it's not going to handle like a sports car we you hit the winding roads and drive it accordingly.

 

Run the axle……you can always butcher it later

 

Succinctly put .....................

 

As stated above, the axle provides a decent ride in a forty sedan. If you look at most IFS's on 40's the owners will tell you how much better they ride than the old axle they threw away. Do yourself a favor and find a buddy who has a 40 with a IFS and go for a ride. I think you will be impressed with the steering ease and corning but the ride IMHO is not that much softer. I personally don't like to cut up an old 40 but if you can... do it.

 

Straight axle. My '38 Sedan has a really nice ride with the original straight axle. Just add some tube style shocks and you won't be disappointed.

 

DO NOT EVEN THINK ABOUT IT.....
as mentioned earlier, find someone with an IFS installed and ask them to take you for a ride maybe let you drive, then make your decision...BUT...

whatever you do...do NOT by a chinese knockoff MII IFS, Spend some extra dough and get a Heidt's, or TCI, trust me you will wish you did if you buy one of the chinese knockoff's, you dont have to look at them too hard to see why they are "cheap"

 

I have a dropped straight axle/buggy spring set up on mine and honestly it rides and drives great. I used good quality parts and took my time to get everything set up right and it paid off. I drive it on long road trips regularly.

Personally, in my opinion if you're building a traditional rod, keep it traditional. If you want a street rod, do whatever you want, but don't expect it to be considered traditional.

Ultimately, its your car, build it the way you know you'll be happiest. Your opinion is really the one that matters.

 

Hell no, do the MII you will be glad you did.Ch***ie engineering is a good easy way to go more $ but not that much more if your going to split the wish bones and do a drop axle and a disc brake the money is about the same.Ch***ie kit bolts in you dont even have to weld it if you don t want to.Grind some rivetts knock em out holes all line up piece of cake.Put under my 36 had one with power in my 40 it drove sweet.Had straight axles under a roadster and a 3 window they were good too had a 56 f100 with a drop axle and a power slave cyl on it it drove really good but none compared with my 40 power MII

 

36 chas engineering stock control arms,big disc brake conversion,dropped spindles

 

I have 3 40 fordtwon with mustang (one bolt in one weld in) and a coupe with a dropped axle and a vega box

I'd personally worry less about "ride" and more about brakes
either option put the biggest best brakes on that are available

 

For the love of god don't even think of a camaro clip!!! The eighties are done once and for all! You can make a straight axle ride and even handle very nicely on these cars. Sway bars and slightly flatter but still supple springs, plus a good pair of shocks ( I'm convinced Bilstein is automotive drugs) can make for a very comfortable suspension that still can stick with the best of them. That said however, if ultimate tradition isn't the goal, I would still put a Mustang 11 in it. The poster above me made a very valid point about using quality goods, as important is using a kit that keeps stock geometry intact. This as important as any thing, because allot of the weird little "Mustang II" hiccups that you occasionally hear about are either aftermarket modifications to make a particular kit fit something, or improper installation. Elpolacko, one of the regulars here on the H.A.M.B. has compiled allot of do's and don'ts with Mustang II front ends and they can be seen on his web sight at www.industrialch***isinc.com. I recommend it as necessary reading before setting this type of front end up. I have put well in excess of 200,000 mi. on my '48 Plymouth with a MustangII under it, and wouldn't trade it for the world. A quick p.s. to this would be power steering or not. My preference has always been a big factory forties steering wheel and a manual rack, small later type wheel go with power.

 

There is something to be said for either setup. However, about two years ago I built a '47 Ford coupe and used the original straight axle but I made substantial changes to the springs/shocks on it. And I added disc brakes and a much heavier antiroll bar. The result was a quite nice riding and handling vehicle.

In my case I used a coil over setup in place of a leaf spring, but I am not advocating that in your case, as it was a lot of work and kind of an experiment. But, using as low friction a spring as possible is one element that is important as indicated by a previous poster. Also, the install of a good quality tube shock, probably not 'gas filled', as they tend to be a little 'harsh' IMO, and the aforementioned heavier anti-roll ('sway'). I installed a Speedway front disc kit that utilized F100/150 12" discs and big GM '71/'76 calipers and no booster was needed.

One of the best things you can do for a good ride is to be very conscious of keeping 'unsprung' weight to a minimum. Ride quality is determined as much, if not more, by the ratio of sprung to unsprung weight than by style of suspesion. That means wheels, tires, brake ***emblies (in that case, DON'T use the heavy F100 brakes mentioned above lol) should be kept as light as possible.

If you choose the independent route, Ch***is Engineering's bolt in independent unit would be a good one to check into. In any case..........best wishes

Ray

 

A customer of mine put a deluxe Fatman Must II in his immaculate '40 pickup. Power rack and disc brakes. He had me drive it, I felt like a fat man on a tricucle. Over-center, top heavy, touchy oversteer tendencies! I told him "Yes, the ride is very soft," and it was. But it felt like I was driving on bicycle tires 2 feet apart, at the low side of ruts.
He had a potential buyer, and the last thing the guy said was, "Gonna have to find a replacement frame..."
Hey, why the concern? Some jokers are putting '40s on Chevy S10 frames! I say "Go Gl*** '40 body on a mediocre '70s frame!" Think of the '40 you could have...

 

Would have to think this MMII setup was totally "out of tune".......I have driven MMII equipped late 30's up vehicles that drive very well. But tires, wheels, alignment and steering rack/pump pressure choices all have a bearing on results. Even the very best engineered factory setups drive poorly when not dialed in.

Nor abandoning my own recommendation (above) about straight axle use, but the MMII is better than represented here.

Ray

 

Which is exactly what I meant when I talked in my previous post about buying quality and proper geometry. I try really hard not to mention brand names when I post stuff, but that brand is one of the biggest offenders. Usually severely compromised geometry, lack of anti dive properties, low quality build, I can go on but I won't. Top that with just flat not dialing stuff in as said in the previous post, and you've got a recipe for disaster. Take a look at Elpolacko's websight before making a purchase and do some general knowledge learning and it will go a long way.

 

About 10 years ago I had two 1940 Ford coupes. One ( a standard businessman coupe ) with a dropped straight axle and one ( a DeLuxe Opera coupe ) with a Mustang II. I actually preferred the straight axle car.
It rode and drove as well or better than the IFS equipped coupe. I sold the IFS coupe and kept the straight axle coupe for 5 or 6 more years.

The IFS coupe did stop BETTER ... because of the disc brakes

 

have built 6 with dropped axle, large sway bars ,bilstien shocks, 525 boxs and disc brakes--look right, handle and ride fine and stop and steer well-wife has driven current one when I had a few too many and said it drives fine and is easy to steer and stop-works for me--but have heard good things about the CE bolt-in independant setup--currently doing another coupe--same as the rest-just works for me

 

If you wanted IFS you should build a Mopar from the same vintage . Even master delux chevs had it (39 -40 etc). A 40 Ford without a straight axle is like an ungly blonde. It just aint right son. Not somethin ya everwanna see.
Don

 

My Dad's '40 has a MII kit, I believe Heidi's. It rides and handles fine, but it isn't much better than the '37 we had with an axle.

So with that said I wouldn't change a car from an axle to IFS, but that wouldn't stop me from buying one with one. As mentioned earlier, as long as it is safely done.

As far as traditional goes, on full fendered cars, if you are low enough no one should be able to see it.

 

IFS ?? Just say no.

Bob

 

Won't work unless you want your skinny 5" rims sticking 5" outside your front fenders. Even the Mustang II front end people sell 5/8" narrower A arms to fit the narrow front ends of the 40 Fords.

 

I prefer a straight axle in anything that's being built with a "hot rod" vibe and that includes fat fenders. However, when your building a car and intend to put a lot of miles on it there is something to be said for an IFS. If I were to do another with IFS I'd go with the Ch***is Engineering setup as they have incorporated an adjustable ride height feature that lets you fine tune stance without a lot of h***le. Roadstar on here built one of the nicest '40 coupes I've seen with a Ch***is Engineering independent so maybe PMing him will get you some good input.

Frank