SB to FE conversion?

[ztarum]

I'm getting close to ordering a Superformance and am trying to figure out what engine to use. Like most folks I would love a 427 SO or a 428, but also like most folks I'm not sure if that is in the budget. If I go with a small block to cut down on initial cost, how difficult would it be to convert to an FE down the road? Do the cars have significant physical differences, or is it as simple as changing the motor mounts and headers?

[John Martin]

I would suggest for you to do is ; first go with your dream of what you want under the hood . I did a 390 , then went to a 427 to get a little more power . Now I see what a small block turning 8-9k can behave like.

[jwoodard]

Changing from a small block to an FE in a Superformance is pretty straight forward. Different motor mounts and different headers is about all there is. As far as going from a 390 to either a 427 or 428, no problem. They are all FE's so motor mounts and headers are the same.

[BDHE]

Originally Posted by ztarum

I'm getting close to ordering a Superformance and am trying to figure out what engine to use. Like most folks I would love a 427 SO or a 428, but also like most folks I'm not sure if that is in the budget. If I go with a small block to cut down on initial cost, how difficult would it be to convert to an FE down the road? Do the cars have significant physical differences, or is it as simple as changing the motor mounts and headers?

Ztarum;

It's just my opinion -- owning a Cobra should be about satisfying a deep-seated, irrational need to own and drive what may be one of the most vicious, uncompromising pieces of American automotive hardware we can legally put a license plate on.

Having said that, you probably can guess what I'm going to say next. You really should consider waiting just a little longer and put your "dream" engine in there to start with (no compromise!). If you put something "else" in to begin with, you'll still have to pay for the other hardware at some point in the future -- or worse yet, NEVER get the other powerplant, and feel like you've settled for something less that your dream.

Bryon

[Gene Gorman]

Winter time is comming and Cobra prices go down during the winter. Think about looking for a used car with the engine you really want. You will find that you can get a nice used car with a 427 for less than you could buid a new small block car. I found one with a alum Shelby engine with only 970 miles on it for less than building a new one with a 342 engine.

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[purple panther]

dont do a cheap engine install. put in at least a bb crate motor or rr427 as for winter cobra pricing. i dont think the cobra market can get any more saturated . i would go used too. serious buyers market. i would like to know how many superformance are even being sold at 43,500?. i guess thats why they are selling used cars now.

[ou812545]

Other than price, I have heard that the bellhousing on the big blocks 390, 427, 428s hang low on the SPF's and bottom out often. Is this correct?

I am also in the market for a used SPF and waiting for the right car and price to come along. It appears that owners are still asking top dollar even in the winter months.

[Bill Wells]

should not be a problem bottoming out . i have 3-1/2 inch clearance under mine and have not bottomed out . i do go at a 45 degree angle over speed bumps and also when pulling into or out of steep driveway entrances- and I dodge road kill .

right car /right price - it will come along - always does as some are not in need of a quick sale and others on occasion are . just be ready to jump when you see it . also, prices asked are not indicative of final sales price either .

keep looking - cobra country, club cobra and ebay . bill.

[ou812545]

Bill,
Nice SPF with the Paxton, but I'm not sure what I like better, your cars or your garage (cars!). Very nice garage.

As for the clearance, is 3-1/2 inches common for the small blocks as well and did you cut or modify the bellhousing to get the 3-1/2 inches?

I'm on the hunt for the right SPF and have seen all kinds of claims ($19K in engine receipts, 600hp, etc...) with very few having any documents to back them up. I'm sure the right one will come along.

[Dwight]

ztarum,
you can install a 390 now and later swap it for a 428. Everything will fit, starter, headers, intake, carb, distributor, oil pan, water pump, etc. A bone stock 390 will have 275 to 300 rwhp. That will make a 2400 lb car fly. After you get use to flying and want more power. Get a 428 or build the 390 block. Lots of options.
Buy the book "High Perfromance Ford Engine Parts Interchange" by George Reid ISBN 1-884089-33-x $20 or $25
If you buy the correct block you can easily build a 427 or 428 motor.
Don't worry about the 390 pushing a Cobra. I've seen two or three 221 rwhp Cobra smoke fast cars at the red light.

Dwight

[ztarum]

Thanks all for the comments. I ended up going with a 351W, primarily to keep the costs down. It dyno'd at 465 HP (at the crank), which should make for around 300 RWHP. It should be plenty I suspect. I'm supposed to take delivery at the end of this week, so I'm pretty excited.

I still wouldn't rule out building a FE down the road, but I must say a weber set-up would be pretty cool even on the small block. I also just saw the pictures of the BDR with the supercharger. I think that was on a 302, but definitely a cool set-up.

[TerrysSPF]

Like others have mentioned, if you want to save some $$$ now then I would go with a 390 versus a small block. Then later on if you want to change to a 427 it will be much easier.

I think there are several other things you would need to change, besides the motor mounts and headers, if you went from a SB to an FE. Expansion tank, bellhousing, clutch, flywheel, throw out bearing, maybe the hydraulic clutch assembly, remote filter adapter, starter, etc........
I'm not sure about this, but you may even need a shorter drive shaft. (?)
There are a limited number of connection from the electrical system (guages, ignition, etc.) to the engine and they should be re-usable. But, IMO, it wouldn't be worth the hassle when you can build a nice 390 (and have the correct FE look) for the price of a SB.

[decooney]

There are a number of nice SPFs running around with budget built FE/390s in them. Truth is, if you can find a nice clean block and crank..., they look-sound-run and perform great on a car with street tires. Sort of a no-brainer combination if you ask me. Save the extra money and invest in some decent aluminum cylinder heads and a nice brand new carb, intake, distributor and MSD ignition setup and you'll be set for a long time of enjoyment. Good Luck.

[Bill Wells]

ou812545......re your bellhousing question . no mods on mine but i have seen some cut off/trimmed flat at the bottom for a little extra air space between it and the road .

your comments re high dollar engines - yep, lots have big bucks into them - you just need to decide on your usage and need and then decide if the big bucks are worth it for you, or is there a more basic similar hp/trq crate motor for a fraction of the price that will fit YOUR needs . to each their own - just remeber, the cheapest time to get the most hp is the first time ! new or used ! as once ya get accustomed to the car then most usually want MORE HP > bill

[lovehamr]

You might like this:

http://www.southernautomotiveengines.com/

Steve

[SantaFe66]

I built mine up from a roller I got that was done right. I found a cheap 390 and have been happy with that for several years. Buuuttttt.......now I have the need for more power (it's a disease). So, this winter I'm building either a 428 from the 390 or stroking it to 430 with a kit. Since I got the 390 engine for very reasonable money ($1K), I could afford to upgrade to bigger cubes. I looked around until I found a distressed owner that had blown his 428 and bought his Ebrock heads, Roller rockers, valve covers and numerous other slightly used goodies. I got a 428 crank for $200, had my rods rebuilt and now have two options to consider. Either way I go, with a stroked .040 over 390 that will be 430+ with the kit, or a std bore 428 (boring the 390 to 4.13, if the block sonics OK). I will have an FE motor in it with much more power than the 390.

Moral of this story is you have a lot of options with a good FE motor. I think it was my best decision to go with the big block up front. You certainly can do this with a good small block Ford motor too. Be patient and keep looking, the right thing will surface eventually. Be sure you know what you want first though. There is plenty of good info on this website and good people to ask questions of.

By the way, there are many other very good cars out there in addition to the Superformance so keep your options open. Go look at others before you decide. Most owners would likely take you for a ride too, so don't be afraid to ask.

Paul