Fe 390+ ?

[KevinW]

Im planning on an FE +toploader engine/trans for my new project (just hoping for $1.70 on the exchange rate before ordering). I dont have the budget to go for a 427 or even a 428, so its looking like a 390-based block. im not looking for mega-hp - 400+ horses, similar torque will do me fine.

I saw on another recent post a suggestion that a 427 crank could be used in a 390 block to give the sacred '427' displacement, whch is kindof appealing.

as there are only a few cob reps runnning around with FEs in the UK, wondering what the pros and cons of FE390, FE 390 stroked to 406 or even 427. specifically:

are there any issues with using the big crank? special pistons needed??
Does it need a particular cam?
how does this handle compared to say a 390 overbored to, say, 406?

what is the upgrade cost compared to say an FE390/406?

Finally, and I hate to mention it, (but at >$8 a gallon in the UK, it nags at my wallet)
how much might it drop the mpg going from 406 to 427?
- realise this is dependent on the juice pedal, but using say similar driving style, %-age wise.

thanks,
Kevin

[blykins]

A 427 crankshaft and a 390 crankshaft are the same stroke. So if you use a 427 crank in a 390 block, you have a ......390.

Depending on your budget, you can either just use a factory 390 block, crank, rods, new pistons, etc., and have your 400hp.

For a little more money, you can use a new Scat stroker crank, rods, pistons, etc., and have about 445ci.

None of these cars really get good gas mileage at all, and you probably wouldn't notice much difference between the engine sizes that you have mentioned.

You might wanna tell us how much you wanna spend, and then we can guide you with that.

[RICK LAKE]

KevinW Kevin find a good core 390 and stroke the thing to 4.25 for a 445 size. Car craft had a buildup about 1 year ago with Barry R. buy a block and buy his kit that is balanced for a small added cost. Have it shipped to you. It's a basic drop in kit. Mic the mains and rods and cut the rings to size. Camshaft would be something in the .530" with 112 LSA. Forget about HP. Build a nice torque motor with 450-500 pounds. Have some pocket port cleaning of the heads and gasket matching of the ports. A small carb in the 650-700 cfm's. If you have a little money left over, get aluminum heads and intake. Barry and KCR both sell a nice set of heads for a great price. Stage II. Trans gearing and rearend gearing is also very important. You need to give this some thought. 4 spd,5spd, or 6spd trans, get a first gear no higher than a 2.80 for the car. Anything higher you will never use it, unless you are in parades. 3.31 or low in rearend gears for a street car. Higher if you are going to drag race it or road race it.
IMO the most important thing, have the oiling system worked over, HVHP oil pump with a 80# spring. .080 holley jets for the heads to control oil. 6 quart oil pan min. A canton 7 quart for cobra would be alot better. RPM limit of 6,000 or 500 rpms past the limit of the camshaft range in the catalog. 6,200 max. Heavy bottom end swinging around in that block. Write a plan for the car building and stay with it. Check out the FE forum also for good info. Good luck with the build. Rick L.

[undy]

Kevin,

I believe that Scat's 4.125 stroke crank with a small over-bore will give you that magic "427" you're looking for with a 390 block. You will need purpose built stroker pistons (readily available) and a set of Scat or other aftermarket rods. Most of the aftermarket crank and rod mfrs use Chevy BB rod/rod bearings which is a much stouter design over the FE rods/bearings.

You can get the rotating assembly from any one of our board vendors, Blykins, Keith Craft or George Anderson + others. I would suggest you get the whole deal at once, crank, rods, bearings, rings, harmonic balancer and flywheel from the same dealer. I would also offer a suggestion on having everything internally balanced by the vendor too prior to shipment.

Dave

[KevinW]

great info guys - thanks.

ok, complete homer simpson dunce on the stroke thing, so maybe i meant overbored.

i know guys runnning FEs (390/406, 427S/O, 428 and 390/454) in cob reps in the UK, all have used http://www.southernautomotiveengines.com/ with no major problems, so ive been thinking about their 406 FE which looks like very good value for money, coupled to their toploader option (with the small input shaft and 28 spline output) as a turnkey solution. It took me more years than i want to admit to get the last car on the road (w/e only in the garage, job changes/house moves/kid/etc etc), and i want to do drive this one round the Nurburgring in less than 2 years, and without a bank loan.

the rear end is a jag XJ6 with a 2.88 diff.

cheers, Kevin

[Clois Harlan]

Ther is a guy here in the States in Southern Illinois that builds a nice package with a Complete 390 tko 600 bell housing clutch etc (for around $10K). It is a nice dependable torque filled engine that will redline about 6K. His name is Larry (Lumpy) L.....? :Can't speel his last name.

Performance Motor Sports Systems Inc, Greenville IL 62246 ...Tel: 618-664-4767.

I have seen several of his 390 engines and they are very nice engines that are built well enough to track but intended for every day driving. Very dependable.

Clois Harlan

[trularin]

Kevin, are you going to build the engine or are you looking to buy the engine ready to rock?

Stock pulls ( engines pulled from cars and trucks ) can be had for $100.

With crating and shipping, you could have a basic engine at your door for maybe $700.

Share with us a bit more of your plan and what you want to do so we can steer you in a completely different direction.

I have a 360 FE you can bore to the 406 neighborhood for $100.

[convincor]

Here's the CarCraft build mensioned above as well as one HotRod did.

http://www.carcraft.com/techarticles..._fe/index.html

http://www.hotrod.com/webonly_january/index.html

[rustyBob]

Kevin....check out the build Edelbrock did, I built my FE the same way and it has plenty of torque and horse power for a Cobra and the cost of the build was afforadable.

[kurtmart]

Yo Kevin. You mentioned a toploader. You might consider a Tremec 5 speed. The "tall" 5th gear will give you much better gas mileage at freeway or autobahn speeds. I get 22+ mpg at 85 mph turning 2100 rpm with my 428.

[Excaliber]

This of course assumes 85 mph is a reasonable speed for cruising without risk of a speeding ticket. When going with a 5 speed the rear gear ratio, cam profile and 5th gear ratio need to be considered to achieve a reasonable cruise rpm at your expected cruise mph.

High rear gear, like a 3:31 Jaguar? A .6 OD wouldn't be the best choice, .8 would perform better at lower mph.

[KevinW]

all good stuff guys - thanks.
my jag diff is the 2.88 variety that was on the V12 cars, because i decided toploader on the original, so toploader for me. no turning back now - my chassis has mounts for FE+toploader welded on. im aware of the advantages of the 5th gear, but i think people usually have a 3.3+ diff when they fit these 'boxes? so its kind of swings and roundabouts? overall im hoping for only a smallish increase in rpm when im cruising compared to say TKO and shorter diff. hopefully the secondaries wont be open much then. If caught, in the uk, 85mph will get you 3-6 points added on to your licence (12 points =banned for a year). but plenty of us touch these speeds for short periods official national speed limit = 70mph.

yeh, i was mainly thinking about buying turn-key for the engine if i can - there is less local FE knowledge/resources in the UK (compared to say SBF/SBC), and ive read the warnings about needing to know what you;re doing with these engines - ive never rebuilt an engine.

[Excaliber]

A 2.8 rear gear with the top loader is a nice combination! Man that would be a disaster with a 5th gear OD in the .6 range and not so good even with a .8 range. You done good.

[Tom Kirkham]

A 390 block with a 428 crank is a 410. 410s were available from Mercury in their pick ups. With a 2.88 gear set you will have to use a wide ratio toploader. The close ratio toploader will make burning up clutches a very real problem.

[convincor]

410's were used in the full size Mercs (66-67 only)like the Park Lane and the Marauder.
http://en.wikipedia.org/wiki/Mercury_Marauder
http://en.wikipedia.org/wiki/Mercury_Park_Lane
Not the P/U's. http://www.mercurypickup.com/truck_data.htm

[Argess]

I would liked to have had a 427 in my Cobra, but Sideoilers are hard to find and very expensive. Additionally, a center oiler 427 looks like a 428, but has the problem all 427s have.....max recommended overbore is 0.030", and most will already have this done, so that's not good.

The other original big block engine was the 428 and are easier to find. I did up an overbored 410 (to the point I call it a 428), but pistons arn't the easiest or cheapest to find. A full overbore to a 428 is risky with most 390s due to cylinder wall thickness, however some 390s, especially later year 390s do have thicker cylinder walls allowing for a 428 overbore.

A 390 with headers, carb and especially a cam change can easily be made more powerful than a stock 428, and looks the same from the outside.

The thing about horsepower, is that it's work done over time. It's hard to develop full horsepower from any of these engines due to the car being so light, except at very high speeds, which is extremely unsafe, not to mention illegal on public roads, so as someone mentioned above, a nice torquey engine is the way to go, and that is mostly dictated by camshaft selection (although a 428 crank obviously helps).

As far as gas mileage, don't worry about it. Not only is gas the cheapest expense of owning a car (compared to purchase price, yearly registration, insurance, etc.) it is unlikely that you will put high mileage on a hobby car, although some peple do I guess. So your total gas expense per year may not be a lot.

Most of the fun is in second gear shifting to third....but gas mileage will be bad when you accelerate hard....like Niagra Falls in the carb(s). But highway cruising isn't bad. Light load, better fuel economy.

I find taking the Cobra for a drive a major event. I have to walk 100 yards to my garage, open the garage door, start the engine and back out. Then I have to keep it idling for a few minutes so it won't stall (no choke) and then drive it at least 5 miles until the oil temp starts to come up before I dare put my foot into it. Once back in the garage, I like to wait until the electric fan automatically shuts off before I leave, not to mention opening the hood to check for leaks (like gasoline).

Almost embarassing, I ordered my kit in 93, picked it up in 94, got it done and on the road in 96, and it just turned over 5000 miles a few days ago. Lazy? Maybe ...OK, yes I am. However, I must admit, I enjoyed the building more than driving it. I used to be embarrassed by the looks I got, but finally realized they are looking at the car, not me. Although one time, I was cruising past the local kids hangout by the Liquor Store at the mall one Saturday evening, and one young fellow hollered "Hey, Old Man!" at me. Guess the gray hair prompted that. My GF sitting next to me had a coniption fit laughing so hard.

[FatBoy]

Originally Posted by KevinW

all good stuff guys - thanks.
my jag diff is the 2.88 variety that was on the V12 cars, because i decided toploader on the original, so toploader for me. no turning back now - my chassis has mounts for FE+toploader welded on. im aware of the advantages of the 5th gear, but i think people usually have a 3.3+ diff when they fit these 'boxes? so its kind of swings and roundabouts? overall im hoping for only a smallish increase in rpm when im cruising compared to say TKO and shorter diff. hopefully the secondaries wont be open much then. If caught, in the uk, 85mph will get you 3-6 points added on to your licence (12 points =banned for a year). but plenty of us touch these speeds for short periods official national speed limit = 70mph.

yeh, i was mainly thinking about buying turn-key for the engine if i can - there is less local FE knowledge/resources in the UK (compared to say SBF/SBC), and ive read the warnings about needing to know what you;re doing with these engines - ive never rebuilt an engine.

Hi Kevin,

I have a close-ratio toploader with a 2.88 read end in mine and it works fine. It may have a slight impact on the acceleration times, but not so's you'd notice. In any case, once the tyres are spinning, what's the point of spinning them faster?
Mine cruises at around 85mph at 3,000rpm, which is fine.
If you're ever in my neck of the woods, let me know and we can meet up and I'll take you for a run so that you can see what it feels like.

Paul

[westcott cobra]

Hi Kevin,

i'm going with a 2.88 and Tremek 3550 with a low 0.68 fifth and will keep this setup for my upcomming FE replacing the Cleveland in my Crendon.

Revs are 2000 at 150Km/h this is perfect speed for long highway distance drives and if you shift down to 1:1 fourth, you have the "normal" 4 speed setup as you will have with the Toploader.

Westcott