How does an FE 390 compare to a Chevy 454?

[robroy]

Hi!

My work/utility truck is a 1986 Chevy C20 454, and while driving it today I got to wondering how the FE 390 compares to it.

How would somebody experienced with both engines compare their characteristics? I know this is an open ended question, but do any valid generalizations come to mind?

Thanks!
-Robroy

[SteveC]

with a search on the interent stock 454

mind you this may not be the most accurate and i am by no means a expert or all that experianced

454

The big-block was expanded again for 1970 to 454 cubic inches (7.4 L) with a 4.251 in (108 mm) bore and 4 in (102 mm) stroke. The 1970 Chevy Corvette LS5 version of this engine produced 390 hp (291 kW) and 500 ft·lbf (678 N·m), and the LS6 engine was rated at 450 hp (336 kW). It has been suggested that the LS6 was substantially underrated and actually produced well over 500 horsepower (370 kW) as delivered from the factory, although there is no empirical evidence to support this claim. Indeed, the AHRA ASA Class record holding Chevelle LS6 for the 1970 season posted a record setting trap speed of 106.76 MPH "1970 ASA LS6 454 Records", which suggests something on the order of 370 "as installed" (SAE Net) HP for a 3,900 pounds (1,800 kg) car and driver combination.

A 465 hp (347 kW) and 490 lb·ft (664 N·m) version of the 454, dubbed LS7 was also designed but never went to production. However, a handful of LS7 intake manifolds were produced and sold by a handful of Chevy dealers as performance parts. The LS7 was later offered as a crate engine from GM and advertised at 500 hp (370 kW).

Power began falling off after 1970, with the 1971 LS5 producing 365 hp (272 kW) and 465 lb·ft (630 N·m), and the LS6 option coming in at 425 hp (317 kW) and 475 lb·ft (644 N·m). Only the LS5 remained in 1972, when SAE net power ratings and the move towards emission compliance resulted in to 270 hp (201 kW) and 390 lb·ft (529 N·m). The 1973 LS4 produced 275 hp (205 kW) and 390 lb·ft (529 N·m), with 5 hp (4 kW) and 10 lb·ft (14 N·m) gone the following year. Hardened valve seats helped allow these engines to last much longer than the earlier versions, even without the protection previously provided by lead from fuel. 1974 was the last year of the 454 in the Corvette though the Chevelle offered it in the first 1/2 of the 1975 model year. It was also available in the full size Impala/Caprice until model year 1976.

GM continued to use the 7.4 L (454 cu in) in their truck line, introducing a new Vortec 7400 version in 1996. GM also introduced the 7.4 L 454 EFI in 1990 (known as the GEN V; the previous generation was known as the Mark IV produced between 1965-90; the GEN prefix was used since Ford Motor Company owns the Mark V naming rights since it was used on a Lincoln automobile between 1977-79), which was electronically fuel injected giving more power and torque. Instead of the regular 290 hp (220 kW), the 454 EFI version cranked out 365 hp (272 kW) and 415 lb·ft (563 N·m) of torque. The 454 EFI power ratings were very similar to the early 1970s LS5 454, which was found in early 1970s corvettes and chevelles. The 7.4 L 454 EFI was found on GM 3500 trucks throughout the early 1990s until replaced with the Vortec 7400 (GEN VI) in 1996.



ford 390

The 390, with 389.6 cu in (6.4 L) true displacement, had a bore of 4.05 inches (102.87 mm) and stroke of 3.78 inches (96.01 mm). It was the most common FE engine in later applications, used in many Ford cars as the standard engine as well as in many trucks. It was a popular high-performance engine[18]; although not as powerful as the 427 and 428 models, it provided good performance, particularly in the lighter weight vehicles. The 390 cu in (6.4 L) 2v is rated at 265 bhp (197.6 kW) @ 4,100 rpm

# 2V

* 8.9:1 — 250 horsepower (190 kW) at 4400 rpm and 378 lb·ft (512 N·m) at 2400 rpm
o 1963-1965 Mercury
* 9.4:1 — 266 horsepower (198 kW) at 4600 rpm and 378 lb·ft (512 N·m) at 2400 rpm
o 1964-1965 Mercury
* 9.5:1 — 275 horsepower (205 kW) at 4400 rpm and 401 lb·ft (544 N·m) at 2600 rpm
o 1966 Ford
o 1966 Ford Fairlane
o 1966 Mercury
o 1966 Mercury Comet
* 9.5:1 — 270 horsepower (200 kW) at 4400 rpm and 401 lb·ft (544 N·m) at 2600 rpm
o 1967 Ford
o 1967-1968 Ford Fairlane
o 1967 Mercury
o 1967 Mercury Comet
o 1968 Ford Mustang
o 1968 Mercury Cyclone GT
o 1968 Mercury Cougar GT
* 10.5:1 — 280 horsepower (210 kW) at 4600 rpm and 427 lb·ft (579 N·m) at 2800 rpm
o 1968 Ford
o 1969 Mercury
* 9.5:1 — 265 horsepower (198 kW) at 4400 rpm and 401 lb·ft (544 N·m) at 2600 rpm
o 1968 Ford Fairlane
o 1968 Ford Torino
o 1968-1970 Ford
o 1968-1970 Mercury
* 8.6:1 — 255 horsepower (190 kW) at 4400 rpm and 376 lb·ft (510 N·m) at 2600 rpm
o 1968-1971 Trucks [19]
* 9:1 — 255 horsepower (190 kW) at 4400 rpm and 376 lb·ft (510 N·m) at 2600 rpm
o 1971 Ford, Mercury
* 8.6:1 — 201 horsepower (150 kW) net at 4000 rpm and376 lb·ft (510 N·m) at 2600 rpm
o 1972-1975 Trucks

[LANCE65]

my 454 crewcab will walk all over my '71 F250 390.
-Lance

[My427stang]

454 has a better head design, bigger bore, bigger stroke. However, they can be fussy on fuel because quench isnt that good and the large chamber doesnt like flame travel too well.

The lower end on a 390 is much less troublesome, when a Rat motor Chevy blows, it almost always takes all the rods and crank with it, I have seen a ton of them let go at high power levels.

Bottom line though, the 454 has a much higher power potential than a 390

[robroy]

Thanks for the replies guys!

My 454 in my 1986 Chevy C20 is rated at around 250 HP. As I understand it it's one of the most "Smogged out" years.

One thing I notice about the 454, and this could be caused in part by the transmission, is how amazingly smooth and powerful it feels at low RPM. Back when I had my 360 in #50 it never felt like it had that tremendous, super mellow low end power. I also notice that the 454 does absolutely nothing when I floor it and try to rev it up--it does everything it's going to do below around 2,500 RPM.

What I'm really interested in is a comparison between its characteristics and #50's new engine, which is a 436HP/463ft/lbs @ 4,000 RPM 390 from Proformance Unlimited. I wonder if it will have that same massive, mellow way of starting out from stop lights, or if it will be more of a motor to wind up to higher RPMs. I'm guessing that it'll come to life above 2,000 RPM, since that's the intake and the intent in general, but I'm curious what it will be like below 2,000 RPM also.

Well I know there are lots of differences between these engines and my question is therefore a little goofy, but I appreciate the responses!

-Robroy

[My427stang]

Well, heres the comparison IMO

Look at rear axle ratio multiplied times 1st and second gear ratios in both trucks. That should tell you how "free" it revs off the line

Second, I would expect that the 390 in a drag race will obliterate the stock 454, hp wins drag races and you'll have more, but off idle the 454 will still pull a little stronger because its cammed to do so, torque off the line, drop a gear and the 390 should easily walk away from a smogger 454.

My 390 in my 71 4x4 SB used to significantly outrun a buddies late 70's 4x4 SB Chevy with a transplanted and "slightly" more than stock 454 when empty (headers and an RV cam in the 454, mine has quite a bit more goodies). However, with our boats tied to the back, he'd pull a hill in 4th where I'd have to drop a gear on top, mostly due to cubic inches and cam design

[kaptnkaos]

Hey RobRoy...

Yer really comparing apples and oranges...
A 454 is in totally different league than a 390...
If you want to compare like that, try comparing a Chevy 350 with a Ford 360/390
or a Ford 428/429 to that 454... stock either will blow away the Chevy.

KaptnKA S

[fomocoguy]

There is some good information on the hp figures above, but as is usually the case with online sources there are some horsepower figures for the 390 that have been left out. In 1961 and 62 there were 300 hp and 375 hp 4 barrel versions, and a three 2 barrel 401 hp version of the 390. The listed figures look to be of base 2 barrel model 390's.

The 390 in the Thunderbird was rated at 300hp from 61-65, with a 340hp three 2 barrel option in 62 and 63. They were 315 hp from 66-68.

There was also a 320 hp 390 available in the 66-67 Fairlane and Mustang GT. It was raised to 335 hp for 68, then back down to 320 in 69, presumably becasue it was making the same hp as the 428. Only one 390 was available in 1970; only in full size Fords and making 265 hp.

These are all car engine stats, taken from "Ford Chronicle", a pictorial history from 1983, by James M. Flamming.

[LANCE65]

in STOCK form, the Chevy will overtake the FORD all day long. Now if you want to talk 428/429 of yesteryear,lest not forget the famed LS6/LS7 454. Like stated about this is an apples to oranges comparo. Now if you want to talk STRENGTH, the FE has ANY Chevy beat hands down.
-Lance

[My427stang]

Let us not forget, we are talking HIS 430 hp FE versus HIS 250 horse 454.

To get 430 hp you lose some low end, so you are a downshift away from embarassing your work truck, but idling around with a coffee in your hand, the 454 will feel just as strong if not stronger

[robroy]

Thanks for all the interesting replies!

I'll have to post to this thread again in a few months when I can actually compare the two setups (when my Ford is ready for action)!

-Robroy

[Dragon]

Hi!

My work/utility truck is a 1986 Chevy C20 454, and while driving it today I got to wondering how the FE 390 compares to it.

How would somebody experienced with both engines compare their characteristics? I know this is an open ended question, but do any valid generalizations come to mind?

Thanks!
-Robroy

I drove both 390 gas mileage was much better.
454 more torque
390 points and oil changes for 90,000 miles.
454 TBI Fuel injectors at 52000 same number of oil changes and one bottom end rebuild from pulling 5000 in 3rd up the same mountain dirt pass that the 390 did for 90,000 miles. PS. Both trucks ran for 3 years and clocked 90,000 each.
Hauling hay over the same pass.

Different gearing in both trucks the 454 in 3rd was at 65 and the 390 at 65 was in fourth with the same load.

454 torque band is narrow due to small port heads causing restriction. Remember the Chevy heads were designed for 396s Only hipo 454s got Lseries heads.

[willowbilly3]

I have one of each, not too proud of either one right now but no 454 would run 35,000 miles with no oil pressure like the 390 did/still does.

[rubiranch]

If you painted them the same color then they would be the same color.

[rubiranch]

"Chevrolet 454 SS vs. Ford Lightning", Motor Trend, June 1993

Lightning
0-60 – 7.2 sec
¼ mile – 15.6/87.4
HP - 240@4200rpm
TQ - 340@3200rpm


SS 454
0-60 – 7.2 sec
¼ mile – 15.8/84.7
HP - 255@4000rpm
TQ - 405@2400rpm

Even with a 100+ more cubes, more HP and more TQ the SS 454 was slower.


http://www.stangbangers.com/93_Lightnin ... rticle.htm