HorsePower

According the the Press Release article the 428CJ was rated at 335 Hp at 5400rpm and 440ft-lb torque at 3400rpm.

I was told that this is actually an underating for insurance purposes. Does anyone know what these babies actually put out at the Flywheel? at the wheels?

I also want to know what the Boss 302's ACTUALLY put out at the engine/wheels?

Also, how about the Boss 429's?

Thanks
David

David, I cant give you the exact off the showroom numbers, but I built a 428cj for my AC Cobra. The bottom end is standard parts, dished pistons (about 9-1 compression), though 30 over. On the top end, we put Edlebrock RPM Performer alm heads out of the box, regular hydralic lifters, stock rockers. We used the Edlebrock Rpm Performer cam which is more than stock, but not radical. Also Edlebrock alum intake, port matched. Used the same single Holley 750 double pumper 60s era carb. Have electronic ignition from MSD and had the Dist properly curved (important). Chipped at 6,000 rpm.

On the stand, at the flywheel, 462 hp, 524 ft lbs of torque. Pump gas, drive it anywhere we want to go.

On the 428, its more the torque that the engine makes rather than the hp. These old FEs have grunt.

Rule of thumb from the engine tuner, One hp per Cubic Inch with nothing radical on the FE. They probably did not have that off the show room for the most part, but pretty close. Best guess?? one 4 v, 400ish, two 4v (67 gt500) at 425 ish. Take the original engines, curve the dist, jet the carb correctly, gets over 1 for 1.

That from a rather novice, the real FE guys can make their opinions as well.

Brian

David, if you are really interested in the FE series (352, 390, 427 and 428 engines) you can go to Club Cobra web site. Those guys are real FE gear heads.

The only real outlier in the FE class of engines is the 427. It has cross bolt mains (only one in class). It was built primarily for racing and high RPM uses. Some have a larger oiling capacity (side oilers). The applications were in race use, boats and not much else. Usually Ford sold out of the 427 during the model year. In 65, they put 427s in the race cobras but used the 428 for most street versions. The Gt40 got the 427 in it for 1-2 years b4 it was outlawed by the racing commissions.

These 427s were favorites for Drag racers as they kept the RPMs high the entire run. I watched a show about the 427 gt40s at Le Mans. They told, though cant remember how many, fewer shifts they could make on the circuit (vs high reving, smaller displacement cars) because of the torque of the engine. That was what Ford hung their hats on for that race. Fewer drive train problems.

Do not know about the 429 or the small blocks. Though when we built the small block for our GT/CS, we had a tough time getting to the 1 for 1 on HP. So, I wonder if the 302 Boss was actually a 400 hp engine. I d need to see a dyno sheet to believe that. 300 maybe, 400, well it makes for an interesting discussion.

Can tell you this, the 428cj in the 2300 lb AC makes for a real exciting ride.

Brian

Wow those big block fords sound amazing. I would love to feel their pull, especially in a little Cobra haha.

Can you get to the spark plugs in a mustang engine compartment with the 428 in there? It is hard, in my opinion, to get to them with the small block in there.

Ya i dont believe the boss 302 made 400 horsepower stock either.

My blueprinted 347 with aluminum heads and good cam with msd and headers 700cfm holley, aluminum rpm performer intake is probably just under 400 horsepower.

Did you ever race the 428 in a mustang in the q/m? if so what was your e.t? speed?

how about the 428 in the little cobra? q/m e.t and speed?

Interesting tidbit - I visited a specialty engine shop in Wisconsin (Westech) and saw an AC Cobra that they had put a v12 Viper engine in - unbelievable power - and unbelievable miracle of shoe horning that engine in the small space. Casey

David, I have never driven a 428 Mustang, but as I remember, it takes a special set of heads to fit a FE in a mustang bay. Those heads are pretty restrictive. You know what that means. The q/m times I saw on the 390 stangs were not that much better than the 289 hipo cars. That was the reason not many FEs found their way into the stangs.

I have not timed my Cobra, but a buddy of mine built one same time, same basic engine, same car. He was well into the 11s with his car. He used a Victor Jr intake, but not much else diff. My guess is my car is about 12.0 or so.

So far as the spark plugs, the Stang 390s, as I remember, asked the owners to release one motor mount and tilt the engine slightly to get the plugs out. Frankly, unless you want a pure racing application, the small blocks are so sweet in the stang, just hard to imagine having a heavy big block up front. As well, keep in mind the extra weight of the big block on the front end, gave these cars a pretty nose heavy feel.

On the matter of the crazy folks, there is a guy in Mid ohio that puts the Dodge V10 in Cobras. Calls them Double Venom. A real hoss, but then again one needs to make decisions on drivability vs down the strip.

There is also a company that makes a supercharger for the FE engines. Not that hard to get 700 hp out of them. A company uses that set up in the "Super Snake" GT500, Ellenor cars. A real screemer ;D.

Like life, many decisions are a trade offs. My AC is very streetable, will hold the Home coming queen in the parade and does well in the car shows. At small road course tracks, the stroked small blocks do very well. I love the sound of the big block cars and the way they pull in the lower RPMs. Makes for a very drivable car that I can scare most folks in the riders seat.

In conclusion, I would not put a big block in a Stang that I expected to be a driver. I love HP and Torque, but this car was built for and works so well with the small blocks, just hard to do differently.

My 2 cents worth.

B.

There are 3 books that make for interesting reading about engine combos offered in the Mustang as well as options that were offered.

1. Kings of the Street (American Muscle Cars), published by Publications International Ltd. Copyright 1995.

2. Mustang, Forty Years, published by Motorbooks International 2003, an imprint of MBI Publishing Company, Randy Leffingwell w/photography by David Newhardt.

3. Chronicle of the American Automobile, Over 100 Years of Auto History, Publications International Ltd, Copyright 1991, By James M. Flammang and The Auto Editors of Consumer Guide.

As has been mentioned getting to the plugs on both the 428CJ and the 390GT is hard but not impossible. Having owned both a 70 Mach I 428CJ and currently owning a 68GT 390 Coupe and a 68 GT/CS 390 I have found the easiest way without undoing the engine mounts is to remove the Export Brace along with the Air Cleaner. Once those items are removed I simply use a 3/8 ratchet with extension and swivel. I have also obtained a spark plug wire tool from Advanced Auto which is angeled and allows me to get to the plug wires without too much trouble. The hardest part is the drivers side because of the power brake booster and master cylinder.

As Brian mentioned these cars were nose heavy with the big block. One way to offset that is change to even heavier springs and a bigger sway bar than the car originally came with. One has to keep in mind, when these cars were produced they weren't built to go around corners like many of the current Fox body cars or the Cobra bodies for that fact. The main thing most folks were worried about was torque and going in a straight line. Even with the modifications I've done to both my cars, the biggest problem I have currently is keeping the rear hooked to the ground.

I hope to have both cars on the dyno this summer and hopefully be able to get them to the track to see what kind of ET's I can get from both since one is an auto and the other a 4 speed.

Also, one of the first things I did to both cars upon rebuilding the engines was to have the stock heads ported and polished and matched to the intakes I put on both cars. I myself don't care much for aluminum heads (have had numerous problems in the past). I have also thought of putting a supercharger on the CS but, an not sure if I really need that kinda HP on the street. As they sit now they've got plenty enough to scare most folks with the mods I've already done. Besides, they draw enough attention at show's as it is.
If nothing else, one thing I've learned over the years of redoing several stangs is - "THERE IS ALWASY SOMEONE OUT THERE FASTER THAN YOU".

As far as folks not wanting the FE motors due to ET's I don't know about that. My 68 GT 390 Coupe w/C6 shows there were 1,343 produced with that engine and transmission and my 68 GT/CS 390 w/4 speed shows 1,194 with that engine and transmission. Several books I've read and conversations with other Ford folks have mentioned most people didn't order the FE's due to extra cost back in the 60's. That was also the reason you will find a lot of the big block cars didn't get ordered with Traction Loc rearends.

Don

This is one of the most impressive discussions here on these boards. Thanks, guys for the great info for us FE guys!

For my 390 rebuild, I've collected just about every article written on it, including the series that Street Rodder did a couple of years ago.

I don't need exotic, but plan on using the Shelby sidewinder intake and the Edelbrock heads. I'd like to use the (same) FE Police Interceptor cam (GT-390), but with today's gas, etc., would like to know what else would work as well or better. I plan on doing a vintage Shelby upgrade (as if it was late '68).

What are the downsides to Alum heads? Do they warp when they get hot?

I also noticed that JBA makes FE headers for the Mustang, because of the GT-500-E cars. A tri-y design.

Paul N.

Aluminum heads are great. Mine are AFR 185 (Air Flow Research) I heard they are the best and they certainly are great heads.

Would they warp is they got hot? If you overheat the engine to 250 degrees, a lot of bad stuff can happen. If you dont overheat your engine, then you wont have to worry about your aluminum heads. If your going to spend the money to get good heads, at the same time just make sure your engine will run cool. A tip from the racing guys who built my engine is that they didnt use a thermostat for my car. They use a restrictor which is just constantly open, that way there is no change for a 5 dollar part to fail and ruin your engine.

Thanks for the info, David!

I'm looking at Alum for the intake and heads for weight savings as much as new flow-power.

I guess I'd save something like 200 lbs? From a weight only standpoint--those cast iron FE heads make great boat anchors!

Maybe with the Alum--the FE would weigh the same as an all-iron 351C?

Paul N.

Paul,

When I built my 428, we used the total Edlebrock Performer RPM Kit. It came matched with cam, heads and intake. We did not get the carb as wanted a Holley for looks in the AC Cobra. The kit turned out to be a very nice package. Few of the cobra guys her in town went to that set up as well. Just put them in right out of the box with a little "kiss" on the intake runners to heads and little "kiss" on the outbound to headers.

From my research, the Alm heads will have more tolerance for mistakes. I gave David some of my experiences regarding "Dyno tuning" the engine and what worked for my engine. I forget what string it is on, but look at David s recent strings.

The engine builder and tuner I used for the 428 were big into matching the package. Their position is that too many folks buy really hot heads or really hot cam, or really big carb, but when put together, they dont perform well. Thus, the package. It worked better than we ever expected and the package was cheaper than buying different pieces.

Some of the cobra guys here buy the Edlebrock Perfomer RPM intakes and grind off the name and polish it out. They look very similar to the Ford PI of days of old. With the Heads, cam and intake set up, Edlebrock should be able to give you very good ideas on Dist/timing set ups.

As a side note, we Power coated our intake with clear. It really is a neat deal when you are dealing with the prospect of leaky fuel lines and perhaps a leaky Valve cover gasket. No nasty stains on the warm Alm intakes. Wipes right off

Now the caution, make certain the heads will allow your headers or manifolds to work. As I remember, the big block Mustangs required special GT heads that shot the exhaust down rather than out in order to get the exhaust manifolds between the towers. So, check that.

I personally love the smell of 91 or 92 octane off the Alm heads. Not an Edlebrock salesman, but these guys got a lot of HP/TQ out of an engine that spent many years on an irrigation pump in western KS. Dished Pistons and all. Very reliable engine as well. No heating problems.

You are correct the weight is much less. Dont know if its 200 lbs or not, but much less. You might consider buying a high volume alm waterpump as well. Helps keep the engine cool and saves several pounds.

I personally have never had a therm stick. My engine produces the most HP/TQ at between 155 and 165 degrees. Some like more heat, some less. That is why many drag guys get their car up to temp, shut them down and not start them again until they get near the line. The real high HP engines typically make more hp at cooler temps. I run a 180 therm in my FE.

Brian

Sorry, Meant Powder Coated instead of Power coated.

Brian

Final note on FE stuff, The Club Cobra site has a FE forum if you are interested. As I said, some of those guys are real FE nuts. They have about tried it all, some successfully and some not so successfully. You might visit that site if you have some real deep FE questions.

Brian

I found on my 91 LX 5.0 I had, when I rebuilt a 93 cobra block with a 347 stroker and aluminum edlebrock heads the biggest problem I had was constantly loosing my header bolts. I finally discovered that Stage 8 makes a locking bolt kit you can get for the headers that works very well. I also had the same problem with my 390 heads right after we installed the headers. Wound up putting Stage 8 locking bolts on those as well.

Be careful buying headers depending on the manufacturer. I put Hooker Ceramic Coated headers on both the GT and the CS but, the kind folks at Jegs didn't tell me Hooker only makes a header for standard 390 heads not the GT head. We found out after I got them to the engine shop. Bolt pattern is totally different. Pulled the headers and pre-drilled required holes to fit the GT head.

As for running no thermostat wouldn't recommend it on a FE motor. When I purchased my CS that's what was in it (no thermostat) and it constantly overheated. Water/Antifreeze in radiator didn't have time to cool down. If your using it just for a drag car not a problem but, if it's a street car you don't want to be in traffic. Like Brian, I'm currently running a 180 degree thermostat with no problem and an aluminum water pump. Ford recommends a higher thermostat for the 390 but, the 180 works fine. As for thermostat, Mr. Gasket makes what they call a balanced thermostat that is different when compared to a regular one. It has a small canister section on it and they are gauranteed not to stick. That's what I'm running in both my cars and have had no problems.

As Brian also mentioned, complete packages are the best way to go. Most folks will have their stock heads ported and polished and just throw a gasket kit on them and not check how they match up with the intake and headers. You wind up with extra gasket material blocking the air flow (can really effect everything). When we sent my heads out to be worked I also sent the headers, and aluminum intake along with the gaskets and had everything matched.

Hey Brian; What's a good fix for keeping valve cover gaskets intact? :'( I've already gone through several sets. I've tried both rubber and cork. Most folks tell you to just keep tightening the bolts but, with chrome covers you wind up bending them or warping the darn things. My next shot may be just using gasket sealer and see what happens. Don't know if it would benefit to maybe drill extra holes in the covers and head area. Ford should have put more bolts in that area. Problem usually shows up either in the front or back of valve cover.

Don

Don, my rather limited experience with valve covers and the gaskets is that most people tend to over torque. If one over torques them they warp the valve covers and lead to a leak. I do not know the correct torque in lbs, but the folks who taught me said to use a 3/8 inch socket, ratchet set up. Hold the ratchet right near the center section. Use one hand, titen without torquing the body. Tested, I think it is around 30 lbs plus/minus.

On both the big block 428 (it has Cobra Alum valve covers) and the small block for the CS (it has alm "Powered by Ford" covers) we worked in that way.

When I built the Cobra, we looked at the Chrome valve covers. Many original Cobras got chrome valve covers for street use. The caution was given to me to buy expensive chrome covers. Reason, the cheap ones (thin ones) warped. :-\

Soo, you will have to measure your valve covers. Three possibilities, 1. they have never met a gasket they like (unlikely). 2. they were good chrome Valve covers, but were torqued too much and thus warped, or 3. They came warped and you just got Scr@#$. At any rate, we decided to buy alum as they were stronger and allowed for more error when torquing. In short, if you can not get them to seal, it is probably because they are warped for whatever reason. You will have to be the judge of that.

As a side note, we Powder Coated Clear our Alum valve covers as well as our intakes. In my Cobra, the valve covers lost torque. They leaked, we were thankful they were powder coated, they cleaned right up. Did the same on the CS covers as well. Highly recommend that trick.

I have not lost any torque on my header bolts on the big block. Nearly 7,000 miles. Some high rev as well. Used regular header bolts.

I absolutely agree to send your heads, headers, intake and gaskets together. I made that mistake by not "Port Matching" the gaskets on the intake side. See other string started by David. It nearly cost me the heads. Ran the back cylinder way to lean. Nearly took that temp off the chart. Thank God the engine tuner caught it and we corrected it nearly immediately on the Dyno stand.

Brian

Hello, don't forget the 429-460's I have a 460 stroker and poked to a 557 and it is making around 900 naturally aspirated. I just put the engine combination together and my car weighs 3100 and without tuning I ran a 9.26 at 149 mph. I wanted to reset the timing to 34 and adjust the jets but I ran out of time.I do drive the car on the street but it will smoke the tires when you are driving about 60 mph. It is a real thrill. I work on a cobra that has a 427 in it, it has lots of torque. If you guys want to go for a thrill ride come to Gettysburg.