Underrated muscle

[Stoner133]

Underrated Muscle would be the 1969 Hemi Road Runner. We all know the Hemi was well underrated at 426HP to keep the insurance companys happy. I would have said the 89 Hemi Dart but it was more of a factory race car while the Road Runner was a fun car for the masses.

[[XC] Lead Head]

The 426HEMI was overrated with stock factory tuning Just look at the old magazine reviews of those cars. They ran much slower times in the quarter-mile then they should have with how much they weighed and how much power they were rated for.

Almost every big engine (actually almost any engine period) back then was overrated. It has to do with SAE Gross measurement vs. the more modern SAE Net measurement.

[Sn0wm@n]

you know this has brought me thought now superchargers or turbo/'s ?

what do you think is better ?

turbocharger of course .... supercharger need energy to create energy ... and turbo uses waste energy to create more energy ....

The answer is both.

It depends on what you want. If you want instant boost at the expense of a loss in efficiency then a supercharger is what you want.

If you want a more efficient setup but don't care about turbo-lag, then a turbo setup is what you want.

with today's modern turbo setup the word lag doesnt exist anymore .....

[demonkevy666]

What's the max PSI of a Turbo charger ?
I've found the max of a supercharger already but no turbo's specs :/

[dengyong]

What's the max PSI of a Turbo charger ?
I've found the max of a supercharger already but no turbo's specs :/

There is no real limit... fuel, engine components and tune are the limiting factors. As air is compressed it's also heated... low pressure/high volume is what you want.

Some race diesels (tractors) use four turbos to produce 100psi.

In a gasoline street engine, most don't use more than one bar (14.7psi at sea level), with 5 to 10psi being the norm.

I'd also like to note that "manifold pressure" is mainly a function of intake restriction... meaning, if you take a forced induction engine that makes 10psi and reduce the intake restriction through the use of porting, larger valves and more efficient intake, all else being equal, the manifold pressure will go down but the power output will go up.

[[XC] Lead Head]

with today's modern turbo setup the word lag doesnt exist anymore .....

For lower HP applications yes. But from what i've seen if you want big power, there will be significant lag still.

[zanzabar]

For lower HP applications yes. But from what i've seen if you want big power, there will be significant lag still.

they fixed that with variable geometry for the larger turbos, if u dont get lag from a single giant turbo on the caterpillar engines then i dont think cars would have to worry. there may still be lag from idle though, but thats generaly good so u dont break traction for a split second if its even there.

[hutkikz]

The 426HEMI was overrated with stock factory tuning Just look at the old magazine reviews of those cars. They ran much slower times in the quarter-mile then they should have with how much they weighed and how much power they were rated for.

Almost every big engine (actually almost any engine period) back then was overrated. It has to do with SAE Gross measurement vs. the more modern SAE Net measurement.

most performance engines in the 60's were underrated to get a better weight/power rating on the drag strip.(looks at 2 bookcases of pre 70's old car mags)
stock classes were determined by weight/factory rated HP
just gotta love the "race on sunday,sell on monday " attitude back then

also have to agree with Stoner about the 69 roadrunner although I admit a bias since we have one in our shop right now for a new suspension and I got to break it in last weekend

[PaganII]

Early 70's Ranchero with 429ci, El Camino with 396/427. Sunbeam Tiger w/289ci Ford was used in the ancient Get Smart TV series. https://secure.wikimedia.org/wikiped.../Sunbeam_Tiger wow, I really thought they made more of these.
My dad rented a Hertz GT 350 Mustang for my sister's wedding to use as the "get away car".
I remember a mid engine 426 hemi Barracuda at the dragstrip.
http://www.musclecarcalendar.com/las_vegas_15.htm
I was lucky enough to watch a wheelie contest/race between the Little Red Wagon and the Hemi under glass. They crossed the lights at the 1/4 mile mark and kept going to see who would back down first!
http://www.google.com/images?q=Hemi+...OsL58AbvwriACQ
Little Red Wagon http://www.allpar.com/model/littleredwagon.html
Mid 60's Ford, Dodge & Chevy made these 90" wheelbase trucks like a van with a pickup bed. Small V8's drop right in. I think the ford had a V8 option.

[demonkevy666]

I just don't believe that 20% from engine to power a superchargers.
turbo's are not free horse power either.

[silverphoenix]

I just don't believe that 20% from engine to power a superchargers.
turbo's are not free horse power either.

I have the list somewhere about top fuelers, they require the same power of a Hemi to just turn their damn Superchargers.

[[XC] Lead Head]

I just don't believe that 20% from engine to power a superchargers.
turbo's are not free horse power either.

I have the list somewhere about top fuelers, they require the same power of a Hemi to just turn their damn Superchargers.

8,000-10,000HP top fuel dragsters require 900HP to turn the blower.

[[XC] leviathan18]

There is no real limit... fuel, engine components and tune are the limiting factors. As air is compressed it's also heated... low pressure/high volume is what you want.

Some race diesels (tractors) use four turbos to produce 100psi.

In a gasoline street engine, most don't use more than one bar (14.7psi at sea level), with 5 to 10psi being the norm.

I'd also like to note that "manifold pressure" is mainly a function of intake restriction... meaning, if you take a forced induction engine that makes 10psi and reduce the intake restriction through the use of porting, larger valves and more efficient intake, all else being equal, the manifold pressure will go down but the power output will go up.

I run 21psi peak with 17 sustained

[Stoner133]

The 426HEMI was overrated with stock factory tuning Just look at the old magazine reviews of those cars. They ran much slower times in the quarter-mile then they should have with how much they weighed and how much power they were rated for.

Almost every big engine (actually almost any engine period) back then was overrated. It has to do with SAE Gross measurement vs. the more modern SAE Net measurement.

Of course they ran slower then they should have. What would you expect to happen when your dumping all that horsepower and torque though a set of stock F-70 Redlines. All moters from all manufactures were underrated back in the 60's till 72 not overrated. OEM street tires back then left much for improvment. HEMI Roadrunners would spin L-60's easy, the stock F-70's just boiled away. 427 Fords, 427 Chevys, W-30 Olds all underated from the factory.

[Stoner133]

most performance engines in the 60's were underrated to get a better weight/power rating on the drag strip.(looks at 2 bookcases of pre 70's old car mags)
stock classes were determined by weight/factory rated HP
just gotta love the "race on sunday,sell on monday " attitude back then

also have to agree with Stoner about the 69 roadrunner although I admit a bias since we have one in our shop right now for a new suspension and I got to break it in last weekend

Actually I should have added the 68 HEMI Roadrunner, it's my favorite of the two. I liked the air inlets in the hood better on the 68. 70 model wasn't bad but didn't really care for the new grill and tailights, while the air grabber for 70 was cool.

[dengyong]

I run 21psi peak with 17 sustained

That's why I highlighted the word "most".

Now it's time to look for ways to increase volume and reduce pressure.

[[XC] Lead Head]

Of course they ran slower then they should have. What would you expect to happen when your dumping all that horsepower and torque though a set of stock F-70 Redlines. All moters from all manufactures were underrated back in the 60's till 72 not overrated. OEM street tires back then left much for improvment. HEMI Roadrunners would spin L-60's easy, the stock F-70's just boiled away. 427 Fords, 427 Chevys, W-30 Olds all underated from the factory.

People have dyno'd these vehicles with their stock factory tuning. Many of them would have been lucky to break 350HP at the crank, let alone their quoted 400-440HP.

Throw big set of carbs on them, crank the ignition timing and uncork the exhaust and you'll open those engines right up.

[Stoner133]

People have dyno'd these vehicles with their stock factory tuning. Many of them would have been lucky to break 350HP at the crank, let alone their quoted 400-440HP.

Throw big set of carbs on them, crank the ignition timing and uncork the exhaust and you'll open those engines right up.

Just as I have seen the HEMI dyno'd at 475HP as well is stock form. It has to do with who is running the dyno. They can be manipulated to give false results.

Yes, I agree you can throw bigger carbs, and tune the ignition timing and uncork the exhaust and put better tires on them to get much more power and traction out of them. But then they wouldn't be stock anymore either.

[RAW-Raptor22]

The 1989 Ford Thunderbird Super Coupe, while it was the 1989 MT Car of the Year, the SC wasnt as successful as it should have been.

It had a Supercharged 3.8L V6 with a 5speed manual transmission. It came factory out of the box with four wheel independent SLA suspension, speed sensitive steering, four wheel disc brakes with ABS, and even automatically adjusting shocks from Tokico in Japan. The SC featured space age technology in a car that was pretty much a sleeper.

Ford set out to beat BMW and they did:

[demonkevy666]

8,000-10,000HP top fuel dragsters require 900HP to turn the blower.

Wikipedia

I love that sleeper Thunderbird (4.6L though)

[PaganII]

4.6L was a great motor, smooth like electric but the early auto transmission they mated with were junk. The manual lever position switch (MLPS http://www.gottransmissions.com/blog...osition-sensor ) would get wet and then the clutch plates would burn up. Rebuild required replacing planetary gears and other stuff with updated 1996 1/2 and up parts.
Then Ford decided to switch from aluminum to composite intake manifold that cracked.
I'm looking for a 93 Tbird with a 5.0L. 93 did not have the god awful computer controlled tranny nor air bags. Already have a built engine that's why.

[RAW-Raptor22]

Wikipedia

I love that sleeper Thunderbird (4.6L though)

4.6Ls are nice too but the suspensions were too soft from the factory, however a change in springs and the car is a whole new animal.

4.6L was a great motor, smooth like electric but the early auto transmission they mated with were junk. The manual lever position switch (MLPS http://www.gottransmissions.com/blog...osition-sensor ) would get wet and then the clutch plates would burn up. Rebuild required replacing planetary gears and other stuff with updated 1996 1/2 and up parts.
Then Ford decided to switch from aluminum to composite intake manifold that cracked.
I'm looking for a 93 Tbird with a 5.0L. 93 did not have the god awful computer controlled tranny nor air bags. Already have a built engine that's why.

Agreed, I am a member of the TCCoA (Thunderbird/Cougar Club of America) and we hear about that stuff all the time. The MLPS and Intake manifold issues are generally the 94-95 cars, the problems were worked out for the 96-97s.

TCCoA

Im looking for a 5.0L to swap into my 1989 Thunderbird (3.8L NA) with an SC suspension swap (bigger roll bars, Tokico shocks, speed sensitive steering rack, Eibach springs...). I basically eventually want a 5.0L with a 6speed standard transmission.

My car:

[Kai Robinson]

I do like the old Plymouth Roadrunner....but i still maintain that these things not only look cool and different, but are sorely underrated and forgotten;



Yep. Still the AMC AMX. I want a 390. Interesting to note that the AMC V8 still has lots of NEW performance parts made for it in the aftermarket...

[[XC] Lead Head]

You'd be surprised at just what you can get for engines that haven't been made in decade. Not 100% positive, but I believe somebody even restarted the production of the Ardun hemi-head conversion kit for old Ford flathead V8s.

[zanzabar]

I do like the old Plymouth Roadrunner....but i still maintain that these things not only look cool and different, but are sorely underrated and forgotten;

http://media.motortopia.com/files/54...b/DSCF0208.jpg
Yep. Still the AMC AMX. I want a 390. Interesting to note that the AMC V8 still has lots of NEW performance parts made for it in the aftermarket...

it really is to bad that dodge picked up amc and jeep and all but killed their legacies, but then they are also supported mopar part makers and they will never stop making parts for less popular random engines