440 Performance numbers

[jabo]

Hello!

I am from germany and my english isn't very well but I hope you understand me. I bought a 70 charger (with an engine swap) from an other geman guy and he can't say some performance numbers. But he gave me an email from the owner out of the USA with some data. My questions are --> What performance numbers will it make??? Does someone now what means that EHP? And is that engine good for some more performance?

6T 440 EHP
Block from end of 1975 (?76?) .030 over
6T=1976er truck motor?
EHP: E=Cast crank, H=Standard 4bbl V8, P=Premium fuel !OR! HP=High performance
Under this 1 19=19. January
Replacement flattop pistons
Stock crankshaft and rods
Comp cams with
292 duration and .501er lift
Head castings end with 516 (73,3cc) closed chamber from 64-67 361/383.
Intake valves 2.14er (2.08 original)
Exhaust valves 1.88er (1.60 original)
Ported and polished
Intake is a holly street dominator
Carb holly 750 double pumper
Stock ignition with hight performance orange box from mopar,
Damper #3577785 (cast crank Bj. 73-75)
Block: #4006630-440-9
Block date: 11.5.75

[jabo]

I am into the correct corner? Or did I forget somesing? Or is my english too bad? 

[cdr]

someone will respond,, your English is good!!!
I would say,depending on actual compression it is probably 320 to 360   hp

[firefighter3931]

Welcome aboard Jabo 

These are some unknowns that make predicting the horsepower numbers a best guess at best ? 

The intangiables are the cylinder head flow numbers and "actual" static compression. 

If the heads flow descent and the compression is in the 9.5-10 range it should make descent power in the 425hp range and close to 500 ftlbs of torque with that cam and good flowing exhaust with headers....


Ron

[John_Kunkel]

6T 440 EHP

6= 1976
T= Built at the Trenton engine plant
E= Cast crank
HP= High Performance

The 516 heads, although advertised as 73.5 CC's, are in reality around 78 CC's so your "Replacement flattop pistons", if identical to the originals (1.926" CH), means you have a compression ratio of around 8.50-1. Doesn't really compliment the other mods.

[jabo]

Oh, some answers  

Thank you for your help! (1)Does someone now my compression or must i measure the distance from piston to deck at TDC? (2)And than measure the combustion camber with water and a ?glas/window?
It has no stock headers and a 3" exhaust from flowmaster. And I now that the owner run 12.8 times on 1/4 mile in norwalk with 15" rims and 275 mickey thompson tyres. (That numbers are on a picture from the windsheld of the car). (3)Will be the cast crank ok for some more HP? (4)What heads do you recomend for a nice combo? (5)The great distance from 320HP to 425HP is only caused by the compression??? The old owner told me that i only buy premium fuel (92). I hope it help.

very nice to have some experts!    In germany no one now something about this nice cars  

[cdr]

by knowing the weight of the car & the MPH it runs at the track, HP can be calculated. the ET can also be used but MPH is more accurate. so lets say your car scales at 3900 lbs & ran 12.80 the math says

Your HP is 367.56 computed from your vehicle weight of 3900 pounds and ET of 12.8 seconds.

thanks Wallace calculators    http://www.wallaceracing.com/et-hp-mph.php

[Challenger340]

Not very much power.
Unknown Piston being my biggest concern, other than "replacement Piston".... which usually means the notoriously low-pop cast piston offerings.
No matter the 2.14/1.81 Valves.... maybe 400-425 hp and very poor torque

[jabo]

Argh... the picture is too big/large. Than i explain the picture.
On the windscreen you can see:

SPT
4350
12.8

12.8s is the ET time?! And the other signs are the weight and race class?

[Ghoste]

That would be my guess.

[BSB67]

Don't feel bad.  I'm from the United States, and my English isn't very good either.

Sometimes people get confused in thinking that the power output is simply a compilation of the parts they have.  Certainly that is a significant component that will generally define an upper bound on the power potential, but it is the finer details of machining, parts compatibility, assy technique, and very importantly, tuning.  Two guys can start with the same box of parts, but one guy might make 100 more hp than the other guy.

Assuming that the motor has low compression, I would say that all of the responses that have a guess to the hp could be correct.  Depending on the details, It could be 300 hp, or possibly 425 hp.  350 to 375 is my guess for actual power.

Low compression (generally bad piston choice) is crippling when it comes to trying to significantly improving performance.  This is why Bob keeps harping on this.....piston choice.  You cannot fix it without a lot of pain and cost, and you really cannot work around it very well.  The reason is not the low compression ratio itself, it is the low cylinder pressure that usually comes with it.  Higher cylinder pressure = higher power through the entire rpm range.  Another key element of more power is more air/fuel into the motor.  Generally, once a motor is put together, your cam is the simplest way to effect intake charge.  So here comes the rub: When you already have low cylinder pressure, it gets even lower when you put a bigger cam in the motor, and from a power output stand point, you are going down a path of diminishing returns.  You can actually get to the point where a smaller cam will make the car faster.

So, IMO, the easiest way to put more power in that motor would be cam or cylinder head change, and both would be better.  For the cam, a fast rate solid flat tappet cam up to about 240° @ 0.050". on a 108° LSA, in at 104° would work.  This will probably not add much peak power, but will add noticeably to average hp, make the car faster, and sharpen up the lower rpm power.  For cylinder heads, ported aftermarket aluminum with small combustion chamber, and have them milled to the lowest practical volume (70 cc or less).


Finally, I tell street guys that I can add a proven/documented 20 to 30 hp to their cars for less than $100.  It is called track tuning.  Instead, they usually spend $500 to $1000 on parts and tell themselves that they have 20 or 30 more hp.

Now that I'm done babbling, you should probably do a cranking cylinder pressure test.

[John_Kunkel]

The ET tells me has better than the standard low compression pistons. The '68-'69 "stock replacement" pistons with the 516 heads would give closer to a 10.5-1 CR.

[BSB67]

The ET tells me has better than the standard low compression pistons. The '68-'69 "stock replacement" pistons with the 516 heads would give closer to a 10.5-1 CR.

You could be right.  I think it is still hard to tell w/o a mph, car weight and some atmospheric data.  12.8 could be 106 mph at 3900 lbs at a DA of 0 ft, or is could be 112 at 4100 lbs w/ a DA of 3000 ft.  That is about a 100 hp swing.

[jabo]

Ok. And the 10,5:1 CR will be ok for street strip application? I read heads like my flow 240cfm. Now some better HP ratings?  But i forgot to tell that the car has a 2000 stall converter 

I found two different ft for norwalk raceway. One say 876ft and the other 849ft.

Today i am searching and working at some 200KB pictures from my restauration (for your nice answers). I hope you will enjoy!

[BSB67]

1) Is your fuel octane rating 92 RON or 92 (R+M)/2.

2) Do you know which MT 275 tire (ET Street of Street Radial or something else)

3) Do you have the picture from the track?

4) What gear ratio is in the car when at the track

5) How long ago was it at Norfolk?

John is probably right that it is not an 8.5:1 motor.  I get 9.5 to 10.0 or so if the motor has the somewhat frequently used 1.99" CH piston with a 77 cc chamber, depending on the head gasket used. A lot of assumptions.  240 cfm is probably a reasonable head flow number.

[jabo]

QBSB67

1.) I mean (R+M)/2

2.) Oh, I don´t now. But I have some pictures

3.) Yes, I hope it is under 200KB

4.)I don´t now. But it´s a 8-3/4 with #2881489 number on it

5.) In 2006 (norWalk)

[jabo]

But now my resto pics!

Does somebody now the insects?
The brown coating is "Fertan" (a rust converter)

[jabo]

Now some metall work with tinning

[jabo]

Now some more tinning and very bad welding from the old owner

[jabo]

Little wheel well work for bigger rims/tyres

[jabo]

Some work into the rocker panel

[jabo]

Some more rocker panel work and some glas blasting worke. Very nice finish!!!

[jabo]

Now some quarter panel work with my own nice tools 

[jabo]

Some more space for the tyre

[jabo]

Welding