Is it worth modifing the guts if i keep a stock look

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I want to keep my 67 mustang looking original under the hood. So changing the carb or exhaust is out of the question. I wouldn't mind however a few more horses out of the engine. Would changing the cam or grinding the valves be worth the effort if i am stuck with the same carb and exhaust?
 
Yes.

The stock 200 gives you around 67 rear wheel hp, or about 90 hp net (as installed) from its 120 or so gross (stripped) hp .

There are some bigger 1-bbl carbs around. Some of the 1967 240/300 Ecconoline/F150 carbs are well over 200 cfm and depending on if it has the SCV ignition, you can use on of those.

There is possibly a better earlier exhast pipe (which on some Econolines, Broncos and Falcons) which can be used.

If the whole exhast system is big enough in diameter, has a great aftermarket muffler, and you have a 264 cam and a bigger intake and exhast valves, you may get a really big boost. If you run a wilder cam, you can optimise the igniton with much more advance without getting knock.

Use the Clifford port divider, and you can gain 8 hp or so.

Some desktop dyno tests run by Jack Collins (MustangSix), and some dyno work by 80Stang show about 114 to 117 hp net is possible. That's a gain of 27 hp, or 30% or so with no visual differences.

The true beauty of the engine is that even with a 1-bbl, the limit is not the carb, but the cam, head and then the exhast. Ford used the same 200 cube head, carb, cam and exhast on the bigger 250 in its first year, then spent the next 11 years fiddling with exhast headers, heads and cam profiles to keep it's performance up to scratch in the big old Granada.

You should do the same as Ford did. Carb, cam, head, and then work on the stock header like suggested in the Falcon Six Handbook.
 
Sparky,

There's a lot of very effective porting you can do in the stock head. Pocket porting, some reliefs to unshroud the valves, opening the exhaust ports, matching the and porting the exhaust manifold all will help.

Add a mild cam, a larger one bbl carb, and a Duraspark II under a small cap with a hidden GM or Mopar module and you end up with some very stealty improvements.

Over all, you could probably sneak in a 20-25% gain in power and keep the whole thing looking stock.
 
Howdy Steve:

Let me add another "Yes" to the above.

AKT '67 was the 1st year (48 state) of the non-scv, down sized Autolite 1100s. The '67 & '68 200s got a 150 cfm carb. Prior year 200s had a 185 cfm! The '67 & '68 carbs did not have a spark control valve (SCV) but had a ported vacuum source for the new distributor which has both centrifugal and vacuum advance. Ironically, FoMoCo advertized the same HP and Torq for both the '66 & '67 model years. I seriously doubt that the distributor upgrade could make up for the loss of cfm in the carbs

AKT ford advertized a 9.2:1 CR in 200s from '65 to '67. From '68 to '70 the CR was listed as 8.3:1, with no discernable differences in the head castings from '65 to early '69. So much for honesty in advertizing!!

Since you don't give your home info you should also know that Calif Emmissions equiped engines saw the carb and distributor changes beginning in '65.

The good news is that all Autolite 1100 one barrel carbs look identical externally. The engines with an auto trans do have a dash pot on the bowl, opposite the accelerater pump. And, better yet, the 1969 250 Mustangs used an Autolite 1101. It is also an 1100 look alike. It is rated at 215 cfm.

Now for the details-
Is this an Auto trans 200?
Where was it originally sold/manufactured?
What is the casting code on your head?

The answers to these questions will tell us what carb you have and if the head is one designed for the "Thermactor" air pump system emmissions system that was mandated in California in '65 & '66, and many other states from '67 to '70. These "Smog" heads will limit the performance potential of the head and the engine.

Know that you could upgrade to a '78 and later head with only the most discriminating knowing the difference by looking. These later heads look almost identical to your '67 head, but have; a larger carb hole, larger intake tract volume, larger intake valves, hardened valve seats. The only down side is that they have a larger chamber volume, but that can be dealt with easily.

So, YES! Internal mods are worth it while maintaining a stock appearance. It just take a bit more planning and coordination. I hope you go for it.

Adios, David
 
CZLN6":38h3ampe said:
Now for the details-
Is this an Auto trans 200?
Where was it originally sold/manufactured?
What is the casting code on your head?

Thanks guys, here is the data you asked. Yes i will be using the original C4 auto trans with the 200. My car was sold in NJ and manufactured in NJ. There were a few numbers on the intake which i think are what you want. C6DE-6090-B. I also have a head from a 66 engine which has a D7BE-60980-AB. The 66 engine i picked up from someone wanting to get rid of it so i don't have a whole lot of info on that other then the Block number was the same as mine. I also have another 200 6 cyl from i think a 68 becouse the block number is different then mine.

Keep in mined that this going to be primarily a show car so changing things like the exhaust is not an option. Using a different carb that looks and connects identically to the one i have is an option. I figure if i ever get knocked becouse of it i can always easily change the old one back in.

Now lets see if i can summarize all that information.
1.get and read falcon six handbook
2. find a Autolite 1101 from a 69 250. Will this do me any good if i dont upgrade the heads?
3. porting of the heads and exhaust manifold. (going to need more info here not to familiar with the porting process)
4. change cam maybe a 264. Which will do what move my peak HP to were about?
I am going to leave the ignition and exhaust suggestions out for now since they sound risky for some one who is trying to keep everything looking stock.

Thanks for the input so far keep your suggestions coming as i look into the other small items mentioned. :D
 
CZLN6":1ujj0rvu said:
Howdy Steve:

Let me add another "Yes" to the above.

AKT '67 was the 1st year (48 state) of the non-scv, down sized Autolite 1100s. The '67 & '68 200s got a 150 cfm carb. Prior year 200s had a 185 cfm! The '67 & '68 carbs did not have a spark control valve (SCV) but had a ported vacuum source for the new distributor which has both centrifugal and vacuum advance. Ironically, FoMoCo advertized the same HP and Torq for both the '66 & '67 model years. I seriously doubt that the distributor upgrade could make up for the loss of cfm in the carbs


Adios, David

One more thing while researching carbs i found this http://www.ponycarburetors.com/default.asp?page=faqdetail&id=20
which seems to indicate that the 68 was the only year with the smaller carb.
 
Howdy back Steve:

I stand corrected. I was confusing the '66 & '67 Calif/Emmission 200 with the changes to 49 state changes. Good job researching. The change to the Autolite 1100 was in '68 & '69. No SCV, a ported vacuum source and downsized venturi.

Thanks for sharing the Pony Carb source too.

Look the D5 - B head over carefully. Several I've seen have been Thermactor type heads. Does this engine have an extra pump driven off the front of the engine with pipes to a tap above each exhaust port? If so, I'd reccommend the D7 head for rebuilding.

On the head, get the valves redone. Be sure to specify a three angle valve job, back cut the intake valves, and mill the head to compensate for the thicker aftermarket head gasket. Any cleaning up of the ports, polishing the combustion chambers will also help.

Adios, David
 
CZLN6":1aflucyg said:
Look the D5 - B head over carefully. Several I've seen have been Thermactor type heads. Does this engine have an extra pump driven off the front of the engine with pipes to a tap above each exhaust port? If so, I'd reccommend the D7 head for rebuilding.

D5-B ? i dont think i have a d5-B head not that it matters neither seems to have holes in it.
 
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