200 heads...65 vs 71

6

62 Comet

Well-known member
Hey again guys, just a quick question about heads, I was just wondering if there are any pros or cons when it comes to comparing these years of heads

The 71 is currently in my dd and the 65 is from the motor I have pulled apart. Are they any differences?

Thanks guys

Lee
 
The 71 head is one of the best of the early small 1.65" intake valve log heads. It has an enlarged hole for the carb, with the larger log intake volume, and normally, the chamber sizes are normally approx 59 cc, not 52 cc, although there may be 52 cc versions of it. It may be found on a 170, 200 or 250, with a special cast in boss for the kickdown rod C4 below intake tract 5 and 6.

As to its advantages, the flow of the smaller 170 version with its smaller chamber is the reason for a huge increase in base flow from 105 to about 125 cfm at 25"H20, all stemming from its better quench and more favourable unshrouding when fitted with bigger valves. According to this article


http://www.invectivus.com/hrm_mustang3/ ... 20copy.jpg


which Invectus reheated for us, when kitted out with later big valves from the 1976 to 1983 and relieved to suit, it flows considerably more cfm than the best 1976 to 1983 heads.

The whole links are

Based on Ak Millers /Jay Storer HRM's mustang magazine number 3
http://www.invectivus.com/hrm_mustang3/Cover.jpg
http://www.invectivus.com/hrm_mustang3/ ... 20copy.jpg
http://www.invectivus.com/hrm_mustang3/ ... 20copy.jpg
http://www.invectivus.com/hrm_mustang3/ ... 20copy.jpg
http://www.invectivus.com/hrm_mustang3/ ... 20copy.jpg
http://www.invectivus.com/hrm_mustang3/ ... 20copy.jpg


 
Howdy Lee:

I'd suggest that you do some measuring and eyeballing both heads more carefully. For example was the '65 head from a 170 engine or a 200? Both will have a 1.5" carb hole, but only the 170 engines got the smaller "Kidney bean" chambers. The casting most generally seen on the small chamber heads is C4DE-D. 170 heads with a C5DE-A & B Castings have the larger chambers. The small chamber "D" castings have an intake tract volume of 890 CCs, while the large chamber volume heads have an intake tract of 1100 ccs.

1971 was in the transition years for head casting changes. The only thing that can be said with some certainty is that this head will have 62 cc chambers and 1240 cc volume chambers. Valve sizes will be the same in both castings, but the '71 head will likely have induction hardened exhaust valve seats.

Depending on your intended use either can be modified to accommodate. What are your goals and intended uses?

Adios, David
 
The 170 Head with the small chambers , and big carb throat is what I have on my 255 inch Motor , I patterned my entire build after that early 70's article , the later head is designed with EGR in mind , using it without the proper timing curve is ping city, so sadly it flows better , but is NOT always better , depends on the goals / combo
 
Really appreciate all the info guys..

As for what im doing, I currently have the 264/264 112 LC cam ffrom CI. Nothing too special just a totally freshened up DD engine. I am leaning towards a 2 bbl Weber 32/36 conversion, if you guys have any suggestions I would love to hear them.

The 71 on my dd has an egr so I think you wouldn't be able to take it off and bolt on the carb right to the head. And just by looking it appears the 71 has a "larger" intake log than the 65, does that make it any better? Both heads are from 200's.

Lee
 
is your car a automatic or stick ? , that cam in a 200 with an automatic will be disappointing everywhere but in park , sorry but a 200 is a small engine , I still see the V-8 mindset applied to cam choice and IT IS WRONG if you want a cam change in a automatic equipped 200 and want everything else to be stock , I would choose the smallest cam available over stock , with a stick 2 steps , NOW if you raise the compression to the limit ( say 9-5,10-1 ) that would be then be OK in a stick ( your original cam choice ) but you would still need an aftermarket converter with a 2800 min flash stall ( based on a 200 inch engine ) Also having your Dist recurved is a must , if its a loadamatic , replaced ( sorry they are a poor design )
 
I agree with the too big of a cam and the v8 mindset with the small 6s. Most of what I see after market is just way too big for a streetable daily driver.

Kenny.
 
FalconSedanDelivery":277w72ds said:
is your car a automatic or stick ? , that cam in a 200 with an automatic will be disappointing everywhere but in park , sorry but a 200 is a small engine , I still see the V-8 mindset applied to cam choice and IT IS WRONG if you want a cam change in a automatic equipped 200 and want everything else to be stock , I would choose the smallest cam available over stock , with a stick 2 steps , NOW if you raise the compression to the limit ( say 9-5,10-1 ) that would be then be OK in a stick ( your original cam choice ) but you would still need an aftermarket converter with a 2800 min flash stall ( based on a 200 inch engine ) Also having your Dist recurved is a must , if its a loadamatic , replaced ( sorry they are a poor design )
Click to expand...
I'm sorry but I have a 264/274/112 with a C4, (ported head, mind you) and it is a significant improvement over any stock configuration, even with a 1bbl carb.
I've had the converter modified to a 2200 stall, but I'm not sure that it really matters that much in a daily driver.
Anything higher would not be street friendly.

You have to start somewhere and he can build the engine around the cam.
 
What is your compression ? how much did the converter cost , do you have 1/4 mile times ?, what are you comparing your performance to ? a 1brl setup will have more low end than a poorly tuned 2 brl or 3 1brl conversion , glad you think your combo is good,as it obviously is BUT I still stand by my statement , I just saw the 200 build in Car Craft , and I am sure they think its great ( the pull starts at 4000) its a PRIMEt example of TOO much cam for a DD
 
Wow, if it would that much of a dog why would Mike even bother saying it would work fine with an auto, I also plan on a 2bbl carb and I already have a CI header on my daily that I plan to use. So Im pretty sure it would "breathe" better than stock but you guys are the experts. would a loadomatic be on a 71 engine? it has a vacuum hose going to the dizzy if that tells anything. but it has good response and gets to 60 at about 10 seconds.

Anyone running the 264 112*lc cam with an auto out there?

Lee
 
Ok let me be more clear , Perhaps with all the right parts the cam will probably OK (must be installed correctly and degree for sure ) Mike also ( sorry Mike I e-mailed you on this ) sells the DUI and sadly its NOT a good deal/ part ( for the money ), Almost anyone can install a part, but doing it correctly , and making sure the combo is right takes experience , when in doubt GO SMALL, on a Cam , I looked at the cam rpm range and I have to think they have the rpm ranges wrong , as the lobe sep gets tighter the rpm range drops , and it starts sooner ? , NOT anyway keep in mind these are cams for a 144-250, and if you play it safe the starting rpm is for a 250 and the finish is for a 144 , just to make a point ( from an above post ) you will see that a Comp cam with similar ( actually a smaller cam )http://www.summitracing.com/parts/cca-k31-216-2/overview/make/ford, has the same rpm range ??? , how can that be , simple , The CI Cam rpm range is wrong ,Because its based on V-8 theory, as I said , its your money , your time
 
Stock duration is in the low 190 or below at .050 ,these engines were designed to compete against VW beetles in a 500lb heavier car that is why unless the head is highly modified , or changed shoot for 4500-5000 as a peak if you don't it will have no guts down below , where you drive , pick a combo that suits 85% of your driving style , I like Solid cams , they DO Not need constant lashing ( metallurgy has come a long way since 1965) and they will give more low end grunt and pull higher than a comparable HYD grind , keep the lobe separation at 112-114 if its a 200 or smaller and a Automatic , Sticks can use 110 or 108 ( if its a 250) , if you want to build a Race engine call me , but Ive yet seen this asked on here , Make sure the Ignition is matched to the combo ,( read Dist recurved ) , but as for your original question I would pick http://www.summitracing.com/parts/cca-k ... /make/ford
 
Hey xctasy, i missed out on your articles in earlier posts and from the looks of it the head (pic in previous post) is one off a 170, so someone in the past put it on the 200 block.

Correct me if Im wrong, so these ones flow better? And you can get a machine shop to fit larger valves, for example the ones that Mike sells at CI? Or even bother doing that with a mild build?

If you got any tips or ideas I would love to hear them.

Lee
 
merccomet":3ooceqax said:
Hey xctasy, i missed out on your articles in earlier posts and from the looks of it the head (pic in previous post) is one off a 170, so someone in the past put it on the 200 block.

Correct me if Im wrong, so these ones flow better? And you can get a machine shop to fit larger valves, for example the ones that Mike sells at CI? Or even bother doing that with a mild build?

If you got any tips or ideas I would love to hear them.

Lee
Click to expand...

My 81 Mustang goes just as well with the C1 6090 DE 170 closed chamber cylinder head with nail head valves as it did with the E0 head, even with a 1.3" carb hole verses 1.75", and much smaller intake valves. The 8.9 vs 8.4:1 compression ratio gain with the early 170 log with its 52 cc chamber verses 62 cc or so. The apparent flows are for the open chamber 200 of 105 cfm on cylinder 5, the lowest flowing branch of six, verses the 125 to 128 cfm of the E0 head. The 170 closed chamber head is worth about 125 cfm when decked 50 thou, and more when the valves are opened up. There is a problem with the intake runners, and the later head has a much nicer shot to all six cylinders.

I love the little log because it proves that one doesn't have to go to bigger ports, valves and runners, and that spark character, point to point flow up grades via the right 2100, 2150 Motorcraft or triple 1-bbl is all you need to get a huge hp spike. Or you go big runners an perfect high swirl Classic inlines head.

The 52 cc 170 head is a little like the 57 to 62 cc 302 4v Boss and 57 cc closed chamber 2v 302 Cleveland head used in the 290 hp gross Usa 5.0 Trans AM and then in cooking model form in all 1971 to 1982 Aussie 4.9 liter 188/207/240 hp sedans. It created good compression and exceptional power proportional to capacity, but couldn't carry it in hot conditions, with the engines always running on, and unable to be turned off. The power of the little destroked 302 c was higher specfically than the 351C engines, as it made better spark travel and the closed chamber head worked well with the 5.5 cc relief cuting in the flatop pistons.

I would say the Classic Inlines head does far more than the wildest working on the iron log head, and that Mike would have experimented with the other options, and probably found a best chamber flow was actually down a few cfm total with a closed chamber, but able to make a stuning amount of hp even with less cfm
 
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