200 large log head and autolite conversion

coupster

New member
Hello guys, I have a long post and also have some questions for all concerning a 200 large log head and autolite 2 bbl conversion. I am looking for suggestions and I will explain the situation. We purchased a "rebuilt" 200 motor off craigslist, and my intention was to have my 16 year old and I tear it down and reassemble for the experience and knowledge. We would then replace the tired motor in his 68 mustang. The story of the CL motor was it was rebuilt and installed in a falcon, but the car was not roadworthy and they did not want to invest in the car anymore, so sold the motor after running it a short time.
Upon teardown it was very evident that this motor had been rebuilt, as it had fresh gaskets, and small traces of carbon just starting to show on the tops of the pistons. Cam and lifters looked good, barely any visible wear at all. But I did find one pushrod that was bent? So I had to do more investigation.
I found the problem when installing the fuel pump. I noticed an issue with the cam lobe for the fuel pump arm. I could see scarring on the small side of the lobe. After rotating the crank/cam to view the top of the lobe, I could clearly see two grooves cut into the top of the lobe. Someone put the fuel pump on upside down, and ran it that way! Yikes! Now I know why this "rebuilt" motor ended up on craigslist for cheap. That's ok, I expected some issues, and that is part of learning, so my son got some good lessons. Further investigatin showed excellent, fresh bearings on the mains and rods, no scoring and fresh crosshatching on the cylinders. I was confident the bottom end was good, (I know I didn't check the condition/installation of the rings, but felt all was good) so we ordered a new cam. Since Classic inlines was no longer an option...we found a cam kit on amazon from Comp Cams. We got cam, lifters, springs, locks, timing set, umbrella seals and assembly lube. It was a upgrade cam compared to what we had, but not as aggessive as the Clay smith cams from classic inlines. That was Ok with me, again I wanted this for my 16 year old's car...I'm keeping it underpowered on purpose.
So we installed the new cam, lifters,springs, timing set and seals. Motor/trans was installed and (eventually) got it running. Currently we have the single exhaust/factory manifold and the Autolite 1100. It runs good and strong. We put about 200 miles on it this past weekend. We drove to swap meet about 75 miles away. I followed him in my truck in case there were any issues. It did not miss a beat.

At the swap meet I purchased another 200 motor...1980 vintage with large log, large valve, & hardened seats. We plan to convert this large log to a 2bbl Autolite. I will be taking the head to the machine shop for the conversion. What do you all suggest I get done? We have a mild cam, will plan to be adding a dual out header/dual exhaust with the new large log head. I wanted a 3 angle valve job, and back cut the valves...anything else I should add? I thought about port matching/ cleaning up the bowl areas...but I would have to do that work myself, and not really sure what and where to work. I understand port matching but I don't know what areas to work on in the bowls. I do not have the Falcon Six handbook, but do want it. Am I wasting my time cleaning up the head? Is this a noticeable inprovement? I know I said I am trying to stay underpowered, but I do want this motor to be able to breath and perform, not be a dog.

What do you all think and where would you go next?
Let me hear the replies.
Thanks in advance
Coupster

Oh, and an FYI, 68 mustang, 200 six, T-5, duraspark dizzy and box, 5 lug conversion/ 8 inch, & disc brakes. hoping for dual header and 2 bbl conversion soon.
 
Sounds good to me! Looks like you've hit most the bases. Maybe the only other thing to look at would be adjustable rockers or upping the rocker ratio. Yella Terra has the 1.65s listed on their website. Might be a pain getting them shipped to the US...
 
Howdy Back Coupster:

Well done on the Craigslist engine. FYI- The Autolite 1100 in 1968 is down on cfm from previous years, but has no SCV and sends a ported vacuum signal to the DS II distributor. For your combo increasing CFM will be a big help.

What is your goal Compression ratio? What head gasket? I don't recall your location (elevation) but you will want to give some thought to selecting a compression ratio while the head is at the machine shop. Some milling to gain (or regain) static compression ratio will likely be needed.

You didn't give the specs on the cam you are using. Specifically lift. That will determine whether more lift is desirable.

What is the gear ratio in the rear end?

On porting for your uses, I'd suggest focusing on smoothing the combustion chambers and cleaning up the bowls just under the valves. Smooth the transition from as cast to machined. Refining the bowl area will give you the biggest return for your effort.

I hope this is helpful. Keep the info and progress coming.

Adios, David
 
Thanks for the replies, guys, here is a link to the cam kit, and here are the specs:

comp cams K65-236-4
http://www.summitracing.com/parts/cca-k65-236-4

260/260 .440 lift, 110 lobe separation, installed straight up.
It appears to be similar to the Isky cam that Ak Miller used in his "hopping Up the Mustang Six" article I believe, but I could be wrong about that. It is not as hot as the Clay Smith offerings that used to be available on the Classic inlines site. But I digress.

As far as the Compression ratio...It is currently a guess. Since this was a craiglist motor...I really don't know anything about it. I did see that the pistons were 30 over, and slightly dished. I did not measure how far below the deck they were, but they were not flush (maybe 1/8" to 1/4" below the deck). The current head was what the machine shop installed, and it had the stock length pushrod used in the non-adjustable valve train...8.035...I think? I had a pushrod measured by a machine shop to discover they were the stock length. I then ordered a new set and installed them.

The large log head should have an adjustable rocker assembly??, if not, I have one off a 170 that I can use...But will have to verify it's worthiness first. I have the permatex/permatorque head gasket currently, but may use something a little thinner to help with compression when going to the large log. I was thinking of milling the head, but unsure how to verify exactly what I need to take off?

I guess I will really need help in the area of compression ratio, and valve train geometry/compatibility.

I know the valve springs in this kit are not as tight as 289/ or 302 springs, and was thinking about upgrading this on the large log as well?
What about the exhaust valve size? Is the 1.50 valve size worth the trouble over the 1.35 that I think are in the large log head?

Again thanks for all help in advance,
Coupster
 
David, I missed a few of your questions so here goes: I am in central texas at an elevation of about 800 feet, so not really much of a factor unless you want to talk about humidity! You are correct on the 68 1100-but I have a worked-over 1100 from a 67 with the SCV modified-(read blocked off)...I did not drill out and plug passages, but did pack them full of RTV to test the process out...and it has worked well so far for over a year. Vacuum for spark advance still comes off carb as factory, but that passage is "modified" too. My desire for a 2bbl is rooted in the fact that I have been thru 3 other 1100's before I finally got one that would tune and run properly. I have had several ford products w/ the 2100 and it is pretty much idiot proof-(IMHO)- despite my many attempts to prove otherwise. Also, I think I want to use a cable type accelerator pedal and get rid of the bellcrank/bars arrangement.
Rear end gear currently is a Vibrado 3.00 open-it numbs your butt at about 60 MPH, but smooths out above 70. I will be addressing that issue in the future, but that may require an upgrade of gears to 3:40-3:55 if I have to go into the pumpkin. The T-5 is a WC V8 so overdrive is a consideration in the gearing for sure.

As far as the increased ratio rockers...it's an idea I like...not sure how all of the changes will work out with milling, adding adjustable valvetrain, and going with the thinnest possible gasket...(Victor I think?) but that is what I was thinking I would need to do. The possiblity of upgraded rockers and larger valves sounds good and may be feasible if the $ isn't too much. I have to get quoted on the valve job/conversion work first.

More food for thought...keep it coming guys!
 
PM Does10s to find out if he has any of the 1.6 rockers. Otherwise the Yella Terra 1.65s are available here:

http://store.yellaterra.com.au/ford-inl ... ef-st2014/

I just don't know how shipping would work out. You're still looking at probably $600 or so for them (after adjusting for Aussie -> US currency and throwing in shipping). I would still pull the adjustable one off of your 170. Not that it'll give you any more go (same ratio) but at least your train will be tighter.

Here's your valves:

http://www.sivalves.com/ocdomestic_valvesps_ford.html

It looks like you just have to call these guys. Does10s does have some valves left and he's supposed to be getting back to me in the near future on price and whatnot. He's out of town right now but you might ping him for a set of 1.5" exhaust since you've already got the intakes.
 
Howdy Back All:

Your gearing plans sound right on. I'd for go the 1.6:1 ratio rocker arms. With a cam lift of .440" it is probably already exceeding the flow capabilities of your head. The expense is high with a marginal return in performance. on the 170 adjustable rockers you have make sure to clean the inside of the shaft thoroughly as well as making sure the oil holes in the rocker arms are completely open.

Given your cam and proposed gearing, I'd suggest a goal CR of 9.5 to 9.75:1.You may need a tank of 95-97 octane gas in the heat an high humidity of the summer, but will probably get along with 87 octane otherwise. I'm assuming that you have your distributor recurved for your combo.

I love the Autolite 2100s too. I used a 108 on my 250. My brother has a 121 on his hot 200. The cable linkage is a "No Brainer" too.

It will be a good ideal to cc your chambers to accurately determine how much you will need to mill. It's messy but it is the only accurate way to know what you have and what will be needed to obtain your goal CR.

Keep it coming.

Adios, David
 
Thanks for the confirmation David, it's nice to hear that I am headed in the right direction. This 6 cylinder stuff is all new to me, but we have been working on this car for about 4-5 years as a Father/Son project and the experience has been great. I have spent great amounts of time reading and researching, and am eager to get this car running in tip-top shape. We are getting close now, and we are down to the fun part. We have made our changes/upgrades in phases, and my son and I have gained alot of knowledge in the process.

So you suggest 1.6 rockers. I will look into that. I guess I need to figure out how to verify my combustion chamber sizes. I understand how the head is measured or CC'd but not sure how that would apply to sizing up the cylinder area that is below the deck and above the piston? How do you measure that portion? Must be important to the compression ratio, I assume. I am sure you guys will have an answer. I will discuss it thoroughly with the machinist to get his take on it.

Also I have a few 2100's on the shelf, I know a 1.08 is there, and maybe 1.21? I think. Will have to verify them, as well.

Gears will be in the future, as Air conditioning may be moved higher on the list if this heat doesn't let up soon.
Thanks for listening and helping, all is appreciated
Coupster.
 
As far as cc'ing the chambers goes, head to your local farm supply store. I haven't measured the volume of mine yet (currently doing a port/polish effort myself) but this is what I bought.

1 small sheet plexiglass
40 cc syringe
Marvel Mystery oil
white lithium grease

1) Cut the plexiglass down to a square big enough to cover the combustion chamber (4" by 4" maybe? just double check).
2) Drill a hole on one end of the square that is large enough for the head of the syringe. I chamfered the hole just a bit for ease of use. Make sure the hole is near the edge of the chamber so that you reduce the chance of an airbubble getting trapped.
3) Grease up the back side of an intake and exhaust valve and drop them in. Swirl them around a bit to make sure you get a seal.
4) Install a spark plug. Use the exact same sized one you plan on installing.
5) Tilt the head ever so slightly that one edge of the chamber is above the other (tryin to reduce air bubbles).
6) Put a bead of grease around the outside edge of the combustion chamber and place the feed hole on the top as close to the center edge of the chamber.
7) Start pumpin in the oil, keeping track of how much you've put in.

I haven't done this yet, but I worked it out in my head and am just going to assume it'll all come out as planned. :beer:

This won't be exact, but I'm not building an engine for NASCAR either.... I'm going to try to match to 1/4 cc if possible. It'll just depend on the gradient of the measurement marks on my syringe. I plan on measuring all 6 first, finding the largest one, then make a determination as to whether or not the difference of the different chambers is worth the hassle of grind->check->grind->check->etc.

Quick math I just did showed the following. I would think (seat of my pants SWAG) that a threshold of 0.1 C/R difference per cylinder would be acceptable. Hopefully someone will correct me if I'm way out of bed here though. Too be honest though, 0.5 cc seems like a lot of material to remove, so I should be pretty close already. Even 0.25 material will probably feel like I'm sanding forever.

Volume_Diff C/R Hit
0.25 cc 0.02 <- Negligible
0.5 cc 0.05 <- Negligible
0.75 cc 0.08 < - Borderline too much
1 cc 0.11 < - Too much
 
hOwdy Back:

Oops, I meant "Forego". No, I'd recommend that you use the stock OEM 170 adjustable rockers you have and Forego the expense to gain another .030" of lift that will not offer much in added performance. sorry for the confusion.

Bobcat has you lined out of the ccing process.

Keep it coming.

Adios, David
 
Oh, I got it now, skip the rocker upgrade, easy enough. Thanks David.
Bobcat, thank you for the great explanation on CC'ing the head. I think I can handle that job. Do you by chance have any pics of your port and polish job? That would be good to see.
I appreciate all the help guys,
Coupster
 
I haven't taken any new pictures but I've been a little slow on progress lately. Here is what I've gotten uplated so far.

http://s1361.photobucket.com/user/cr_bo ... t=3&page=1

And this is the thread I've been posting my progress on.

viewtopic.php?f=5&t=72937

I'll try to snap a pic of the plexiglass plate that I cut and add that into the library. So far it hasn't been too bad. I'm getting better with each chamber. It's just takes some practice with the grinder and dremel. Only thing I've managed to screw up so far is to break off an easy out on one of the old header bolts. :beer:
 
Fwiw, I'll add that it helped me to use a graduated cylinder or flask when doing the cc'ing. I got a discrepancy using a syringe alone. I found it was easier and more accurate to fill a 100ml flask with say 90cc's/ml, draw from it, then shoot any remaining fluid back into the flask after the chamber is filled and do the math on what you took out.
 
An Engineer is someone, who does for 10 dollars what any damn fool can do for 100.

The advice you have been given is pretty good. The 1.6 ratio is the one to have. 1.73:1, 1.8 and then 1.9:1 were the stock later model ratios overhead cam 3.2 liter versions of these engines used...it wasn't too much, and those engines were at the 100 rear wheel horspower level with T5 gearboxes, 3.2 axle ratios, 0.70 top gears. The little log head will just lap it up.


Its at about 490 thou lift with a shaved head that you might run into piston to valve contact, even a 50 thou shaved E0 head on a stock 200 block with 1.6:1 rockers will be country miles away from that.







Stanyon and
Crosley have the whole direct mount 2-barrel thing totally worked out for the D7 head,


Crolsey's old Falcon does flat 15 second quarter miles with a 274 cam, D7 head and direct mount 4412 500 cfm carb. That's with an automatic which probably does 145 rear wheel horse power and 205 hp at the flywheel tops. According to Ak Miller and about 45 years of imperical results on a proper chassis dyno:-

With the same rolling resistance from the weight of the car,
and its four wheels on the road,

a manual will loose as little as 26% of its power to the rear wheels,
and an automatic, more than 40% always. When measured at a drag strip, the losses are always less because shock loaded automatic or stick shifted drag racer will show less than 15% power loss on a flywheel dyno figure.


Cutting edge modifications have varied over the years, but a direct mount log 2-bbl will get you results.

In Horsin' around with the Mustang Six, Ak Millers big 1-bbl Autolite 1101 conversion took things up to about 100 rear wheel horsepower with headers and a 260 degree Isky cam in 1967. He then went to the rather more complicated route of multiple carbs, that was 1967 cutting edge, 115 to 125 rear wheel hp with a manual transmission.
In 1970 to 1972, and Triple carb Offenhauser adaptors, and he got aproximately the same 100 to 125 rear wheel power levels on his 200 and 250 cubic inch Maverick conversions.

By 1982, Ak found found a little old Fox 255 4.2 or 302 5.0 2150 Motorcraft as a direct mount would do even better. They were 115 to 140 flywheel hp carbs in those cars. The summary article was Jay Storers, and Invectivus has links to it here.

In terms of the best bang per buck, Ak Miller found in 1975 a stock log head with just a 2-bbl carb and a turbo would take you past the 150 rear wheel hp level with no other modifications. He started finding that out in 1971 with his work as an Impco Propane technician. His landmark engineering won the Baja 1000 that year with a production Landcruiser 4.2 liter I6 and just a few propane tanks an a turbo. The Hugh Mc Innes Turbocharging book describes the schematic.


In 2015, a direct mount 2-bbl gasoline Auotolie or Motorcraft log conversion will easily take you to the 115 to 125 rear wheel horspower, exactly the same the old twin SU HD8, Harley Davidson SS or quad Honda Kehin carbs did with headers back then.





JackFish has an example of the whole cleaned up combustion chamber.

These are the D7 heads which are similar to, but not exactly the same as the E0 head.


The EO head could use a head shave from its nominal capacity of 60 cc down to the ideal 51.5 cc or less. Removing 60 thou takes less than 8.5 ccs off the block. Decking the head 60 tou will bring the camber cc down to about 52 cc in most cases.

Then you can use whatever Autolite 2100 2-bbl you can find.


I'll post the links soon.
 
viewtopic.php?f=1&t=72198&p=554386#p554386
stanyon":gy5k7eza said:
Milling or machining the head for a direst mount for the Weber really isn't that hard, a couple of hours is what it took me . Search Milling Intake.

http://vintage-vans.forumotion.com/t394 ... og-milling
and http://sport.motiontopic.net/3554281394 ... og-milling

Crosley's http://fordsix.com/forum/viewtopic.php? ... 76#p440076


http://fordsix.com/forum/viewtopic.php? ... 96#p546096

JackFish":gy5k7eza said:
xctasy":gy5k7eza said:
and picture is, I think, Jack Fishes D8 head.
I saw the pic and thought gee that looks like mine...
3de6dc2b-9dbf-43f3-95db-542db0e2917d_zpsd3572813.jpg
 
Awesome information guys, I really appreciate all the reading...I will try to digest everything and see what I have. We did install the header and dual exhaust this past weekend. It sounds really, really nice. We went with 2" pipe, and glasspaks...for the old school sound, also have an "h" pipe and dual tips out the back. My boy is pumped about how tough it sounds compared to the old single pipe. Next we have to decide about the head upgrade, but that will be in the future at this point. Time to do some driving. It runs really well with 1100, with a 64 jet. We also added a fresh 2 core V8 radiator, and a 180* thermostat. Runs nice and cool at 70 mph and 105* degrees outside. Gotta get the A/C going, but will have to mod the original A/C bracket again. But I really appreciate all the feedback. Thanks again.
 
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