I had intended to use my 37-48 styled Super dual intake on my 50 8BA. Is it a good idea to close off the road draft tube hole on these engines? Are there any steps I should do before attaching the earlier styled intake? I looked around for past discussions for this subject but didn't come up with any info on it other than the discussions regarding the pcv hookups. I am not, at all, knowledgable on the 8BA's. Please forgive me for asking some stupid questions. (your neighborhood 8BA newbee)
I think the PCV threads came about in reference to your question. Most people feel you need to replace the road draft system on the 8BA with some type of PCV system if you use the early manifold. How you do that is up for lots of discussion. You may want to reread them and decide which PCV solution you like best.
Then, I guess the question here would be.. I understand the reason for the installation and obviously Henry thought it was worth the change. But if the pre-49 engines did not have a road draft tube, then what would the effect be to close this off on a 8BA? Are the newer engines designed in a different way to vent off the gasses that the regular oil fill vent would not be effective? If I would make a decision to use the older style intake. Will I have to close the vent hole at the oil galley? Another stupid question.... I am on a roll If the vented hole is not closed off at the galley, then would the unvented intake allow for these gasses to go in for combustion?
[ QUOTE ] Are the newer engines designed in a different way to vent off the gasses that the regular oil fill vent would not be effective? If the vented hole is not closed off at the galley, then would the unvented intake allow for these gasses to go in for combustion? [/ QUOTE ] Yes they are different. Don't think of any breather system as a vent to relieve pressure. Think of it as pathway through the engine that the fresh air takes to remove moisture and blow by gasses. There is a definate intake for the air (the filler tube for either engine) and a definate exhaust for the gasses (the road draft tube or PCV valve). The 59A had a small road draft type of vent built into the oil pan. The 8BA was an improvement on that. The tube in the valley of the 8BA is part of that pathway through the engine. Some guys use that tube to locate a PCV valve inside the engine. Check out those PCV threads. Lots of good information there.
The old engine has an vent at the "rim" of the oilpan(right side?), and the roaddraft is doing the evacuating here to. The air enter at the back at the fuelpumpstand where you fill the oil. The big news with the 8Ba was the move of the oil filler hole,so it would be easier to add a quart if needed. and then they added the roaddraft tube. And my theory is that it was done to prevent oil leakage(mist) down att the oilpan. The air on the 8Ba is entering at the oil filler tube. and exit thru the roaddraft tube.So now to your question. There is three ways you can go, in my opinion (actually only one ). 1: Add some kind of pcv solution, that is described here at the Hamb 2: Convert your 8 Ba to 59Ab by adding an 59Ab type ventilator to the 8BA oilpan ( idont think you can ´change oilpans. I dont know if anyone done this thou. 3: Remove the 8bA roaddraft tube and mount your 59Ab manifold, and drive it. I guess you can get away with it if you change oil regulary, DONT plug the oil filler you need air to be able to enter and leave the engine.
Petejoe. I just did what you describe on my own 8BA using a Fenton 2X2. All you need to do is retain the breather/oil filler tube on top of the fuel pump stand that was on the early manifold. PCV is not necessary. I used an electric fuel pump so I made a breather tube adapter out of 1/2 in. aluminum. If you close off the fuel pump hole and run without a breather, you can pressurize the crankcase and blow up the pan like a balloon. There is an aftermarket breather that fits on the pan (Flathead Jack), but I've never seen a stock one on the pan. Doesn't mean there wasn't one on some models. I think that the only reason that Ford moved the rear breather to the front and incorporated a down draft tube is to keep the crankcase fumes out of the cockpit. No more stinky poo ol' ford. Regards, pigpen
That clears up my understanding. Thanks guys for your patience! I am just making plans for this winter project and mental plans of my options. I may just go with the PCV installation, since this will provide a good opportunity.
Here is a picture of the lower ventilator on a 59AB (instead of the 8BA roaddraft tube). And there is a corresponding hole in the block. and on the 8BA they had change the casting so the hole is in the oil gallery. So even if there is hundre maybe thousands examples of guys change th e8ba manifold to a 59 ab type without blowing up anything. The engine will work for quite a long time with only one open air opening. Why not try to keep the original function at least.
I also took a 8BA and changed everything over to resemble an early block, I decided to keep the road draft tube on an early intake by simply turning the fuel pump stand bacwards and cuting tubing and a flange to mount, and inturn keeping the top breather so as to add oil and such. I dont have a pic of it but I stole the idea from the rodders journal from a pic of the restored Alexander Bros pick-up truck.
I am glad that you asked this question, I am a flathead newbie too. I have an early thickstun intake for my late flathead and never even gave the road draft a thought, I had only heard to check the fuel pump rod length when using a stock pump. Thanks for asking the dumb questions that some of us weren't even smart enough to ask! Tim
Keep in mind a good system really should have an in and an out. The road tube and the equivalent draft protrusion on the '35-48 pan is the out, the breather at the back (or up front on late engines, isolated from the draft area) is the in, only becoming an out on engines with clogs or lots of blowby. The PCV is the out, and somewhat more reliable than roaddraft, especially when idling. To replicate a stock flathead PCV in this crossbreed situation, drill a hole on the right front of the gen bulge in your manifold for a PCV from an engine a bit smaller than yours, stick the pcv in, and drop a rubber hose into the vertical pipe inside. Drill&tap a blind pipe threaded hole under either front or rear center of area right below a carb and then drill a small hole from the bottom of that into each barrel. Note that this can be routed pretty inconspicuously.
I have a 59AB under the bench that I haven't messed with much yet; only the 8BA. Didn't notice the pan vent. You learn something new every day (hopefully). Thanks a lot. pigpen
[ QUOTE ] I have a 59AB under the bench that I haven't messed with much yet; only the 8BA. Didn't notice the pan vent. You learn something new every day (hopefully). Thanks a lot. pigpen [/ QUOTE ] It's easy to find the pan vent after trying to track down an "exhaust leak" coming from under the car. I welded up every possible (non-existant) exhaust crack/hole in my exhaust system, only to find afterwards that there's this hole in the oil pan spewing smoke because of blow-by from old rings... I had only owned an 8BA up till then. Talk about learning the hard way! Mike
I've been doing a lot of that "hard way learning" myself lately. Ever see a hollow Johnson style solid lifter collapse? The metal was sort of pushed aside like a new tub of butter you just drug a knife accross; screwed up the new Max One cam pretty good too. The lifters were supposed to be Isky; not. Overseas fakes. Hor Rod and Custom Supply in Fla. told me the big lie and sent me another set of fakes as a replacement. They did replace the cam also but only because I didn't "bust their balls". Isky says they don't sell their lifters to HRACS, only their cams and springs. Keep on flatheadin', pigpen
Something else to think about if you havent. If your working with a bare 8ba block, drill & tap it for the extra intake mounting holes that the early intake has. That way your finished motor wont look like it has bolts missing.
The Jalopy Journal
