Have a 39 Ford pickup with 42 Merc 100 hp flathead and was considering either using the existing manifolds and making it a dual exhaust or getting Fenton headers. Of coarse can do the duals much cheaper and per my understanding, headers wont really add any performance but might lower temp a bit so what do you guys think? Btw, my plan for future is to add a dual carb intake and Aluminum heads , mild cam and might go through whole engine if needed. Right now I am just going to enjoy it before any major work.
I like Red's headers. They're well made, look decent and fit well, and they're cheaper than the Fenton cast ones.
Price the many sets of tubing headers on the market & compare to the repop Fenton. Some of the really old fellers said they were best at reducing heat ..
I bought the Red's headers and after burn in was done on the new flathead I had them ceramic coated which is great for heat and looks nice.
So far it is unanimous headers vs plain ole dual pipes. I saw several whom heralded Fenton , some say they run cooler that tube s which makes sense but ceramic coated Reds would probably run pretty cool. As far as cost, Reds ceramic coated would be $450.00 , Fentons from Speedway are $300.00 .
True, but on a fresh build I would suggest having them coated after burn in so as not to cook the finish off of them. I have made that error before.
Some of the really oldtimers claim there is no advantage going to duals on a stock engine. It’s something about the crossover helps speed exhaust gas evacuation. It’s a fact that flatheads were made for Dearborn winters. They can struggle in sticky Southern high humidity heat when heat transfer is not the best. It’s more of a humid thing than heat. A Flathead in good condition, with good clearances, oil, oil pressure, water pumps, clear clean block, clear clean radiator, good belts tuned and timed right should do fine. No pre 1962 designed Ford Engine likes hot summers and stop and go traffic over baking pavement. They much much prefer to cruise around at 45-50. That’s fast enough for the wind to do it’s job but not too fast to tax the engine. Of course your results may vary. Stop and go traffic it will not let it cool down like it wants to. It needs some open road between lights. At the light, the temps creep up, oil pressure goes down. This can be worrisome but it’s not a modern engine. The oil pressure gauge on my 8RT was like a Tach gauge. 5lbs or so at idle.... get on the gas...it shot back up there. Keep in mind a stock Flathead can idle at a low low RPM. Just playing around, I have idled one down so low the fan was barely turning. I felt as long as I had 10lbs per 1000 rpm....I was fine. My experience with tube headers is they increase temps with an OHV V8. Now with Flatheads this may be different somewhat if you use the smaller type of headers. Trucks may call for a specific header for clearance. I know it can make a difference with a F1. This is what I would do.... I would ease into it. I would take short trips. I would keep an eye on temps and pressure. I would familiarize my self in how it drives. I would make sure the brakes were perfect before each trip. If she gets too hot.. Stop and let her cool. Carry extra water. This should go without saying but let her cool before checking the water. This has been long so I’ll wrap it up.... It’s 80 years old. Until you know it, go through a checklist... check everything. It’s not a new Tacoma. I would drive for awhile like it is. I would baby it... get to know it. Make sure it’s right stock then build up on that. The fist step in hot ridding is making sure it’s perfect and tuned well stock. Everything is based on that. That’s your foundation.
F -ONE , I have one of those infrared thermo's and my temp has been between 165 and 180 reading right at or around the spark plug on short trips running around town . I took readings at about every point on or around the engine, radiator , water pumps and the highest temps were at or near spark plug except near the exhaust manifolds. Been up to about 45 or 50 mph only a couple of times, I think it runs pretty cool so far and those #'S were taken during 90 to 95 degree , very humid South Carolina days recently. Cant remember exact oil pressure ( forget what the gauge says) but it has been on the upper end so far. I have s suspicion that this engine was rebuilt some time ago. The story from the lady whom I actually bought it from ( was a consignment sale) said her husband whom has since died did all sorts of work on several vehicles a few years ago including another 39 truck and a 40 truck. I saw the other trucks and they were very solid truck so the guy had an eye for good solid vehicles. Anyway after crawling under the truck about a hundred times , checking everything out I noticed the oil pan is a different color than the engine and the gasket looks fairly fresh.,not recent fresh but from my experience and what I have observed and done of the past 45 plus years it looks like what you might see on an engine that had been rebuilt in the last 5 to 10 years . I know the different color on oil pan really means nothing but it did cause me to take a good look at the gasket or the bit of the gasket you can generally see. The engine does not smoke a bit , still gonna check compression but loaned my tool to someone who has not returned it .Oh and as far as the tube headers , I am not sure but I tend to agree, seems I have burn hands or fingers more on tube headers that I have on cast Iron manifolds over the years.
Said no hot rodder EVER! I'm just givin you crap buddy but seriously if young men had uttered such a statement this website would be about knittin and we would all be filthy rich...or drunks.
The only reason people still run flatheads is they look cool/ And in an exposed engine stock mainfolds converted to duals don't look good. I would buy Fentons.
One thing Fenton's have over regular tube headers is longevity. I installed a set of Fenton's on my '51 when I got it in 1987. Two years ago, when I installed a new engine, an inspection of the exhaust system showed everything to be in excellent condition, even after 30 years of regular use. If you're going to keep your vehicle, go with the Fenton's. Otherwise, I'd stick to stock manifolds with dual exhaust. (Some vehicles deserve to be treated better than others.)
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