Which motor?

I talked to you guy's earlier about the jeep 2.5 or pinto engine swap into my 3a. Well, the more I look at it, I sorta like the way the old flat head looks in there. There's oil in the motor, but haven't tried to turn it over as I haven't brought it home yet. If the engine isn't locked up, would you guy's keep the flat head or update to a newer 4 banger? I'm sorta tore now. I wanted a newer motor so I could get 55-60 mph out of it, but thats really not so important here in the country. If it only goes 45 or 50 would be allright with me. With a rebuild and a couple performance mods like a header and cam, plus maybe MSD or jaccobs, should be fast enough for these back country roads or trips into the small towns around. Opinions please, what would you guy's do, keep the flat head or upgrade to the pinto? I trust your knowledge and advice. "Thanks":?

 

If it was mine and it had the flathead I'd keep the flathead. I just aquired a CJ2A project that already has a Pinto engine in it so it will stay Pinto powered. I am however considering converting the L134 in our '45 to fuel injection using 1990 YJ components.

 

Wendell, I will ALWAYS say keep it stock. Personally, I think that 60 is too fast for the old flatties. With 50-60 year old parts in there, who knows what is going to let go at the most inconvenient time

I feel your pain about wanting to get up to speed on the highway. Around here, all roads out of town are at least 65 mph and if you're not doing that, you're a hazard!

It all comes down to what YOU want. If your Jeep will do what you want with the L-Head in there, then why not keep it?

Best of luck

Doug

 

The flathead Willys engine can be built to put out 80 horses. Or more.

Shaving the head and block (while keeping the piston top below the deck of the block) and CCing the combustion chanbers to raise the compression from 6:1 to 8:1 will do that. Offy manifolds with multiple carbs and headers so it will breath better. If you can find one or remanufacture and old head to match, the Willy-Willy head from Australia makes a difference.monkeys

 

I seen where clifford makes a header for it, but haven't found any other performace parts. I lowered my expectations, 45-50 mph would be good. 80 hp with the steep gears it has would be pretty peppy, at least for a rig over 50 years old. You say raising the compresion with some head work will get you some extra ponies huh? How about boring, how much room is there to go over sized on the pistons? I know my engine will need rebuilt any way. The more I think about, having the flat head would be cool. Is there a system for it to do away with the points? I don't even remember how to set points, or do I want to ha ha.

 

Theres lots of room to bore. Mine whas .04 over when i got it and i boored it to .06 over I think thats the measurements? Theres definatly a high nostalgia factor with the flathead. i considered swaping mine out but im glad i didnt

 

Check out Pertronix. They make a module that will replace the points. I don't have one myself, but was thinking on getting one. http://www.pertronix.com/default.aspx

Get your distributor model and contact them.

 

Steve Lane (w3srl) has a very nice cj2a that has electronic ignition and had the motor rebuilt several years ago. He is putting (2) 1 bbl carbs on it sometime soon. The engine runs very good. I think that you can actually bore the old flat heads .100 over or more, seems to me I saw .120 over pistons somewhere. I would not go more than .060 over right off the bat. Clifford will grind you a cam if you send them the old one for a blank. That with a header, a 2bbl or (2) 1 bbls with a shaved head, electronic ignition with an MSD box should really wake up the motor.

 

Thanks for the imput, if the 134 can be saved, it will. I love the whine they make when your rolling them out. I love listening to the old jeeps on mash.

 

If I were determined to keep the L134 I'd look at old hot rod magazines and hop-up books for information about hop-ups for the Ford flathead engines. The 4 C's still apply - Cam, Carburetion, Cubic inches, and Compression. If you bore out the block 0.125" to 3.25" that will give you an 8% increase in displacement to 145 cid and roughly the same increase in power. Custom pistons and sleeves would provide even more displacement. Compression will also go up with increasing displacement by roughly the same percentage. Look to the hot rod literature to see what compression ratios are realistic for a flathead, and plane/relieve the head accordingly. Carburetion means breathing in general, so I'd look at the porting and polishing appropriate to a flathead engine - don't know if larger valves are an option, but I'd look into it. Cam has already been mentioned. I'd think you could increase your power by about 50% from stock with the right upgrades. However, it seems clear to me that I'd have to be more in love with the L134 than with my money to make all this happen. It'd be a cool project though, and fun to do. hth!


BTW - I presume much of that whine is from the gear drive, but the straight-cut transmission gears in 1st also contribute.

 

I'm not going to get crazy with it. I'm sure I'll need to rebiuld the engine anyway. So it can get bored out a little with some head work. A cam and header, plus MSD will be good enough. Does anyone make a 2 barrel intake for it? With increased flow, it will need a little more fuel to be really effective. I had an 88 suzukie samari and it had a 60 hp motor. It would do 55 -60 with the wind to your back, if you were heading into the wind it would do 50 mph. However it only had 3:73 gears. If it would of had 4:10's or 4:30's it would of held speed a little better instaed of constantly running out of power in 5th gear. The willys is a restoration vehicle, so 45-50 would be great for what it will get used for. Power is no problem off road, with the gearing it has, in low range it will climb tree's.

 

The sound of the jeeps in M*A*S*H and other places is from the cooling fan. Very recognizable, and surely a real part of the jeep flathead (and F-head) experience! Almost as much so, is the sound of the brake pedal screeching against the floor panel. BW

 

i couldn't agree more! i'll add one too: 1st gear in the t90 when pulling away from a stop.. classic jeep sound!