Here's what I've been up to today- cutting up the new input shaft for the Lasalle trans, and a shot of the stock one still in the trans for comparison. I've cut the oil spiral off near the bearing, and tapered it up to the keeper groove, and then cut the OD down in the middle to match that of the splines, so I can send it out to have the splines cut back. Next is cutting back the snout and taper, so the whole thing will fit in the bellhousing. Pilot bushing and bearing retainer are done too.
Just wanted to say AWESOME work !!!!! It takes a car guy to see the real details and appreciate them !!! and man you have nailed it !!!!! Great job !!!
Hey 'Sled, if you don't mind, how 'bout letting me know what the splines wind up costing. We're going to need some ourselves.
Tom Staub in Denver will do it for $40. He does a pair of axles for $75, and will do a housing for $75 as well. I sent him my stock Lasalle tailshaft, but I got the shortened trans before he did it, so I put him on hold. Won't be any holding on this input shaft!
OOOOooooooooo!!!! You'll have those step-up jets tuned to perfection! I'm anxious to hear your results.
Cool, good luck. May all of your effort and hard work remain contained in it's apropriate location within the engine.
Hey Moparsled, excellent work. I'm looking forward to hearing this thing... What size headers are those? 1-3/4" They look big!
baseline pulls made tonight, no tuning yet. The carb "hat" adapter I made for the airflow meter was a no-go, so with the emergency help of a friend, I made a new one tonight. At this point we know we're rich, soooooooo...... tuning and more pulls tomorrow. pre-tuning peak h.p. 164.8@4000rpm peak torque 253.6@2250rpm my pie-in-the-sky goal is 200 h.p. , we'll see how close we get. so, an equipment rundown is in order.. 1950 Dodge flathead six (stock rated 103 h.p. @ 3600 rpm) bored .060" (238 c.i.) Egge pistons decked .006" Edgy aluminum head, estimated compression 9.75 to 1 balanced ported, valve guides shortened stock valves with undercut heads valve springs 80 psi @ installed height cam regrind by Schneider 270* adv. duration, .395" lift crankshaft cross-drilled oil pan 2" deeper, right side rail pushed out 1", homemade windage screen oil pressure relief shimmed .050" Edmunds intake, 2 Carter Ball & Ball one barrels ('48 Plymouth) header 1.625" diameter, 36" long primaries, 3" diameter, 12" long collector extension. no water pump, fuel pump, generator Mallory Magspark diual point distributor and transformer Tevco red (translucent) solid core wires Autolite 295 plugs
Hi Moporsled. You know that the mopar flathead 6 is the motor that won the first 500 mile nascar race on a hard surface. I wanted to tell you that when we dynoed my slant 6, we first used a 12 inch collector extension, then when we changed to a 18 inch, it gained 6 hp. Your motor looks really nice. I hope to see it next year at mokan. Joe
I really knew nothing about the Mopar six before I saw your build. That's a neat engine. A 60hp gain is good on any motor.
This is good stuff. I want to see what you can get. I always said I thought I was getting around 175hp with a very similar set up. I don't run it like that anymore cause my Plymouth has baby seats in the back now, but mine was like this: Edmunds head 9 to 1 Edgy reground cam 274 dur. Tattersfield 2 single intake B&B's Mallory MagSpark and dual point distributor home made shorty headers 2" dual exhaust all the way out the back 10" truck clutch
Take the springs out of your step up jets, and try 'er again. Those buggers are the dickens. You'll need them later Hud
Gee, I meant to edit my post somehow - and it appears i deleted it? Make sure your step-up jets are disabled, they are cantankerous buggers to tune and are a horrendous source of rich conditions. But, you'll need them in the final wind-up. I was editing my post to say, I have a pristine EB-7A transmitter - thats 6 cylinders/12 volts. You know how to reach me. Hud
I'm not able to get back over there until Friday, at that point I am going to work on the low speed side of the carbs. I have the blocked off main jets and the UniSyn ready! Truth is, no matter where I end up after tuning, I am satisfied. Even if it doesn't make 200 h.p., it's within reach at this point, so I know I CAN get there. more about the header- All the dimensions of this header were picked pretty much arbitrarily. After doing some research online about header design and dimensions, this header I built is too big in every way. It'll hurt my #'s some, but a redo will have to wait until much later. I also thought the design to be a bit "out of era", but a customer of the machine shop brought me a picture of his Hemi rail circa '61 that had VERY similar headers, so now I don't feel so bad! I have video of the first two pulls, I will link as soon as they're up. Joe Hamby- no- I didn't know that about Nascar/flathead six Mopar- that's cool! thanks!
Mopar, That little devil's making pretty good torque for a 9.75:1 CR engine, especially with that big of a header. I think it would respond with a 1.5 x 32-36 primary with a 2.25-2.5 x 18 collector and about 10-15* more duration @ 0.050. Typically an engine's peak HP is about 1500 rpm above peak TQ. If you raised the peak TQ 1000 rpm I think your HP would easily exceed 200. Very impressive engine! Ron
thanks Ron! the header calculator I used wouldn't accept my stroke #, so I just got as close as I could, it came back with 1.375" x 31.5" primary and 2.5" x 14" collector. Edgy has the pattern for an Isky grind that I really want to use- 280*/.448" I just haven't been able to spend that $ yet. Done this once or twice before, haven't you?
Dang tootin' For his stroke length, he's running a very short overall crank length. He can out-rpm both of us Hudson and GMC dudes. That is until his piston speed frys his Egges. Killler, you aren't even tuned nor synch'd on the carbs - are turning those numbers. Well, I'm on the edge of my seat now, for sure. Hud
Mopar, Done a few....... and some actually worked out the way I planned. Consider your individual cylinder displacement (238/6=39.67 cid). If that was an 8 cylinder the total displacement would be 317 cid (39.67 x 8= 317 cid). That size engine at 5000 rpm would like about a 1.5" header. Granted, we're talking apples vs oranges here but the engine doesn't know. When you consider the rpm drop between gears the midrange torque becomes more important than the max hp. Find your tranny gear ratios and calculate the rpm drop from your max rpm to the rpm it will be after the gear change. Try to tune the cam/header/intake, etc for that rpm range. Of utmost importance is the collector diameter and length. As an example, from 3600 to 5600 rpm our GMC has over 337 lb/ft of TQ with a peak of 346 lb/ft at 4600 rpm. A 4 into 1 header would really help our TQ below 4600 rpm but my partners liked the looks of zoomies. I had the cam ground by Dema Elgin and he missed the TQ peak I requested by just 100 rpm. He hit the HP peak exactly on the nose. Now if I could run a Powerglide with the right converter........... It all comes down to the right combination of parts working together. Two people that dance together all the time look great. Put me in place of the male dancer and I'll guarantee you I'll make us both look like we have 2 left feet. I'm that bad a dancer. The engine looks great and you did a hell of a nice job building your header. I'm sure the 200 HP is there waiting. Ron
had a couple more pulls tonight. No horsepower increase yet. For some reason it will rev great right up to 4k, and then it starts screwing up. A/F was in the 8's, so I pulled the step-up springs, moved the pump shot to the shortest stroke, and put the mixture screws at 1 turn out. A/F is now in the 10-11's up to 3250, and 13's up to 4k. Pulled again, same issue. Closed spark plug gap to .022, and put shims under the plugs to get 'em away from the valves a bit. No change. opened up the point gap from .024 to .027- and got the stumble to move up to 4250. seems we may have an ignition issue! Tomorrow We're going to try changing the Magspark to a traditional dual point, with a regular coil, and I am taking a stock distributor with, as a backup plan. Also- he set the timing at 38* locked. This seems excessive to me- any comments?
Mopar, Ain't dynoing fun.....and informative. Frustrating sometimes too. Definately try more timing. Most of the engines I dyno like 37-42* of timing with the advance locked. Questions: Is .024" the normal point gap? What's the total cfm of your carbs? With the engine shut off and the points closed, what is the voltage on the + side of the coil? Balast resistor? Suggestions: Just use 1 set of points in the dual point distributor. Don't look at the AF ratio except for info. Jet for the best power!!!! As soon as you complete the dyno pull (immediately) smell the air in the dyno room to see if you can smell ANY exhaust. Try a different coil...any kind. Utmost importance: let the engine tell you what it wants...don't try to tell it. I'd love to hear that engine on a dyno pull. Ron
I don't want to step on Ron's toes, but flatheads don't like that much timing. Particularly inlines. If you're going to run a locked timing, start at 22* then move up with sucessive pulls, 38 is kinda excessive. A flathead's cylinder charge is monumentally more turbulent than an OHV and is very sensitive to timing, its really easy to get too high. I foresee you enabling your mechanical advance, but limiting it somewhat to maybe 8-9* Crank degrees, you'll be surprized how responsive those, or any flathead, is to slight timing changes in the upper ranges. Keep us informed, great stuff! Hud
I didn't mention that the reasoning behind the A/F #'s watching was because initially he thought maybe the ignition was having trouble burning the "fat" charge. After leaning it some, and not loosing the stumble, we are now looking at ignition issues. more pulls this morning.
I have partial videos of the first two pulls. I finally remembered to bring the camera home, so I'll see if I can get them up. I'm probably going to wait for more video until the thing will rev right, but boy does it sound good above 4000, and so much better now than in the videos. Also keep in mind that you're not getting "full noise" cuz it's hooked to the exhaust pipe. Lanier had a very busy day today, so only a couple more pulls, but there is some small progress. I changed the Magspark around to a traditional dual point setup, and changed to a regular coil. Timing is 28*. I also straightened up the carb linkage a bit, and dialed the carbs a bit closer together. It now pulls up to 4800, but there it begins to stumble again. More fighting with the ignition is in order. I want 6000 rpm, dammit!!! peak h.p is up to 169.6@4250, same run peak torque 248.9@2750 http://www.youtube.com/watch?v=SFIzQzxhHq8 http://www.youtube.com/watch?v=MyEmUJSyX0Y
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