Joel Posted August 20, 2015 Report Share Posted August 20, 2015 I want to replace the flat six in my 49 dodge and was wondering what I should get for more speed and more power thanks Quote Link to comment Share on other sites More sharing options...
HanksB3B Posted August 20, 2015 Report Share Posted August 20, 2015 Something Mopar not a 350 Chevy Keep it in the family, Hank Quote Link to comment Share on other sites More sharing options...
NiftyFifty Posted August 20, 2015 Report Share Posted August 20, 2015 I would look at all the build threads and judge the swap from there. It's nice to drop in a BB 383/440, but their also not the cheapest engine to build. A Chevy 350 is cheap like dirt, as is the TH350 to put behind it, but yes..it's a slap in the face to the MOPAR gods. Lol Quote Link to comment Share on other sites More sharing options...
jeffsunzeri Posted August 20, 2015 Report Share Posted August 20, 2015 (edited) I want to replace the flat six in my 49 dodge and was wondering what I should get for more speed and more power thanks Least painful in both dollars and effort will be to replace the short 218/230 with a long 251/265. Take a little care in building the 265 and you'll end up with around 270 cubic inches, and around 160 HP+ with a great torque range. This will be close to double the original HP, and on par with a healthy 318 V-8 with a 2 bbl. Edited August 20, 2015 by jeffsunzeri 2 Quote Link to comment Share on other sites More sharing options...
JBNeal Posted August 20, 2015 Report Share Posted August 20, 2015 When doing power upgrades, the entire package has to be considered to execute a fully functional & safe driving experience. This truck was designed around the 23" flatheads; the 25" flatheads can fit with little modifications to the frame, firewall, brakes, etc. as compared to dropping in a V-block. With more power brings the need for more braking & better handling, and this can spiral upwards to where a chassis swap would be cheaper & more effective than modifying the B-series frame, etc. I have not run the numbers, but from appearances, putting the B-series sheet metal on the 1st gen. Dakota rolling chassis seems to be the cheapest & most effective way to get more power & have a daily driver to boot. My personal preference is to keep a flathead under the B-series hood, just to enhance the wow-factor of the rare Pilot-House truck. But bottom line, do whatever you want to do with your truck...it's your dime, after all 1 Quote Link to comment Share on other sites More sharing options...
Reg Evans Posted August 20, 2015 Report Share Posted August 20, 2015 When I got my 52 1/2 ton it had no engine so I installed a Chrysler 251. It's ~2" longer than the original 218 so I shaved the head about .050, moved the radiator forward,installed 2" tabs on the front motor mounts to reach back to the mounting holes, and nipped a bit off the front cross member to clear the oil pan. I also installed a 66 T-Bird rear end w/3.0 ratio so I could keep up with traffic on the freeway. My truck has a 4 speed floor shifter from the factory with granny low and even with the 3.0 rear I don't ever need to use 1st gear. 2 Quote Link to comment Share on other sites More sharing options...
wayfarer Posted August 20, 2015 Report Share Posted August 20, 2015 I'll disagree a little with JB Neal...a v-8 swap does not have to be complicated or overly expensive. Certainly does not require a frame swap... Look at this: http://p15-d24.com/topic/18782-dans-hemi-swap-project/ There is plenty of room for a A-LA engine (maybe even a B-RB) as Dan's project shows so well with the 354 Hemi. The biggest issues will be whether or not you need/want to keep the existing trans and the 'things' currently attached to the bellhousing. If you are also planning upgrades to the rear axle (required with a trans swap) or front disc brakes then a v-8 swap may be the next logical step. Yup, your money, your choices..... Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted August 20, 2015 Report Share Posted August 20, 2015 JB has it right in that you need to consider the entire build and planned use of vehicle....as to cost..that is just a matter of resourcefulness for the most part... 1 Quote Link to comment Share on other sites More sharing options...
NiftyFifty Posted August 20, 2015 Report Share Posted August 20, 2015 If your going daily cruiser or long haul show truck, my recommendation is V8, I'm regretting more and more not doing that swap right from the start on my truck, and including a front IFS as well. My issue now is I've created a money monster, and to swap to a V8 now means dumping a lot of time and effort and parts down the tube. I'm pushing now to just build my car up and finish it instead. I also don't believe that getting up to 160hp out of a 251 is a cheap and economical process, it's more money to build a 251, then it is a SBC, and at 160, you still have some of the issues that can't be avoided with a flathead 6 Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted August 20, 2015 Report Share Posted August 20, 2015 If your going daily cruiser or long haul show truck, my recommendation is V8, I'm regretting more and more not doing that swap right from the start on my truck, and including a front IFS as well. My issue now is I've created a money monster, and to swap to a V8 now means dumping a lot of time and effort and parts down the tube. I'm pushing now to just build my car up and finish it instead. I also don't believe that getting up to 160hp out of a 251 is a cheap and economical process, it's more money to build a 251, then it is a SBC, and at 160, you still have some of the issues that can't be avoided with a flathead 6 that very observation is often hard for some to arrive at. Granted the mystique of a hopped flattie is a true rush..but at a point you trading off reliability and maintainability for so little HP in return. I know many hate this response...but not every vehicle out there is a candidate for a factory points car...I don't even look for them to start with..that way, no remorse on a cut and weld...some of the cars I get folks here would consider less than a parts car...but in this neck of the woods...you don't have a lot to pick from to start with..and again, to me, the fun is the build... Quote Link to comment Share on other sites More sharing options...
William Davey Posted August 21, 2015 Report Share Posted August 21, 2015 Joel, I have NOT done a swap to more power and here's why. I had a line on a freshly rebuilt running 354 Hemi for $5k, then add a built torqueflite or 904 for another $3K, and Mopar 8.75 diff for another $1k. Better box the frame and add Fatman independent front suspension ($3k) and power disc brakes all around ($1k). While the body is off the frame might as well paint it and the box too ($5k minimum). New paint makes the old interior look crappy so better put a new interior ($3K), gotta have new wheels and tires too ($2k). Add a few bucks for contingencies like A/C and it's $30K. And when it's all done will it a) be too nice to drive or be too scary fast to drive. I'm not criticizing those that have done similar builds like Albolton on this forum. He has a beautiful truck and it runs like a scalded dog, but I don't have the tools or ability to do all this work myself and I don't have $30k to spend on a truck that's just a summer hobby. Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted August 21, 2015 Report Share Posted August 21, 2015 Man's got to know his limitations...... that could be a good tag line for a movie....... 2 Quote Link to comment Share on other sites More sharing options...
pflaming Posted August 21, 2015 Report Share Posted August 21, 2015 (edited) We stayed night with the forum member who owns this car. It is his daily driver. He has a warning speeding ticked from Illinois for 84 mph. He is running a flathead. He sees no reason to change engines to get more speed! . Why is this upside down! Edited August 21, 2015 by pflaming Quote Link to comment Share on other sites More sharing options...
NiftyFifty Posted August 21, 2015 Report Share Posted August 21, 2015 Rolling down those Illinois mountains? LoL I've seen 75 on mine back before all my work...but it was the bottom of a good hill, and I think the cars had much better rear ratios, lighter, and more aerodynamic then the trucks....so your fighting against more then just the flathead in the trucks. I'm thinking my issues are now leaking valves or stuck rings...my compression test wasn't what I expected, but my new gauge is also something that looks like Mickey Mouse would use on Saturday morning.....so I'm not trusting it either. The more power is all based on your abilities and tools....no matter if you build the flathead or a swap in a V8, you gotta know what your doing, and be able to see it through or learn too. IMO building a flathead is a bit more challenging, especially come valve setting time and also waiting or seeking out parts. It's a pretty basic engine, but guys who know them well as wpgetting fewer and far between. Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted August 21, 2015 Report Share Posted August 21, 2015 Quote Link to comment Share on other sites More sharing options...
wayfarer Posted August 21, 2015 Report Share Posted August 21, 2015 We stayed night with the forum member who owns this car. It is his daily driver. He has a warning speeding ticked from Illinois for 84 mph. He is running a flathead. He sees no reason to change engines to get more speed! I must be getting old. I don't often go 84 in the wife's Navigator..... not sure that I like the old suspension design well enough to gamble... 1 Quote Link to comment Share on other sites More sharing options...
cavisco1 Posted August 21, 2015 Report Share Posted August 21, 2015 How about staying with an inline? An inline won't interfere with the steering. There is another poster on here with a 258 amc with 904 automatic. If the 258 fits then a jeep 4.0L should fit as well. I asked him how it fits and he said it didn't require cutting the firewall. Quote Link to comment Share on other sites More sharing options...
Jim Shepard Posted August 21, 2015 Report Share Posted August 21, 2015 I always thought a swap for a slant 6 would be interesting. If one could find a complete car then you'd have the entire drive train. An added feature is the availability of speed equipment. I think these are nice little engines... Quote Link to comment Share on other sites More sharing options...
NiftyFifty Posted August 21, 2015 Report Share Posted August 21, 2015 Amc or jeep still means all the pedal work, and the moving of the master cylinder, so with all that work, why not go full power of a V8? Depending on exhaust, the straight 6 might be worse then the V Quote Link to comment Share on other sites More sharing options...
cavisco1 Posted August 21, 2015 Report Share Posted August 21, 2015 http://p15-d24.com/topic/34746-trucks-with-modern-inline-engines/ Quote Link to comment Share on other sites More sharing options...
Jeff Balazs Posted August 22, 2015 Report Share Posted August 22, 2015 I wonder if it doesn't boil down to mainly a gearing or ratio thing with running these old flatheads. My 230 has plenty of torque........I just wish I had some different gear ratios to choose from. With my 3.55 rear axle and the fluid drive 4 speed first is still way too low to be of much use. Now if first was just slightly lower than the existing second......then second could be a shade higher ......same with third and then it seems to me that the optimum fourth would be a slight overdrive gear.....like .95 or maybe .92. These are just my seat of the pants observations so far. I do think the combination of the slightly later 230 I have and the fluid coupling makes this set up perhaps slightly more flexible in traffic than some other rigs. I don't know how one would go about creating this combination and still retain the fluid drive. I don't think it is possible or at least practical to do this with a T5. I really feel like the moment you swap the engine out of one of these trucks you might as well buy something newer. That old engine is the heart and soul of these trucks......and I just can't see them any other way. Jeff 1 Quote Link to comment Share on other sites More sharing options...
55 Fargo Posted August 23, 2015 Report Share Posted August 23, 2015 When I got my 52 1/2 ton it had no engine so I installed a Chrysler 251. It's ~2" longer than the original 218 so I shaved the head about .050, moved the radiator forward,installed 2" tabs on the front motor mounts to reach back to the mounting holes, and nipped a bit off the front cross member to clear the oil pan. I also installed a 66 T-Bird rear end w/3.0 ratio so I could keep up with traffic on the freeway. My truck has a 4 speed floor shifter from the factory with granny low and even with the 3.0 rear I don't ever need to use 1st gear. Old Yeller.jpg I always liked your "Yeller" truck Reg, did not realize it had a big block 251 in it. I also find my 251 with 3.23 rear gears still does not allow the use of granny 1st gear, except for maybe stump pulling. I have no troubles getting this truck up to 65 plus mph either/ How fast are you cruising with yours? There are a few on here that are convinced these trucks and flatheads in general are only good for 50 mph. The old solid axle front end, can be not bad if all is in good condition , king pins, tie rod ends, steering gear etc. I have a 318 LA engine, but have no immediate plan to swap her into the Fargo, might put it onto sons 1991 Fox Body Mustang......LOL and put a 283 SBC and powerglide into my truck, another..................LOL Quote Link to comment Share on other sites More sharing options...
Solution Joel Posted August 24, 2015 Author Solution Report Share Posted August 24, 2015 Thanks for all of the info I would like to stay Mopar but as a freshmen in high school I don't have the funds so I might go with the Chevy 350 but Ill have to wait and see what i can afford Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted August 24, 2015 Report Share Posted August 24, 2015 Thanks for all of the info I would like to stay Mopar but as a freshmen in high school I don't have the funds so I might go with the Chevy 350 but Ill have to wait and see what i can afford This may be a practical answer but in my opinion it is not the best answer. 1 Quote Link to comment Share on other sites More sharing options...
wayfarer Posted August 24, 2015 Report Share Posted August 24, 2015 Thanks for all of the info I would like to stay Mopar but as a freshmen in high school I don't have the funds so I might go with the Chevy 350 but Ill have to wait and see what i can afford For the life of me I cannot figure out how a shiverlay swap is less costly than an A-LA swap...someone please enlighten me. You really need to read through the various forums and see just how much work is involved in doing a v8 swap of any kind. If you expect to actually have a decent driver you will be spending plenty of money on all of the 'little' details that folks don't like to talk about. If all you're after is some kind of rat-rod that scares the rest of us on the road then perhaps the costs will be less... Know your limitations. 1 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.