flathead mods

[vitamindart]

ok i've been kicking around keepin the flathead,hotroding it up i realilize its never going to be a rocket ship but i dont want it to be a snail..

i see there are a couple different people selling adapters to a t5 has anyone else done this ??how did it go , how did you do it ??? what gearing did you run in the rear axle ???

has anyone turbocharged a 218???

many this is one heck of a mess i've gottin myself into i've got alot of work to do

i just think the flathead will be alot cooler than the cookie cutter small block chebbie street rod

[Norm's Coupe]

Don Coatney used a T5 in his P15. However, he also changed the engine to the larger DeSoto engine. He had his adapter made locally by a machine shop. You might try sending him a private message for details.

Other than that you may be able to buy or have an adapter made by Wilcap. Check the Street Rod and Custom Rod magazines for their address. Or, run a google search, they do have a website.

That said, you can do all the engine hopping and tranny swapping up you want. Doing so probably won't give you that much more speed though. In order to get the speed to go along with the hopped up engine and the tranny, you'll also have to change the rearend. That rearend will still keep the car from getting up a lot of speed. Don Coatney also used a more modern rearend in his P15.

[greg g]

Remember you are dealing with a low compression, long stroke motor. They produce a lot of torque. Most of the folks who have driven them will tell you they will pull in 3rd gear from 15 mph on up, and from 40 to 60 are probably just as quick as some modern cars. Also keep in mind that the roads when they were built allowed and average speed of probably 45 mph, with lots of stop and go, as such they were geared accordingly.

So with this in mind, the best set up for current conditions is more compression,( a combination of up to .070 from the head and block will still run on regular) better breathing, dual exhaust or a low restriction system seem to be very beneficial. Gearing the rear end for todays highway speeds while allowing the the engine to be on its torque curve is also a good idea. 3.23 or 3.55 seems to be good consensous ratios.

[eric wissing]

Grahams in the late 30's used a super charger on their sixes. How effective would this be? Even a small boost would help and would not mean much alteration. (I think)Probably has been brought up before. So to think about. Any ideas out there? Eric

[Guest 50Plymouth]

Grahams in the late 30's used a super charger on their sixes. How effective would this be? Even a small boost would help and would not mean much alteration. (I think)Probably has been brought up before. So to think about. Any ideas out there? Eric

Graham's I think had 217.8 i6's (so again, 3.6L like our beloved cars). Without the supercharger I believe the hp rating was 94. With supercharger 124. Not a bad % jump considering the era.

oh, here's a link with a tiny bit of info:

http://www.conceptcarz.com/vehicle/z12064/Graham_Hollywood%20Custom%20Supercharged/default.aspx

Ryan

[Guest rockabillybassman]

Seems to me a change to a 230 motor with it's stock 117hp would be a good place to start. I've ridden in a 218 powered car with twin 97's, and my stock 230 seems to go better.

[teardrop puller]

I am using a Chevrolet 700R4 automatic behind my stock block P18l

I have only driven it a few times and it has plenty of power. Here is what I have on the engine. Langdon's duel carbs, cast iron headers and electronic ignition. The rear end is a Dana 44 out of a Mexican Dodge with a 3.2 ratio. I hooked the teardrop on to see how it pulled and how much power it had, I was impressed with the performance.

Kai

[blueskies]

i just think the flathead will be alot cooler than the cookie cutter small block chebbie street rod

I couldn't agree more!

Everything I've done with mine can be seen here. A stock overdrive is a bolt in swap, no other mod's necessary, if you don't want to take on the T-5 swap. Makes a world of difference in driveability, I can't imagine my car without the OD.

Pete

[bob westphal]

There are quite a few of those on this forum that have modified the flatheads. I'm currently running a Offy intake with stock carbs and split exhaust. This mainly for nostalga. You're correct in stating that they won't be a rocket. However, these engines can be made to run with some of the average modern cars. Many years ago I built my 218 to run the 1/4 mile in the mid 80s in the 15 second bracket. I used the stock rearend and tranny unlike some of those on the forum. I found the best improvement in acceleration was a light flywheel/clutch assembly. I used a Edmunds intake with two 97s, Edmunds head milled to 10.1. Isky 3/4 cam and .060 over bore, home made header into a collector box. I blew off a lot of the SBC and Fords.

The turbo or blower would work very well with the long stroke torque these engines produce and would be way out of the normal stuff you see under the hoods of modern hotrods. Do it!

Bob

[Lou Earle]

I have a overdrive from George Asche behind a stock 218 and am very satisfied. I cruise at 70-75 on interstate and get 20-22 mpg all day long.

I believe the key is the rear end ration Mine is 3.9 and that is just great for around town acceleration and then with 30 to 33 percent reduction your driving with about a 2.50-2.75 in overdrive. Best money I have ever spent on one car.

I will be putting a hotrod 230 (Built by Asche) in my taxi and that overdrive.

Bet it will haul A then!!! That has , I believer a 4.1 rear. If that is 2 fast a rear I have a set of to put in. Remember the overdrive set up usually an 4.11 rear I am told.

For my money the best increase in power comes from exhaust splitting somehow. Everything I have read and my personnel experience sustains the literature- it gives about a 102 to 12 % increase in hp and the dual carbs about 7%. Milling the head gets a bit more but unless u go a new cam the best best it just split the exhaust in the beginning.

The reality is this-to me

About 1500 for the overdrive- and a NO NONSENSE COMPLETE BOLT IN. And you Can cruise at 65-75 without the motor screaming all day. Any add ons to the engine are pure additional pleasure.

[Brendan D25]

Did somebody here install a Granada rear end in a P15 a couple of years ago? The bolt pattern would be the same, and I think they are pretty close in width. I have one, but have not had a chance to look at it for ratio or width. It came from a Granada with a six cyl. automatic.

[greg g]

You can also upgrade to Lincoln Versailles rear disc brakes on those rearends.

[vitamindart]

i was kind of figureing on the 3.23 or 3.55 rear gear as its seems to be the popular choice from what i've read about your cars . i also was looking int going to the larger 230 ,a aluminum head as it must way a lot less (and looks way cooler) electronic ign is a must (never cared for points) i'm hoping to get it to look like a rod from the fifties (wide whites ,steel wheels ect) i guess i was born about 50 yrs to late as i don't care for the modern cars so much

does anyone know if you can swap spindles from side to side , i was kind of thinking of running a rack & pinion but would like to mount it in front of the cross member

thanks again for all the help

Dominic

[John Burke]

Dominic...here is a picture of my Desoto powered hot rod...It's a 251 ci motor with a milled head and a dual intake by Edmunds...I just finished putting on Holly 94's tonite. I am running a 350 turbo automatic using an adaptor from Wilcap... I am using an 8" ford rear end from a 63 fairlane. I had 3.00 gears but am upping that with a 3.40 pumkin for a bit more bite off the line. I really don't give a hoot what the gas milage is...John

[jd52cranbrook]

Dominic...here is a picture of my Desoto powered hot rod...It's a 251 ci motor with a milled head and a dual intake by Edmunds...I just finished putting on Holly 94's tonite. I am running a 350 turbo automatic using an adaptor from Wilcap... I am using an 8" ford rear end from a 63 fairlane. I had 3.00 gears but am upping that with a 3.40 pumkin for a bit more bite off the line. I really don't give a hoot what the gas milage is...John

Awesome car:cool:

[Olddaddy]

My personal opinion is that balancing these engines is the best money you can spend for the return in power and rpms. I am building a 218 using 230 crank and rods. Bore will be whatever is needed to clean up the cylinders. Mill head and deck block to a combined .60-70K. I will run a 2bbl carb on a modified original intake. Dual exhausts via a second dump added to stock exhaust manifold. 12V neg ground Mopar electronic ignition. I'm running a Mopar 727 short tailshaft automatic with an 8 3/4 rear end, 3:23 ratio. I currently run 70 mph with ease, but pulling the 3:23 off from a dead stop with a stock 3 speed requires clutch slipping. My car is not a P15, but a 50 model Suburban, maybe a bit lighter, but entirely similar mechanically. I also have aluminum radiator, alternator, four wheel discs, relocated shock mounts, firewall mounted mc. Build the flathead, ohv are a passing fad. And always remember, free advice is worth exactly what you paid for it.

[vitamindart]

olddaddy how did you adapt your 727 is it a sb ,bb or slant 727 what do you mean about the clutch slipping and balancing is a must with any rebuild as far as i'm concerned

[Olddaddy]

I am using a Mopar adapter from an airline tug. These were made in the early 60s and can be found in equipment salvage yards. I believe the tranny is a big block 727, but would have to confirm it to be sure. It uses an eight hole flex plate from a hemi, and an eight hole crank adapter, plus the adapter plate.

You have to "slip" the clutch to get the car to start roller, build rpm and let it out all the way once you're moving.

[Don Coatney]

ok i've been kicking around keepin the flathead,hotroding it up i realilize its never going to be a rocket ship but i dont want it to be a snail..

i see there are a couple different people selling adapters to a t5 has anyone else done this ??how did it go , how did you do it ??? what gearing did you run in the rear axle ???

has anyone turbocharged a 218???

many this is one heck of a mess i've gottin myself into i've got alot of work to do

i just think the flathead will be alot cooler than the cookie cutter small block chebbie street rod

Follow this link for information on how I did my T-5.

http://www.jalopyjournal.com/forum/showthread.php?t=74221&highlight=t-5+coatney

[Merle Coggins]

I am using a Mopar adapter from an airline tug. These were made in the early 60s and can be found in equipment salvage yards. I believe the tranny is a big block 727, but would have to confirm it to be sure. It uses an eight hole flex plate from a hemi, and an eight hole crank adapter, plus the adapter plate.

You have to "slip" the clutch to get the car to start roller, build rpm and let it out all the way once you're moving.

I'm still confussed. Why would you need to slip the clutch if you're running an auto trans? I understood the term, but wondered why that would be an issue with the 727.

Merle

[Plymouthy Adams]

Charlie is just now installing the automatic and is not back on the road yet..the slipping is in reference to the before automatic when he installed the 3.23 gears and running with the clutch..

[tragic59]

I'm still confussed. Why would you need to slip the clutch if you're running an auto trans? I understood the term, but wondered why that would be an issue with the 727.

Merle

He was referring to slipping the clutch when he still had his 3 speed manual.

[Merle Coggins]

I get it now. I guess I missed that little tidbit of information before.

[rearview]

don't worry Merle, it wasn't just you. I was scratching my head also. Some of the roundy round guys here set up the automatics to run like that, but I was wondering why on a streetcar.

Back on the short bus....

[Plymouthy Adams]

I admit that I was a bit more in the know, Charlie and I have discussed this a few time on the phone..I am anxious to see his 'burb when finished. To expedite his car being back on the road, he is not doing all he wanted to do this time around.