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Does it have a Hemi!?

ask away, there isnt much I dont know about the chrysler hemi nowdays.

l_e0a3b6c23ff94698be1a302523fec6f3.jpg


to clear up a few misnomers:
1. you can get the weight of a hemi down to about a BBC. It takes some money and allot of cast aluminum.
2. it is cheaper to build a SBC then a hemi....but then your stuck with a SBC. It really isnt that bad. Pistons can be had for pretty cheap unless you want that custom set like I had made. I would say its about 1 1/2 times more expensive.
3. Chryslers are better to build because there are many more parts and speed parts out there. A desoto has nearly no speed parts and the ones that do pop up cost more then most motors with the dodge being only slightly better.
4. 392s are acutally cheaper then a 331 or 354 because of the part on the market. But if you know allot or read allot you will learn that you can mod a chevy distributor to fit, chevy water pumps will save 40 pounds, use small block dodge starters etc.
4. Bob Walker is one of the most knowledgable and will answer any question you have. He is super busy but if they can get him to the phone he can answer any question you would have. Also Pat at Wilcap has the whole tranny adapter thing down to simple packages.
5. I have a copy of an article by Gene Adams somewhere. The hot setup according to him and my dad (who built funny car motors through the 70s) is a 392 block with 1955 331ci heads. These are the best heads having the best volumetric efficency and flow plus a little higher compression. Plus the bore and stroke of the 392.

mine is a 1955 Chrysler 331 with the good heads punched to 346 with tons of head work.

kisses,
Chop
 
chop said:
ask away, there isnt much I dont know about the chrysler hemi nowdays.

l_e0a3b6c23ff94698be1a302523fec6f3.jpg


to clear up a few misnomers:
1. you can get the weight of a hemi down to about a BBC. It takes some money and allot of cast aluminum.
2. it is cheaper to build a SBC then a hemi....but then your stuck with a SBC. It really isnt that bad. Pistons can be had for pretty cheap unless you want that custom set like I had made. I would say its about 1 1/2 times more expensive.
3. Chryslers are better to build because there are many more parts and speed parts out there. A desoto has nearly no speed parts and the ones that do pop up cost more then most motors with the dodge being only slightly better.
4. 392s are acutally cheaper then a 331 or 354 because of the part on the market. But if you know allot or read allot you will learn that you can mod a chevy distributor to fit, chevy water pumps will save 40 pounds, use small block dodge starters etc.
4. Bob Walker is one of the most knowledgable and will answer any question you have. He is super busy but if they can get him to the phone he can answer any question you would have. Also Pat at Wilcap has the whole tranny adapter thing down to simple packages.
5. I have a copy of an article by Gene Adams somewhere. The hot setup according to him and my dad (who built funny car motors through the 70s) is a 392 block with 1955 331ci heads. These are the best heads having the best volumetric efficency and flow plus a little higher compression. Plus the bore and stroke of the 392.

mine is a 1955 Chrysler 331 with the good heads punched to 346 with tons of head work.

kisses,
Chop

Thanks Chop! It seems the more I learn about this, the more questions I have.

Thanks for the offer!

David
 
OK, I've been reading and reading and reading. I don't even have the books I ordered yet, but the web is an amazing place for information! :cool:

I have learned that it's very possible to get into an early 1G Hemi without selling a kidney. I even stumbled across a completely rebuilt 392 for about $2,500, right here in Denver. If I hadn't been so unemployed for so many month's now, and so conservative with my money, I would have jumped on it. But at least it shows me the deals are there. ;) Yay!!!

I'm setting my budget for my future Hemi at 3 to 4 grand. I think I can do well in that price range. I know that seems like a lot compared to a small block, but I would really like to run one of these if I can. Now I just need to get some steady work so I feel safer about dipping into savings (DAMN ECONOMY:mad:). I am finally starting to get some work now (picture tubby bald guy looking up to the sky and crossing fingers :neutral:).

I've also decided to go with the larger Chrysler Hemi. It weighs more than, and is physically larger than a big block chevy, makes half the power for twice the price to build, and probably gets horrible mileage. But hey, it's a Hemi! :lol:

The truth is, the larger Chrysler Hemi is much cheaper to build than the smaller Dodge and Desoto Hemi's, and parts are easier to get. I really wanted to go with one of the Dodge RedRams (baby Hemi's) for the size issue, but they are the most expensive to rebuild. I'm considering making my body a few inches wider to help deal with the possible funny look of this engine being so wide. I'm still not sure how that would work. At least the 26/27 body style I'm going for has the wider firewall than the bucket. It does, doesn't it?

Just for comparison, a couple weeks ago, I saw a running 350 chevy with turbo 350 trans here in Fort Collins Craig's List for 400 bucks. The add said that you could drive the truck before the engine was removed. I can't vouch for what shape it's in, but to me that seems cheap. :eek:

Thanks everyone for the input so far. If anyone has anything else to say, please speak up! I'm still just learning about this great older engine. :)

Take care,

David
 
RexRod said:
It weighs more than, and is physically larger than a big block chevy, makes half the power for twice the price to build, and probably gets horrible mileage. But hey, it's a Hemi!


your half right...They are larger but dont have to weigh more. Dump the cast water pump, water crossover and intake. Replace them with some aluminum and your just a bit under the weight of a big block.

Half the horsepower for twice the price???? Seriously...maybe someone else should spec the parts and build your motor.

My rebuild cost including machine work was right at 2.5 grand. Half of that was a set of pistons that I had custom made because I couldnt find ones in the spec that I wanted. So I had Ross make me a set of forged aluminum with a bigger compression ratio, venting and some other things I wanted to play with. I had tons of machine work done. We had to chamfer the top of each cylinder .25 just to be sure the valves would clear. My 331 is now a 346 +/- 2 c.i. and pushes somwhere around 430 hp at 11.5:1 compression. Also, with the machine work, not only is the motor a torque monster but I can stretch its legs and wind her up pretty high (for a hemi). With the weight of the car, money factored in, and the ability of the motor to run a two speed and still leave everything at the light I would say that it is a very viable motor to work with.

plus, it isnt a chevy.
 
chop said:
your half right...They are larger but dont have to weigh more. Dump the cast water pump, water crossover and intake. Replace them with some aluminum and your just a bit under the weight of a big block.

Half the horsepower for twice the price???? Seriously...maybe someone else should spec the parts and build your motor.

My rebuild cost including machine work was right at 2.5 grand. Half of that was a set of pistons that I had custom made because I couldnt find ones in the spec that I wanted. So I had Ross make me a set of forged aluminum with a bigger compression ratio, venting and some other things I wanted to play with. I had tons of machine work done. We had to chamfer the top of each cylinder .25 just to be sure the valves would clear. My 331 is now a 346 +/- 2 c.i. and pushes somwhere around 430 hp at 11.5:1 compression. Also, with the machine work, not only is the motor a torque monster but I can stretch its legs and wind her up pretty high (for a hemi). With the weight of the car, money factored in, and the ability of the motor to run a two speed and still leave everything at the light I would say that it is a very viable motor to work with.

plus, it isnt a chevy.

Well, I stand corrected. What I know so far is only what I've been able to find on the web. According to you, it sounds like it's going to be better than I thought! That's gota be good. :cool:

I'm sorry if I sounded a little to authoritative. ;)

David
 
no prob, I had all these questions when I got my first hemi. I was scared to death that it would cost me an arm and a leg, wouldnt run as fast as the stroker motor I had at the time and I didnt know anything about them internally. I found out that they are just another motor, inside of them holds no black magic or witchcraft, and assembly was pretty easy. There are some minor differences between these and a small block chevy but not enough to worry about. Parts are a little more expensive but machine work is machine work no matter what motor it is.

The one thing about a hemi is they need compression. They move air great and have the ability to push a ton but that 9:1 is for a passenger car. For a driver go at least 10:1 unless you want a real hotrod then bump to 11 or 11.5:1.
or run a blower.

you also cant spin them like I could my 327. I could shift it a 7200 rpm but I wont take the hemi over 5500. So build the motor for low end power since it wont spool up as far.
 
chop said:
no prob, I had all these questions when I got my first hemi. I was scared to death that it would cost me an arm and a leg, wouldnt run as fast as the stroker motor I had at the time and I didnt know anything about them internally. I found out that they are just another motor, inside of them holds no black magic or witchcraft, and assembly was pretty easy. There are some minor differences between these and a small block chevy but not enough to worry about. Parts are a little more expensive but machine work is machine work no matter what motor it is.

The one thing about a hemi is they need compression. They move air great and have the ability to push a ton but that 9:1 is for a passenger car. For a driver go at least 10:1 unless you want a real hotrod then bump to 11 or 11.5:1.
or run a blower.

you also cant spin them like I could my 327. I could shift it a 7200 rpm but I wont take the hemi over 5500. So build the motor for low end power since it wont spool up as far.

I really appreciate you comments Chop, more than you know. Now, I'm not an engine designer, or builder. But after saying that, I have spent some time tuning them, but only with computer control of some kind. So I have some questions:

You talk about 11 or 11.5 to 1 compression for a street motor. Does the Hemi chamber allow for this kind of compression on pump gas without detonation problems? Or are you using some kind of engine management system like MegaSquirt?

I ask because I'm not used to hearing about street motors that run on pump gas with compressions that high without some kind of help from a computer, at least controlling spark advance and/or profile. Now, I've seen street motors built up to as high as 14 to 1 compression that ONLY run on E85. E85 can have octane ratings between 105 to 110. Some say it can be as low as 100. The motors also typically benefit from the natural cooling properties of the ethanol as well.

David
 
I only had issues with motors built above 12:1. Even then the detonation issue wasnt really noticeable. I was running a 6AL box with an MSD distributor. It got really bad when I did a big block at around 12.7:1. I started to have to mix AV fuel with hi test. These were all chevy small and big blocks. The hemi design for street use wont handle that much compression well. Most piston mfgs that know anything will try to stay away from that unless its a full race app. My dad has an outstanding 354 that runs smooth as glass at 10:1. If you arent building a car to be a street fighter then that is about the perfect compression. maybe up to 10.5. remember that a bucket is really light so if you have a rough idle you can really feel it.
I built mine to be a stop light to stop light car. It dosent detonate at all and I run alot of advance and really rich. My theroy is that they flow so well, the cylinders are less c.i. and the intake and exhaust ports are really large. So it is able to push the mixture through the combustion chamber very quickly. It may have something to do with the larger intake and exhaust valves as well. But with the large cam and more compression it is impossible to smooth the motor out. My bucket shakes sitting at a light but I am young and dumb enough that it doesnt really bother me.
 
OK, a word here. Chop, you live in Denver. You may be suffering from Elevation. The higher you live the more compression you can live with. 10 to one is HIGH compression in most places and will detonate if things are not very close to perfect. Even down here at El Paso (4000 ft). At sea level you better have the combo spot on or unleaded premium will kill you. Most of our hot rods are not blessed with knock sensers that retard the timing automatically for us. T's are low load, and with hot cams we can push the issue, but why?
:lol:
 
why? simple, for the sake of going fast. I cant afford a blower setup so I build the motor to run as powerful as possible.

In denver finding 12:1 and 12:5 cars isnt hard. Quite a few muscle cars and hot rods run a high compression setup.

when people ask me questions I assume its about hotrods, thats all I know. If you want high mileage motors that travel across the country or want it to pull a 5000lb cadillac around then I'm not your guy. I dont do street rods, touring cars or customs.

A hot rod is about going fast. You take the biggest motor you can build and put it in the smallest and lightest car you can find then rip off everything that doesnt fall into the function catagory.
 
I'm building mine with a '57 Desoto 330 ci hemi and an A-518 automatic. The whole combo weighs in excess of 900 lbs.
 

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