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Twin Turbo Big Inch HEMI?

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:cool: Hey ya'll!

I am awaiting delivery of a new Mopar HEMI Mega Block- with the finished bore of 4. 5" and also has a raised cam option( for big inch clearance. )

I'm looking to do something wild with this little puppy for my 66 Charger- which has a Edelbrock Headed-Dual Quad- . 040" over 440 in it... .

Since there are people here on this website that deal with Turbos as a buisness I was wondering if I could get some information on installing turbos on it?
I am probally gonna go with a 5. 0" stroke crankshaft- with a 4. 5" bore it should yield about 636 cubic inchesOo. . So I am wondering which turbos would best suit this type of application?

Any type of useful info will be helpful if you are knowledgeable in this arena of engines... ... . ;)


Thanks in advance. :D



On Edit: This combination is destined to be purpose built for an attempt to run The Silver State Classic... ... ..... in the Unlimited Class... ... and ocassional Friday nite fun... . :-lafand YES! I am out of my mind!
 
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Mountain motor madness!!!! That's a drag racin engine right there Bill. Cool! I love them Hemi's..... Those new style pro stocker heads too? man! nice hardware... ... Different type of Hemi for racin but still VERY COOL nontheless!! Do ya got a Hemi in a Dart? 68? Got me a couple of old skool Hemi's and am awaiting the big thumper.....
 
RacinDuallie said:
:cool: Hey ya'll!



I am awaiting delivery of a new Mopar HEMI Mega Block- with the finished bore of 4. 5" and also has a raised cam option( for big inch clearance. )



I'm looking to do something wild with this little puppy for my 66 Charger- which has a Edelbrock Headed-Dual Quad- . 040" over 440 in it... .



Since there are people here on this website that deal with Turbos as a buisness I was wondering if I could get some information on installing turbos on it?

I am probally gonna go with a 5. 0" stroke crankshaft- with a 4. 5" bore it should yield about 636 cubic inchesOo. . So I am wondering which turbos would best suit this type of application?



Any type of useful info will be helpful if you are knowledgeable in this arena of engines... ... . ;)





Thanks in advance. :D







On Edit: This combination is destined to be purpose built for an attempt to run The Silver State Classic... ... ..... in the Unlimited Class... ... and ocassional Friday nite fun... . :-lafand YES! I am out of my mind!





RD:



Stick with a 4. 5" or 4. 625" stroke (572 or 588 CID). With the 5" stroke crank, your rod ratio gets way too short. Callies is the crank to get. mopar doesn't have one bigger than 4. 15-- way too short.



You want to run a hair shorter stroke to keep the angularity in check. You also want to run a little longer rod. Ditch the 440LY rods (6. 765") and go to a Hemi rod (6. 86") minimum, or better, the 7. 1" Eagle rods.



You'll want to run a custom piston to drop down to the BBC pin size (. 990).



The 572 or 588 is a much better street setup than a 605-636.



Cam should be a solid roller in the 255-265 duration @ . 050" range-- Normally a huge cam, but not with this displacement. It will idle smoothly.

Check out a Comp Cams XER series roller. Smooth idle and power to 7000 rpm.



Since your turbocharging, you need SERIOUS flow. Forget about a stock head, or even a Stage 6. You need an Indy head. Try the 440-1 with the full CNC port job. It's normally a little small, but this will help spoolup and bottom end torque.



Go with a low-profile indy intake, and King Demon RS carb.





With an engine like this, you could run an HY35-9 on each cylinder bank, and have a pretty good setup. Should clear a thousand hp, on pump gas.



Oh, and if you can afford it, a timing BELT is the way to go. otherwise, go chain. DO NOT USE A GEAR DRIVE.





jlh
 
Hohn said:
RD:

Stick with a 4. 5" or 4. 625" stroke (572 or 588 CID). With the 5" stroke crank, your rod ratio gets way too short. Callies is the crank to get. mopar doesn't have one bigger than 4. 15-- way too short.

You want to run a hair shorter stroke to keep the angularity in check. You also want to run a little longer rod. Ditch the 440LY rods (6. 765") and go to a Hemi rod (6. 86") minimum, or better, the 7. 1" Eagle rods.

You'll want to run a custom piston to drop down to the BBC pin size (. 990).

The 572 or 588 is a much better street setup than a 605-636.

Cam should be a solid roller in the 255-265 duration @ . 050" range-- Normally a huge cam, but not with this displacement. It will idle smoothly.
Check out a Comp Cams XER series roller. Smooth idle and power to 7000 rpm.

Since your turbocharging, you need SERIOUS flow. Forget about a stock head, or even a Stage 6. You need an Indy head. Try the 440-1 with the full CNC port job. It's normally a little small, but this will help spoolup and bottom end torque.

Go with a low-profile indy intake, and King Demon RS carb.


With an engine like this, you could run an HY35-9 on each cylinder bank, and have a pretty good setup. Should clear a thousand hp, on pump gas.

Oh, and if you can afford it, a timing BELT is the way to go. otherwise, go chain. DO NOT USE A GEAR DRIVE.


jlh

Justin,

The goal is to build a 600+ inch HEMI- not wedge!! You mentioned the LY rods- the 440-1 Indy heads and Stage 6 Mopar heads but they are wedge items and although they are all good performance parts for the Mopar Wedges- these won't even work on the Mega HEMI block..... Hemi's have an entirely Different pattern- piston design- port pattern layout ect. And the block again is the raised cam location block so running a t-chain is out of the question, the longer belt design from Jesel is required. The camshaft tunnel is raised . 250" higher up away from the crankshaft and standard length chains and belts or even gears for that matter will not even work on this type of block... . If you get the raised cam block this block is designed for the 600+ inches with the cam higher up out of the way- for utilizing longer strokes than 528-573-or even 588!! You don't get this block for that reason... this IS the block for those monster sized inches- not the Mountain motor that HemiDart posted that sweet pic of- that block has a wider bore spacing than this one...

I also think to run the HY's would be a joke here as well... ... the goal is flat out DISTANCE type racing not dragracin... ... You also mention a King Demon carb and that would be a blow thru type system but I'm talking injection... ... ... I do like Indy cylinder heads but I prefer the Indy legend series heads- I'm leaning towards the Indy Legend 426-1RA6 CNC ported heads- flow range is about 490- 500+ CFM @ 800" lift... ... and these heads are designed for 605- 636 cubic inches.....
 
Do you have a HP goal in mind? While I'd like to see a 600+ turbo engine's dyno sheet I'm wondering how you plan on hooking that power to the ground.



Al
 
metal tech said:
Do you have a HP goal in mind? While I'd like to see a 600+ turbo engine's dyno sheet I'm wondering how you plan on hooking that power to the ground.

Al

H. P. goal is gonna be BIG- but nowhere near the capacity of this blocks breaking point.....

Using a 5-Speed Manual Trans w- Gear Vendors and rear gearing in the 2. 64- 2. 86- maybe even 3. 23 gearing- not building a dragracer here but an engine that'll allow for top end racing capable of propelling me and my Charger to speeds in excess of 200 plus m. p. h. on the closed course racing event- The Silver State Classic or even Speedweek @ Bonneville Salt Flats. So mad rev gain off the line is not a primary concern- but gradual rev gain to get into the upper digits of the speedometer safely without harming engine or drivetrain... not a drag racing type rev gains- still fast- but not quater mile type rev gains... . Aluminum rods are out of the question. Engine needs to be durable for lengthy running @ speed.
 
RacinDuallie said:
Justin,



The goal is to build a 600+ inch HEMI- not wedge!! You mentioned the LY rods- the 440-1 Indy heads and Stage 6 Mopar heads but they are wedge items and although they are all good performance parts for the Mopar Wedges- these won't even work on the Mega HEMI block..... Hemi's have an entirely Different pattern- piston design- port pattern layout ect. And the block again is the raised cam location block so running a t-chain is out of the question, the longer belt design from Jesel is required. The camshaft tunnel is raised . 250" higher up away from the crankshaft and standard length chains and belts or even gears for that matter will not even work on this type of block... . If you get the raised cam block this block is designed for the 600+ inches with the cam higher up out of the way- for utilizing longer strokes than 528-573-or even 588!! You don't get this block for that reason... this IS the block for those monster sized inches- not the Mountain motor that HemiDart posted that sweet pic of- that block has a wider bore spacing than this one...



I also think to run the HY's would be a joke here as well... ... the goal is flat out DISTANCE type racing not dragracin... ... You also mention a King Demon carb and that would be a blow thru type system but I'm talking injection... ... ... I do like Indy cylinder heads but I prefer the Indy legend series heads- I'm leaning towards the Indy Legend 426-1RA6 CNC ported heads- flow range is about 490- 500+ CFM @ 800" lift... ... and these heads are designed for 605- 636 cubic inches.....





OY VEY!! *HEMI*! How did I miss that part?



The Legend head you mentioned is PERFECT for your application. The raised angle helps flow a bunch.



While the raised cam helps stroke clearance and will let a 5" Callies swing just fine, you STILL will run out of deck height. RB Mopars have a 10. 72" deck height. Standard Hemi rods are 6. 86". Now, that means that the compression height you can run is down to 1. 36" Keep in mind that the stock piston has a compression height over 2"! Now, 1. 36 is doable for an engine where it doesn't matter if the rings last very long. But you mentioned ENDURANCE racing. I assume that you want the engine to not have blowby after 5K miles?



Not only are the pistons too short-- so are the rods. Your rod ratio with a 5" crank drops from the stock Hemi value of 1. 83 down to 1. 372-- UNACCEPTABLY LOW. Heck, even down to 1. 45 or so (stock 400 Small block Chevy) is unacceptable.



The only way to get your rod ratio up is to run a longer rod OR a shorter stroke crank. The only longer rod available to my knowledge (that's not a custom piece) is the 7. 1" Eagle Rod. I think Manley also has a 7 incher. So, with a 7" rod and your 5" stroke, you've only managed to increase rod ratio to 1. 4-- STILL too low. AND to run this longer rod, you've had to FURTHER shorten your pistons down to a 1. 12 compression height!! GOODBYE PISTON RINGS!



Now, you can get away with a shorter piston IF you have a longer rod and higher rod ratio. IF you have long stroke with a relatively short rod, then you MUST have a taller piston to handle the extreme side-loading on the bores.



Ever notice how tall a CTD piston is for the 4. 72" stroke???





So, the long and short of my opinion is that you wasted money on a raised cam block. A standard cam bore block will accomodate the stroke length you SHOULD be running (4. 625" max).



The raised cam blocks are for mega-cube engines that only have to run 5 minutes at a time-- NOT something that will run coast to coast.



A 4. 625 stroke crank (and 588 CID value) lets you run a 7. 1" rod with the following results: piston compression height is 1. 3" (short, but doable only because you have a better rod ratio), and a rod ratio of 1. 53, which is low, but acceptable. It's the same rod ratio a small block mopar Stroker would have with the new 4" crank.



Going for the last 40-50 cubic inches on a turbo engine is not wise, imo. That's why you have TURBOS-- so you don't need the last few CID.



Far better, imo, to build a strong engine operating under less stress and raise the boost than to build an engine with poor geometry and have to run limited RPM and limited boost.



Besides, doing it this way costs less because you don't need so many custom pieces!



We don't need no stinking raised cam block:)







JMO



Justin
 
Oh-- and you're going to want to enhance durability in other ways too.



I'd install piston oil squirters like the CTDs have. I forgot who makes them, but all you have to do is drill and tap the galleys from the bottom and screw them in. They are brass.



Also, consider Evans NPG+ coolant. Should help with detonation, too.



For airflow, you may have a hard time finding big enough injectors. Try the Turbo Buick guys for injectors. For this much HP, you'll probably need something 80lb/hr injectors or bigger.



For turbos, maybe dual Dodgezillas would be enough air? Or maybe dual full PDR 40s?



Keep in mind this kind of engine will move more air at 10psi of boost than a CTD5. 9 will at 40psi. (because of the heads).



JMO



I'm sure someone can explain why I'm wrong.





Justin
 
While you have added this thought to the 636's rod ratio and its true nature for this size engine is indeed drag racing, I may just have to downsize the cubic inches slightly... .

I plan on running one of them oil accumulator tanks on it as well as having Thermal Barrier Coatings and friction reducing coatings -just in case... .

I really don't think that the diesel engine type turbos would survive the rpm's that you get with Hemi engines? I could be wrong in some other type gas engine builds maybe they would work- but I don't think their presence on this type of engine would be of any benifit..... has to have top shelf bearings and ample supply of cooled oil flow... . gonna have to be creative on keeping ALL the fluids cool to prevent a breakdown- coolers galore... .

This will be an interesting package to put together as wellas planning the recipe... ...

And I didn't pay for this block it was a trade up- I traded a Mega Block Wedge un-cut for this raised cam Mega Block Hemi that's finish bored, and sonic tested already... . I'd rather build up a Hemi than the Wedge for the superior airflow of the heads in comparision alone..... Have you tried to get a Mega block Hemi from the vendors or direct lately? Good Luck!! But they do have a limited supply of the raised cam blocks and I grabbed what I could... ... .
 
Fair enough.



I'd have kept the Wedge block and done a Stage V conversion :D



#ad




They move a LOT of air, and fit on the Wedge block.





If you want SERIOUS power, you should look at the Indy Maxx block. Somehow, the idea of a 605" Hemi that weighs less than a small block appeals to me :confused:





Justin
 
Yes I've known about the Stage V 'Wedge to Hemi conversion' for some time now and was even thinking of trying that route- exactly before this trade talk thing was going on- I do have the Mopar Stage 6's too(Wedge Head) with the angled plug location and Max Wedge ports- they get to sit for future useage. But for now I have to plan a build for this block I have coming- Raised Cam Hemi Mega Block... ... . Even mildly built this thing should haul butt... ... ...
 
I see that your learning quite a bit on that "other" forum I mentioned. Now don't be greedy, share some of what you've learned. Some of us have projects that would benefit from the sources your getting refered to.



Al
 
MT-- who are you referring to. And to whom are you speaking?



Most of the Mopar stuff I know I learned a long time ago-- regrettably, I'm not current to the extent I'd like to. Kinda gave up on gassers, so I'm sponging up diesel stuff.



jlh
 
I was asking RacinDuallie to share some of what he learned from the people he was referred to over on Turbomustangs forum. I'd like to hear what the viper guy had to say about his plans. As this has more in common with my future project than any turbo drag car setup.



Al
 
Go with twin T-88's and you will be virtually unlimited in the horsepower department. Go with a single 106mm and you will be limited to about 2500hp. Either way you will easily blow past 200mph, but will the car handle it? I'd FAST inject it, put it on alcohol, and run the twin 88's, that way you don't have to intercool it...
 
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