HEMI Build: Initial Mockup Pictures

At long last - picked up the majority of the engine components from the machine shop . . . after almost 2 years of work. Why did it take so long . . . because I'm doing things that aren't "normal" for street engines - just takes a long time.

This engine is pretty much setup as a late 60's top-fuel motor. I found the Donovan 417 heads from a AAFD car -- decided to adapt them to run on a 392 block on the street. I'm not sure if anybody has actually done this before - guess we'll see how well they work out.

I'm "shoe horning" the engine into my 34 five window -- with a 60's style build. Given the heads, blower, etc -- that is the period it fits the best.


Here are the engine specs:

1) 1957 392 Hemi Block - "A1" Casting

- Hot tanked and acid dipped to remove rust & scale
- Bored .030 over
- 4-bolt ProGram main caps on the center three
- Align bored and honed
- Block was ground smooth on the outside ( cause I like cast iron in my nose )

2) Crank and Rods

- Forged 392 Hemi crank
- Flywheel flange drilled for 1/2" NF bolts and setup for manual trans
- Oliver 426 Hemi billet rods - 6.86 length, 1.031 pins. They have been narrowed for 392 bearings
- Crank: .010 on rods/mains

3) Heads & Rockers:

- Donovan 417 Hemi alumiinum fuel heads
- Originally dry decks - water only on the exhausts. Drilled water passages on the lower side and added a water source from back of the block to the back of the head for high-flow. (You can see them in one of the pictures)
- Rocker Arms: Custom made by Rocker Arm Specialists . . . an ordeal in itself.
- Valve covers: Donovan 417 - almost unobtanium . . . but do fit the head profile and clear the springs/rockers.
- These heads were really designed for top-fuel - they have massive ports and require a special blower manifold (lucky to find) and custom exhaust flanges (making the headers will be more fun!).

4) Cam & Timing:

- Special order from Bullet Cams
- .550 net lift and 248 duration at .050
- Milidon gear drive.
- May switch over to a roller - depends how this thing runs and sounds

5) Blower:

- Vintage 6-71, rebuilt by Fowler Racing Engines
- RCD crank hub, belt and drive

6) Fuel System

- Initially dual BG 650 blower carbs
- Will update to Hilborn 4-port injection ( will convert from mechanical to EFI )

7) Ignition

- Offset 426 distributor -- MSD trigger ( no advance )
- MSD 7535 digital 7, boost retard

==================================================

If anybody is headed down the blown early Hemi path - will be happy to share what I know, parts suppliers, etc.. The more I can help others, the better.

Here are initial mockup pictures ( will be torn down for painting, pan fitting, etc):








Here you can see where we created some special thermostat housings to go on the front of the head -- kind of like a Flathead Ford. (Showing my flathead roots). I hate those damn Red/Blue fittings and stainless braided hose cross-overs that everybody puts on 392's -- seems like "Hooters Orange Shorts" . . . were fine 30 years ago . . .



Here you can see the 90 degree water inlets on the backs of the heads -- the back of each block deck has a 5/8" NPT hole (to plumb water back into the head for the round trip ). I believe that enough water can be routed back through the head to cool it. (Have a high-flow BBC style pump on the front).

 

In the words on Lewis Black....

HOOLLLLYYYYYYY FUCKIN MOSES! dude that thing is sooo sick. and it's not even in a damn car yet! :drool:

What kind of power are you hoping for?

 

Drooooooool!!!

 

Thats is going to be a nasty street motor, I feel bad for who ever crosses paths with you. Maybe the blower will indicate it's seriousness....

 

wow.....that is mechanical porn.... that is going to be one cranky elephant... wish my 331 is 1/10th as cool...

Congrats, great to see your dream coming to reality.

Cheers,

Drewfus

 

Thanks HAMBers . . . all I can say is that all good things take time and patience. I have a long way to go, but getting the engine components back is one hell of a motivation and inspiration. There is nothing like starting a brand new blown motor . . . nothing in the hotrod field matches this for me -- except maybe when you take a rod for its maiden voyage.

I'll keep posting the technical specifics of how we setup things --> the rocker arm oiling system, the water system, etc. I'm going to build a test stand for the initial fire, then take it to a dyno for testing and initial tune.

 

if there was one thing i wish i knew more (a lot more) about, it would have to be motors. I would love to build one some day.

 

Gorgeous setup. Always loved when people grind down the block to smooth it out. Amazing job on it all.

 

Now B&S....I KNOW you're a Flathead guy (like me) but aHemi is a Hemi.....right LOL !!

I will be following you down the same path with a Firedome - however ill deviate a bit with the carbs and a slightly more trad looking setup.

Can Bullet Cams knock up a cusotm cam for a Desoto Hemi and if so, do you have their contact details?

Great stuff...keep us posted with the pix champ and I applaud your patience and determination!!

Rat

 

I can see where you're going with the trad setup . . . I pondered it for awhile and decided that what I really was doing was late 60's top-fuel. There is no way those heads will "work" in a 50's style car -- and even blowers were pretty rare. I bought the BG Demon carbs because I know they'll work great and get me started. I also bought a six 97 blower manifold from Aaron at Savage . . . will try that as well ( I have lots of 97's to play with ).

I've sent a couple eMails to Rodder's Journal to see if they were interested in a build like this -- with some real dyno testing of different induction systems --> like 6-97's, 6 of the new BG Demon 98's, dual fours, Hilborn 4-port EFI, etc.. Sent them two eMails -- have heard nothing back . I think it would be cool to do a real article on a build and then dyno pulls . . . instead of the "scratch the surface" articles we see in the rags/mags. You'd think they'd at least be interested enough to chat about it.

Enough of my rant . . . time to chill a bit!

 

I got MAJOR WOOD!

Sorry for the visual...but that flatout ROCKS!

 

Somehow I don't think that 6-97's could keep up with that thing at flight revs... will be interesting to watch the variations between arrangements...record all the info, look forward to reading.

On a tangent, what sort of PSI are you aiming for with the blower?

that's going to make that 5 window live life like it never thought it could.... yee-haa.

Cheers,

Drewfus

 

I'm planning a blown 331 Hemi for my '31 coupe, so I can't wait to see how your 392 works out. Looks great so far!!!

 

I had my annodized fitting sandblasted.

There are two trains of thought: cheap, and not cheap.

There are two kinds of hot rodders: see above

Great looking engine!! No shit, that thing is over the top!

 

Stuff the mags , keep the punters guessing .........as my old man used to say .. thats a beautiful sight for sore eyes......Steve in Oz

 

That is one fine build on the 392. I love the heads and rocker assemblies. I hope you got the oil passages lined up on the rocker assemblies because if they are off you won't get oil up top. Did you modify the rockers for more oil from the standard setup? How are you going to tie the coolant outlets together?

 

GOOD God!! That is one bad fucking engine! the heads are a wonder in them selves. I thought my 392 was a bad ass. When you drive this hang on! Very nice i'm jelous.

 

truly amazing... i hope you get out what you put in... it will make the vehicle you put in scoot pretty well

 

YES!!!!!!!! Thank you sir for posting this!!!! I appreciate it and you will be added to the HEMI Tech section. I appreciate the update!!

 

Wow....

Like everyone else, it's amazing...

Now a simplton question....besides alot of elbow grease what did ya use specifically to smooth the block (I dig the look and am pulling my engine soon)

 

Hello Bored&Stroked:

Say nice set up...
I was looking at your Bio to Email you as I have not posted on the Board yet. Have been a Lurker here for quite awhile and remember seeing your earlier posts. Which between you and Hemi Rambler ( hi Jacin) is what coaxed me into joining.
I have a 38 Fiat Altered in progress. 6 years now. Life long dream since Niagara Drag strip when I was a kid. Did not at the time realize how much 9/11 would slow this project down..
It has a 331 in it bored to 354 (+.125) and I am at the point now of having to make a few final decisions on how it will finish. As far as:
Glide (set up in it now)or Lenco(what I want).
Injected-Stroked or Blown stock Stroke.....
I have a set of triple 5's and a set of Donovans on the Bench so one of these will be on the car. Deciding factor there will be if my Titan Rockers fit the Donovans or not.
Have been working hard with my Long time friend to get his BBF-Lenco-Crower injected FED out soon. So my car has been taking a back seat. Plus the usual Dad duties LOL.
So E me sometime. Sorry that I made such a long winded reply.
Thank you

 

Myself, as well as others would ALSO like to hear bout that 331 man! I'm planning a similar build. I'm sure you could shed some light on topics around here and add to the tech section for us... First thing is first though...
http://www.jalopyjournal.com/forum/forumdisplay.php?f=18

Keep us posted!!

 

I've done this on a few blocks - the primary tools I use are as follows:

1) High speed air 1/4" shank grinder. You can buy them all over town for as little as $30. They use quite a bit of air, but they are good for all sorts of porting work, weld finishing, etc..

2) Rough Cutting: Especially when you're just starting out on the as-cast iron surfaces --> I bought a set of high-speed carbide rotary files. You can find good sets on eBay - with a variety of shapes. I probably use a range of "flame" shapes the most -- with rouded tips and probably a 1" or so working area.

I also use hard 1/4" shank stones in some areas. There are MANY grades of stones and most of the cheap ones on eBay are just that. They're made for shit, wear down in minutes and are a waste of time. I'd try to buy some good quality stones for cast iron or steel -- with a larger "flame" style shape.

Basically, I just use the same techniques that you'd use when you port a set of heads --- just a lot more of it!

3) High Speed Disk Grinder: There are some areas where you can use a high speed disk grinder (like the front surfaces on either side of the machined water pump area. You can also use one in the areas between the freeze plugs. I would get one of the smaller ones - with a wheel diameter of 4" to 5". You can use the hard grinding disks ( like you use on welds ) as well as different grades of sanding disks.

4) Head Porting Sand Rolls: You can order a kit from places like Standard Abrasives - you'll mostly use the larger roles. Once you've completed all the grinding, stone and rotary file work, then you'll spend a lot of time with progressively finer sand paper rolls.

5) Hand Work: When I'm done with the above, I also use a variety of sanding blocks and 200 to 400 carbide sand paper to smooth things out and remove some of the grinder variations. I use a variety of rubber blocks - so I can flex the surface to work the sides of the blocks, the transition to the freeze plug areas, etc..

6) Make sure you remove the cam bearings and have the block hot dipped and pressure washed. More the better - as you don't want the cast iron and abrasives to eat your bearings out!


Time: I have somewhere around 40 hours in the block as you see it. That includes about 6 hours or work in the internal valley and oil-pan areas ( for oil flow and to remove casting flash ).

Hope this helps!

Dale


Note: Here is a link to a previous post on just the block prep:

http://www.jalopyjournal.com/forum/showthread.php?t=148597

 

Got a stiffy looking at that...

 

If the Titans were designed for the 392 heads, they will most likely NOT work on the Donovans. Donovan made quite a few different heads - so there are differences between most sets ( and at this time in NHRA history, people were changing things at a fast pace ). You'll probably find that the pushrod spacing is wider ( for larger ports) and the valves are longer -- this usually translates to the relationship between the pushrod cups and the valve tip being quite a bit different between a stock 392 and the Donovans. Also - the Donovans have no provision for moving oil from the 392 deck into the rockers, have no water holes on the deck surface and only have water jackets on the exhaust side. I believe we can get enough water through them to cool on the street ( heck they're aluminum and the exhaust is the hot side anyway ). I'll let you know once we fire the motor. I'll drop you a PM with my eMail.

Dale

 

Freakin' AWESOME!!!! The smooth block puts it over the over the top!

 

Donovan heads don't have oil passages like stock 392's do. What we did is drill the deck surface of the head to pickup the 392 oil hole and route it to the stud. We use the stud passage to move the oil up to the rockers. The rockers did have the standard 392 oil pickup hole ( we put a plug in it as it was hanging over the side of the Donovan rocker mount ). All that hole did was route the oil back tothe stud passage . . . which we did on the lower surface anyway. The RAS rockers already have a oil flow restricter in them, so the top end won't take too much oil. The rockers are running bronze bushings instead of needle bearings -- as Gary at RAS like this approach better for street engines. These rockers do have the small oil passages to bring oil out to the tip of the rocker and valve end -- which is important on the street.

I'm going to add an oil accumulator to the engine - to pre-prime the oil system before start. I'll make sure I have oil pressure to the top end before I fire it.

 

Sounds like you got it covered pretty well. The reason I mentioned the oil was the hemis don't pump alot of oil to the rockers like say a sbc and the oil passage and rockers need to be aligned to get any oil up there. I have an issue on my 392 where the drivers side is not getting oil. It looks like the machine shop did not put the number two cam bearing in right to align the oil passages. Not an easy think to fix once the engine is put together.

 

Oh man! That does not sound good! Sounds like you should be getting some help from that machine shop to make it right! Keep us posted, please!

BTTT for B&S! Worth the bump! Fantastic build!