Technical Cadillac flathead horsepower tricks

My vote = 6 carb intake

 

Zig zag, i don't know the answer to that, but when i return home i'll check. Maybe someone else here can answer that?

Russ, thanks for the info- pretty spendy pistons, but good to know if a guy was serious about a race build.For those of you that havn't seen Russ's timing cover built for these motors, you should check it out. Amazing build, and great quality!

http://www.jalopyjournal.com/forum/showthread.php?t=311796&highlight=cadillac+flathead+timing+cover

Here is some additional info, that Thomas Kidd was kind enough to supply.

Any other experiences, stories, or tricks about this engine out there?

 

I don't know how I missed the remaining pages of this post after I posted on page one. The issue withthe Cyclone heads is the head itself, not the gasket. I work for Arizona Street Rods and I am the guy that discovered the problem . There are no holes in the heads for water to get into. I drilled 18 holes in each head as per an original head. The gaskets available, (both steel composition and copper) matched the original cast iron head exactly, and required no modifications at all.

After this modification and reassembly, the problem was eliminated.

And Kevin, as to your first post about this, it was the block not the head that got hot. It only took about 2 minutes of run time to realize we had a problem.

I am in no way knocking these heads as I feel they are a very high quality piece. It is some of the best cast aluminum I have ever machined, and other than this issue, they work very well.

 

I see no comments on the dyno sheet?

Anyone happen to notice the peak power after modification?

The test may have been performed with all the auxiliary equipment attached (generator, water pump, fans, PTO drive) which reduces the output.
Now, let's assume that you're not limited to what they did, that you have more development time and some modern stuff that didn't exist.

However: peak power = 136.

That "should be able to push 250-300 hp" isn't going to happen.

 

Panic,

I did see that. However, on the other sheet, the "discussion sheet, it showed 161 hp with 8:1 compression, and a standard cam.

What am i missing? Two different tests, with different mods? Help me out.

I wonder if Cyclonekevin has any hp tests done with his heads, or if anyone out there has some with Edmunds heads? Anyone running a solid cam that can provide performance data?

It is possible my hp goal is wishful thinking. I'm going to dyno it when i'm done, to find out the results.thanks.

 

Give FlatHead Jack a call.

http://www.flatheadjack.com/

 

that's a good site for ford and mercs, but doesn't do anything for caddys. Thanks for trying

 

A little off topic, but I will say it any way, I recall seeing an English TV program called Top Gear where they were allocated so many dollars to improve the performance of a nominated car, as I recall it was a Renault.

They did more than engine stuff as it had to do a better time around a race track with the improvements added. They pretty well a did a run each time they added an improvement and to most peoples surprise the car went slower or achieved very improvement.

To my mind they should have just added a nitrous kit to the original car, it would have not cost that much and the HP increase at least would have been guaranteed essentially improving the straight line performance at least.

So if we have all the 1%ers covered would it not be interesting to add nitrous to the list of things that would get more HP out of one of these monsters or is it really incompatible with engines of this era?

 

From the outside looking in... if I were fortunate enough to have a running Caddilac Flathead, I wouldn't take a chance with the Nitrous. Those engines are just to rare (and valuable). Heck, even on my '49 overhead Caddy, I wouldn't take the chance of ruining it with nitrous! I am working to acquire a Flatty of my own, so I am not totally removed from this discussion I hope.

 

I don't want to speak for Russ, but I think his point is that if we have covered all the conventional tweaks, all we are left with are the newer, less conventional add-ons.

I'm not convinced that there aren't more that we can do to this engine, and i'd like to hear from some ford/merc guys on what they do.I know that they have more aftermarket stuff available to them, but it sounds as if some stuff is being worked up for the caddy flattie.

 

I don't want to steal this thread, but I have a 1937 LaSalle (Cadillac) Flathead with a LaSalle three speed top loader transmission for sale. The engine came out of a running and driving car. According to the original owner,the engine was rebuilt in 1996 and only has about 3600 miles on it since.
It's for sale. If any body is interested PM me.

 

my hp goal is wishful thinking

No, just a bit too optimistic until we know more.
You can use more carburetor that they did, but it means carving up an old manifold or making one. Yes, there are people who do that - it starts at about $2,500.
The stock cam is going to kill anything, and with no rocker arms you're limited to the lobe. Regrinding the stock cam can't re-locate the lobes so the LSA will be almost the same. Lacking any real data, the most practical way to get cam info is to supply a bad one (broken, blah as long as 1 intake and 1 exhaust cam are still good) to a grinder who will work with you. Dema Elgin might do you some good.
I don't think the differences in chamber shape are going to do much, and remember that the heat (= power) loss through an aluminum head is a big deal.
Many of these things are cured with money - can you afford a 250 HP $10,000 engine?

 

Wow, cool thread. I have learned so much more about a flathead Cadd, than I think I ever wanted to know. Its too bad I gave up my 346 Cadd.

 

Palle, do you have an intake for that blower? If so, would you post a pic, or pm me?

Anyone have more tech data or ideas they can post? I know there are a lot of flathead owners we have not heard from, and a vast amount of knowledge out there that could be shared.

Thanks

 

buddy..i am sorry but i dont. the italmeccanica was 'just' sitting on the burrell intake! lol!
somewhere i have some pictures of a blown caddy..i'll post them when i find them!
-palle

 

Thanks Buddy, yes that is what I was implying and also wanted to say some things are not going to be worth doing as the HP return may just not be worth the trouble.

Privately, I believe we have spoken before about thermo fans and electric driven water pump, all these kind of items that take HP away.

Consider the use of an electric gas pump over a mechanical unit so save a small amount of HP.
I am lead to believe the mechanical unit chews the front cam bearing out earlier than we would like.

So some improvements may give you small gains in HP and also provide better reliability, another example of this would be the ignition system up grade and the twin exhaust as I believe the original cross over exhaust caused vapourization in the heat.

Just my thoughts!

 

Hi all.
Wayne from Oz. Re HP tricks for the Flatty Caddy.
I've spent some time thinking on this, probably should have spent that time working on it ! As usual, other projects intervene.
I'll be running a T700 behind mine with Jag IRS & 4.10 gears ( 29 in tyres) & don't expect a world of performance, that's not the point, "difference" is
When I first got the mill, some years back now, I spoke with Uncommon Engineering. He was familiar with the motor & estimated he could build/supply a Potvin style, front mount 4/71 blower for around $5K US. When you check his site out you'll see he has an alternate point of view & for someone on the ground in the U.S. it might be worth following up, both re blower & girdle. Bet its more than 5 K now but it's sure a one hit solution in the power stakes !
That aside, I've an Edmunds intake & plan hefty shave for compression bump & adapt distributor to modern electronic version and headers to suit my vehicles style.
The most telling article I've read was the Ak Miller story re results from Winfield grinding a cam so that too is on the cards but makes adjustable solid lifters near mandatory.. anyone have a lead on such ?
I've a pal who regrinds cranks,strokers, & had thought of that as an option but with the increase in piston speed, pitifull oil pressure & the reduced shank, for oil passage, on one of the rod bolts I'd shied away from same.
Carb wise I'd thought Rochester though we have a 90's model inline 6 Ford down here which in its base model ran a 2 injector set up on what was basically a carby manifold. From 3 feet away it looks like a 2 barrel carb. Combine with a basic comp like a Wolf & it could be interesting though in itself, not a great HP contributor

Realistically then, with modern hi octane ratings ( as compared to the 70's & 80 octane ratings they ran back in the day ), compression & ignition to match same, duals, porting,perhaps some relief work between valves & bore, electric water pump (Davies Craig ) headers & cam, 200 to 220HP/ 4500 to 5000 rpm tops ( perhaps a tad more) has to be a realistic HP / rev target otherwise we'd be running sbc's & windsor's et all but then where's the fun, that's why my youngest boy keeps measuring up his A model frame & the big old Chrysler straight 8, 385 cubes, & muttering about extended chassis ! He could build two 400HP 351's for his coupe for the $'s it'd cost to get that Chrysler to turn over !

Even with a blower, 250Hp would take some serious work just given the basic design of the engine though I still cast an eye over that polished Paxton every time I walk past it peeping out of its box, split the air feed & run two top hats on the Edmunds for a blow through application.
Local tech guru keeps muttering about turbo's when he sees a Flatty Caddy (something about maximising return from their high heat loss) but I'd rather be blown besides, turbo's seem out of context )
Problem with "guestimating" potential power outlets is what is our base starting point. I've read the stock civilian models as 150 /155 & seen military versions ranging from 120 to 143, let alone some of the documents posted here, showing levels in between & 160 lightly modified.. I've just "assumed" 150 as a base
Cheers all.. Great thread & I'd be really keen to hear if anyone has feedback re adjustable lifters or contact with Uncommon Engineering .
Wayne

 

Hey Wayne,
are you converting the original dizzy with an electronic kit,
or are you modifying a chevy dizzy to fit the caddy?

I'd like to lower the heighth of the stock distributor stand,
just for firewall clearance issues,
but was thinking of modifying a newer distributor to fit before I spend the time figuring it out,
especially if there is better performance and parts availability.


I've been watching this thread studying all the tricks,
but don't really have anything to add but more questions!

Thanks guys...

TP

 

Thanks for you input Wayne, we are glad you could join the party.
I hope to catch up with you some day soon.
That injection thing sounds interesting.

 

Hi Zibo.. re the Dizzy.
Ist up I thought about a Mallory dual point that was on ebay but upon talking to the Mallory guys in the US, left it alone. Their recomendation being to cut & shut a modern head to a reduced Caddy shaft. There is a local guy who does such so that will be the route I take.. should also be able to lower the overall height this way.
Upgrading the internals is an option but I think 1) it's more of a compromise & still relies on the old Caddy distributor hat, bearings etc 2) I'm not restoring this unit, so original look is not the watchword 3) want the lower height & finally, if the only mechanical change is to splice the shaft then I much prefer to maintain the integrity & serviceability of the complete modern head unit.
Regards
Wayne

 

What happened to all the potential blower talk that I was expecting?

 

There is a lot of really good stuff here, and i'm sure there is more to come. I'm pretty sure there are still some tweaks/tricks that we havn't heard yet, and i'm anxious to here them.

Here is some info to modify the heads for higher lift cams,and test, sent to me by Thomas Kidd.

 

If anybody has some good info about flathead Cadillac engine using blowers this would be the time to start posting it.

 

there you go Russ!!
-palle

 

Russ, maybe this will answer a few questions. While I don't plan on a blower for this motor, i've kicked it around for my next build, although i'm working on a different intake for it, that I will probably go with. I'll post that info later. I'm pretty sure I could build the intake, but thought i'd see what the pro's would say. I contacted Uncommon Engineering, and asked if they would build me an intake manifold. Here is the answer, for those interested.I've asked about expected gains, and will post when I get an answer.

<TABLE class=messageListTable cellSpacing=0 cellPadding=0 width="99%" border=0><TBODY><TR><TD class=messageSubject colSpan=2>Re: 4-71 INTAKE <TR><TD class=headerLeft>From:</TD><TD class=headerRight id=fromValue>Uncommon Engineering <[email protected]></TD></TR>[email protected]
<TR><TD class=headerLeft noWrap>To:</TD><TD class=headerRight>[email protected]</TD></TR><TR><TD class=headerLeft noWrap>Date:</TD><TD class=headerRight><SCRIPT>document.write(DateFormat.FormatDate(new Date(1234796911000),"E, d NNN yyyy h:mm a"));</SCRIPT>Mon, 16 Feb 2009 8:08 am</TD></TR></TD></TR></TBODY></TABLE>

<TT>Hello,Yes of course we can create a casting for the Cadillac 346, would need astock intake manifold to pattern from. Engine would benefit from customsteel main caps, a girdle would require extensive pan modifications andadditional expense.I would only be interesyed in supplying an entire blower kit for the engine,with water pump and generator drives designed integrally. Everything wouldhave to be hand built, crank hub, vee belt sprockets, intake, generatormount, etc. Ballpark around $7,000-$7500 for the blower kit, and the maincaps or girdle would be done on a strict T&M basis.</TT></PRE>

 

Hey wayne,
wondering what donor distributor would be planned or suggested in your conversion?
An aftermarket or a stock one?
The stock vacuum advance is so simple,
but I'm not really sure which distributors would have similar advance-curves.
Thanks!

TP

 

More on having a blower system built. When the estimate comes in, i'll share it, but it's pretty clear already that this is not a viable option for most, unless we did it ourself.

From Uncommon Engineering:

Buddy,

I expect, if I built the entire engine myself, choosing the valve sizes /
angles, doing the porting / bowl work, fitting aftermarket rods and forged
pistons, having a cam ground to my specs, etc. that I could readily make
about 325 BHP from that platform, on gasoline.
----Steve

 

Thanks Palle, I just love those 4 pipes out each side.

 

OH, GUYS. HERE'S THE PRICE OF DOING THE BLOWER MOTOR. IT WAS JUST SENT TO ME, AND IT IS WAY OUT OF MY LEAGUE!

From Uncommon Engineering:


I would ballpark it in the $17 K range, with custom designed and constructed
electronic ignition, vintage carbs, custom fabricated tubing headers,
running on the dyno at my shop.

 

What about intake manifolds? All i've seen are the stock ones, and 2x2's.
I'm working on a tri-power, that i'm planning on running. I'll post build pics later. If it works, i'm going to build a blower intake for fun, but i probably will never run it!

Anyone have pics, or is anyone running anything besides stock or 2x2?