Blown nailhead knowledge needed

I am looking for knowledge on 364 nailhead build running a 471 blower . I found a lot a information but not a lot on running a blower. I know very basic knowledge such as I have to drop compression down to 8-1 but other than that I'm a little lost. Any help would be greatly appreciated

 

Building a nailhead blower is like building any other blower motor.

I build them a little different than what most of what you are going to hear. A lot depends on how much boost you intend to give it. A lot of the fellas arwe real happy with 3 pis I wouldn't run less than 8 and still think that less than 12 you are fooling yourself. But that is a different story all together my opinion on boost is not what you are asking.

I usually like to use a forged lower end, o-ring the block and dedicated blower camshaft (it may have longer duration on the exhust side). Broad flat faces on the vavles and use stronger springs on the intake side to keep the boost from overiding them.

I prefer two four barrels to several two barrels but I love the look of six or so two bbls. 2x4 is easiler to tune and in my limited experience will perform better. For injection I like Enderle barn doors, but I am building a street engine for an off topic car that has an electrified hat injection. I know that several if the fellas have had good luck with a 4 port hilborn setup. Granted other than the electrified hat all of the mentioned injection is basically a race only setup.

No help correct?

 

I wonder if the heads (small valves) on any nailhead can benefit from boost of more than just a few pounds.

 

Nice info. I will be following this for sure!



BloodyKnuckles

 

Tommy boosted the hell out of them, but he had a nail head wizzard rework the heads. Maybe it will take a lot of duration to optimize the ammount of time it has to fill the cylinder. If you shove it hard enough it will go.

 

Have you guys heard of using the exhaust valves for intake and vise versa? I know you have to custom grind the cam. What's the big benefit? I read an article a few years back but would love to hear comments on this.



BloodyKnuckles

 

You have got to check this out.
http://www.jalopyjournal.com/forum/showthread.php?t=669332&highlight=nailhead

 

I was going to run multiple 2 bbl set up. I'm trying to keep in a 1958 period and was going to run a vbelt set up instead of 1 large belt . The nailhead is going in my 30 coupe. Thank you guys so much for your help. Keep the knowledge comming

 

What is your plan for the motor? make power or look cool? That 4-71 will take a lot of spinning to make boost as it's a small blower. Nailheads like carbs....2x2's might give you a really lean situation and could cause bad things to happen inside.
I'm no expert but working on putting together a 425 with a 8-71.
Nailheads = awesome
blowers = awesome
perfect combo.

what are your plans for an intake?

 

carmen faso in New York, he was doing blower stuff in the 70s and is the nail head expert 716 693 4090...he is a good guy can supply parts and shares knowedge..and totally computer illiterate..150%

 

All nailheads have forged bottom ends.

Yes he did.

We've had multiple conversations about this on the Yahoo Nailhead list and it really doesn't pay off. Theoretically it sounds good, but it creates oh so many other issues. Like manifolds.

Correctamundo. I would say you are correct, you'd need a bunch of 94's or 97's, maybe 2G's could be used and still give that look. But a couple of 4 barrels would probably make her happier.

And he will talk you rear off about it if you call. Great guy, I don't believe there is ANYONE that knows more about Nailheads.

 

http://www.buicks.net/shop/reference/blown_buick.html

This is in the link I posted, but its about 3 surfs in.
From 1954

 

I always thought that a blower was the cure for breathing, low compression, exhaust and a mild cam - the more boost, the more it will push past small valves. Adding valves, head work, cam, exhaust just makes a good thing better!!

The problem is keeping the bottom end in one piece due to the extra power the engine will produce.

 

Restrictive heads will cause a higher boost pressure in the manifold than free flowing heads.

 

build it tame enough and a stock motor will survive
it won't produce the peak numbers a dedicated setup will
but it will boost above stock

hot street should think about 6-71 with two fours, forged pistons
and everything suggested above

and above all assembled meticulously

 

That is actually correct...pressure is nothing more than resistance to flow. Pressure and flow are inversely proportional..

Yes, a better flowing set of heads will show less boost pressure with a given amount of flow than a pair shitty set of heads. What that means on a real street blown nailhead is basicly nothing. Build your engine with the same general guidelines you would for any blown engine and don't get too wrapped up with the physics.

Build a nice forged piston 8:1 engine with a decent set of rods/crank and a bumpy cam stick the blower on it and go have fun. Keep it under 10#s of boost, mind your timing and fuel ratio and your nailhead will live a long time and whup all the Chevvies.

Good luck, -Abone.

PS. Hit the search button for lots of generic blower info and score a BDS catalog, it has a great tech and question and answer section.

 

don't forget to use a fuel with octane to suit.

You could easily end up with an effective compression ratio of 12:1, thus needing some high octane race fuel

or run E85

 

All above is good advice. I'll add that less than 5PSI isnt worth doing, a 471 at probably 5% or 10% over should work out for a street motor. I am also a huge fan of the MSD BTM ignition box. I also like to run a little more compression than alot of guys do Im running 8.9 to 1 on 93 pump gas for street driving and 6-7 PSI of boost. Also a 2 inch Gilmer belt would also beperiod correct.

 

Who on earth would be dumb enough to put a blower on a Nailhead anyways?



Rookies.

 

I wondered if you would chime in as you have maybe seen one or two in your day...


-Abone.

PS. Don't you still owe me a shirt????

 

Thanks for all the information guys .I did hear a rumor of a guy in buffalo who builds nail heads thanks for the number . Figures I move from buffalo and the guy I have to talk to lives there. I got some thinking to do and maybe I'll be the one on earth stupid enough to put a blower on a nailhead.

 

Chuckles that damn strange bird is the reason I got this bug up my ass to build blown nail. Strange bird is gonna make me go broke. Oh well there's always Ramon noodles for the next 10 years haha

 

Probably the single biggest hurdle in this whole thing is finding a 364 blower manifold. ANd people think the 401/425 ones are hard to find. If you have one, or a good line on one you are more than half way there. Seriously.

 

Well if nothing else you'll have one of the coolest looking motors ever

 

Well I did recently talk to hamptons and he said they would have no problem building one I guess he just finished a 401 nailhead blower manifold for a customer

 

Thanks Paul

 

Hampton just takes a Offy manifolds mills them flat then welds on a 1/2 thick plate.


Weiand made 20-25 blower manifolds in 1959. Theres talk of some being repoped soon.

JE or Diamond for forged pistons. Diamond is making mine for my stroker motor and if I like them I will have them make some for my blower motor when the time comes.

 

Awesome, then you don't have to worry about the flow in the heads since it'll be worse in the manifold.

 

DOH!! that's gonna leave a mark

 

they use offeys because theres nothing in them..its just an open plenum..not great carbed..but you dont need anything in there when force fed...the supercharger will over come any resistance....