HAS ANYBODY PUT A DEMON CARB ON A NAILHEAD? I WOULD LIKE TO DO THIS BUT IT SEEMS NOBODY SELLS AN INTAKE THAT EXCEPTS IT.I'VE HERD A 66 INTAKE WITH A ADAPTER WOULD WORK??? o No: THANKS
I'm planning on putting an 850cfm Speed Demon on my Nailhead. You do need an adapter since the factory carb bolt pattern is different. I picked my adapter up from Jegs for $15. It's made by Trans-Dapt, and the part number is 2090. This should work for you as well, unless you have a Q-Jet intake.
Bob,you can take your sq. bore manifold and cut the partitions out from between the front and the rear barrells, leaving the center divider in,,, and it will work much better... but you will still need a adapter plate because of the narrow bolt pattern of the factory manifold...This makes a ''doc dual plane'' as the guys have taken to calling it here on the board....the demon should be a very good carb for a nail... you will also need a free flowing air cleaner for the increased f low and ''cold air pkg. '' if possible.... you can pick up a bunch of hp here if you do it right....:Brow: The years manifolds that will work is the 1959-1966 401/425sq bore manifolds,,, not the spread bores....
Definitely do Doc's mod. It's well worth it. I just finished up the manifold and am going to get to work on the adapter. And like Doc said a cold air package is very beneficial. I just picked up a Spectre low profile "muscle car" cold air kit from Jegs. I think the part number is 728. It's usually $144 and is on sale for $100. Too good of a deal to pass up if you ask me. Also, Doc's said in the past that a good cold air setup is worth about 8% of the total horsepower, which is certainly believable since people utilizing it have picked up 2 tenths in the 1/4mi. Just something to think about...
Thanks alot guys,I order that spacer from the local speed shop and will have it monday.I have a extra intake and will give it a look.Do you have to trim the spacer to? I'm using a MSD dist. and a Edelbrock carb but don't really like the carb.I have a Demon on my 71.Its great!!!Is there any other tricks you might have? Thanks again guys.Bob
I'm planning on trimming the spacer as well. As far as tricks, just do simple stuff like port matching the gaskets. I'd be inclined to think so.
Cris, Pard, personally, i probably would do it , knowing me the way i do.... I really dont see how it would hurt anything,,,,,Buuuut,,, you will change the flow charistics,,,,any time you change something there are results, some good some bad, it took some soul searching to do the first manifold that I did,,,, but it turned out well,,, just dont mess with the center divider....here is a clue,,,,most all the performance manifolds like edelbrock, ect have that configuration....
Very true, in fact the only manifolds that have the 4-hole configuration are the factory iron pieces. By going to the dual plane design (horizontal dividers cut out) you loose a little low end torque but pick up A LOT on the top end. Speaking of intakes, wasn't Eelco suppose to come out with an all aluminum single 4bbl intake for the Nailhead? Seems like I've been hearing talk about this for almost 2 years now.
The Edelbrock B262 is a 4 holer also like stock. I believe the Awfulhouser is a 4 holer also. Wieand is not. The carbs. are closer together than stock. Marty has scrapped the single 4 aluminum intake. Something about not being satisfied with flow results. Has one done I would like him to send when it comes time to do some dyno testing on the latest "Nail" build. Tom T.
Yea I hear ya. I am going to give it a shot. I just happened to get an extra dual quad intake in the trunk of my Riv when I bought it. I figure if I don't like it I can always switch back to the other stock one. Plus I didn't want to have to change my air cleaner setup due to the spacing on the aftermarket manifolds.
Nails like alot of cfm, so an 850cfm carb is perfect. And Tom your right about the 4-hole intakes. I was thinking more of aftermarket performance intakes, rather than aftermarket pieces that emulate the factory DQ. I'm kinda dissapointed to hear about Marty. I'd been looking foreward to seeing the finished product.
Let me ask a OSQ here.... [old silly question] Cant some one just take a factory stock manifold pattern and duplicate the specs except for being out of alluminum and the holley bolt pattern and the 2 oval openings??????o No: o No: :rant: :rant: :Brow: :Brow: ray: ray: Simple, aint it.....
This might be a little off topic but what size main jet are the holley guys running. I have a bog at part throttle with a #70 jet
Maybe since Marty is abandoning the project someone could buy the castings off him and get the project back on track. Seems like an awful lot of work to just say "hell with it". Heck, there might even be a business opportunity for who ever takes it on. And just for the helluva it I send Eelco an email. We'll see what they/Marty say.
It's a holley 850 double pumper with mechanical secondaries and no choke. It also has 50cc acc pump if that makes a difference. I put it on because the carter was leaking and I took the holley off a running car.I put a 76 jet but it ran like junk with popping through the carb so then I put a 67 jet in and stalled/bogged the car so that's why I put in the 70 which made it a little better.So instead of buying jets between 70-76 I just wanted to get a idea.
The Weiand is an odd critter. It has a DIAGONAL passage. Here it is next to the B262. Also, the carb spacing was so far apart my linkage would BARELY fit. Bummer to find out about the Eelco single 4 project. It'd be nice to hear the details how "bad" the flow was. Is he going to send it to you Tom? I wish I could have run the dual Demon carbs. It would take some fussing and working with Barry Grant, but I think it is possible. Erik
