Does anybody use this intake? I'm also considering a 850 demon carb. It's going on a 496BB 4 spd car. What is everybodys opinion on this intake and carb combo? Is the Demon carb street friendly?

 

The Air Gaps are excellent intakes..they always make good power.

Buuuttt.......they were designed for 454" sized motors...that 496 will be working it pretty hard. It will make incredible low and mid range power, but it will be down at the upper end over something like a Victor Jr single plane. A 496 makes tons of low end power anyway, the biggest issue is trying to feed them as RPM climbs so you don't end up with a great big motorhome or tow truck motor.

Again, the Air Gap is one of the best out there and will run well, but give us an idea of what the rest of the combo is. Is it a hyd cam...solid cam..roller? How big? What heads.....what compression....what gears?

What do you really like to do with it? If you are never revving over 5500-6000 rpm with hyd stuff the Air Gap will do best probably. But again with a 4 speed and nearly 500", you aren't going to be in lower rpm ranges very much....it's going to rev right through that stuff quickly!


My personal opinion is that the 850 is too small for a 496, and especially on a dual plane intake. A dual plane intake only allows the motor to see *half* the carb on every stroke, so it responds well to a larger carb. I'm not a giant fan of the BG line of carbs, but many are. They do work OK overall usually though. I prefer the HP Holley carbs. The 1000HP is a hybrid deal that Holley builds and it works VERY well on engines in your cube range. It's not a true 1000 cfm carb....but again..it works well and is easy to get tuned. One buddy got 18.9 mpg out of his C-3 with a hyd roller 540" motor using a Tremec O/D and 3.08's. So you know it works Ok at low speeds if it's clean enough to lug down that low with those gears!

JIM

 

Thanks Jim, I may have been talking to you before about this motor. I was thinking of going with the cam mentioned...if it was you. I think it was the Comp cams Hydraulic roller 288R.About 620 lift and about 234-244 @ .50 lift. I have nicely ported 781's, h-beam rods, SRP pistons,Eagle crank,about 10:1 compression all under 6500, it's all at the shop now.It will essentially be a nice street car with the occasional 1/4 mile trip. I'm also running 3:73 with a ST-10 4spd. A TKO-600 eventually when the wife isn't looking....lol.

 

Probably was me.....but I was probably leaning toward the 288R solid roller...not the hyd one. That's just me...I like solids. 6500 rpm is out there for most of the hyd stuff on a big block.

There is a new solid flat tappet out there made by Harold Brookshire (designed the Lunati Voodoo's and used to own Ultradyne Cams). He has a new cam Co. now. Anyway it was specifically designed to offer similar manners and better power than the Comp 288. He can do it because the 288 isn't a real radical cam by any means so it can be done on a solid flat tappet too. His version is actually a good bit *hotter* on ramp speeds yet keeps same adv numbers etc. Just thought I'd mention it to you.....might save a few bucks over either version of the rollers.

JIM

 

I'm looking for the most HP I can get while maintaining street driveability. What are the spec on his comparable cam?

 

I'll have to shoot him a message. He hangs out on the Chevelle Forum a lot.

You can get more power for sure than either cam...just gotta draw that line on how much you're willing ot give up to get it!!

JIM

 

Here's the scoop on it from Harold. As you can see...he's managed to build a flat tappet that can compete with and probably put do the mild roller with respect to power AND driveability.

JIM


I've finally designed something, now I just have to make it......
A solid flat tappet replacement for the Comp Cams CB-288a-R10 their 11-692-8------
CB-288A-R10 288@.015 246@.050 158@.200 .622" valve lift 38-70-78-30
UDHarold's 285@.015 249@.050 161@.200 .618" valve lift 35-70-74-31

Their cam sells on their web site for $363.67, and the -8 in the part number means it IS NOT a steel billet. Lifters cost a good amount, too.
My cam will be a standard high-quality proferal cam--what solids have been made of for 30 years--and will cost around $168.75. Good Americian-made mechanical lifters are available at less than 25% the cost of solid roller lifters.
My cam stays .0176" away from the edge of the lifter, and I have had other cams that get closer to the edge go 100,000 miles on the street. The seating velocity is the same I have used on those 100,000 mile cams. Valve lash on mine is .018", on the Comp .020".
Because of changes in oil quality over the past 10 years, I would recommend using a lot of caution in breaking in ANY flat tappet solid or hydraulic cam.
The Comp Cams is symmetrical, mine, as always, is unsymmetrical. Look at the timing differences at .015"---My cam has a 4* longer power stroke, meaning more torque into your crank at ALL rpms, and a 3* later intake opening point, for less reversion and higher port velocities, again at ALL rpms.
At .050" and at .200", my cam is 3* fatter---Not only is it filling the cylinder faster, it has MORE time to do it.
The result---MORE POWER everywhere.
Now to get you guys some made......

Harold"

 

Jim,
I saw that text by Harold somewhere else not too long ago but I didn't know he'd started up a new company. What's the new name & do you have contact info or a website I can look at? I'm not in the market right now but I get hit up for advice alot & I'd be happy to send some business his way. I love the Ultradyne I'm running!