Small Block Chevy Intake Question

[Docwheelhorse 2,560]

Hello All,

I picked up my 1971 Nova SS and it really is beautiful... It needs a few minor things (gas gauge effed up, knobs missing here and there etc... nothing major). Anyways... it has a 400 small block that supposidely has been bored out .060 which would make it a 412, I do not know the cam specs but it has a slight thump to it. Engine runs good, doesn't run hot and sounds nice. It has a Mallory electronic ignition conversion in the stock distributor & it is running cast iron "log" exhaust manifolds into the factory 2 pipe in, 2 pipe out dual exhaust muffler. I couldn't be happier that it is running this setup as I am sick of fighting headers and the associated exhaust pipes etc. -----BUT----- the previous owner in his infinite wisdom stuck an Edlebrock Victor Jr. 2500---8500 rpm intake with a 750 Carter AVS on top of the motor. This setup HAS to go.... the low end grunt just isn't there because of the big single plane manifold and big carb. Once I'm up on the highway turning 3600 @ 70 the thing wakes right up and will throw you in your seat from 70--100. The car has 26" tires, a muncie M21 4 speed and 3.73 12 bolt posi---SO 100-105 is when you run out of engine because its past 5000.

All I want ot know is what factory type (cast iron or alluminum) intake has anybody run and been happy with. I have a 300 Hp Cast iron manifold and Quadrajet off of a '68 Camaro that I considered putting on.... I have also read about the Chevy aftermarket ZZ4 alluminum quadrajet intake that supports 350 hp and 5500 rpm's, I also looked up the Edlebrock performer and performer air gap which are made for idle--5500. I'm all done racing.... this car is 40 years old and I just want a nice solid driver with a decent amount of giddy up for when I get rambunctious.... The other motivation is that this Victor Jr/750 Carter LIKES FUEL.....

Thanks and sorry if the post is long winded

Tony

[chris11 184]

That manifol dosnt have a cross over. so you should have one in the exhaust before mufflers, also i have good luck with setting up the edelbrock cars. i have all the set up kits for them. Dist. vac advance ? or just weights? Dont forget we could put it on our dyno at work for you.

[smoreau 658]

I know what you mean with the setup that you have isn't a sunday driver. I like the quadrajet carb and the chevy aluminum intake you mentioned that will fit that carb sounds like a great combination for power from 0-5500 rpm and better fuel millage when your not into the secondarys. just my thought and the choke would work as it should.

Scott

[horsefeathers 15]

Doc, That Nova is a cool street machine!

Sounds like someone was drag racing it with that combo.

The m21 with 3:73 gear will work good on the street

With a lite Nova a 3:55 or 3:32 will give power and econmy.

That single plane has to go!! no good on the street!

Edlbrock Air Gap is a great choice!

Dump the AVS for an AFB or Holley 650

Rodchester spreadbore is a good econmy/performance carb.

But I like a squarebore carb!

I agree headders flow but they sux tooo!!

May want to step up that dist also!

:woohoo:

[Docwheelhorse 2,560]

Thanks for the replies!!! I am doing my homework and will have to decide what I want to stick on there. I did have a cool Corvette iron manifold with the old school oil fill in front of the thermostat... wish I had kept it---it would of been great on this motor. Edlebrock makes them new in alluminum with the tube... I may have to just get one. I'm also looking into a dual snorkel factory type air cleaner... man do they look

Chris... if I come up to your dyno and run the car through the gears and find out its making 16 hp @ 3600 just like my Kohlers I would have to cry.... lol

My seat of the pants dyno says this thing is making AT LEAST 1200 Hp!!!

Tony

[horsefeathers 15]

Doc, 1200 horse is a good start... you can build from there!

HORSEFEATHERS!

[chris11 184]

tony i think i may have a manifol for you. ill look this weekend bud.

[Kelly 1,028]

I have used many Performer intakes on small and big blocks very happy with them, but I like the performer RPM best, and I'm fond of my holleys, but a good quadrajet is hard to beat, they are a little less picky.

[Martin 2,130]

im with kelly on the performer rpm. my gm sedan back home has one on a 383 with dart sr heads and torque cam and it had all the power/torque right where i needed it. was running a 700dp holley on it though. man i miss that thing. i could pull that 3000 rpm converter up to 3400 for some fun launches and let the torque do the rest. it was all over by 6000 but then it had highway gears to take advantage of all that 490 ft of torque.

nothing like a good combination of matched rpm parts.

ran all over my brothers 400 with victor intake.

[horsefeathers 15]

You said so much Kelly!

Holley's are great carbs but tuning them is...

Well... you better know what your doing!

Power valves are the first thing you need to get right !

Meetering blocks, reo pumps, air bleeds, and cam profies!

You need to know what all this does and how it affects each cange!

It ain't easy... But allows for very fine tuning if you know how!

There's a lot going on here!

HORSEFEATHERS!

[shorts 182]

For regular street driving, I'm a big fan of the factory iron Qjet manifold from a pickup or better yet find one off of a Mercruiser, then set up a Qjet to work right on it.

Q jets are a Time consuming PITA to tune initially but once you get them right you can forget them they are nowhere as fussy as holleys.

I run a sbc 406 in the jeep thingy with the hot factory hyd cam retarded 7degrees for a total of 8degrees BTDC to bring in the torque @ 2200 rpm, have a stock HEI distributor spun up to check the advance curves and run that, it's all you need to about 6000 rpm and the cam falls on it's face @ 5200 so your good to go. the other thing I like to do is run stock pushrods under studed roller rockers and good springs with the reasoning being that stock pushrods are cheap insurance for an overrev :D

[horsefeathers 15]

Shorts, Is it a good idea to build a weak link in an over head valve engine?

I see where your going here.. bend a push rod oposed to breakin'

a rocker, spring, or dropin' a valve.. Kaboom!

If it works for you then OK man!

[shorts 182]

I can change a pushrod for $2 and about 10 minutes, a whole lot easier than anything else in the engine, unfortunately my other weak link is the front axle stub shaft when'if the front end bounces under a heavy pull, no room for excessive brain fade :woohoo:

[littleredrider 408]

I've had a lot of 400s, and loved them all. I used a Performer on one that I had with a holey 600, drove it back and forth from Bing NY to Ottawa Canada for 6-7 months, put 60k miles on it, only ever had 2 things go wrong. One, the tranny went, that was my own fault. Two, every now and then I would break a rocker arm. I had a set of stock 883 heads with stock springs, but had a cam with .480 lift, which is also the limit for coil bind. I could change the arm in about 5 minutes.

I'd think any stock or dual plane aftermarket aluminum intake would work better than the single plane.

Also, try to put a 600 carb on and see how it works. Better fuel economy, better response too. I had an Edelbrock 600 on a 454 that i had in my old truck, thing had crazy torque. Don't need a 750 if your not gonna be turning 6k+ RPMs.

[alco2nr 0]

Doc, I just gotta stick my oar in.

1) yank out the BA and put the 307 back in. Put on 72cc heads, 1.94/1.60 valves, Edelbrock 360 dual plane & carb. RV grind cam (.420/262) flat top pistons, stock HEI 8 degrees initial. It'll whistle to 7000 all day long and give you 20-23mpg.

2) Sell the Muncie and get a Richmond super T-10 with a 3.42 or 2.88 1st gear. A wide ratio trans works best for the street. The low 1st gives you a wicked hole shot while 4th stays the same. For a little more money you could get a Tremec 5spd or a BW T-56 6spd. The OD is great for mileage.

To the "mountain motor" fans, you might look up stroke to rod length ratio and what effect is has on the torque curve of an engine. Giving up some CID might not hurt as much as you think. I'll just duck now

P.S. If cost is an object concerning the intake manifold, I have a stock GM aluminum 4bbl intake which you can have CHEAP (it won't fit my Wheelhorse) I'm pretty sure it's from a 5.0L. It has black paint on it ( No fill tube-sorry) I also have a 1971 307 shortblock which I have been saving for the crank.

By the way, Shorts; that's the first time I've ever heard of someone using pushrods for fuses! makes sense, though!

[Docwheelhorse 2,560]

Hello All--

this reply is being posted beach side on Myrtle Beach SC. Yah gotta love these netbook PC's and Verizon mobile broadband for $35 a month!!

Anyways... I have decided to purchase a 1968 Corvette iron quadrajet manifold complete with oil fill tube port drilled in front. Manifold has been magnifluxed and oven baked so it should be a "paint it" and bolt it on proposition.

I have a 1968 Camaro 275 Hp Quadrajet off of a manual transmission car that a very good friend is going to go through for me. I may up the secondary rods a size or two but will start with that and see how it goes.

Finally I plan on purchasing either a Corvette or Camaro dual snorkel air cleaner (Novas never had one...) . I'm going all for looks and simplicity.... My father who was a mechanic for 40+ years always told me "stock is best" and after wrenching on many different cars, boats and trucks I have come to agree. Racing parts are great but man they can be a PITA....

This car is 40 years old and her racing/fighting days are behind her. If I want to beat on something I will pick up a late model Camaro and pound the stuffing out of it. They where Ugly anyways (the 2002 and back ones... I don't know when they started)

Thanks for all the Info and thoughts

Tony

[shorts 182]

something has to be the weak link and after having 3 MSD boxes and rev limiters leave me stranded its back to HEI with a hot coil and cheap pushrods

[Docwheelhorse 2,560]

Alco2nr--whats a BA that I have to rip out Unless you shortened "bast***" anyways--I know the 307/2 BBl is a repectable torque motor but that will be the day that I build a 307 for anything. I do have the numbers matching 350 to this car and it has been fully machined (.010 over bore, cam bearings, hone job etc...) along with machined crank, re-sized rods, mounted pistons blah blah blah. The motor was just never assembled and I don't know why the project took a turn and ended up with the 400---except for the bigger is better scenario. If I need too I will put the 350 back together and never look back.

Tony

P.S.---this car won't ever see a motor turning over 5000.... 6 and 7000 are scary numbers espescially with a clutch. A friend of mine grenaded a clutch at speeds like that and it went through the bellhousing, up through the floor, up through the dash and out the roof. As a matter of fact it might of entered low earth orbit and stayed there. He came close to meeting his maker in his 69 El Camino that day and it was technically his fault. He built a 327 screamer but used a stock clutch and no scattershield.... another case of pour all the money into the motor for all the HP but NO SAFETY features.

[Sparky-(Admin) 19,593]

Alco2nr--whats a BA that I have to rip out .

BA = Boat Anchor

Mike............

[Docwheelhorse 2,560]

Thanks Sparky...

Holy Cow a mildly built 400 is a Boat Anchor but a 307 with a few speed parts is the cats meow??

Tony

[littleredrider 408]

Wasn't quite sure what the BA stood for either, but I'd rather have a 6 popper than any 307. THOSE were BA's. Anyone that I've talked to about building a 307, none were any better than before the rebuild, regardless what was done to the motor. They only made them for a short span for a reason....

Every 400 I had ran great. I had one that had to had well over 100k, I put another 60k on it, still ran great. These get a bad rap cause people put 350 head gaskets on them and wonder why they get hot.