Best manifold and carb

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Barefoot
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Best manifold and carb

Post by Barefoot »

I have a 76 Interceptor with the 7.2 engine what's the best carb and manifold for the car as mine is a bit tired now.. I am currently in the States so would a new one be cheaper to buy here that would fit?
Steve Prince
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Re: Best manifold and carb

Post by Steve Prince »

Barefoot wrote:I have a 76 Interceptor with the 7.2 engine what's the best carb and manifold for the car as mine is a bit tired now.. I am currently in the States so would a new one be cheaper to buy here that would fit?
I doubt that you have worn out the manifold. Can you not just fit an overhaul kit to the carb?

If you want a bit of an upgrade you could go with the Edelbrock Performer carb/manifold AND cam package.

Beyond that it gets complicated and personal.
taximan
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Re: Best manifold and carb

Post by taximan »

I fitted the Edelbrock 1406, plus performer camshaft, the manifold change would have made little difference unless I fitted tubular headers also, as I had no intention of doing so the manifold was cleaned and painted before refitting. my car gained a few missing horses with these upgrades and refurbed heads, which ones made the most difference I couldn't tell you, but I now have an engine that starts first time every time with electric choke that gives me fast idle until I touch the throttle, a nice even idle and good response to the loud pedal, if I kickdown to first it's like being in a race car!
Shaun.
VAUXHALL VISCOUNT 1969
MB W213 220D
MB E Class Cabriolet
JOC Member 9052
Barefoot
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Re: Best manifold and carb

Post by Barefoot »

Taximan

I am going to do what you have done I think they will be cheaper to buy here in the states what exactly will I need a spacer kit maybe, what cam is it exactly plus should I get an air filter to fit? How easy are these to fit on my car?

Kev
ade1030
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Re: Best manifold and carb

Post by ade1030 »

I would rebuild the engine fully using by mild-perf parts to the result of well-balanced combo for street use (CR 9 to 10, Magnum spec cam etc.), but if you originally intended to change only carb and intake manifold, I would suggest you to buy 750cfm carb only (like Eddy 1411 w/ electric choke) and use the suitable spacer between manifold and carb. It doesn't benefit much to change the aftermarket manifold to an old tired engine unless you rebuild the whole engine again..

Comp Cams has better selection of camshafts than Edelbrock. I use XE268H, Eddy Perf-Plus was too mild for my combo while RPM is for high-perf use.
Last edited by ade1030 on Wed Dec 11, 2013 12:20 pm, edited 1 time in total.
Interceptor III J-series 140/5911
taximan
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Re: Best manifold and carb

Post by taximan »

http://www.edelbrock.com/automotive_new ... r_bb.shtml" onclick="window.open(this.href);return false;

http://www.edelbrock.com/automotive_new ... rmer.shtml" onclick="window.open(this.href);return false;

Which carb you go for with a 440 may be different to mine (383) as your original carb is I'm sure different to the one fitted to mine in 68.
Others maybe can advise on the cfm (airflow) you need.
Shaun.
VAUXHALL VISCOUNT 1969
MB W213 220D
MB E Class Cabriolet
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mustbemad
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Re: Best manifold and carb

Post by mustbemad »

Personal experience with the 1406 and standard manifold on my 7.2 was that the spacer meant you couldn't get a decent heat insulation. The heat from the cast manifold (which keeps a lot of heat in) was transferred directly to the carb, so I had quite a few vaporisation problems. (Not enough underbonnet clearance to have spacer and insulator together.)

The Edelbrock manifold meant I could put proper the proper insulator in, was £150 secondhand, retains less heat when you switch off, and maybe adds a bhp or two even without any other changes.

Really glad I fitted it!

Gerry :mrgreen:
Found a III, now I know the user name is correct!
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bkbridges
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Re: Best manifold and carb

Post by bkbridges »

Barefoot,
Your cast iron manifold has a floor jet EGR system built into it, so any replacement will need to have that feature if you intend to retain it. That pretty much leaves you with the Edelbrock 2191 intake (about 220.00 USD) The air gap version of this intake will not fit under your hood. While cast iron intakes do not "wear out" the EGR porting in the stock intake can crack badly (mine did) and leak, both internally and externally. The cast iron also weighs a lot.
If your car still retains its catalytic converters, then it will need a lean burn style carb to keep them alive and functioning. Your Thermoquad carburetor is actually quite good and can be rebuilt to as new condition if its not too hammered now. Its hard to get better performance from a different carburetor on your particular low compression smogged out 7.2 There are specialists in the states happy to rebuild your thermoquad but Summit racing ( http://www.summitracing.com" onclick="window.open(this.href);return false; ) in the US now sells rebuilt Thermoquad carbs for under 300.00USD. Just make sure to get the correct p/n as all TQs are not equal. Heres a link to the TQ mega info page and identification guide: http://www.moparchat.com/forums/showthread.php?p=591862" onclick="window.open(this.href);return false; If you've already ditched the cats and don't care about the emissions features, then your options are somewhat better performance wise. I would highly recommend getting a new ignition in place (if you've gone non-stock) as your ignition, if original, is set up for a lean burn style fueling/ignition strategy and will be holding any potential performance upgrades back. I would still consider the rebuilt Thermoquad and Edelbrock 2191 intake as worthy companions for a set of closed chamber 915 heads for real gains in torque and power.
BKB
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Steve Prince
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Re: Best manifold and carb

Post by Steve Prince »

ade1030 wrote:I would rebuild the engine fully using by mild-perf parts to the result of well-balanced combo for street use (CR 9 to 10, Magnum spec cam etc.), but if you originally intended to change only carb and intake manifold, I would suggest you to buy 750cfm carb only (like Eddy 1411 w/ electric choke) and use the suitable spacer between manifold and carb. It doesn't benefit much to change the aftermarket manifold to an old tired engine unless you rebuild the whole engine again..

Comp Cams has better selection of camshafts than Edelbrock. I use XE268H, Eddy Perf-Plus was too mild for my combo while RPM is for high-perf use.
Edelbrock's Torker plus sits in between. The sales blurb states that cam and manifolds stages (Performer, Torker and RPM) are matched however when you contact their technical department they have no hesitation suggesting mixing components up, or down one stage. eg a Torker cam and either a Performer or RPM manifold.

I've fitted a few RPM cams and they liven up whatever engine they are fitted to. Going much further however needs a matching compression ratio to get the benefit of more agressive camshaft profiles.

There are so many camshaft manufacturers with so many individual profiles that any research quickly becomes boring and meaningless. As a simple upgrade, it's far easier to pick a good brand name and choose one or two steps up from a standard cam.
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bkbridges
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Re: Best manifold and carb

Post by bkbridges »

Barefoot wrote:Taximan

I am going to do what you have done I think they will be cheaper to buy here in the states what exactly will I need a spacer kit maybe, what cam is it exactly plus should I get an air filter to fit? How easy are these to fit on my car?

Kev
Lots of choices there. I like the hydraulic roller retrofit camshafts for many reasons, cost not being one. Crane 689501 or 689511 are both good choices IF you get your compression ratio up. If not, then I would leave the stock camshaft in. With 7.6:1 compression a camshaft upgrade would most likely downgrade your driving pleasure at lower RPMs. http://www.aeroheadracing.com/chrysler-heads/" onclick="window.open(this.href);return false; has the 915 heads rebuilt with 2.08" intakes for less than 700.00 USD the pair which will make a camshaft upgrade really work!
BKB
Bruce K Bridges
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119/170
www.fbthrottlebodies.com
taximan
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Re: Best manifold and carb

Post by taximan »

Are the spacer and insulator not the same thing? phenolic something or other, a carbon fibre type material. Anyhow, as money is part of the issue here FFdave is the carb man on the forum if you want it rebuilt, the camshaft specs were beyond my mentality at the time and I kept it simple by going for Edelbrock recommended upgrade, and before I forget, I also fitted new timing chain and gears as mine was still the original plastic toothed one with a few bits missing (found in oil pickup filter)
You have to remove the chain and gears to fit the cam anyway, so makes sense.
As to heat issues, I have no insulator on a stock manifold, with a sound mechanically driven fuel pump, if I constantly had an empty carb through evaporation I would fit an electric pump, the occasional lack of fuel I do suffer results in the car taking 3 to 4 seconds longer to start, but normally after a good run then a few hours rest. Stopping for 5 minutes at a shop or to fill up is not a problem.
All this just depends how far you want to go, how much you want to spend and what you are trying to achieve, for me it was recover a few horses and make it smooth and reliable, before I made the changes my 200 bhp diesel was quicker than the Jensen, now it isn't, and that is what I was after.
Shaun.
VAUXHALL VISCOUNT 1969
MB W213 220D
MB E Class Cabriolet
JOC Member 9052
taximan
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Re: Best manifold and carb

Post by taximan »

How easy?... BATTERY OUT!... starter out....dizzy out... plugs out... you must remove belts and pulleys, water pump alternator and radiator, then crankshaft pulley(6 bolts not in a circle, fits one position only)crankshaft balance with timing marks on it will need a puller(about 15 GBP) remove the manifold and carb, then the valley pan (fit new replacement when cam done, reasonably cheap over here)take off timing cover(2 bolts underneath front edge 6 in view) remove the valve train on top of heads, and the rods (keeping in order to refit to same valves) take out old hydraulic tappets and discard,Remove timing gears and chain(need to lock engine with extension bar between starter ring gear and front edge of gearbox) withdraw cam forwards carefully (can't remember if front grille needs to be removed as may be in the way) smear new cam bearings with strawberry sauce and carefully slide back in (you don't want to scratch any bearing surface) fit new tappets after soaking in oil overnight (they come with new cam) refit valve train and rods (tricky to get them to align by yourself) and torque down.
Fit new gears and chain with No1 at TDC and timing marks aligned. Check by turning engine that all lines up again, jam/lock engine and torque timing gear bolt with thread lock, refit timing chain cover and crankshaft balance with crankshaft bolt (need big socket for it) refit pulley, valley pan and manifold(torque down evenly in order)fit new/recon carb and all ancillaries radiator etc fill with fluids. starter and battery back on.

Take your time, silly mistakes easy to make. This is a rough idea of what you are taking on.
Buy an engine book for the 440.
Shaun.
VAUXHALL VISCOUNT 1969
MB W213 220D
MB E Class Cabriolet
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mustbemad
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Re: Best manifold and carb

Post by mustbemad »

Hi Shaun,

A 1406 and standard manifold on the 7.2 have a different std/hole pattern, so the adaptor is a chunk of ali that bolts to the manifold, and then has another set of bolts for the carb. It's about 25mm thick, hence the insulator wouldn't go in as well.

Electric pump also made a big difference!

Gerard :mrgreen:
Found a III, now I know the user name is correct!
Barefoot
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Re: Best manifold and carb

Post by Barefoot »

What is the correct and best electric fuel pump I can use and where from?....thanks
taximan
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Location: Bournemouth.Dorset.

Re: Best manifold and carb

Post by taximan »

Just find one that can cope.

http://www.summitracing.com/int/parts/c ... lications/" onclick="window.open(this.href);return false;

Shaun.
VAUXHALL VISCOUNT 1969
MB W213 220D
MB E Class Cabriolet
JOC Member 9052
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