[GoreMaker]

Is it possible to lower the engine by modifying the mounts? Or does someone make engine-lowering mounts? Even just 1/4" would be helpful. This is a 1977 Trans Am with Pontiac 400

[Joe's Garage]

Your steering linkage is pretty close to the oil pan with the engine in the stock location.

[25stevem]

Are you running headers?
If so how close are they to the frame?
There is not much play to do such anywhere but to slot the bolt holes where the mounts attach to the block and slot our those holes by like 1/8”.
Even then you might need to find reduced head size bolts like a Allen head instead of a Hex head.

Note that you can’t lower the mounting brackets that attach to the frame because that will tighten up the Vee.

[GoreMaker]

Nope, no tube headers, just cast RARE headers. I'm just trying to find some room to accommodate a slightly taller intake manifold without running a drop base air cleaner. I figured with a thinner carb gasket, a slight engine drop and some minor machining on the intake manifold, that might be enough

[78w72]

what intake are you wanting to use? depending on engine power level, there are plenty of stock height intakes that will run almost as good or better than some high rise intakes.

[25stevem]

You could sneak in like .060” more clearance by placing a washer on every hing to hood bolt and then raising up the two front hood bumpers and then slotting out the hood latch system bolts by that same .060”.
I know it’s not much but little things here and there add up.

[GoreMaker]

Originally Posted by 78w72

what intake are you wanting to use? depending on engine power level, there are plenty of stock height intakes that will run almost as good or better than some high rise intakes.

What stock-height intake manifolds with a spreadbore are available other than stock cast-iron or the much-maligned Edelbrock Performer?

What I have on hand are both of the above and a Crosswind (which is about 1" taller than stock). I like the layout and weight of the Crosswind better, so that's what I'm planning to use. But I'm trying to bring the air cleaner down about 3/4" or so to accommodate it.

[promptcritical]

Street Dominator? For some reason I’m thinking they fit under the hood. Ram Air and HO stock manifolds are aluminum.

[78w72]

Originally Posted by GoreMaker

What stock-height intake manifolds with a spreadbore are available other than stock cast-iron or the much-maligned Edelbrock Performer?

What I have on hand are both of the above and a Crosswind (which is about 1" taller than stock). I like the layout and weight of the Crosswind better, so that's what I'm planning to use. But I'm trying to bring the air cleaner down about 3/4" or so to accommodate it.

holley street dominator. tomahawk (or current name). HO/RA4.

depending on power levels, the factory iron or HO intakes will perform as good or better than the crosswind & are much easier to use the factory linkage & choke setups. & when max ported a factory intake can support up to 600hp, lesser basic porting & gasket matching will easily support 400-450.

just a suggestion to use a lower rise intake & avoid a lot of extra work & possible clearance hassles lowering the engine.

[GoreMaker]

Originally Posted by promptcritical

Street Dominator? For some reason I’m thinking they fit under the hood. Ram Air and HO stock manifolds are aluminum.

Oohh that's a nice one, too. Not sure I wanna spend the money on yet another intake manifold, though.

Conundrums, conundrums...

[promptcritical]

Stock manifolds are really good. Iron and aluminum. My 455 made over 500HP with a Pontiac HO manifold and a SD service replacement Q-jet.

[GoreMaker]

Originally Posted by promptcritical

Stock manifolds are really good. Iron and aluminum. My 455 made over 500HP with a Pontiac HO manifold and a SD service replacement Q-jet.

I have no doubt about that, but my main concern is weight, and there's no way I'm getting my hands on a stock aluminum intake manifold. I've been trimming weight up front bit by bit, and an aluminum intake manifold saves over 30 pounds at the highest point of the engine. So far I've managed to eliminate 142 pounds from the front, and the aluminum intake accounts for over 20% of that.

[78w72]

Originally Posted by GoreMaker

I have no doubt about that, but my main concern is weight, and there's no way I'm getting my hands on a stock aluminum intake manifold. I've been trimming weight up front bit by bit, and an aluminum intake manifold saves over 30 pounds at the highest point of the engine. So far I've managed to eliminate 142 pounds from the front, and the aluminum intake accounts for over 20% of that.

im sure you know, but they do make repros of the HO/RA intakes for decent prices.

weight saving is nice, but at what cost? i changed my SD ported cast iron intake for a SD ported HO alum intake... didnt gain any noticeable speed or ET.

what power level are you at & what engine do you have? for smaller 350-400s not making or needing max power, a performer will work perfectly fine for the street & not require lowering the engine or drop base air cleaners. i ran a performer on a mild 455 in a 78 t/a back in the 90's, it didnt have any of the bogging or other negative symptoms some have reported for the performer on a larger cid engine, im sure it was hurting some HP, but was never noticed for a street car that was driven & abused daily.

again, just some suggestions without knowing engine specifics to make life a little easier.

[jhein]

Originally Posted by GoreMaker

I have no doubt about that, but my main concern is weight, and there's no way I'm getting my hands on a stock aluminum intake manifold. I've been trimming weight up front bit by bit, and an aluminum intake manifold saves over 30 pounds at the highest point of the engine. So far I've managed to eliminate 142 pounds from the front, and the aluminum intake accounts for over 20% of that.

What is the concern about weight? This is in the street section so I'll assume you're not trying to shave off hundredths at the track. For just 28 pounds, trying to lower the motor seems like its not worth it, unless maybe you are racing. Seems like you'd be better off with a proper height AL intake and porting it.

Or, you could just go on a diet.

[GoreMaker]

The motor is already out, this isn't a hardship. I'm just checking into alternatives that I didn't have info on before. This thread is providing a wealth of information. 30 pounds at the top of the engine makes a very noticeable difference in autocrossing

[25stevem]

To me you should go with a repro Aluminum RAIV / 455 HO intake and if you have not done so open up the rear of your scoop.

In fact if your good with body work you should extend the snout of the scoop closer towards the windshield, every 1/2” helps!
You will need to port match these repro intakes to your heads if they are at standard D port size.

The plus of this is that above 50 mph the pressure of the open scoop overcomes the too small stock air filter for something like a 500 hp motor and the slight reduction in runner and Plenum depth that these repro intakes have.

[GoreMaker]

Originally Posted by 25stevem

To me you should go with a repro Aluminum RAIV / 455 HO intake and if you have not done so open up the rear of your scoop.

I think you're right. That's what I ended up doing. The shaker scoop is in fact open.