Big Block Tilting Toward Firewall

[Sixball]

I posted this in the 88-98 Section, but this isn't really year specific, so I thought I'd post here as well. I took the SBC 350 out of my 94 1/2 Ton Sierra and dropped in a 1970's BBC 454

I noticed when installing a Dual Quad tunnel Ram, that my engine tilts toward the Firewall - the carbs will not be level at all. I haven't been under the Truck in a while to check the pinion angle, but I need the engine to tilt forward quite a bit to get the engine level. I used the original motor mounts (Small Block) when I installed the 454. I believe those are taller? I had a hard time finding a Tranny mount for the Turbo 400, I remember going back to the Parts Counter several times.

Will changing the SBC motor Mounts to BBC Motor Mounts tilt this forward? Or do I just need a different Tranny mount? I just noticed this last night and haven't had a chance to crawl under the Truck. Brainstorming ideas as to how this happened and how I can correct it.

[geezer#99]

Whose tunnel ram are you using?
Post a pic of it.

[kwmech]

Yeah, pics. None of my big blocks sit in the engine bay level, they all tilt back a little bit

[Sixball]

Originally Posted by kwmech

Yeah, pics. None of my big blocks sit in the engine bay level, they all tilt back a little bit

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[Sixball]

Originally Posted by Sixball

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I hope the picture shows up. Never-mind the mess, I’m still working on some Body Work
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[geezer#99]

That doesn’t look to bad.
I assume you hope to run an edelbrock carb or cut a notch in the firewall.
Also assume your trans is a turbo 400.
You can buy wedge spacers to level the carbs.

[kwmech]

Engine looks too far back in the compartment. Where are the engine mounts bolted to the frame

[Sixball]

Originally Posted by geezer#99

That doesn’t look to bad.
I assume you hope to run an edelbrock carb or cut a notch in the firewall.
Also assume your trans is a turbo 400.
You can buy wedge spacers to level the carbs.

I’ll be running 2 Demon’s. I have an Edelbrock on hand, it took up the same amount of room.
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[Sixball]

Originally Posted by kwmech

Engine looks too far back in the compartment. Where are the engine mounts bolted to the frame

Plenty of room with the old HEI mounted before the firewall. The SBC Motor Mounts are in the same location as when the 350 was in I believe (swapped it 3 years ago, can’t remember). Turbo 400 with the stock 94 Crossmember moved all the way forward.

It looks like if the Motor could tilt about an inch forward, I wouldn’t need to notch the Cowl / Windshield Wiper area. Is it achievable to get a 1 inch tilt?
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[geezer#99]

Lift the tailshaft up and see how much room you have.

[kwmech]

Small block stands should be in the front hole set. If memory serves some of the t400 big blocks had 2 3/8'' steel plates spacing up the trans at the mount

[mongocanfly]

Dont most intakes have a angled carb mounting surface?..something like 3deg or so towards the front

[Sixball]

Originally Posted by geezer#99

Lift the tailshaft up and see how much room you have.

Will I be able to loosen the motor mounts and lift the tailshaft that way? I’ve never had this problem before, just pull and drops in the past.
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[geezer#99]

Don’t need to loosen the mounts. They flex a bit.

[geezer#99]

Originally Posted by mongocanfly

Dont most intakes have a angled carb mounting surface?..something like 3deg or so towards the front

If you look closely you’ll see the rear carb mount is slightly taller than the front of the front carb mount.

[Sixball]

Originally Posted by geezer#99

If you look closely you’ll see the rear carb mount is slightly taller than the front of the front carb mount.

Yes, it’s built in, hard to tell from picture, but I still need an inch or so to tilt it forward.
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[geezer#99]

Here’s some wedge spacers.



https://www.summitracing.com/search/...r-wedge-plates

[Sixball]

Thanks. The issue I am having is not as much the angle of the carbs, but the ability to get some nuts on the studs, when the carb is able to drop onto the studs. Here is a closer picture

[mattfranklin]

Wow, that's tight. I wonder if other guys with a BBC tunnel ram setup have had to notch the firewall at all.

[Sixball]

Originally Posted by mattfranklin

Wow, that's tight. I wonder if other guys with a BBC tunnel ram setup have had to notch the firewall at all.

I have a Weiand Tunnel Ram on hand that is about 3 inches shorter than the Edelbrock. I am going to mock it up and attempt to adjust my TH400 to see if I can get a bit more level - which will move the carb mounting a bit more forward at the same time.

[Sixball]

Problem solved. The Vintage Edelbrock Intake was a lot taller. I liked the Polished look, but I had to switch to my natural finish Weiand. This is just a mock up. I still need to tighten everything down and install the correct Tranny support to tilt the engine forward a bit

[geezer#99]

I can hear it bog and it’s not even running yet!
It’ll take a bunch of tuning to run right.

[Sixball]

I didn’t have any issues tuning the Tunnel Ram with 2 Holley 450’s on an SBC in my 72 C10. I build fuel induction components for Harley’s. I’m no stranger to tuning.