Hood Clearance issue?

Dropped the engine in today. Engine mounts are all bolted solid. Engine seems to be sitting a bit high. I need to add in the 1/2" crossmember spacers still, that will allow the bell housing to line up I think. But it seems to me that the throttle body is more than 2" too high. Did I install something wrong? I don't think the engine can get any closer to the cross member.

This is an LS6 intake with 3 bolt to 4 bolt TB plate, and a truck DBW throttle body. Maybe the car TBs are different?

Ignore the fuel crossover line, that will be fixed. Cheap ebay one that it came with is too long.
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I had the same issue. Also using the truck DBW TB. Solved it by flipping it over. I had to do a tiny bit of grinding on the tb servo housing and on the water pump to get it to fit but it wasn't difficult.

Ok, great, simple enough. I'll do that.

I put the 1/2" spacers in now. Still can't get the bell housing to align. Seems like the torque tube is hitting something before it lifts up high enough. All the exhaust brackets are still on it, so maybe it's one of those.

majormojo wrote:I had the same issue. Also using the truck DBW TB. Solved it by flipping it over. I had to do a tiny bit of grinding on the tb servo housing and on the water pump to get it to fit but it wasn't difficult.

Do you have any pictures of the throttle body?

Looks like the casting around the stepper motor in mine touches even the water pump pulley. So I don't think flipping it will work for me... I might have to buy a car TB. It would be nice to have a 90* right out of the intake before the TB.

This is the only pic I have after flipping the TB. I can take a closer photo if it would be helpful. I'm using a truck motor with OE water pump.

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Ah, the different intake and water pump must be what allow the clearance in your case. Is that an LS3 intake?

I have an LS6 intake and GTO water pump. I'm planning to get an LS3 Throttle body, then I shouldn't have issues.

Yes that's right, I'm using an LS3 intake.

superman22x wrote:Ah, the different intake and water pump must be what allow the clearance in your case. Is that an LS3 intake?

I have an LS6 intake and GTO water pump. I'm planning to get an LS3 Throttle body, then I shouldn't have issues.

Does the LS3 use a 3 bolt or 4 bolt throttle body? I know one of the generational differences in the intake to throttle body connection was a change from the early 3 bolt pattern (LS1/LS6/early trucks) to a 4 bolt pattern for later versions. The two combinations cannot be mixed and matched.

Also if the truck DBW throttle body is too tall, then I may end up needing to replace both my computer and throttle body with parts designed to be used with the cable throttle. Unless GM perhaps made a low profile DBW 3 bolt throttle body that is also compatible with my pedal module and ECU. That said, until the engine and related parts are sitting in the car, I'm not going to worry about it.

LS3 is a gen IV intake, and all gen IV TBs are 4 bolt. LS6 is a 3 bolt, and smaller diameter. All Gen III TBs are 3 bolt. I have an aluminum adapter plate to go from a 4 bolt TB to a 3 bolt manifold.

What ECM are you running? If it's a gen IV engine, you can't run a DBC TB as far as I know. The LS3 gen IV DBW TB has the motor on the side instead of the top, so it should work better. I'll post a picture tonight when I pick it up.

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LS3 DBW TB[You must be registered and logged in to see this image.]

Soperman, I didn't realize you had an adapter.

Both my intake and TB are three bolt, and my TB is DBW, as are my ECU and PCM. Unfortunately my ECM is not one that can be changed from DBW to cable; I've opened it up and checked for the appropriate chip. Like I said, at this point I'll sort it all out once I've got the engine sitting in the car.

Oh, ok. You are using a Gen 3 controller then? The early DBW throttle body might fit different than mine.

As an additional update, that is related. I removed the reservoir from my power steering pump, and put in a 1/4" NPT Bung. I actually just JBWelded this in place, since I didn't want to weld on the pump. My plan is to run a NPT to hose barb fitting from here to the stock 944 PS reservoir (my car will not see any track time). This allows more clearance in front of the head to run the intake piping over to the driver's side fender. If you were using the vehicle for anything else, you might want a bigger reservoir. Otherwise, I think this should work ok. Thoughts?