Plans for L32/3X00 Hybrid

[tkoforpresident]

Where does the rest of that tube go to? If it goes to the heater core it leads to the firewall, at the rear of the engine bay, possibly on the passenger side. It's safe to run a decent run of rubber reinforced heater hose if you have to, as long as it's secured and not stretched tight so the drivetrain doesn't rip it loose.

yeah it does go to the heater core which is on the passenger side in the rear but the rubber hose turns into a metal line by then. I suppose i could always cut that tube and then attach a short stretch of hose from there to the outlet on the LIM...

just seems odd that in all the threads I have read about this swap nobody has once mentioned this modification which is indeed a pretty prominent one.

[TechRod]

Would it be possible to remove the tube and tap the hole for a fitting?

[tkoforpresident]

if it is possible i wouldn't know how to do it lol

[TechRod]

Tapping a hole isn't very difficult, but can be tricky the first time. I'm sure a friendly machine shop would do it rather cheaply.

[tkoforpresident]

or perhaps I could just use a hose clamp?

[TechRod]

I'm sure someone with some hands-on experience will log in soon and shed some light on this for both of us.
I'm planning a similar top swap on my 3.4L Chevette (at least another year away) and that tube will actually work out great for my engine bay.
I'll be keeping my eyes peeled on your build

[CNCguy]

Max... There is a rubber hose connecting the metal tube to the heater core. You should be able to remove that and run a rubber hose from the heater core to the LIM. If clearance is tight you could find a preformed hose.

[bszopi]

That metal line is just press fit into the manifold, so if you wanted to go with the fitting route, it could be done. But, I'd look into Marc's suggestion first.

[tkoforpresident]

sounds good guys. Thanks

[tkoforpresident]

Good news, I just looked at my Haynes manual (since my car is buried under 4 feet of snow) and the heater core hose is only connected by one of those crappy spring clamps at the heater core. This means I should be able to take it off, get a few feet of matching hose size and run it down to the LIM outlet in the back. Not only will this look cleaner than the current setup but should also get rid of some unwanted piping up front. Unless the bend is more prominent than I can perceive from looking at pictures (and my memory) I don't think it will bend in an undesirable manner.

[pocket-rocket]

Max... There is a rubber hose connecting the metal tube to the heater core. You should be able to remove that and run a rubber hose from the heater core to the LIM. If clearance is tight you could find a preformed hose.

I was going to say, I couldn't see GM throwing a 3-4 foot metal line on the end of the heater core, lol. It's like that metal line that runs along the passenger side wheel well in the W's.

[ForcedFirebird]

You will end up with an extra heater core hose on your engine since there's one on the water pump for the 3.4, and in two places on the FWD manifolds.

Throttle cable can be pirated from a GM truck and is a direct fit (have part number at shop).

The TB sensors are a direct swap, they are the same.

The t-stat needs to be the FWD unit.

You can boost the 11.5:1 SCR motor, just be aware that the tuning has to be spot on.

Pacesetters work, you just need to slot the top holes of the flanges and the roofs will match the headers just fine, the 1.5" primaries being round will just barely interrupt the "square" corners on the bottom of the "D" shaped exhaust ports of the FWD heads. GM raised the roofs, the bottom mounting holes stayed in the same location.

[tkoforpresident]

You will end up with an extra heater core hose on your engine since there's one on the water pump for the 3.4, and in two places on the FWD manifolds.

Throttle cable can be pirated from a GM truck and is a direct fit (have part number at shop).

The TB sensors are a direct swap, they are the same.

The t-stat needs to be the FWD unit.

You can boost the 11.5:1 SCR motor, just be aware that the tuning has to be spot on.

Pacesetters work, you just need to slot the top holes of the flanges and the roofs will match the headers just fine, the 1.5" primaries being round will just barely interrupt the "square" corners on the bottom of the "D" shaped exhaust ports of the FWD heads. GM raised the roofs, the bottom mounting holes stayed in the same location.

John if you could get me that throttle cable part # I would be very appreciative. It would save me a lot of trouble.

Also, I'm not entirely sure I understand what you mean by my having "an extra heater core hose"

[tkoforpresident]

now that I think about it the hose that I highlighted in RED earlier is the one going to the water pump so that can't be altered at all.

It's the hose NEXT to it that would normally run into the 3.4 LIM that I will have to alter since there is no fitting for it on the 3500 LIM

is this correct?

If that's so then there shouldn't be a problem. I will just route the one hose normally to the waterpump and the other one (the one that used to go into the 3.4 LIM) to the NEW outlet coming out of the rear of the 3500 LIM

I think that makes sense...

[tkoforpresident]

NO but seriously, I'm freaking out. What does John mean by 2 heater core outlets on the FWD manifolds?

The only one that I saw was that metal tube that exits at the rear pass. side.

I need to figure out how to run these hoses

I have got to be correct though about the heater core hose running to the water pump... and that it should not under any condition be removed.