4 bolt mains

[ForcedFirebird]

I am not aware of anyone having an issue after the lower intake has been flipped around. I never thought about the coolant flow with the head blocked off at the back now, but I will be doing this in an MGB swap. I would hate to have to setup a long hose to the back, but it could be done.

HMMM. Have to wonder how good the cooling is in the back of the block when the water pump would only be really circulating the water at the front in a RWD situation.

The 5&6 would be even worse in this case, even with the squirters on the 3500 block. Now I wonder if it is wiser to get circulation elsewhere if the manifold is turned around. Even though we have not heard of any problems, ahs any RWD with FWD heads been examined after abuse?

[Joseph Upson]

HMMM. Have to wonder how good the cooling is in the back of the block when the water pump would only be really circulating the water at the front in a RWD situation.

The 5&6 would be even worse in this case, even with the squirters on the 3500 block. Now I wonder if it is wiser to get circulation elsewhere if the manifold is turned around. Even though we have not heard of any problems, ahs any RWD with FWD heads been examined after abuse?

This issue is addressed in the 3900 and 3500 VVT engines in which case the cooling efficiency would not be optimum with the intake turned around on the non VVT 3500. The cylinder heads on the VVT engines have assymetrical coolant holes as in the front half of the head deck surface does not mirror the rear half resulting in left and right cylinder heads for these engines.

Unfortunately a cylinder head shot is the one picture I do not have to show you the difference as I did not notice it right away when I disassemled the engine. The good news is if the VVT engine's cylinder head valves will clear the 3500 bore you can have the coolant exit the front of the engine with proper cooling characteristics as long as you matched the coolant holes in the OE gasket and make outlet fittings for the heads. You will also have upgraded your intake system flow characteristics considerably as well more so for a blown engine.

[Superdave]

HMMM. Have to wonder how good the cooling is in the back of the block when the water pump would only be really circulating the water at the front in a RWD situation.

The 5&6 would be even worse in this case, even with the squirters on the 3500 block. Now I wonder if it is wiser to get circulation elsewhere if the manifold is turned around. Even though we have not heard of any problems, ahs any RWD with FWD heads been examined after abuse?

not to get too far off topic but i noticed the other day that it dosen't look like you can drill a 3500 block on the opposite side for a RWD starter.. do you still have a lx9 block sitting around to verify?

I could be wrong though...

[Joseph Upson]

Another note about the fwd main caps, 1,2 and 3 for the 3500 and 3900 are powder metal and 4 is cast iron. I hope I'm right in saying this but my interpretation is that the powder metal caps are stronger than the cast iron caps. The 3400 has the same combination except I'm not sure when this switch was made so all may not have that change, 2004 does.

[MidnightriderZ24]

doesnt rodney dickman sell a kit to drill 60* v6 blocks for a rwd trans? found it, you just need to click the tools section, its under 3.4 drill jig :

http://www.rodneydickman.com/retail_new.html

[Wiz85]

Well guys here's some pics I took today to show the problems. You can click on the picture.

First pic shows the intake like it is factory and how the WP passages protrude up, and the second pic show what happens when I reverse the LIM.



And here's a pic of the LIM flipped over and the thermostat housing is on the left (rear of head). Notice that there's only a coolant passage through the intake only at the rear near the thermostat and blocked off at the front. That's what's getting me worried about chevette_boy's turbo setup since it looks like he's using a backwards intake. If there were intakes on other 3x00s that have both passages front and rear I would us it with a RWD WP setup setup. Probably what I'm going to do is weld on a 1 3/4" Al oval pipe to the thermostat and run it under the UIM to the front.Now as for my 3rd problem about belt routing, like I said I machined a pulley last weekend and put it to the right of the WP. As seen here, hope it works.


Also Superdave, here's a pic of the passenger side block on my 3100, it's not flat at all to mount a starter. The best option I can think of doing for a RWD trans swap is using a 2.2 L Chevy bellhousing to a T5 b/c the IronDukes had a driver's side starter and the bellhousing pattern is the same.

[Joseph Upson]

Actually it would be better if you just whipped up a piece of flat iron and weld it to the corner to complete the mount pad then drill and tap it. The RWD 3.4L poses the same problem in the Fiero swap at least the engine I had did, where the corner of the opposite starter mount pad was angled at the end. I didn't even bother welding on the block. I just drilled the inboard hole, ground a flat spot in the angled area so that I could drill into it, then mounted the starter head on the block and used the outboard bolt passage to center and target the drill bit. I was careful not to over torque the outboard bolt since that area of the starter had no compression surface. I never had a problem with it. I used the actual starter nose as a jig after removing it from the starter assembly.

[Joseph Upson]

I don't believe you'll have a problem with the manifold being reversed after giving it some thought. The water is still being forced into the block and up into the cylinder head and then towards the exit. It will rearrange the thermal character as far as heat distribution but there is nothing keeping the coolant at the rear of the cylinder head from flowing forward as the water exits the intake outlet. You could use a cooler thermostat for added piece of mind or remove it all together to increase overall flow through the system. More convincingly the twin turbo chevette has had main cap problems instead of head gasket and overheat problems.

[geoffinbc]

Well the head gaskets should have water passage holes that direct water flow. They could be moved around depending on application.

In a RWD vehicle you want water to come in the front of the block and head to the back of the block and then up to the head and out the intake.

[ForcedFirebird]

Well after looking at pics of the various engines I have dissasembled, it appears that there may be a problem with cooling reversing the intake manifold.

The 3x00 intakes have the crossover coolant passages that tranfer the coolant from one sid of the block to the other are closest to the coolant neck. The other two are sealed off. When turing the intake 180*, the waterpump will be forcing coolant in the block, up to the passage, over to the other side of the block and back out the water pump. In a FWD configuration, the coolant neck is furthest away from the water pump meaning the coolant would be forced to the back of the block before crossing over, if that makes sense. Here's pics of the 3500 and 3400 intakes...



What wiz is saying makes total sense, what's going to cool #5 and #6 cyls? I now need to see if I have room to do what you are saying, Ben.

wiz, it's easy with a grinder to make the RWD cover fit the coolant neck from a 3x00...

[geoffinbc]

Uhhh I think you have your water flow mixed up. Coolant does not go from one side to the other. If comes into the pump from the lower rad hose and the heater hose (if the t-stat is open) it then is forced into the block through the holes in the front. The water flows to the back of the block and the up into the heads and out the 2 passages you see in the intake manifold where it meets at the thermostat housing and into the upper rad hose, there is also the alternate path through the heater hose to the heater core. This is why the head gasket water passage holes are different and have directions on what way they face. The holes in the water passages are key to make water flow the right way.

[ForcedFirebird]

Uhhh I think you have your water flow mixed up. Coolant does not go from one side to the other. If comes into the pump from the lower rad hose and the heater hose (if the t-stat is open) it then is forced into the block through the holes in the front. The water flows to the back of the block and the up into the heads and out the 2 passages you see in the intake manifold where it meets at the thermostat housing and into the upper rad hose, there is also the alternate path through the heater hose to the heater core. This is why the head gasket water passage holes are different and have directions on what way they face. The holes in the water passages are key to make water flow the right way.

Not confused. Whats going to get coolant to the back of the heads with the manifolds in the pics? The 3x00 intake has the 2 water ports furthest from the t-stat blocked off. The entire back of the engine is going to get less flow.

This means the coolant is going to stay in the front of the block in a RWD configuration, correct? It's not going to circulate properly.

[Wiz85]

I can understand that there's coolant passages at both ends of the heads so that you can swap heads from side to side, but why isn't there a passage at the front of the LIM? I guess I would be answering my own question by saying that I think it's b/c by blocking it off, any coolant entered at the front of the head from the block would be forced to run across the head and then into the intake and thermostat. Pretty much coolant can enter anywhere into the head from the block passages (front, middle, rear) and then across the head towards the back. It's like the block are the arteries and the head are the veins, b/c blood can flow in different paths but long it get from point A to B. But I wonder if by blocking the rear passage, there would be some stagnate coolant at the back, but lots of flow in the front of the head. I know I'm the one that's started the off topic but it's been bothering me. Plus, how are the RWD block, heads, and intakes designed for coolant passages. I probably should just sleep on it.

[Wiz85]

The thing is ForcedFirebird, to save money as well as space in my chevette, I want to take advance of the crank pulley/damper by moving the engine back and down clearing the sway bar. Wouldn't be able to with the RWD front setup, plus to change over to that setup is going to cost money I need for other stuff.

[Ortie666]

The thing is ForcedFirebird, to save money as well as space in my chevette, I want to take advance of the crank pulley/damper by moving the engine back and down clearing the sway bar. Wouldn't be able to with the RWD front setup, plus to change over to that setup is going to cost money I need for other stuff.

hahaha, Like a big fat bottle of nitrous.. Do the custom intake, they actualy work pretty good, being how I was told many times that it would never work.. If you want Pm me and Ill give you info on the port opening size for powerband range, ive already played around making a couple of those aluminum intakes fitting 4bbls, and if the port openings are to wide ur powerband goes threw the roof.. (Not good for street use)