Balance Shafts / Electric Water Pump

duthehustle93

Active Member
Good morning!

I'm in a bit of an analysis paralysis situation, and would love to get input to help sway me one way or another. I'm currently rebuilding the LNF from the unfinished #05 kit I recently picked up (the engine was seized) and have it currently stripped down to the bare block. The car will be primarily a track car but I would like it to be street-able. Anything north of 300HP/TQ and I'll be happy, so my plan was a stock rebuild+a tune and call it a day, but I've got a case of the "while-I'm-in-there" and am debating a few options...

1) factory balance shafts, factory mechanical water pump
2) ZZP neutral balance shafts, factory mechanical water pump
3) OTTP balance shaft delete, electric water pump ("coolest" but the most amount of work, and I have a long way to go to finish this Goblin).

Any input (opinions or experience) is appreciated, and I have a couple specific questions...

1) Has anyone had any luck with adding an electric water pump on an LNF? I found one post on a cobalt forum, but I think there may be a better solution since there's more room in the Goblin frame. To avoid re-engineering the coolant routing, it would probably be easiest to put the electric pump-in line of the hard pipe between the WP/thermostat housing, but the turbo and exhaust manifold make packaging in that area really difficult.
2) Does anyone have experience with solid mounts + neutral shafts/balance shaft deletes? I'm curious how bad NVH is at idle w/ solid mounts and no factory balance shafts.
 

Sebnuts

Well-Known Member
I don't have the balance shaft deletes or neutral balance shafts, but you're going to need a bigger turbo and heavier valve springs so you can rev higher if you want to take advantage.
 

duthehustle93

Active Member
I don't have the balance shaft deletes or neutral balance shafts, but you're going to need a bigger turbo and heavier valve springs so you can rev higher if you want to take advantage.
Thanks for the input! That's a good way to look at it, there are much lower hanging fruit for my lower power goals. I'll just stick with option 1, get it driving as a stock LNF and can easily add more power later with turbo/valve springs/tune without needing to remove the engine again.
 

duthehustle93

Active Member
Thanks for sharing; I saw that thread but unfortunately I'm not sure how I would easily adapt that to an LNF setup (It's likely from my lack of experience in this area). It seems that they are NA or SC which leaves room to tie into the tube between the thermostat and water pump... it would be tricky to work around the TC manifold using hard lines and I'd be reluctant to use soft lines near a turbo manifold. The WP could be packaged on the intake side of the head, but it would put then switch the block/turbo feed from the "push" side of the pump to the "pull" side of the pump. I'm sure it's doable, but I was curious if there was someone with an LNF that I overlooked that has done it, and if the juice is worth the squeeze.
 

Rauq

Goblin Guru
Out of curiosity, what's your motivation for an electric water pump? I don't think anyone's had any cooling issues on a built with a fully functional cooling setup.

If it's power, as has been stated previously, there are easier ways to get more of it than an EWP and NBS.
 

duthehustle93

Active Member
Out of curiosity, what's your motivation for an electric water pump? I don't think anyone's had any cooling issues on a built with a fully functional cooling setup.

If it's power, as has been stated previously, there are easier ways to get more of it than an EWP and NBS.
The motivation for an EWP was mainly in conjunction with a BS delete.. I personally wouldn't do it with NBS's or factory BS's. The drive would be a few nice-to-have's: getting rid of the BS chain/not needing to make idlers (if doing a BS delete), a few free HP, but mainly being able to do a cooldown with the engine off would be awesome. Tracks out here in the summer are 90-110F and being able to park it and run a cooldown cycle after a session would be nice, but definitely not a necessity.

This is my first F/I build... I'm so used to the N/A mindset of focusing on the little things and small gains adding up. The idea of not doing a bunch of little things when a motor is opened up is pretty foreign to me so I appreciate the reminders of focusing on boost and a tune... seems a lot easier and cheaper. What I'm hearing is I should probably just focus on rebuilding this motor as a factory rebuild and it'll reliably meet my end power goals.
 

mike_sno

Goblin Guru
There is this shortcut of the small passenger room heat exchanger. Would it not be possible to add a electrical water pump in that loop and switch it on after the engine is switched off to circulate some water and cool it faster?
 

Rauq

Goblin Guru
For what it's worth I ran 20 minute sessions at Road Atlanta in 90° ambient temps and ECT stayed a solid 190°F. Half a lap of warmup at the beginning (which is really cooldown from heat soak) and half a lap of cooldown at the end were sufficient for me. I think people underestimate how easy it is to keep an engine cool when the block's in open air and not stuffed in an engine bay.
 

Dale E

Well-Known Member
Electric water pump can be mounted in the radiator hose at the front by the radiator/steering rack area. Close to the battery for adding a fuse/relay and dash switch if you want.
 

duthehustle93

Active Member
Thank you all for the replies. While I have a few experienced members in here, can I get a second set of eyes on my updated plan? Between this thread and forum lurking ... my plan is now a "stock+" rebuild: factory balance shafts, mechanical water pump, GM stock main+rod bearings, GM stock rings, new factory loaded head, stock oil pump, GM timing chain/guides (maybe ZZP upgraded guide??), upgraded timing chain guide bolts, GM 3 bar MAP, and a tune. Is there anything that I overlooked that I should do while I'm in here, if my end goal is reliability on circuits at ~330-350 HP/TQ on 91? The engine is an early '08 LNF with no signs of coolant/oil mixing.


There is this shortcut of the small passenger room heat exchanger. Would it not be possible to add a electrical water pump in that loop and switch it on after the engine is switched off to circulate some water and cool it faster?
Neat idea to utilize the heater core loop. If I'm not mistaken, without modifying the loop, wouldn't this loop bypass the radiator?

For what it's worth I ran 20 minute sessions at Road Atlanta in 90° ambient temps and ECT stayed a solid 190°F. Half a lap of warmup at the beginning (which is really cooldown from heat soak) and half a lap of cooldown at the end were sufficient for me. I think people underestimate how easy it is to keep an engine cool when the block's in open air and not stuffed in an engine bay.
That's definitely helpful info.. aluminum block in free air I'm sure helps as well.

Electric water pump can be mounted in the radiator hose at the front by the radiator/steering rack area. Close to the battery for adding a fuse/relay and dash switch if you want.
It'd be awesome to move weight forward as much as possible, but with the thermostat closed + pump on, would this collapse the soft line that runs the length of the Goblin on the pumps' "feed" side?
 

Gtstorey

Goblin Guru
Not sure that any pump layout is going to work to cool the engine when the thermostat is closed. I would think the temp control on the pump would be set so that doesn't cut on until the thermostat is open.

Are you replacing or reusing the stock rotating assembly. If replacing, what is the cost difference to upgrade to forged components over GM parts.
 

duthehustle93

Active Member
Not sure that any pump layout is going to work to cool the engine when the thermostat is closed. I would think the temp control on the pump would be set so that doesn't cut on until the thermostat is open.

Are you replacing or reusing the stock rotating assembly. If replacing, what is the cost difference to upgrade to forged components over GM parts.
I'm already un-sold on the EWP, but I would imagine thermostat closed + pump on would be a warmup condition. I believe you still want some coolant flow, but bypassing the radiator, so you aren't stagnating in the block and the turbo is getting coolant flow. This is just me regurgitating what I read online though.

I probably should have clarified that the rotating assembly is in excellent usable shape. So unless it's a worthwhile upgrade, I would like to use the stock rotating assembly.
 

mike_sno

Goblin Guru
My point in electric cooling is also more: I have my Garage under air. Probably the same as @Desert Sasqwatch has. If I drive the car, park it outside for a few minute and get some of the heat out of the system before I park it in the garage, that would help me with keeping my garage temperatures low. Eliminating the mechanical pump would be a nice side effect.

Regarding the coolant loop. I have not seen a full coolant diagram, but the heat exchanger loop should be open all the times independent of the thermostat or??
 

Gtstorey

Goblin Guru
My remarks are in regard to keeping the engine cool, the main purpose of a cars cooling system. The purpose isn’t to keep the coolant cool.
 

Desert Sasqwatch

Goblin Guru
My point in electric cooling is also more: I have my Garage under air. Probably the same as @Desert Sasqwatch has. If I drive the car, park it outside for a few minute and get some of the heat out of the system before I park it in the garage, that would help me with keeping my garage temperatures low. Eliminating the mechanical pump would be a nice side effect.

Regarding the coolant loop. I have not seen a full coolant diagram, but the heat exchanger loop should be open all the times independent of the thermostat or??
I wish I had A/C in my garage! Just well insulated to help keep the heat out in the summer and the heat in during our winters. Not that I haven't thought about it tho...
 
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