[mixwell]

It's 85 where I'm at and still waiting on AC bracketry.

Ha


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[BottledFedMR2]

It's 85 where I'm at and still waiting on AC bracketry.

Ha


Sent from my iPhone using Tapatalk

A lot of people are but there are several projects going on. Now that this appears to be resolved we can get on this again. We still cannot properly test the A/C stuff until we get warmer weather. At 30 out you can't tell if it's working or not. Usually we have warmer weather by now.

 

[BottledFedMR2]

WHOOO HOOOO! We got heat so hot you can't even leave your hand in front of the heater at idle!!! So it's been in the mid 30's here lately, so we haven't been able to much testing but we will as soon as the temps rise. But as of right now were are seeing better results than ever. Car's idling at 160 which is better than the 2zz.

UPDATE: We believe that with stock internals of a K20/24 in a MR2, the OEM water pump is at the maximum performance due to increased friction coolant length and overall resistance. If you modify the internals and start to push the horsepower, you will exceed the capabilities of the OEM water pump, seen on 4 highly modified vehicles at this point. We have not seen a successful highly modified car running a rear engine front mounted rad and only a OEM pump. We have also reviewed multiple front mounted radiator and rear mounted engine build's (3) in various other models who all ended up experiencing the same issues we had and who's issues were resolved with the addition of a electric water pump. Our reasoning here is that EVERYONE we talk to with stock setup's seems to not have any issues with cooling but as soon and you start to modify it, you have over heating issues that vary greatly with respect to symptoms that may be dependent on the decrease of modification ( IE more HP more heat= more problems). We can only speculate that with higher HP comes increased engine temp's and the OEM pump starts to cavitate just enough that it cannot exchange the increase in temps with the coolant. We have install the Stewart EMP electric pump in one car. (it's inline and same size as stock pipe's so it nearly drop's right in as opposed to other K kits's) using two OEM hoses, 1x 90 degree 1.25 inch hose and custom mounts and have been unable to reach cylinder engine temps higher that 170 with a mishimoto thermostat and OEM pump running. We have beaten the car in 60 degree weather without taking it below 5000 rpms and have consistently kept heat through the vents and not over heated the engine or developed air pockets. The fans have been set to 190 and only kick on at idle. We have been running the car daily for the past 4 days without any issues. We will be doing the same modification to the second car this weekend which we are hoping to hit over 300 whp on.

 

[liberty mkiii]

Brandon Wilbur with the 1000+ hp sw20 kswap mr2 told me that he also had cooling issues (no suprise there) and that implimenting a swirl pot at the coolant port right out of the cylinder head made a massive difference.
With that said he never runs it for more than 15 seconds at a time...

He has now swapped his setup into an NSX.

 

[TheMidasTouch]

That's exciting Brandon! Do you have any pics?


Also, went on a trip to Japan. Came back to this.

"Friends"

 

[BottledFedMR2]

That's exciting Brandon! Do you have any pics?

Yea I'll post up some pictures in a couple day's. I plan on taking some "step by step" picture's during the second install and posting them all up.
Part's needed are:

EMP Stewart electric water pump - Summit Racing/Jegs - # EMP-E389A-BK14 @ 399.97
1 pc - # 16572-22040 - r/h oem front rad hose
1 pc - # 16571-22040 - l/h oem front rad hose
1 pc - Samco 1 1/4 inch I.D. 90 degree bend hose - minimum 4 inch long legs
1 pc - JEGS 3 inch long x 1 1/4 inch o.d. rad hose connector - # 511170 @ 9.99
6 pc- 2 inch hose clamps

You'll also need some 12 gauge wire, a 20A switch, 60A relay and a fuse box. This is wired up to a relay and a switch on the dash. If you don't the pump will quickly eat your battery away. Also if you run the pump before starting you can trip a "daughter motherboard code" due to the drop in voltage.

 

[BottledFedMR2]

Brandon Wilbur with the 1000+ hp sw20 kswap mr2 told me that he also had cooling issues (no suprise there) and that implimenting a swirl pot at the coolant port right out of the cylinder head made a massive difference.
With that said he never runs it for more than 15 seconds at a time...

He has now swapped his setup into an NSX.

Yes we made some other modification like this as well. I'm 100% sure that the pump is the most effective part. If he gets the flow up to 100 GPA he should be able to run it for longer. I was reading that the new Bugatti has two electric pump's flowing at over 200 GPM for 1600 HP

 

[TheMidasTouch]

Which hose did you put this in? Radiator to hardline up front? Lower Engine coolant hose?

 

[BottledFedMR2]

Which hose did you put this in? Radiator to hardline up front? Lower Engine coolant hose?

Pump is 7 inches long and 4 inches wide. Fits perfectly in the coolant in hose, going to the rad (driver side). Between the rad and the steering rack. This way you can mount it to the frame rail. Takes about an hour to install and 30 minutes to bleed

 

[TheMidasTouch]

This is something I put together for another thread, but I thought it could be useful here:

I really can't speak to the Toyota engines. But I have built and tuned quite a few K series over the years.

As such, I have seen the following N/A outputs as typical norms and observed maximums on DynoJet dyno's with SAE correction. Assuming the usual suspects required to get these engines running. This includes a decent header [R-Crew, DTR, some big-tube longer primary], 3" exhaust, RBC style intake manifold, ~18"-20" long 3" diameter intake.

K20(A2,Z1,Z3, etc..)All OEM from oil pan to valve cover with usual swap periphery (Header, RBC intake manifold, 3"-3.5" intake, OEM style TB)
Norm: 225 whp | 160lb/ft
Max: 241 whp | 170lb/ft

K24A2 OEM as above
Norm: 230whp | 185lb/ft
Max: 258whp | 195lb/ft

K24(A1,A3, etc..) OEM as above
Norm: 210whp | 180lb/ft
Max: 219whp | 185lb/ft

K20A3
Norm: 160whp | 155lb/ft
Max: 201whp | 160lb/ft

Now we start adding cams and head work to OEM bottom ends with tuned periphery
K20(A2,Z1, etc..)
Norm: 245whp | 170lb/ft
Max: 264whp | 172lb/ft

K24A2 I understand some folks have gone mid 10's on OEM bottom K24's.
Norm: 250whp | 195lb/ft
Max: 301whp | 203lb/ft

Then when we open up the engines to Full N/A builds results can be largely grouped into Bore x Stroke in millimeters as the engine code becomes largely arbitrary. You usually have three strokes to play with: 86mm (as found in the k20), 99mm (as found in the K24), and 102 (aftermarket crank). More are available, but these are the usual suspects with 99mm being the standard and 102mm being largely applied to the competition guys.

86-87 x 86 *this is an unusual build approach so my data is limited. Most opt for at least the 99mm crank.
Norm: 265whp | 180lb/ft
Max: 320whp | 185lb/ft

87-90 x 99 This is by far the most usual N/A build. A slight overbore with 12.5:1 - 15:1 compression. Cartel 3.5-5.5's cams, Skunk2 Stage 3 Cams, or some equivalent. Some have head work done, some don't. Usually rev to 9.5k sometimes 11-12k. Custom header, 3"+ exhaust or hood exit competition header. Tuned/ported intake manifold and intake piping or ITB's. Current All Motor Street record is 9.701 @ 142.37 (WCF 2014).
Norm: 305whp | 210lb/ft
Max: 405whp | 225lb/ft

89-91 x 102 Usually competition builds. These guys are very rarely running street fuel and typically run a blend of race fuels E98 and may or may not even run alternators. Occasionally run in street cars, but you really need a solid fuel foundation to get into the big numbers and almost invariably rev the first couple gears to five digits at least. Current All Motor Pro record is 8.92x @ 152.xx (WCF 2012).
Norm: 340whp | 220lb/ft
Max: 482whp | 235lb/ft * Some of the current All Motor Pro guys have indicated they are eclipsing the 500whp!!! mark, but this is my personal observation.

Here are a few nice resources/citations:
All Motor Records - Honda Tech
K24a2's Stock Block - K20a.org
Dyno Chart Registry - K20a.org

 

[TheMidasTouch]

So Brandon/Dave/All,

I've had another thought regarding the cooling issues that could be worth some conversation. My car is up and running (yay!) and it feels great having traction in first gear. :biggrin:

My fans are on, my system bled, my radiator working wonderfully. With fans on: nearly room temperature air on the cold side, very hot air on the warm side, coolant pipes similar.

However, when idling for long periods of time, temperatures slowly creep toward dangerous ranges (206-208).

So, what can this mean?

It resolves to two possibilities for me.

A ) Coolant simply isn't moving fast enough at idle.

B ) Too much hot coolant is being re-introduced back into the engine, and not enough cold coolant drawn through the radiator.

With Brandons aux water pump, I think we solve both possibilities.

However, I had a *possibly* clever idea to test my option B. Restrict the head -> thermostat hose when warm. When cold, this line feeds warm water to the thermostat, and aids in quick warmup. I'm not sure it is closing entirely once warm though. And the important part is, given the significant resistance increase from an RSX to the MR2 along the radiator routing due to increased coolant mass, I think the engine may be drawing even more from the head, thereby bypassing the radiator and heater.

Either way, I can't think of a healthy solution other then an aux pump.

Thoughts?

 

[dblotii]

So Brandon/Dave/All,

I've had another thought regarding the cooling issues that could be worth some conversation. My car is up and running (yay!) and it feels great having traction in first gear. :biggrin:

My fans are on, my system bled, my radiator working wonderfully. With fans on: nearly room temperature air on the cold side, very hot air on the warm side, coolant pipes similar.

However, when idling for long periods of time, temperatures slowly creep toward dangerous ranges (206-208).

So, what can this mean?

It resolves to two possibilities for me.

A ) Coolant simply isn't moving fast enough at idle.

B ) Too much hot coolant is being re-introduced back into the engine, and not enough cold coolant drawn through the radiator.

With Brandons aux water pump, I think we solve both possibilities.

However, I had a *possibly* clever idea to test my option B. Restrict the head -> thermostat hose when warm. When cold, this line feeds warm water to the thermostat, and aids in quick warmup. I'm not sure it is closing entirely once warm though. And the important part is, given the significant resistance increase from an RSX to the MR2 along the radiator routing due to increased coolant mass, I think the engine may be drawing even more from the head, thereby bypassing the radiator and heater.

Either way, I can't think of a healthy solution other then an aux pump.

Thoughts?

One reason for this problem can be running a single poppet thermostat instead of the OEM style double poppet. The OEM style thermostat is designed to shutoff the bypass flow when the coolant temp rises above the thermostat set point. On a stock K20, the open thermostat should close all of the bypass paths except the one through the oil cooler.

 

[dblotii]

So Brandon/Dave/All,

I've had another thought regarding the cooling issues that could be worth some conversation. My car is up and running (yay!) and it feels great having traction in first gear. :biggrin:

My fans are on, my system bled, my radiator working wonderfully. With fans on: nearly room temperature air on the cold side, very hot air on the warm side, coolant pipes similar.

However, when idling for long periods of time, temperatures slowly creep toward dangerous ranges (206-208).


with the fans on?


So, what can this mean?

It resolves to two possibilities for me.

A ) Coolant simply isn't moving fast enough at idle.

B ) Too much hot coolant is being re-introduced back into the engine, and not enough cold coolant drawn through the radiator.

see my comment about how the double-poppet stat is supposed to work

With Brandons aux water pump, I think we solve both possibilities.

However, I had a *possibly* clever idea to test my option B. Restrict the head -> thermostat hose when warm. When cold, this line feeds warm water to the thermostat, and aids in quick warmup. I'm not sure it is closing entirely once warm though. And the important part is, given the significant resistance increase from an RSX to the MR2 along the radiator routing due to increased coolant mass, I think the engine may be drawing even more from the head, thereby bypassing the radiator and heater.

not if the thermostat is working properly. the thermostat is designed to sut that flow path down when the coolant gets hot

Either way, I can't think of a healthy solution other then an aux pump.

Thoughts?

see my comments above

Dave

 

[gawdzilla]

Is the Stewart pump strong enough to skip the mechanical water pump entirely? I.e running a block off plate

 

[BottledFedMR2]

So Brandon/Dave/All,

I've had another thought regarding the cooling issues that could be worth some conversation. My car is up and running (yay!) and it feels great having traction in first gear. :biggrin:

My fans are on, my system bled, my radiator working wonderfully. With fans on: nearly room temperature air on the cold side, very hot air on the warm side, coolant pipes similar.

However, when idling for long periods of time, temperatures slowly creep toward dangerous ranges (206-208).

So, what can this mean?

It resolves to two possibilities for me.

A ) Coolant simply isn't moving fast enough at idle.

B ) Too much hot coolant is being re-introduced back into the engine, and not enough cold coolant drawn through the radiator.

With Brandons aux water pump, I think we solve both possibilities.

However, I had a *possibly* clever idea to test my option B. Restrict the head -> thermostat hose when warm. When cold, this line feeds warm water to the thermostat, and aids in quick warmup. I'm not sure it is closing entirely once warm though. And the important part is, given the significant resistance increase from an RSX to the MR2 along the radiator routing due to increased coolant mass, I think the engine may be drawing even more from the head, thereby bypassing the radiator and heater.

Either way, I can't think of a healthy solution other then an aux pump.

Thoughts?

I think you still have air if your hitting over 200 at idle. Every car I have seen has been able to hold idle, yes without the pump it will go up to 200 but when the fans kick on it should bring the temp back down enough to turn the fans off. You most like will not have any heat or very little heat through the heater core. You are correct it have very minimal flow at idle. As for B, see David's response, he is correct. You can block off the port off the back of the head if you eliminate the thermostat. But you cannot plug it if you want to keep a thermostat, you will over heat it.

 

[BottledFedMR2]

Is the Stewart pump strong enough to skip the mechanical water pump entirely? I.e running a block off plate

I haven't tried it. We estimate that the OEM pump is running when at 4000-6000 rpms at 35-40 GPM, at idle maybe 10 GPM. The Stewart runs at 55 GPM all the time. Theoretically it just might work. Doing this would raise your cost even more. You need the block off plate, new lines, the Ktune idler pulley setup that's works with a removed water pump housing. If you were to remove the OEM water pump the cost of running just a electric pump would be near $800-1000. If you run both the GPM rate should be around 80-90 and the cost is around $500.00 The Stewart pump is $399, but it is the only "inline" pump out there, it is light and it works very well for the spyder.

 

[dblotii]

I haven't tried it. We estimate that the OEM pump is running when at 4000-6000 rpms at 35-40 GPM, at idle maybe 10 GPM. The Stewart runs at 55 GPM all the time. Theoretically it just might work. Doing this would raise your cost even more. You need the block off plate, new lines, the Ktune idler pulley setup that's works with a removed water pump housing. If you were to remove the OEM water pump the cost of running just a electric pump would be near $800-1000. If you run both the GPM rate should be around 80-90 and the cost is around $500.00 The Stewart pump is $399, but it is the only "inline" pump out there, it is light and it works very well for the spyder.

Almost every OEM shoots for roughly a 10 degree C temp rise across the whole engine at full-load. To accomplish this it takes about .3GPM for each horsepower of output. So the Honda pump should be putting out at least 60 GPM at rated power speed. If you want to use an external water pump don't forget to figure out how to plumb the bypass circuit. You need circulation within the engine during warm-up and whenever it is cold out, for a number of reasons. You also don't want to dead-head the electric pump when the thermostat is closed.

Dave

 

[BottledFedMR2]

Almost every OEM shoots for roughly a 10 degree C temp rise across the whole engine at full-load. To accomplish this it takes about .3GPM for each horsepower of output. So the Honda pump should be putting out at least 60 GPM at rated power speed. If you want to use an external water pump don't forget to figure out how to plumb the bypass circuit. You need circulation within the engine during warm-up and whenever it is cold out, for a number of reasons. You also don't want to dead-head the electric pump when the thermostat is closed.

Dave

Well the 60 GPM will be in the total Honda setup. That pump with the Toyota setup is not running at 60 GPM. We currently haven't routed the bypass but we have already discussed the addition of it. We have enough room right next to the pump to run a bypass. We have also discussed adding manual valve's to turn the bypass on and off. Stewart told us it was a unrestricted pump but we have found out without the pump on we can VERY quickly reach temps in the 200's and within second of turning it on we can drop 30 degrees, leaning there is restriction. The purpose of the valve would be incase of pump failure at the track we could then at least drive the car back without needing a tow. BTW currently the car is able to heat up within a few minutes to normal operating temps.

 

[dblotii]

Well the 60 GPM will be in the total Honda setup. That pump with the Toyota setup is not running at 60 GPM. We currently haven't routed the bypass but we have already discussed the addition of it. We have enough room right next to the pump to run a bypass. We have also discussed adding manual valve's to turn the bypass on and off. Stewart told us it was a unrestricted pump but we have found out without the pump on we can VERY quickly reach temps in the 200's and within second of turning it on we can drop 30 degrees, leaning there is restriction. The purpose of the valve would be incase of pump failure at the track we could then at least drive the car back without needing a tow. BTW currently the car is able to heat up within a few minutes to normal operating temps.

I wasn't referring to a pump bypass, I mean you need to pay attention to the bypass that allows coolant to circulate within the engine when the thermostat (main poppet) is closed. Also you have to figure out how not to dead-head the electric pump when the thermostat is closed.

Dave

 

[BottledFedMR2]

I wasn't referring to a pump bypass, I mean you need to pay attention to the bypass that allows coolant to circulate within the engine when the thermostat (main poppet) is closed. Also you have to figure out how not to dead-head the electric pump when the thermostat is closed.

Dave

The existing "warmer hose" should work for that. The bypass around the pump will give relief from dead-heading the pump.