Another thing we are going to do is get ride of the MR2 "over flow bottle" the Toyota's coolant setup is different from the Acura as it doesn't have a real overflow . We are purchasing some Ktuned parts in the GB that's allows to get a cylinder head temperature as well as increase the pressure on the system which we are hoping will decrease if not eliminate the cavitation.

 

So after 3 months with the swap done I have decided to put the rear interior back in. But I have a dilemma; the Fuel line cover doesn't fit with the -6an 90* fittings I have tried. The fitting I have now is the smallest one I could find but the cover still doesn't seat correctly. Now before I go have this thing hammerformed, has anyone found a fitting to allow the cover to fit?

[/URL]

[/URL]

 

Found this on MR2 Roadster.com (sorry if this has already been posted) couldn't resist.

http://m.autoevolution.com/900-hp-t.../900-hp-toyota-mr2-goes-all-need-for-speed-in-arizona-street-racing-105637.html

 

so i think i finally got my k20a2 swap's coolant bled. i do tend to agree that the belt driven honda pump seems underdriven, given the difference between a typical short run front engine setup vs. our mid engine setup. i notice a significant increase in flow (via visible coolant temp drop) when the engine is brought above 3800 rpm. i vacuum bled the system. one of the mistakes i was making was overfilling the expansion tank and capping it too early, leaving no room for expansion and purging of the air bubbles. i guess it was my fear that the tank would go empty and suck in air. another thing i read from the 2zz swap coolant bleed tips was to restrict the upper return on the expansion tank. i added a small restrictor, and also elevated that hose before it enters the tank. seems to have helped... maybe let air through the top hose instead of a steady flow of coolant? heat seems consistently warm now. btw i am running the k24 water pump, the one without the water outlet for the k20 oil warmer. not sure if that makes a difference.

 

IF you keep ALL oem lines intact and plug the heater core line coming out of the head (just like the 1zz) and fill it properly, you will have zero cooling issues and it will act IDENTICAL to the 1zz setup

When you start adding a bunch of aftermarket shit, deleting lines, etc. you will run into problems.

The 1zz celica water pump is the same part number as the 1zz MRS pump.

 

What exhaust headers are you using in your K20 swap? My only problem with the PPE headers is that they hang kind of low and will be even lower in a k20 than a k24.

Dave

 

PPE. It does sit a little lower than i'd like. it also comes very close, if not barely touches the OE heat shield for the intermediate shaft. neither should move WRT each other so i guess it's ok.

if you plug the heater core line coming out of the head, what do you connect the heater core to?

Dave

on the K, there are two heater connections on the motor. one that is next to exhaust port #4. I believe people are calling this the feed. The other is a hard pipe that comes up beneath the intake manifold and sits near the transmission pointing rearward. if you trace the hard pipe it connects right by the tstat housing. I believe people refer to this as the return. I'm using the tstat housing connection for heat, and blocking the exhaust port 4 connection with this: https://www.jhpusa.com/store/pc/viewPrd.asp?idproduct=7004

 

on the K, there are two heater connections on the motor. one that is next to exhaust port #4. I believe people are calling this the feed. The other is a hard pipe that comes up beneath the intake manifold and sits near the transmission pointing rearward. if you trace the hard pipe it connects right by the tstat housing. I believe people refer to this as the return. I'm using the tstat housing connection for heat, and blocking the exhaust port 4 connection with this: https://www.jhpusa.com/store/pc/viewPrd.asp?idproduct=7004

*** Edit, the below is mis-information. My understanding was, in fact, incorrect!! ***

Hey bud. I think this may cause some unexpected behavior. For example (and this is all speculation on my part,) I think your heater system flow will reverse course from OEM. The original feed will now be at the lowest pressure area, and the original return will be near a high-ish pressure section (near the radiator inlet). Another possibility is that in cold weather, I'm not sure whether you'll have hot coolant available for the heat exchanger in cabin. The thermostats temp is controlled by the radiator outlet temperature. As such, it may remain mostly closed for the duration of your drive (as it flows through the bypass route). Finally, it may take a long time for the heater core to come up to temperature when compared to OEM.

This is all assuming that I actually understand the coolant routing in Spyders however. *** Edit: DOH!! *** Good luck!

 

Not sure I completely agree with the "overflow tank" style vs. "expansion tank" style thoughts, Brandon. Nor the "track legal" points. What track rules are you referring to? Any real racing will require water anyway. Coolant is strictly banned, which makes blowing the expansion tank or dumping from your overflow tank no different.

I always felt expansion tank style was superior and preferred. e36s run the same expansion tank style that the mr2 has. track going e36s "upgrade" to the expansion tank style. it is supposed to be a self bleeding system when implemented correctly with the expansion tank located at the highest point. It's probably why the market for coolant swirl pots also exists.

I believe the problem w the k swap is
a) improperly bled system
b) sub optimal pump flow. too low at low rpms, and cavitation at high rpm. plus the much longer coolant runs. that's where a well regulated electric pump can assist the mech pump, or replace it's function altogether. I don't think changing to an overflow tank with high pressure cap is the solution.

Either way, my plan is to keep pretty stock k20a2 power, but i'm still interested to see the electric pump results.

 

I'm referring to open track days and autocross stuff, where the rule's are more "preserve and limit clean up to the track." If its water based then yes your absolutely correct, most people are going to be running coolant at these event's though. Also, by elimination this bottle I'm hoping to also be able to increase the system pressure. I believe the OEM cap is only rated to 15-16 lbs, where as the Honda has a an aftermarket one which I can increase pressure to 19 lbs. this will possibly help with preventing cavitation. I am hope the nail in the coffin with be the water pump. Again the other benefit is I can monitor cylinder head engine temp's with this plate. Increasing the pressure will decrease the capability f cavitation as Dave previously mentioned.

 

Another quick update:

Battery relocation. I'm sure others have done this before, but here's how I got my battery to the front right. It looks like OEM Spyders are left rear heavy. I would have preferred to hang this where the windshield reservoir is, but didn't feel like either losing the bottle, or fiddling for hours. So I put mine on the frame/over the steering rack.

If you take the OEM battery tray and turn the bottom bolt hole such that it lays flat, the side of the tray and the front upright are near enough to be tacked/welded onto the frame and cross member. Finally, one of the original bolt holes at the bottom of the tray align over the other side of the same power steering bolt. Then you can just run one final upright support (not pictured) and be done. I'll have a certified tech inspector check it out and get their feelings. But it was pretty quick and simple. So if I had to re-work it I wouldn't mind.

Exhaust time. I've purchased a used PPE such that I can use the cat converter for emissions test goodness when it comes around. However I'll be modifying one of the first gen R-Crew headers soon. Below is a relatively clear and wholistic image of the PPE system. The R-Crew, and possibly other Tri-Y headers from some of the FWD swap crowd appears to clear the cross member with a few millimeters. It protrudes from the rear bumper by 7"-10" unfortunately. However, assuming we used the same diameter tubing, it can be modified to fit without compromising scavenging (I think).

Here's the thought. At the end of the first 2-->1 merge collectors, simply cut and replace the straight tubing with 90 degree elbows pointing up. We seem to have the real estate to play with at the new hypothetical exit to either: a) add the beginning 3"-3.5" exhaust piping elbow to begin it's routing/cat converter, or b) dump into a center entrance - dual exit oval muffler. I think i would prefer the former, but the later appeals to my lazier side. Thoughts?

Fun pics.

Little man helping put the tail light on. So much helping.

The Honda valve cover is pretty conspicuous.

The swap and bar are really the only work I've done to the car so far.

 

This entire thread is becoming useless. Only speculation with absolutely ZERO data and WAY too many "I think"s.

Answer these questions.
Which way does coolant flow in the 1zz system?
Which ports does the 1zz use and where do they attach on the motor?
Do 1zz's have cooling issues?
What are you changing between the 2 systems?

 

This entire thread is becoming useless. Only speculation with absolutely ZERO data and WAY too many "I think"s.

That takes time and money. I have to money just sit tight and we will get some answer's but we have to wait for parts in the mail.

 

You don't need the heater line on the k head and that's a fact. Plugging it is okay.

The 1zz system works well. Sometimes upgrading the radiator is too efficient for some people, even with the k series. I have a koyo and it takes quite some time to warm up during the winter.

I don't get this nonsense about 4-5 extra feet of tubing. You're pushing a liquid. Volumetric efficiency is not as important as an air system. That's why you don't see air to air intercoolers in the spyder.


Sent from my iPhone using Tapatalk

 

I haven't been on track but I get hot air if I want at idle not at 3k+ rpms.

 

some people got it, some people dont.


Is anyone having problems with this setup?

1) keep all OEM spyder coolant lines and reservoir
2) connect the passenger side hardline hose to thermostat (an aftermarket hose may be needed here)
3) connect hose that comes from driver side hardline to OEM upper coolant neck (no aftermarket radiator cap on this)
4) KEEP the bypass line that goes from the back side of the thermostat housing and under the intake manifold. Connect this line to the line that goes to the heater core.
5) plug the port that comes straight out of the header.

 

What do you guys think about setting up a Sub-forum under Performance Modifications? As this swap picks up, I think it would be nice to organize and sticky all the hard work you've found. Then we could have discussion threads (like the coolant one) that don't derail efforts.

 

KSwap headers; K20

I am not sure what the best option is for a header for a K20 in the Spyder, but this is how I see it:

The PPE Kswap header looks reasonable but I think it sits too low for a K20
The TSX OEM header can be adapted easily with a custom downpipe, but it is a bit heavy and performance is limited
Most KSwap headers will clear the crossmember, but most are too long to fit without extensive modifications before the last merge
The K-tuned KSwap headers (like the 4-2-1 and the Ram-style) look like they are short enough to fit without extensive modifications and offer reasonable performance.

Any other points of view?

Dave

 

I am not sure what the best option is for a header for a K20 in the Spyder, but this is how I see it:

The PPE Kswap header looks reasonable but I think it sits too low for a K20
The TSX OEM header can be adapted easily with a custom downpipe, but it is a bit heavy and performance is limited
Most KSwap headers will clear the crossmember, but most are too long to fit without extensive modifications before the last merge
The K-tuned KSwap headers (like the 4-2-1 and the Ram-style) look like they are short enough to fit without extensive modifications and offer reasonable performance.

Any other points of view?

Dave

I can have PPE make the header just a 1/4 inch shorter in the runner's.

 

Turbo. LoL


Sent from my iPhone using Tapatalk

 

Hey guys. I put together a few side by side shots which may help. Album

PPE on the left. R-Crew Gen 1 on the right.

I can verify that the R-Crew clears the cross member, barely. The R-Crew actually has better ground clearance. if you experience wheel hop, it may contact.

My plan is to put a couple tight 90 degree radius turns going up right after the first merge collectors replace their arc length equivalent. It *looks* like it will clear the bumper cover. Not sure what will happen with the bumper support.

On another note, I got my car started and driving last night. Thanks again Brandon! Great work on the wiring harness.

 

I can verify that the R-Crew clears the cross member, barely. The R-Crew actually has better ground clearance. if you experience wheel hop, it may contact.
My plan is to put a couple tight 90 degree radius turns going up right after the first merge collectors replace their arc length equivalent. It *looks* like it will clear the bumper cover. Not sure what will happen with the bumper support.

On another note, I got my car started and driving last night. Thanks again Brandon! Great work on the wiring harness.

No problem, good to hear everything works. Just wanted to point of on the R-Crew, if someone has a K20 it most like will NOT clear the cross member. What size diameter pipes if the R-crew. It looks like its still a 2.5 outlet and the runner's might be slightly bigger

 

The R-Crew primaries start at 51mm. For comparison, the K-Tuned Big Tube primaries start at 48mm I think. Haven't measured PPE's yet.

 

Wow those pics really show the difference. The PPE header basically looks like a glorified OEM piece. It serves the purpose of course.

 

I haven't seen them side-by-side, but I believe the KTuned 4-2-1 is in-between the length of these 2 and will probably not require shortening to clear the rear bumper. I wouldn't be so quick to criticize the design of the PPE header. A critical aspect of 4-cylinder (tri-Y) header design is how long a path is there before the second merge, because there is pulse interference between the 1-4 and 2-3 pairings. The PPE has a lot longer length to merge than any of the OEM versions.

Dave

 

i was able to use the same header on a k20 and k24 in my civic kswap with a properly placed flex pipe. not enough room for on the spyder for this though...

 

Which header did not fit the Spyder?

 

I'm going with Stefan from ASP or Derek from ALL in Fab for my next header.


Sent from my iPhone using Tapatalk

 

This is my PLM Header 4-1 cut to fit to a custom 3" exhaust was made in house thats why looks awful, its not the best power for mid range cuz we lost power due to collector reduce but gain some power at high range I found used like 200 bucks and so far works for me

 

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.

 

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.

 

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

 

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


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

"Friends"

 

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.

 

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

 

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

 

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.