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Posted by: Rotary'14 Oct 23 2011, 06:09 PM

I've been slowly gathering steam on this. After talking to the folks at the G&R flesh roast,, I'd thought I'd share some pics and thoughts.

I don't want to do any major cutting on my conversion. My goal is to have 2 usable trunks, and a car that can be easily converted back to a stocker. There have been a few threads where the possibility/impossibility of an engine bay radiator. Here's my take on it. I believe that at 25+ mph there is a low pressure spot behind the back window. I think this will be enough to suck air up through the engine compartment.
I would love to hear some constructive criticism.

-Robert


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Posted by: Rotary'14 Oct 23 2011, 06:15 PM

This is how I am mounting my oil cooler. The PO of my car got rid of the brake proportioning valve, and replaced it with a T. I am going to use both of those original mounting points to help hold up my oil cooler.


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Posted by: sixnotfour Oct 23 2011, 06:16 PM

Nice !!

You tell Us , Does it work ??

Posted by: Rotary'14 Oct 23 2011, 06:18 PM

I relocated my fuel pump to the front trunk and I made up this assembly. I had to drill two small holes for the fuel lines from the tank to the pump and back.


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Posted by: Rotary'14 Oct 23 2011, 06:20 PM

I sure hope it works,, I am engineering this by the seat of my pants. I think I should be idle testing by next month.

-Robert

Posted by: Rotary'14 Oct 23 2011, 06:23 PM

I almost forgot,,,, my radiator can swing open for access.


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Posted by: kg6dxn Oct 23 2011, 06:24 PM

Nice! If you have the radiator fans blowing up it may just work. A better spot for the oil cooler is directly under your radiator. Use those fans to pull air through.

I'm subscribed...

Posted by: sean_v8_914 Oct 23 2011, 06:30 PM

Good to see you today
where is the air burp/bleeder valve?
or do you bleed it in teh swing open position?

Posted by: mark21742 Oct 23 2011, 07:51 PM

I want to know more about this swap.....a lot more

Posted by: Rotary'14 Oct 23 2011, 08:14 PM

I plan on bleeding my system in the swing open position thru the brass fittings I screwed into franken-radiator.

-Robert

Posted by: Dave_Darling Oct 24 2011, 12:39 AM

You may find that the engine lid actually has a high-pressure zone above it. So you may need to set up the fans to push the air down through the radiator instead of pulling it up through.

--DD

Posted by: Rotary'14 Oct 24 2011, 06:43 AM

I can reverse the direction of the fans if needed,, where did you get the info about the high pressure?

-Robert

Posted by: bandjoey Oct 24 2011, 07:20 AM

What about the extra heat softening up the buytl holding the rear window in plane?

There's an engineering study online for 914 windflow. Google is our friend unless someone has this book marked.

Posted by: nathansnathan Oct 24 2011, 08:12 AM

Hey, Rob, I was thinking more about this last night. It's awesome to see pics. Would love to have checked it out in person!

The aerodynamic info mentioned was from that engineering teacher that autocrossed and had his students analyze the 914. They determined there was a low pressure area above the engine just behind the roll bar, but I believe it was because of the intake air being pulled from that area- could be different with the open engine compartment.

I've got an extra engine cover that I'd be willing to sacrifice to your cause.
I'm still thinking to modify the stock one would be the best/ cleanest way. I'm picturing mounting the radiator lower and then to clear the lid of the rear lid on the pivot, it would 'parallelogram' up with the lid, if that makes sense. Looks like there is some room to work with down there. That engine is little!

Posted by: matthepcat Oct 24 2011, 08:59 AM

I seem to remember a thread of someone doing an engine compartment radiator, and never being able to keep it running cool enough.

I believe his was a Subaru engine. In the end he put it in the front trunk.

The bottom line was that there was not enough airflow.

Posted by: Andyrew Oct 24 2011, 09:17 AM

Overflow tank?

This is a great idea, but I have concerns about it actually working..

Posted by: Rotary'14 Oct 24 2011, 09:19 AM

I believe you mean TonyakaVW,, he's a real rocket scientist. Yes he gave up on mounting the radiator in front of the engine. But,, there was also a guy named Scott Thatcher (who I don't think is an engineer) who did install an engine bay radiator and drove the car from the east coast all the way to the west coast for WCR05 and back. How cool his car ran? I don't know,, I wasn't there,, but I did hear he did fine on the track day.

So I would say it's a toss up. If my car overheats,, I will acknowledge you were the first to warn me. If I get it to run reliably I have just proven another less invasive method of cooling H2O in our fine little cars.

-Robert

Posted by: Rotary'14 Oct 24 2011, 09:25 AM

In the pic with the radiator tilted up,, you can see a coolant fill. There is also a overflow relief valve there, and the overflow tank will hook up there.

I have concerns about it working too,, but you never know until it's been tried. The radiator I am using is about 50% bigger than the one I used when it was mounted in the front trunk. We will see.

By the end of this week I should have my other oil cooler line hooked up and I should be able to try and start it once I sort out some minor other stuff.

-Robert

Posted by: dakotaewing Oct 24 2011, 09:38 AM

Robert -
Thatchers car was a subby motor, and the radiator was mounted vertically inside the engine compartment, not horizontally above the engine. And while Thatcher did survive the track day, I wouldn't call his car a "contender". EVERYONE at that event was concerned as to the cars ability to get the owners back home, as that motor/combo was untried at that time, and Mr. Thatchers trip was not without a few "events" (breakdowns) along the way.
FYI, our very own Mr. Darling who posted above, is also a former NASA rocket scientist...

Best -

Thom

Posted by: porsche913b_sp Oct 24 2011, 10:25 AM

Thats pretty cool thinking out of the box Robert.

Here is a pretty cheap way to figure out which way the the air flows in the engine.

How about tying 2 ribbons on the grill, one on the inside and one on the outside of the grill and drive it to see which way the ribbon flows.

But that wouldnt confirm if th VOLUME of air was adequate though

I would gladlly test it for you, but unfortunatley my car is not driveable at the moment, sorry

Anyone with a conversion wanna give a test run and see

Posted by: kg6dxn Oct 24 2011, 10:26 AM

Just remember, when a rotary overheats... It's over...

Posted by: Andyrew Oct 24 2011, 10:28 AM

I was just thinking that a rotary probably wouldnt be the best to test this with. A subaru might though..

Posted by: JRust Oct 24 2011, 12:17 PM

I hope it works for you Robert. I worry about it being able to cool a rotary but you know a hell of alot more about the motor than me. I do want to see a radiator work in the engine compartment. I still think running dual boxter radiators on the sides in front of the wheels. With an intake on the side is worth trying. I will be doing it at some point. I think it is best suited for a normally aspirated suby motor though. I wish you the best with it & hope it works.

Posted by: Jeff Bowlsby Oct 24 2011, 01:47 PM

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Posted by: Rand Oct 24 2011, 02:12 PM

My $.01 opinion is the natural airflow debate is pointless because it is not a high velocity flow like the front of the car. The factory fan was able to pull plenty of air downward. Without tin, even if the natural flow is upward, it's not high speed / high pressure. It is the fans that are going to need to force the air through the radiators at sufficient speed. Good fans and good shrouding will be critical. If they pull it upwards from the bottom, they are pulling hot air. If the pull it downward from the top, it's cool air. I doubt the natural free flow direction is enough to affect temps as much as the temperature of the air being pulled by the fans.

The cool thing here is Rotary'14 is taking this on for real. It's fun speculating, but I'm anxious to hear the actual results. I'm just worried about the engine during testing, since rotaries make TONS of heat and don't take kindly to overheating. Careful!

Posted by: Dave_Darling Oct 24 2011, 05:22 PM

Jeff's tuft testing photo there matches the pics I've seen or 914 race car tuft testing. The air actually goes forward along the rear deck lid and into the engine bay.

--DD

Posted by: Rotary'14 Oct 24 2011, 05:35 PM

OK,, I can rig the fan to blow in. I like that better anyways. Thanks everyone for the discussion.


-Robert

Posted by: kg6dxn Oct 24 2011, 06:29 PM

Those fans will work best pulling air not pushing. It's like trying to push a rope; don't work to well. Put the fans on the bottom if you intend to pull air down. In fact, if you have room to lower the rad, you can fit the engine cover back on. Even if it is just pinned on.

Wishing you the best of luck! Keep posting pictures! I love this thread!

Posted by: Vacca Rabite Oct 24 2011, 09:01 PM

flip the fans and put a GT lid over the radiator. Adds a little protection to the radiator, and since the GT is double grill material it will not block airflow.

Helps keep your 914 looking like a 914 too.

Zach

Posted by: moparrob Oct 24 2011, 09:10 PM

on the GT lid.

+1 for the puller fans with a good shroud as well. I'll bet it ends up working just fine. The conversion sounds awesome and I am now subscribed.

Good to have a 914 brother in LA. What part of the city are you in?

Posted by: Rotary'14 Oct 25 2011, 06:46 AM

A GT style lid has always been in the plans, weather I can build one or not is another story. I will be following "kg6dxn" suggestion, and will be moving the fans to the bottom of the radiator. Then actually I might fit the stock lid modified like a GT. I am trying to keep it as stock looking as possible.

-Robert

Posted by: Rod Oct 25 2011, 06:56 AM

I think you need to look underneath the car to get enough cooling power... Have the fans blowing down as there is deffo a low pressure zone above teh engine lid, but I think you'll have most success by putting a plastic strip along the bottom of the car in front of the engine bay cutout - This will create a high pressure area under the car (Like the original two small flaps) and with teh low pressure above and the high pressure below you'll create a suck through.

If you can I'd arrange the fans to blow up when stationary and at low crawling speeds and then reverse to blow down when you're going over say 30kph..

But I really do think that most engine bay cooling solutions have failed because of the lack of a high pressure point below the engine bay - and it's easy to achieve..

Posted by: Rotary'14 Oct 1 2012, 08:33 PM

Here's a long overdue update on the cut-less conversion. I have mounted and wired pretty much 90%. Fuel injectors are mounted and my engine bay fuel lines ran.
My fuel lines are mounted and my fuel tank is POR-15ed and ready to go,,,,, but Dirk Write has a hold of me and I want to fix my fresh air blower "since I'm there". I have sat on this long enough for my foosball addiction (from a previous life) to side track me and derail me getting my car drive able to the great G&R this year,,,, BUMMER!!

I some how plan to wire up an "external" fuel source and try to fire up the ole girl. There's water in my coolant hoses,, and a mysterious loss of water to go with it,,,,, but nothing external that I can see,, and it's really slow so It might be thru my engine (because it's been sitting sooo long). I hope to fire her up and heat cycle it a bit and see if the leak goes away.

I need to find a machinist who can make a throttle arm for me,, I need a .25" X 2.5" 1/8"thick piece of steal shaped into a throttle arm with a "D" shaped hole on one end,,any suggestions in So. Cal.?

I will post some pics soon as they are on my phone,,


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Posted by: Rotary'14 Oct 1 2012, 08:39 PM

Engine bay fuel lines,,


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Posted by: Rotary'14 Oct 1 2012, 08:41 PM

Engine side,,


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Posted by: computers4kids Oct 1 2012, 10:45 PM

I have a stack of lids if you need one close to make a GT lid from. When I had a life, previous to going back to grad school, I made about 25 of them. I'll be glad to help you if you want.
Mark

Posted by: Jeffs9146 Oct 1 2012, 11:37 PM

If you are loosing water make sure you pull the plugs and turn the motor over before you try to start it! Just in case it is leaking from the head into the cylinders!!

Posted by: Rotary'14 May 18 2014, 06:52 PM

I have made my own GT style lid from two chrome grills. It's held down with quick-latches. I think it looks OK for now. until I clean up my cooling system a bit, speaking of which,,,
I've driven her on 100 degree days now, still no overheats. I was a bit low on water too. On normal days my car is a cool running cat. I want to sort my suspension, but I don't know where to begin. I had a fellow teener hop behind the wheel of my car for an evaluation run. John was pretty impressed, despite the fact that he wasn't used to my gear box and couldn't find 1st. When the test drive was over,, I suggested that he pull on the ebrake lever with some force,,, only one side is currently working. Pop! went the cable inside the cabin. bummer,, oh well I have a wtb add up.

anybody local want a ride? I have the FI 95% done and she feels pretty good! I'm thinking about adding heat now,,,,

-Robert


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Posted by: 1stworks Jun 3 2014, 01:01 PM

Nice work!!
Thanks for updating.

Posted by: mikesmith Jun 3 2014, 04:35 PM

I'd love to see more details of your latch setup...

Posted by: 76-914 Jun 3 2014, 05:22 PM

Damn Robert, I think we should make you the Poster Child for the "Slackers Thread".

Posted by: Rotary'14 Jun 3 2014, 07:17 PM

I bought some quick latch minis,, they're a modern take on the hood pin. All you got to do to remove the grill is push down on the button in the middle.


https://www.youtube.com/watch?v=6_8Oux9Zi5Y

-Robert


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Posted by: Rotary'14 Jun 3 2014, 07:20 PM

When I saw the slacker thread get started,,, I was a bit worried about getting called out.

My car runs now and is undergoing continuous improvement. so I don't worry so much now,,,,

Posted by: Mueller Jan 28 2015, 09:16 AM

Nice build there Robert....

I really like those latches!

Posted by: thelogo Jan 28 2015, 11:11 PM

http://www.mr2oc.com/showthread.php?t=279581#/forumsite/20711/topics/279581



I have seen these on Mr2 s an Baja bugs

Scoops or snorkel s

The Mr2 has them positions ed right where the 914 sail panel would be
Are they using it for intake ram air or cooling air

Where are the Mr2 radiator s at anyway

Posted by: Bleyseng Jan 29 2015, 10:25 AM

Time to install a little more HP with this engine. 250HP Turbo 2.


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Posted by: Dave_Darling Jan 29 2015, 10:41 AM

MR2 radiator is up front, just like the X1/9 that it is based on...

--DD

Posted by: rick 918-S Jan 29 2015, 11:46 AM

with the engine tin in place. Otherwise all bets are off. My Alien circulates the air up and over the targa bar. GT style grille. We just about cooked crossing the desert with the targa top off.