to_slow

iTrader: (3)

I got the greddy front mount and the koyo rad.Well i hope i figure something out that will work .Thanks 4 all your help
Dan

JOHNO

i have had similar problems. i have an apex fmic and a koyo. the stock fans wouldnt fit. they were hitting the crossmember so i went with aftermarket slim fans. they were just not pulling enough air through the radiator. i was seeing water temps of 105 - 110 c on my pfc commander. i put the stock fans and radiator back in and saw temps of 90 - 98 c. as soon as the fans came on at 98 within 2 min water temps were back to 90. keep in mind i live in florida where the ususal temp is like 90 - 100 f. now i am stuck with a raditor and slim fans i dont know what to do with.

johno

user 84205

Johno,
I have the same set-up man..The radiator is made for the track(curcuit), so it needs a lot of air pumping threw it. Now if you go to www.jt-imports.com and check the BILLION section you will see a dial variable fan controller, its very easy to put in and my temps went from 96-102 temps to 87-91 temps always... You can actually control your temps, and I have had no problem since then....
Jason

Node

iTrader: (1)

Strict 1/4 mile drag racers DO NOT NEED intercoolers like daily driven cars do.
They can have them, and will usually chill them (ice) but they do not need them to keep down the temps for long periods of time like daily driven cars. They are running less than a minute in positive boost (if you consider burnout, launch and the 10 seconds). A lot do not even use intercoolers because it's not necessary for drag racing (sometimes because of alternative fuels).

Rx7maluco

iTrader: (1)

Haltech Elite 2500
Borgwarner s366
900cc
1700cc
Walbro 440
Large street port
60mm wastegate
Koyo rad
Tial bov
Single oil cooler
Greedy style fmic
Gutted thermostat
Under tray
Wrapped downpipe
Shitty turbo blanket (need one that actually works)
0.9 rad cap

Motor was built for 550hp .(3500 miles ago)
Tuned to 10psi
Running motorcraft Vic-10-A2 coolant 50/50
Fan comes on @189 turns off @186



So I had the cooling system just checked (pressurized) and its fine . Had my radiator also checked for debri or being clogged also ok. I know the FMIC holds bk a lot but got damn I see temps high as 210 -219 and they stay steady on the freeway weird. Like last night driving back home 4hr drive . 10pm it was cool outside but 219 and steady cruising at 65- 80 . I down shifted and punched it and bam temps went down to 188 lol. Wtf. It seems to come down when I punch it or downshift keeping the rpms up while accelerating or coming to a stop. Stop and go traffic lately goes up to 219 also. What's crazy is that if I pop the hood the radiator is not fully hot. Facing the engine the driver side of the radiator is some what cool. Where u can lay your hand on it.

The car runs solid other than that.

Ducting isn't the best i.e.: need the piece that goes on top of the radiator so air won't escape from the top , foam on the side of the radiator.
but from different setups ive looking/reading a lot of people seem to be running cool
Already spent 12k on the engine and misc. just under the hood not including my turbo kit. So you can imagine how stressful it is to not having a perfect running car lol

Any ideas on what I can look at would be great. And please don't tell me to go get a vmount.

Slides

Did you block the bypass if running without a thermostat?


I'd put a thermostat back in myself.

Rx7maluco

iTrader: (1)

By pass is blocked just the middle of the stat is out ... my engine builder is the one who set it up.. pretty much all the cars he builds runs with a thermostat missing the part in the middle.. the car warms up just fine. But sometimes it will run hot city and freeway like I mentioned..

fendamonky

iTrader: (6)

Kudo's for searching, but you could probably have started a new thread instead of bumping a 15 year old one..


As I understand it, you're complaining that you're hitting high temperatures while in low/slow traffic, right?

Things I'd check (just to be safe): ensure that the coolant system is properly bled, and there aren't any air pockets in there.

Install a proper thermostat!!!! You're driving a street car, the thermostat is there for a reason. Slowing the travel of fluids through your radiator will help your coolant extract as much of a heat exchange from the process as it can manage. Pushing as much fluid through there as quickly as you can may *seem* like a good idea, but it's really counter-intuitive. Decreasing the flow rate some will improve your cooling issues.

Rx7maluco

iTrader: (1)

If u read it carefully it's not only on slow but also on the freeway.. And on top of that temps do go down when I punch it.. cooling system is I. Perfect working order. . Amd i bumped this bc it wasnt fixed and its the same problem. Been searching for wks.. I will try a smic later to see if temps will change . But my engine builder is the one who told me to run it this way. And once again if u have read it right it's been working for other people . (Do u catch the drift?) Sorry if I sound like am add. Just want everyone to catch everything and by these answers here doesn't seem like they are reading the entire problem I posted.. this is a reputable rx7 mechanic and by all means iam not saying he's perdect.

fendamonky

iTrader: (6)

That's cool man... Though, if you read what I wrote carefully you'll see that I first suggested you bleed your coolant system to ensure you don't have any air bubbles floating around in there.

Pressure testing the system will tell you if you've got a bad coolant seal(s), but I'm not aware of it magically fixing air trapped in the system though. That's a separate thing.

ZoomZoom

iTrader: (2)

Getting air out of the coolant system is tricky. What you need is a Lisle funnel and directions on how to use it to bleed out the air.

silentblu

iTrader: (1)

Are your fans working correctly? Low, Medium, High?
What kind of pulleys do you have? Punching it and having it drop sounds like a flow problem. Not enough flow at low rpm.
You also probably have a Non N-Flow koyo radiator, looks up the differences and you'll see why. The driver side is the return or "cooled off" coolant.
You should also probably switch to something with more water then coolant, 50/50 is not needed.
Your AST or coolant reservoir return is also important to maintaining a proper cooling system for air removal.

My temps never reached that high with a greddy triple and koyo radiator (non N-flow), no ducting/undertray either.
Also, went from coolant/water to straight evans. I did not see the average temp rise as most or the product indicated it should.

Neutron

iTrader: (10)

+1 on this! Definitely get a Lisle funnel and make sure all the air is bleed out of the system. Not hard to use but time consuming. It may take a few full heat cycles to get all the air out. That is getting the car completely cold and fully warmed up a few time with the Lisle funnel. Chances are a shop is not going to take the time to do that.

Also try and just run a normal thermostat. There is no benefit on over thinking this. An upgraded radiator cooling system with the factory water pump that is working properly will never run too hot with the thermostat and will not run too cold either. Keep it simple man.

If coolant is getting through the bypass port at all time, trying a normal thermostat will also correct this problem. I have no idea what would happen if the water pump was trying to pull coolant from the bypass circuit and radiator circuit at all times. I am sure wired stuff would happen.

Rx7maluco

iTrader: (1)

I bled the system 3 times. And not including the last time my mechanic did it when he flushed the system after the test. I drove home 4hr drive the nxt day I pulled the radiator off went to a professional radiator shop and had my koyo flow tested and it was fine , no need to pop it open. So I got home and put it together.

Rx7maluco

iTrader: (1)

One of the first things I did was buy one.. remember my stat is gutted so it's not that hard to bleed it ..

Rx7maluco

iTrader: (1)

I talked that out with my tuner Nelson @RRR and he is aware of this thermostat mod and said it's not the problem... the big part of the thermostat is there. Like I said . I'm looking for ideas on what to look for, I know how to bleed the system , I even tried different ways. The car runs cool for a bit then it goes to 195-219 . Funny how no one read that or if they did they ignored the fact the once at 219 sometimes I punch it and temps go down.. cruising at 65-70mph. I know the fmic will block some air but there's a lot of people here running a fmic with lower temps.

Ps: I've been driving 4 fan hrs to drop the car off at the shop who built the damn motor and he can't figure out. He's saying it's the fmic. But I refuse to believe that bc there were at least 3 other fds there running a fmic and it didn't run as hot one was a infini twin pushing 405+ on 16psi on koyo fmic and all .. plus my past 4'fds all had fmic and no problem..
and I had times I left my rad cap off and kept adding coolant everyday little by little to ensure no bubbles then bought the lislie funnel. And due to having a gutted sthermostat(please understand that a gutted thermostat does NOT mean iam running without it) lots of threads on this here. So that's not the problem

Rx7maluco

iTrader: (1)

Stock pulleys in place
Fans working properly
No ast . (Don't need to go down that route)
So I thought about it too being a flow problem that's why I had my rad checked and it's not blocked. Even at low rpms I see low temps sometimes. And I read about the Evans coolant and I don't think it's for me.
I did have about 40% coolant at one point didn't help really.. what's weird to me is the steady 219 for about 20min give it or take of cruising. But goes down when I punch it and cruise again. Lol

Ps: you are right I have a N flow koyo..

Carl

iTrader: (2)

Are you positive that the bypass is plugged. It requires threading the bypass port below the thermostat and installing a pipe plug.

The normal thermostat works by leaving that port open when the thermostat is closed (in cold condition). With the port open a small amount of water can still flow through the system bypassing the radiator. When the thermostat opens, the bypass is blocked by the descending flange on the thermostat, forcing all the water to flow through the radiator.

My race car does not have a thermostat, but that bypass is plugged. There are issues without the thermostat when the ambient air is cool/cold, but racing in SoCal that does not happen too often.

Rx7maluco

iTrader: (1)

Yes 100% . I asked my mechanic and he said no other mods other then to the thermostat itself was done ..

update : I tightened the alternator a little more and did a quick trip to usps then bk home no 219 . Max was 208 then bk down.. so seems to be in check as of right now. I will be working on the upper and sides radiator air passages to ensure proper flow with the fmic. I'll keep this updated..

dguy

iTrader: (8)

I've got to ask, have you even tested the sensor that you're tapping for your temps? I've only seen one get wigged like yours but it can certainly happen.

Rx7maluco

iTrader: (1)

Yes, by matching the haltech reading with a heat gun. Same reading. So far the car has not acted up 1 hr of driving stop am driving go also freeway included. I find it hard to believe that it was the belt that was somewhat loose. But after a good amount of time researching it can happen fen though my belt didn't seem loose. But like I said so far so good no more problems.