Bumper mods

[kouki-gymkhana]

Well, as you know I've been having some serious heat issues with my RB25 despite having FAL 210's mounted as pullers AND a '90 AC fan mounted as a pusher on the stock POS radiator...Finally decided to say f*uck it and did a little bumper modding (heh heh). Lemme know what you think...

PS: I'm working on fabbing up an undertray to direct more air to the radiator and sealing the 210's to the radiator a bit better so they are forced to suck air through the rad, not around it. If this doesn't work, I'll bite the bullet and and order a Koyo. Still contemplating a leakdown test to make sure I didn't blow the HG as the car overheated to point of shutting itself off when the heater hose blew on the highway doing about 90mph (All the coolant was GONE in like 30secs) and I didn't realize the car was hot because the POS stock gauge was reading NORMAL.

[Kansei240sx]

Im not going to be an *******, and im going to be 100 percent honest, that looks horrible lol.

You should either A, make sure your coolant paths in your motor arent gunked up, and make sure you have some good ducting to vent air away from your engine bay so it flows better. All that mesh is going to do is flow less air in, you have way to much mesh in your stock bumper hole, get rid of that all, its just keeping more air from getting in.

And putting those holes in your front bumper takes away from the smooth nose effect which is what makes the front end of those cars look good.

[rbsileighty]

Ducting = very yes

Holes = very no

I agree that doesn't look so good... and I also agree that deleting the mesh will help out in the flow... it's acting as a diffuser right now... lower pressure difference across the rad = less flow

Ducting the air to the rad is a good idea... might even open those side vents and duct some of that air as well, but you shouldn't be having this much trouble overheating unless you are putting out gobbs of power and loading the motor at the peak power levels for prolong periods of time.

Consider running DI water only for a few days... drain and repeat with fresh DI water, then put your normal coolant mix in with some water wetter. If that doesn't work take it to a place that will do a coolant system flush for you.

My car has no overheating issues with my 2 permacools and that FMIC you can see in my signature... I did what I'm suggesting above with mine. I'm using the stock radiator.

ebay usually has stock front bumpers for sale pretty cheap...

[Eikon]

How's your water pump? Did you ever install a new one?

If you are sure your water pump is ok.. .then your HG is probably bad.

I struggled with overheating for the first 6 months of having my RB. Checked everything.. new KA radiator, thermostat, pressure test, HG test, etc... Everything was cool. Finally found out that my water pump was competely shot. The fins were totally rusted away and gone. So it wasn't moving any coolant.

I bet I'm not the only one... hint hint.. .

I never once had to turn on my fans this summer. Seriously! The RB will cool itself fine if you have a good flow of coolant. You shouldn't have to cut holes in your bumper.

[krayton]

ducting is very important. i had to step up my cooling issues with AZ heat and track events. i did what you did with bumper venting....just not feeling the holes.

youll notice a big difference when you get the air properly directed.

[kouki-gymkhana]

Thanks for the comments guys. I'm not going to tuck tail and run like some newb because you don't like the holes but the reasons are as follows :

1.) I installed a brand new water pump and Nismo thermostat less than 300 miles ago.

2.) The car is now running with the KA condenser in its rightful place as I have ice cold AC (not ghetto rigged, mind you. It cycles on and off with the set in cabin temperature and cuts out at WOT and when the engine is overheating). The condenser adds yet another obstacle to airflow getting to the radiator. Right now the path is FMIC --> condenser --> radiator and the Hybrid intercooler is pretty friggin' dense as it is. With just the stock opening, there was very little flow getting to all aspects of the radiator.

3.) I initially believed it's an airflow issue because the car was overheating on the highway doing 60mph without dipping into the boost at all.

4.) The mesh may impede a bit of flow as you've pointed out but the holes in the mesh are actually larger than they appear in the pic as the car is angled in that photo. Also, I put it there to protect the intercooler from road debris, not for looks. (Believe me, I prefer to go without it but I've gotten a bit too much attention from riceboys for comfort.)

5.) I ran the car on the highway even after cutting the holes and the temps were as high as 110 C after only about 5 miles at 60mph on a 55 F day. It didn't overheat but clearly there's another problem going on here. At least I now know that it'll take some more work to get the temps under control, whether it's making the undertray, changing the headgasket, sealing the fans, or what.

I'm not trying to step on any toes and I appreciate and respect your criticisms. If anyone has any tips on making the undertray to divert air to the radiator, I'd appreciate the input.

[Eikon]

That's really strange that you are having such trouble keeping cool.

I am sure you have already done it... Did you bleed the air out of the system? Are you sure you don't have any air bubbles?

Have you ever tried pressure testing the coolant system?

What about your radiator cap? Is that functioning ok?

Have you tried of these air dams?http://cgi.ebay.com/ebaymotors...wItem

[Carl H]

you need ducting period.make a "ram air" box setup to force air thru the fmic thru the ac condenser and thru the radiator.also you need to make sure that air is going thru the ac condenser and thru the rad as well and not around the rad core.consider a rad upgrade as well, it works and if you are having this many problesm keeping the motor cool it will very well help alot

[RB20DETodd]

ducting is very important. i had to step up my cooling issues with AZ heat and track events. i did what you did with bumper venting....just not feeling the holes.

youll notice a big difference when you get the air properly directed.

I finaly got off my *** and made ducting, 2 peices on the side and a peice underneath and it made a HUGE differance, i was having cooling problems until i made the ducting, ducting is the key, still have to make the top peice and put in my new koyo copper core radiator along with some watter wetter and hopefully ill be done for good.

[rbsileighty]

for the ducting try and cut out a cardboard template then make it out of fiberglass...

as for your mesh... it's baffling (used the wrong word earlier) the air coming in causing low pressure behind the wire. Which creates low pressure in front of your series of coolers you have in there. I'd challenge you to take the wire out and see if it doesn't help... if it doesn't put it back in...

It's all about the delta P across the coolers... which is part of why the ducting works.

Be sure you've flushed your system... you'd be impressed to see what's in there.
Modified by rbsileighty at 9:24 PM 11/7/2005

[Sil240]

Bro if i were you i'd drain the rad, pull that beyotch out stick a hose in it make sure its flowing, then pull out the thermo and stick a hose in the motor and try and wash all the crap outta your motorCause i rebuilt mine and i saw there was TONS or rust and crud in the coolant passages

Invest in a water temp gaugeDo a leak down test, it'll tell you better whats going on if you do have bad compression

Like everyone said your not racing it, you dont have crazy amounts or power or boost

Make sure that the basics are taken care of first, then go ahead with ducting and other stuff

[Cornloaf]

your headlights are cool - but i would lose the bumper

[Rookieca18det]

I would really get some ducting done, it shouldnt take you more than about 10-15 min to make a card board template (if that much). Would also consider flushing the coolant system could just be some serious blockage. Good luck man.

[kouki-gymkhana]

U-P-D-A-T-EWell, I went ahead and picked up a KOYO radiator to see if my problem was that the POS stocker just couldn't take the thermal load of the RB. I ended up modifying the upper and lower rad mounts on the car so that I could run my FAL's as pullers and it worked out beautifully with minimal trimming necessary. There's about 1/4" of clearance between the heat shield and the PS pump now. With the Koyo, the FAL's, and an OEM aux A/C fan as a pusher, the temps now run between 75-80 C on a 70 F day. Even if I stay in the boost for a while (well, only as long as my courage lasts) it never goes above 90 C. I did take your advice and fab up a lower panel so that the air coming in through the holes I made and the stock opening can ONLY go to the IC and rad, rather than out the bottom or top of the engine bay. Works like a champ now!

PS: On a sour note, I was so excited to drive it after we buttoned everything up that I forgot to tighten the silencer in my JIC exhaust and it's now missing in action after only a short drive.

[rbsileighty]

I'd like to see pics of the rad install... sounds interesting. Glad it worked out for ya bud!

[ehacker01]

Why don't you just paint the grilles red to match the car so they don't stick out like a sore thumb? that wouldn't look bad.

[S13 Charlie]

Consider running DI water only for a few days... drain and repeat with fresh DI water, then put your normal coolant mix in with some water wetter. If that doesn't work take it to a place that will do a coolant system flush for you.

De-Ionized water actually eats metal, so unless you want your engine and cooling system to corrode away, I would stay away from DI water. Did you mean to say Distilled water?

[kouki-gymkhana]

UPDATE 2Well, I've been driving the car around for about a week now after fitting the Koyo and it's still not overheating but the coolant keeps flowing into the overflow tank and isn't flowing back into the rad as it's supposed to after the engine cools down. As a result, the temps tend to rise after sustained driving because there's less fluid in the rad. For example, I was following my bud on the highway doing about 80-85mph and the temp was slowly inching up to 90+C. As I said, it didn't overheat but I don't understand why the temp would be going up with that kind of airflow across the rad!?! I guess that means my HG is probably toast as I'd feared. SH*T!! Still not seeing any bubbles in the coolant or white smoke coming out of the exhaust though. This project is really sucking the life out of me...

[rbsileighty]

De-Ionized water actually eats metal, so unless you want your engine and cooling system to corrode away, I would stay away from DI water. Did you mean to say Distilled water?

Nope... I said "Consider running DI water only for a few days..." as it helps clean things out of the system. You run your regular coolant/water mix when you're done.

[Fenvy]

Well, as you know I've been having some serious heat issues with my RB25 despite having FAL 210's mounted as pullers AND a '90 AC fan mounted as a pusher on the stock POS radiator...Finally decided to say f*uck it and did a little bumper modding (heh heh). Lemme know what you think...

PS: I'm working on fabbing up an undertray to direct more air to the radiator and sealing the 210's to the radiator a bit better so they are forced to suck air through the rad, not around it. If this doesn't work, I'll bite the bullet and and order a Koyo. Still contemplating a leakdown test to make sure I didn't blow the HG as the car overheated to point of shutting itself off when the heater hose blew on the highway doing about 90mph (All the coolant was GONE in like 30secs) and I didn't realize the car was hot because the POS stock gauge was reading NORMAL.

nice motor and all but now that's one ugly piece of ****

some people do the silvia converison and not install the center piece, that llooks not too bad.

[kouki-gymkhana]

Hey, I know it's not pretty but for right now, it's functional. It actually doesn't look that bad in person. At the moment, my car is "all go and no show" aside from my lighting upgrades. As you can see in the photo, the car needs paint badly and will be getting aero and body work in the Spring to bring things up to par with what's under the hood. Besides, bumper skins are cheap and I cut the holes to see if it was just an airflow issue or if there's a larger issue at hand.

[gawdzilla]

funny thread x 2 TTT!

[RB20DETodd]

funny thread x 2 TTT!

You have good taste sir, the paint now this lol!!!

[Joe]

integra7 i deleted your post, give me a break. this thread was a year old. dont make idiotic comments in dead threads.