RSBro

I'm about to have the front bumper on my 03 C4S repainted and tidied up (it's way past time), and have considered buying the Rennline protection grilles for the two side and center cutouts. However, are these things really worth it? At $325 it's not really a huge cost and the paint shop I'm using said they'd install them for me no problem, but looking secondhand and even on my local Facebook group pages, etc. I don't really see these installed all that much and makes me wonder why, if the design is so 'flawed'. I do know the radiators need to be cleaned out but that's different than buying more parts for the car. I probably will keep it another 2-2.5 years, but have had it almost 1.5 years and haven't removed the front bumper to clean anything and don't see any overheating issues, so just curious from first-hand experience on this?

Mbren1979

Can't speak much about the Rennline Grills. But will say my experience. I purchased my car in june of 18. Pulled the bumper and it was amazing how much crap was between the rads and condensors. A month ago my rads both started leaking. When i went to replace them it was amazing how much crap was between them again.

Running hot or overheating is almost never the issue. It that the leaves and debris that get lodged in there become acidic and will cause the condensors and rads to leak. Doing anything you can to stop the debris will prolong the life of the parts.

De Jeeper

The flip side is that the screens reduce air flow. There r quantitative numbers out there. Also, the guys from Flat 6 dont recommend them. I dont really know which way is correct as there is issues with either the grills installed or not.

RSBro

I had not thought about that aspect, but you are right. From the Rennline website, they look to be pretty closely spaced to keep most debris out of there...

cds72911

Everything Rennline makes is nice, they do great work. I went DIY on my screens and have found them useful.

az968gpw

I have Rennline screens and like them. Seem to keep the stuff out. Have not experienced any overheating issues, but summer temps here rarely top 100; but i do drive down into the Phoenix inferno on occasion. Car runs normally around 180 degrees (I have the LN thermostat). Have a Flat 6 engine but I didn't talk to them before installing the screens. Probably could be an airflow issue but I didn't want to risk a radiator damage issue. So far no issues.

Dryslick13

Have them on my 01 C2 and have driven in temps at 100+ w/ no overheating. Does keep trash out.

dkraige

I've not found a reason to add them. After reading everybody else's tales of woe with stuff getting packed into the radiators, I use a shop vac every few months to suck out loose leaves that settle in there. People say that's not enough, so I finally took my bumper off after 3 years of ownership, separated the A/C condensers from the radiators, and cleaned it all real good. I say 3 years of ownership since that's all I can personally vouch for, but I'd assume this was the first time it's been thoroughly cleaned going back to 2001. I'd say there was in total about 1/4-1/2 cup of "junk" (dirt, leaves, cigarette butts, a scrap of paper, etc.) lodged into areas that can't be vacuumed out from the front. It was NOT an impressive amount of material, and I don't think cleaning it it out affected the car one bit. I'd estimate less than 5% of the radiator area was "clogged". It was all dry and there's no evidence of rot anywhere. So at least in my case, I'm happy to leave it alone, and I'll schedule my next bumper-off cleaning for about 15 years from now

If you aren't taking the bumper off, and you don't want to spend $300+, I'd leave it alone.
If you're going to be tracking/racing the car, I'd leave it alone as well, for the reasons others have stated that grilles will reduce airflow.
If you drive the car normally so airflow isn't critical, and you're already taking the bumper off for some other reason, and you want to spend a few hundred bucks, I don't think it would hurt anything to put them on there.

Rennline

Hey everyone! I just wanted to hop in and address the airflow question. We did some extensive summer track testing with the screens and we were not able to detect a difference in engine temperature. I will also mention that the GT4 and the GT3 come factory with grills screens. They also do a great job at keeping the rubber marbles out of your grills too!

Fracture

I have them on my AE, like the look a lot







I don't believe mine were ever cleaned in the previous 11 years, looks worse that it actually was

808Bill

I like them and think they're a great idea, but way over priced.
On the flip side, if JR say no, I'm going to listen to his advice.

TexSquirrel

I don't have them because Jake said to not use them.
If it were not for that fact, I'd have them on my car now.
But taking the bumper off every once in a while is not a difficult task at all.