I went down 1 tick mark on the temp gauge. I am still using the chity OEM gauge, but I will be installing new defi bf meter gauges soon and water temp will be one of them.

My car did like 20 dyno passes yesterday and my temps never went over 180 degrees. It was 89 degrees and 42% humidity.

 

Got more clarification about Koyo from my shop, they said the problem occurs when you overheat the engine, the radiator bulges out, but still functions. They said the problems they have seen this on have been the Z's with the Greddy TT on them. They said they have not seen the problem with the APS TT's, so - for the money it looks like I will go with Koyo.

 

The only problem with the Koyo is that some people say they need to cut the fans and shroud and others have said they didn't need to cut anything. If you have to cut your going to be charged at least 2 hours worth of labor. For that you might as well buy a direct drop in. Koyo $380 + $80*2= $540.....PE cost about that price and it drops in.

I think there might be two different koyo radiator that have different thickness and the smaller one might not need the cutting, but if you are going to upgrade the radiator why buy the smaller one? Something to think about. I personally might get a custom radiator that holds 7 gallons later in the future when I upgrade to the 700whp club.

 

We have the Koyo V-slims in stock. They are a slightly smaller core, but still twice as thick as stock. Fitment issues pretty much dissappear with this setup...its 36mm thick. I am installing this one on my super duty engine.

$375 shipped if anyone wants one. For the money, there is no better value out there.

 

Wow - 7 gallons - that is 58# just in coolant, not to count the radiator.

Here is another question, I see that Koyo make two different sizes, I was leaning towards the smaller since the larger I go, the more weight and the larger may start reducing air flow through the IC?

 

Read's Sharif's post above. I think that might be best for you.

 

I just installed the Koyo R2577 (The 53mm thick one) and I definately needed to trim a bit of the fan shroud near the AC lines. Only took a couple minutes to do though. The thinner Koyo would not need this trimming of the shroud.

 

You are correct...see my post above.

The 36mm requires no trimming, and the 53mm does require some trimming.

 

If I just upgrade the thermostat will there be a need to up grade the radiator? How much do the thermostats help compaired to the radiators?

 

Thanks for the info. I try to order all my parts from my shop, so sorry I will not be ordering this from you. If they can't get a part in the future, I may be calling you. I just like to keep the local guys employed.

 

Do you guys think this is REALLY necessary. I actually ordered a Koyo radiator and nismo thermostat, however, the koyo was damaged in shipping. So got me thinking.... do I REALLY need this? Perhaps I can use this money else where as both are NOT cheap... I don't track my car, so don't think this is something I really need. I told GRD to cancel my order for now since they normally stock it.... opinions??

 

Depending if you track it or if you live in a warm climate you will 1000% need one + an oil Cooler

 

If you don't track your car than your money would be better spent on adding an oil cooler. Yet, be careful adding an oil cooler if you plan on driving in the winter around Chicago. Do some research on how to properly add a oil cooler when you live in a climate that has many days below freezing.

 

Thanks for the tips guys, I think I will just go ahead and bite the bullet and purchase the upgraded radiator. I think the benefits outweigh the costs, especially with my built motor and daily driving.

 

My $.02 cents.

We have a radiator the quality and size of Stillen for the Z, and also build a custom radiator for the G35c. Makes a huge difference on keeping the cars from overheating.

Case in point, My Grey Big Horsepower G, I ran at 3 track events with heating issues just trying to push the stock radiator to its limits - FOUND... Then the next three, Willow springs, Streets of Willow, and Calspeedway, Upgraded to our new custom G35c radiator, and no heating issues.

NOTE: Here in SOCAL the track temps are constantly 90-100 degrees.

The radiator (and percentage of coolant to H2O) make a difference for sure. Don't forget the Oil cooler. Work.

Good-luck.

M

 

Upgrading the rad is definately a manditory item for tracked cars, or customer that drive like Gman.

I havent had one failure with a Koyo yet....its a great rad, and well priced. We always use the 36mm core, to avoid any potential fitment issues with various TT kits. Still trying to work on something for the TN kit.

 

Honestly, I don't even know where to start with how great the ARC radiator is. It is definitely pricey but I have found it to be worth every penny spent. I've tested it multiple times on the track, one being 120 degree track temperatures at Irwindale Speedway during two hard days of Forumla D. While every other competitor was sitting there opening their hoods and fanning their cars after each run, we just sat there with no cooling problems at all. The temp gauge rose just slightly one time, but that's about it. Note that I have an intercooler and compressor in front of my radiator with no other cooling parts (I know! Soon to come).
You will not be disappointed. ARC RADIATOR

 

So the 36mm will provide a substantial improvement in cooling over the stock rad.?

 

I am using the 36mm and have had no temp probs whatsoever. Fitment was perfect too.

 

Absolutely...its twice as thick as stock.