(Radiator) Drag guys, who drive occasionally on the street...

[Okibonoe]

What is the smallest, lightest radiator you can get away with? We are talking about a E85, 40+psi, 750+ to the wheels combo. Thanks!

 

[b00stedtalon2]

I have a tiny KLM radiator with a built in shroud and small SPAL fan. I drove the car for one hour in 80*F and didn't have any issues until I got stuck in bumper to bumper traffic for 25 minutes.

You must be logged in to view this image or video.

 

[Okibonoe]

Thats nice! Thats exactly what im looking for.

I have a tiny KLM radiator with a built in shroud and small SPAL fan. I drove the car for one hour in 80*F and didn't have any issues until I got stuck in bumper to bumper traffic for 25 minutes.

You must be logged in to view this image or video.

 

[Archer Fabrications]

I have an STM koyo core half rad for sale in the classifieds bolts in using oem mounting

 

[Okibonoe]

I have an STM koyo core half rad for sale in the classifieds bolts in using oem mounting

Cant find it, do you have a link?

 

[OH91awd]

another option would be a sirocco style radiator. thats what i run on my car.

 

[motomattx]

I run the Sirocco radiator myself also, and even with it, the car will get well over the half way mark in sit still traffic where theres 25 min of sitting when its 90-100 degrees out, (I dont have much room for fans only small ones) I wouldnt want to run anything less.

 

[OH91awd]

I run the Sirocco radiator myself also, and even with it, the car will get well over the half way mark in sit still traffic where theres 25 min of sitting when its 90-100 degrees out, (I dont have much room for fans only small ones) I wouldnt want to run anything less.

with mine it never got over 205* with a 180 tstat. and that was in town street driving middle of summer in ohio. i also have a derale fan that moves 1500cfm of air (it was the biggest i could find that fit between the compressor housing and the rad).

 

[ThunderChild]

This is pure speculation from me, but I've always wondered if the rad isn't the main issue, and the water pump ports on the block are.

Case in point, Mazda 1.6-1.8 blocks. I have had a couple and run some small size rads, namely Honda rads, and never had issues overheating or even getting remotely warm.
The water pump impeller sits essentially inside the block with no shrouding, it's one ~3" hole that's directly in the water jackets. I've contemplated opening up the holes in a 4g block and swapping the impeller or at least using an anti-cavitation style impeller to improve the ease of flow without increasing pressure or drastically changing other aspects.

The pump entry ports on the blocks are vastly different, but otherwise the engines coolant path is fairly similar, pics for reference.

Mazda block, HUGE pump port opening and open to both sides of the cylinder walls.

You must be logged in to view this image or video.

4g block we all know and love, I realize this ones filled but you can see the comparison or port sizes.

You must be logged in to view this image or video.

Pics were just Google grabs, not my own and I take no credit for them.

 

[motomattx]

Your only going to flow what is limited by the inside diameter of the coolant hoses, that 3" hole wont flow a lot more than the Mitsubishi holes and it leaves a weak spot in the block.

 

[Okibonoe]

Good stuff yall

 

[diambo4life]

I run the Sirocco radiator myself also, and even with it, the car will get well over the half way mark in sit still traffic where theres 25 min of sitting when its 90-100 degrees out, (I dont have much room for fans only small ones) I wouldnt want to run anything less.

I think your issue here is your fan or fans. I run an AFCO in my Galant and even in standing traffic with 100 deg temperatures outside, it rarely goes over 200degF. I have a single beefy 11" SPAL fan on mine.

 

[motomattx]

Oh its likely my fans yes, I simply dont have room for any larger fan and the best I can do is run a pusher on the front of the radiator at that, and a tiny 6" or so puller on the engine side off of a Yamaha raptor.

 

[jed344]

Full wet or 1/2 filled block? I can tell you my 1/2 filled block running on e85 stays very cool coolant temp wise. Oil temps can be a different story, I assume because now there is less cooling load on coolant and more on the oil.