radiator selection

[kev2809]

what are you guys doing for radiators with an ls swap? i bought this one i planned to run woth my old 305, but not sure it will work with the new motor. hell, i dont even know if it wouldve worked with the 305, never seen the road long enough lol.

id like to continue to use this, ut if not i will have to be on the search for a replacement.

[truckdude239]

i bought an all alumin one from cold case with fans

[LS short box]

I like dual pass radiators on LS swaps. The inlet and outlet are on the passenger side of the radiator. Makes coolant hose routing much cleaner. My 68 has Afco dual pass universal fit. I modded the upper and lower stock mounts to work with the Afco radiator.
See attached pic.

[kipps]

kev2809, what truck are you working with?

The squarebody radiators are frequently used in LS swapped squarebody trucks. The inlet and outlet ports are in the correct location and are the correct diameter for stock LS hoses.

Depending on what mounts you use, the LS mechanical cooling fan might or might not align correctly with the fan shroud.

[kev2809]

probably shouldve put truck info in the first post...

67 suburban. i bought this radiator from a friend a while back. he usually only buys or builds 90s model silverados. im assuming that was the intention for this radiator.

im hoping it will work to keep my costs down. is there any other measurements needed?

[kipps]

If you can physically mount it to the core support, and if you're willing to run electric fans, it will be fine.

If you want to run a mechanical fan, you'd better stick with a radiator and fan shroud setup from 1967. Pair that with a set of LS 67-72 mounts that put the LS engine in the same place as a SBC, and the fan "should" line up.

[kev2809]

Originally Posted by kipps

If you can physically mount it to the core support, and if you're willing to run electric fans, it will be fine.

If you want to run a mechanical fan, you'd better stick with a radiator and fan shroud setup from 1967. Pair that with a set of LS 67-72 mounts that put the LS engine in the same place as a SBC, and the fan "should" line up.

it mounts just fine, i would just need to section the top rad mounts to make it fit snug. i already bought the dirty dingo slider mounts so i can slide the motor up if need be. i havent decided if i will run the stock mechanical fan or electric fans just yet, havent researched what you guys are using for these swaps. i know stock, these ls fans sit about half way in the shrouds.

[mongocanfly]

I'm running the stock radiator that was in front of my 350...never had a issue with overheating..normally runs around 175-180 ....it does have dual electric fans though..

[ls1nova71]

I always use mechanical fans whenever possible, but a lot of people just have to have electric fans for some reason. Once you have an electric fan burn up 1000 miles from home, you change your opinion of them though. LOL!

[kipps]

Originally Posted by ls1nova71

I always use mechanical fans whenever possible, but a lot of people just have to have electric fans for some reason. Once you have an electric fan burn up 1000 miles from home, you change your opinion of them though. LOL!

As I see it, the electric fans come in pairs for a reason. One fan should be enough to get you through slow traffic. You don't need any fans for highway cruising.

I'm installing electric fans. My reasoning, is 95% of my driving is short 1-mile trips, or highway-speed cruising. I won't need fans in either scenario. With electric fans, they'll mostly just sit there unused. I'm very rarely driving in stop-n-go traffic, and I'm not installing air conditioning. My engine mounts will allow for a mechanical fan though, so if I have problems, I could easily swap it out.

[LS short box]

Kind of disagree on the electric fan statement. You would be hard pressed to find a mechanical fan on a current daily driver. Anything with AC will have either two fans or a single two speed fan.
The key to making a electric fan live a long life is good wiring and quality relays. Also a quality fan maker. I always buy Spal fans. Never had a failure.
Just got done plowing the driveway with my 98 Wrangler with a LS6 swap. Did the swap 12 years ago? and the fan is still working like a champ.
If you think you might have a failure buy an extra fan assembly and keep it in the car/truck. I do that with the 255 fuel pump and never had to use it.
Just my.02.

[ls1nova71]

Originally Posted by LS short box

Kind of disagree on the electric fan statement. You would be hard pressed to find a mechanical fan on a current daily driver. Anything with AC will have either two fans or a single two speed fan.
The key to making a electric fan live a long life is good wiring and quality relays. Also a quality fan maker. I always buy Spal fans. Never had a failure.
Just got done plowing the driveway with my 98 Wrangler with a LS6 swap. Did the swap 12 years ago? and the fan is still working like a champ.
If you think you might have a failure buy an extra fan assembly and keep it in the car/truck. I do that with the 255 fuel pump and never had to use it.
Just my.02.

I'm not here to argue which one is better, but every Chevy truck with an LS engine up to 06 or so only had one engine driven clutch fan, and they all had A/C, and all worked fine. The main reason. They don't use them anymore isnt because an electric fan is any better, its for fuel economy, plain and simple. Its not even a noticeable amount either. I was just stating that a clutch fan won't burn out on you in the middle of nowhere like an electric fan can. Not saying it will. I too carry a spare fuel pump, but in the car I drive the most, there's not a lot of room to be hauling around a lot of spare parts. The fans I use are quality parts, but I have 100k plus miles on my swaps, and things don't last forever.

[skyphix]

Originally Posted by ls1nova71

I'm not here to argue which one is better, but every Chevy truck with an LS engine up to 06 or so only had one engine driven clutch fan, and they all had A/C, and all worked fine. The main reason. They don't use them anymore isnt because an electric fan is any better, its for fuel economy, plain and simple. Its not even a noticeable amount either. I was just stating that a clutch fan won't burn out on you in the middle of nowhere like an electric fan can. Not saying it will. I too carry a spare fuel pump, but in the car I drive the most, there's not a lot of room to be hauling around a lot of spare parts. The fans I use are quality parts, but I have 100k plus miles on my swaps, and things don't last forever.

I think both are viable options, but twice I have lost a fan clutch in the middle of no-where and had to drive home with the heat on in the middle of summer trying to keep the temp below nuclear temps.

Ultimately, I have no issue using either. Parts fail. I've had 200+k mile electric fans (the ones in my squarebody, for instance) that have lived a harsh life of all dusty/unpaved roads, and I have had 200+k mile clutch fans. I've also had both systems fail at about the same rate. Both do the job intended.

For the original poster, I'm using a 2006 GMC Yukon 34" core radiator with the surge tank and the dual fan setup out of that same Yukon. I've only got one wired in right now and it keeps the truck plenty cool enough. The radiator you posted looks like it will physically work.

[nsb29]

My 2 cents is whether it is an electric fan, fuel pump or whatever if it’s a vehicle that you Drive on a regular basis and put miles on use parts that can be readily available at a local parts store. I have electric fans because of engine position as well as the engine coming from a car was not set up for mechanical

[kipps]

Originally Posted by nsb29

My 2 cents is whether it is an electric fan, fuel pump or whatever if it’s a vehicle that you Drive on a regular basis and put miles on use parts that can be readily available at a local parts store. I have electric fans because of engine position as well as the engine coming from a car was not set up for mechanical

That's a key tenet of of my build. I don't want to have to wait more than 12 hours for any individual part to show up if needed.

[mongocanfly]

My reason for using electric fans is due to the mech fan not lining up with the radiator or the shroud...the top of the mech fan was close to the center of the radiator..

[kipps]

Originally Posted by mongocanfly

My reason for using electric fans is due to the mech fan not lining up with the radiator or the shroud...the top of the mech fan was close to the center of the radiator..

Which truck was this? I figured at least your squarebody truck would have been pretty close to correct.

[kev2809]

this truck will not be daily driven at all, just a weekend cruiser. well, i do have the whole donor truck so i could use the 01 yukon radiator if i need too, but i believe the current one i have will give me a lot more space if i run a mech fan....plus i could sell that stock one off the donor. i will have my current one taken to my.local rad shop and have em flush it and pressure test it to make sure its good to go.

one question though, i read a lot about these swaps and people mention they have a steam line welded in for the ls. what the hell is that?

[ls1nova71]

The steam line in the radiator hooks to the steam lines that are bolted to the front of the heads. Some people tap the water pump and hook it to that, some people cap them off and say they don't have a problem, but GM put them there for a reason, to get all the air out of the system to keep from creating hot spots in the head is what I'm told.

[Justin71105]

Lookong for a radiator for my LS swapped 64 atm. Been eyeing this one, all I need is a fan relay setup and would be in business. I like that it has built in trans cooler as well.

https://www.universalpartsinc.com/sh...?i=1117308&c=0

[kev2809]

Originally Posted by Justin71105

Lookong for a radiator for my LS swapped 64 atm. Been eyeing this one, all I need is a fan relay setup and would be in business. I like that it has built in trans cooler as well.

https://www.universalpartsinc.com/sh...?i=1117308&c=0

thats a very nice setup, but too rich for my blood. im trying to keep this on a budget lol. but considering the spal dual 11 inch fans with the plastic housing runs about 350 plus, that 600 for all aluminum is nice

Originally Posted by ls1nova71

The steam line in the radiator hooks to the steam lines that are bolted to the front of the heads. Some people tap the water pump and hook it to that, some people cap them off and say they don't have a problem, but GM put them there for a reason, to get all the air out of the system to keep from creating hot spots in the head is what I'm told.

ill have to read more into that. so if there isnt a steam port welded into the radiator, the only option is to cap them or tap the water pump?

[kipps]

Originally Posted by kev2809

I'll have to read more into that. so if there isnt a steam port welded into the radiator, the only option is to cap them or tap the water pump?

There's also the option of using this.

https://jagsthatrun.com/products/fix...v8-engine-swap

I wouldn't expect to get much resale value out of a used radiator. They're cheap enough new, that most folks don't even bother to check marketplace before just buying a new one.

At least mock up the 2001 radiator, shroud, surge tank, and mechanical fan, and see if they could be made to fit. That would definitely be the way to go if you can get the components to fit in nicely. The challenge will be getting the engine to sit in the same relative position to the radiator as it was in the original donor vehicle. This is so the fan and the shroud align correctly.

[mongocanfly]

Kipps... the IH was way off...not even close to center...the C30 wasnt as bad but it didnt line up in the factory shroud..

[kipps]

I pulled and reinstalled two transmissions on these classic trucks. Both were manual. A 1987 chevy 4wd, and a 1981 Ford 2wd. The chevy was missing the extra brace pieces that went to the top flange on the frame rail. I didn't worry about it. The Ford had those braces, but I don't remember if I bothered to reinstall them or not.

Just drill new holes in the bottom frame flange, and call it good. It's not worth the trouble attaching it to the top flange, in my opinion.

As far as rivets vs bolts, it'd be REALLY unhandy to do a clutch job without removing the crossmember. Probably impossible on some transmissions. If there's rivets there, cut them off, and replace with bolts.

[ls1nova71]

I should have been more specific, the crossmembers are riveted in on manual transmission equipped Chevy and GMC trucks from 67-72. I suspect they stopped doing that in 1973 when the body style changed.