GTS346

iTrader: (1)

Have an aluminium old style SBC radiator here with the usual 1 3/4" outlet and 1 1/2" inlet.
Noticed the LS1 has smaller necks, is the thermo neck 1 1/2" and the pump outlet 1 1/4"?

Do most you guys just run the smaller hose and stretch them over the larger radiaotr in/outlets?

G-Body

iTrader: (4)

I put an 2001 Tahoe 5.3L in my 85 El Camino with the old copper/brass radiator. I never measured the outlets but the hoses fit just fine. I used the radiator hoses from the tahoe and they fit the radiator just fine. Mabey the truck hoses would work well for you too.

ls1canuck

I used 2 brass reducers that I got from a rad shop. One to go from 1 3/4" to 1 1/2", and one 1 1/2' to 1 1/4", then used a 2005 tahoe upper hose to go from the motor to just before the rad, put in the reducer, then used a short piece from the reducer to the rad. For the bottom hose I just put together some scrap pieces I had laying around, One that was 1 1/2" and one that was 1 1/4" with the ruducer in the middle.

However I think the best solution is to take the rad into the shop and have the right size inlet and outlet welded on to it so that it matches the motor. You won't be able to strech a smaller hose onto the bigger outlet or inlet pipe. I would have definately done it this way except that my rad is aluminum, and I had trouble finding someone who would weld it.

GTS346

iTrader: (1)

You reckon I cant stretch it 1/4", arrrrrr was hoping so.

LS1Cobra

I have the same problem as you are. I got the electric water pump and the outlet can only fit the 1 1/4" fitting. If I put the 1 1/2" fitting on there is no room to put the hose on because the fitting will be sitting too close to the electric motor. I am still searching for the reducer at the moment. Let me know if you find any. Thanks

sparkwirez06

iTrader: (18)

the top and bottom rad hoses are 1and5/16ths, thanks

GTS346

iTrader: (1)

Ok I managed to get a 1 1/4" hose on the top (rad is 1 1/2") squeezes on fine and doesnt buldge.

For the bottom hose I am going to weld a sleeve over the thermostat so it will accept a 1 3/4" hose.

It looks like the top is 1 1/4" and the bottom (thermostat) is 1 1/2"

digitalsolo

iTrader: (24)

I just use the Napa universal hoses. They have a spring inside to prevent kinking and they come in 10-12 different lengths, with just about any size you need on either end.

Something like 10 bucks each too. Worked great for my swap.

Pro Stock John

iTrader: (34)

I've been wondering this for a while, the LS stuff is 1.25 upper and 1.50 lower, and I think SBC stuff is 1.50 upper and 1.75 lower. Does Napa really make hoses with different dimensions on each side?

Build-it-Break-it

iTrader: (9)

http://www.jagsthatrun.com/Pages/Par...eSplicers.html affordable and simple solution

Pro Stock John

iTrader: (34)

Awesome, I feel less mental now.

TXsilverado

iTrader: (18)

just wanted to say thanks for the link! exactly what i was looking for and i didnt know what i was looking for

ls1nova71

iTrader: (4)

Or you can run the larger hose and reduce it down at the engine with this.

04Z06vette

there are a ton of hoses that have different sizes on each end. I found a link somewhere to a Gates product catalog that listed every hose they made at the time with the dimensions and a pic of the shape. it is sorted by end size and length, so you can just jump to the section with your end size and then look for one about the right shape. It worked for me. I don't have the link any more, but I can send you the file if you PM me your email. it is like 8M, so cant post here.

TXsilverado

iTrader: (18)

easier to throw in a metal reducer....this is going in a 69 Camaro so nothing is straight forward. it had similar reducers as posted above, and they leak slowly...I can get a good clamp down on a chunk of aluminum.