pugwash

How on earth do i work out what the minimum size rad i need is?

the LS1 is going in an offroad buggy which wil be working hard at low speeds and the rad "may" get gunked up with crud.

Summit lists literally hundreds of Ali and non ali rads, but i have way of choosing. They are all listed by size- is there a guide to radiator choice that anyone knows of? i have looked all over the place but can't find anything that might help me.

I can't really afford to get the selection wrong as some of the car is being built around the shape and size of the rad!

Thanks

Jim

Rodder

iTrader: (2)

I'm not a offroad person, but seems for low speed crawling, you would go with the biggest you can so that if it gets partially clogged with mud, you have a better chance of not overheating. There's a probably a limit of how wide you can reasonably build your chassis--that'll determine how big of a radiator you have room for. On the other hand, there are lots of LSX motor running around behind wimpy little Jeep Wrangler radiators, so anything you choose within will probably work fine (until it gets clogged with mud). Whatever radiator you end up with, you'll want to build a custom shroud to mount your electric fans so that they pull over the entire surface of the radiator.

Novas Forever

LSx's are pretty easy to cool. Hot Rod had a test on the Summit aluminum radiators and they did good, on the street. That is what I bought.

bczee

iTrader: (12)

I would suggest you just use the same method of picking a radiator as you normally would. Many of the new Radiator with there new 1" tube and duel pass setup will just add to the cooling. Good Fans are a must.

IMO, would recommend what the biggest size you can get in there, but use one of cross flow with two (or three) 1" tube setup. A Duel pass setup would also work out to your advantage. Aslo adding a single or duel fan setup would be my suggestion also. With the slow engine speed, it is just important to keep a good air flow going and block as much crud as you can. I use one of them bug screen and shake it every once in a while to clean it off. I would also recommend if you have a Auto trans, is to use a seperate cooler (with fan) and not have one in the radiator.

With the slower engine speed of crawing, you don't have the higher temp problems that a high RPM engine would generate. If you over heating at low speed, you have other problem than just the size of the radiator.

I have had my 4x4 Van for many years in the Sierra/Tahoe area and tho I can't go where the hard core rock crawer go.. I have been many places where I have freaked them out as I come through with a Full Size SWB G30 VAN.. for Slow moving a good cooling is a must, my VAN just had a good HD radiator and flex fan setup and with the engine very well covered in the VAN, I have never had a problem of over heating in 80-90 degree weather.

pugwash

thansk for the quick replies.

Novas - can you remember what size rad you bought?

i do currently have a rad that is from a Rover 4.6 V8 (basically a Buick 300 engine- yeah THAT old), and this thing kicks out a LOAD of heat because the engine is so inefficient.

but is there any way of finding out if the LS1 kicks out more heat than the 4.6?

bczee

iTrader: (12)

when you say LS1.. are you talking a real LS1 with a alum block and head or a LSx / Gen III/IV with a iron block / alum head engine ?

many refer to any Gen III/IV engine as a LS1 (engine code).

Novas Forever

I had to contend with the size of the opening in the radiator core but I got the one that is 1 step up from the smallest size in the catalog. A good fan is very important but can be had for a good price. The 2 speed version out of a 3.8 Taurus or Lincoln is cheap and good.

pugwash

interesting about the engine code

i thought LS1s were only ali blocks. Anyway it's definintely an ali block- i'd never be able to move an iron block- and it came from an '02 GTO so if it's not an ali block then i've been diddled.

bczee

iTrader: (12)

Well, GTO didn't get marketed until 2004 here in the US...... so as far as your engine being a LS1 out of a 02' GTO... not much chance...

Here is some information on GM Gen III and IV engines. This will help you to find out what engine you have and its correct engine code..
It is starting turn into a problem of the name "LS1" being used as a commond name for all Gen III and IV engines. Another more common and correct name is sometime used as "LSx", but Gen III or Gen IV would be the correct term for the class of engines, depending which one you have.

my 2 cents...

Sorry, forgot the link..
http://en.wikipedia.org/wiki/GM_Vortec_engine

look under the Gen III and Iv sections..

CharlieLed

iTrader: (1)

I live in San Diego and there are quite a few LS powered buggies around here. I used to be into dune buggies but got out of the sport prior to the advent of the water cooled engines so I don't have a lot of current info. If you would like to send me a PM or email letting me know that you're interested, I can follow up with some of the shops I know here in town and get some more data for you.