Over the winter I did some upgrades to my 355 SBC.
When I put it all together the rad had developed a leak.
The original specs on the car is 1983 Z28 camaro, LG4 305, had a 200c trans, and no computer ( built for Canada)
I call up my local parts dealer and ask for a rad for my car, and he asks if it's a 21 inch or 26 inch rad. I ask what the difference is, and he advised he didn't really know but the smaller 21 inch was alot more money.
I went with the 26 inch copper end tanks.
When I got it home I was surprised to find that my car from the factory with a LG4 had a small 21 inch rad installed in it. The original shroud even had the LG4 decals for emmission routing, and engine info (see pics)
I went to the wreckers and got the right top shroud and moved the rubber grommets over and everything else fit, tranny lines ect.....

So here is the question Anyone else had this issue?
Is the 21 inch reserved for the 4cyl cars?
I was thinking maybe when my car rolled down the assembly line they were out of 26inch rads so they threw in what they had?
When I swapped the 305 to the 355 I have now I thought I would upgrade the rad later so I never really paid attention. Last year in the summer heat I couldn't let her idle for more than 10 min standing still without over heating. At speed it was fine. Let me know if I'm alone on this one.
I can't find any info on this at all.

 

hmm i wonder if mines the same as yours with the 21 inch....

 

Have a look.....
Another interesting thing is there was no side panel to fill the gap on either side of the rad?

 

seen one of those on an '85 non-A/C lg4 z28-probably
found on all non-A/C lg4 '82-85 camaros,85 camaro
examined had same 7-blade clutch fan as other v8s,
but i did not look at the pulleys,often a smaller crank
pulley is used on non-A/C versions.

 

My car does not have A/C.... I have seen alot of cars in the wreckers with and without A/C and I have never sen a V8 car with the small rad like mine had. I did see a rare 4cyl car it had the small rad mounts but the rad itself was gone. I also saw a V6 car with the small rad as well.

 

I have seen quite a few V8 Cars in the wrecker yard none had a small rad except the 4cyl and a couple of v6 cars????? So is the small rad standard on all 82 to 85 LG4 Z28 non A/c Cars ? What do others have?
Since it was a car built for Canada maybe they figured it could get away with a smaller rad in the colder climate? LOL.....

 

Thinking back ,i do remember seeing non-A/C early
LG4s with the 26" radiator too,car was an'83 S/C,
had auto trans,'85 z28 i saw with the 21" was a stick
(did see your z28 is auto) '86 2.8 S/C (A/C automatic)
i examined had the 21"rad.

 

There really doesn't seem to be a reason one way or the other.......
I think they just threw what ever rad they had on hand into the car as it rolled down the line. The exception might be cars with A/C as they would need the bigger cooling
capacity. I just found it odd. When I did the switch, the rad hoses and tranny lines just had to be moved and tightened. No issues.......

 

My '84 T/A parts car is a LG4, 5-speed manual, non-A/C. I'll have to see what size radiator it has.

There was a "Heavy duty" cooling option, RPO V08. That might be the difference between the 21" and 26" radiators.

EDIT: The car has a 26" long radiator. The RPO SPID label is missing so I don't know if it has the HD cooling option.