SirRobyn0
Full Access Member
- Joined
- Dec 6, 2019
- Posts
- 6,755
- Reaction score
- 11,402
- Location
- In the woods in Western Washington
- First Name
- Rob
- Truck Year
- 1984
- Truck Model
- C20
- Engine Size
- 305
Ok so in another thread I made the decision to install a Spectra CU730 in my truck. My truck C20 305 / 700R4, primary uses are DD, hauling and towing 18' open trailer for the farm. Original radiator was copper / brass 3 row 19" tall radiator. I wanted maximum cooling so after deciding the cost of going all aluminum was not going to work out, I went with the Spectra CU730, this radiator is the stock equivalent for 454 W/AC & Max cooling. So it's a very wide 2 core equivalent to at least a 4 core, the 730's core is 2 1/2" wide!!! If you search this site, or the web, you'll find that plenty of guys swap this radiator into their small block trucks as an economical upgrade. I would have actually preferred to keep the cooper / brass but it wasn't practical.
So before deciding to install a 1 1/2" taller, and wider core larger tanked radiator I did some research ahead of time. Most guys seemed to have problems with the mounts, not the metal part but the rubber part as the 2 and 3 row rubbers are to small. So I ordered a set off rubbers for the CU730, so I wouldn't have to modify mine.
My experience. The radiator fits, but it was a much more tricky and required more modification to install than I had expected. First issue I ran into. I was doing the install on the farm, and I'd left my new rubber inserts for the mounts at the shop I manage in town. Driving the 2 hours there and back wasn't practical, so as a stop gap I cut 2 pieces of heater hoses to the length I needed and then cut them in half length wise. That will work for now, but during the work week at the shop I'll pull the top mounts out and slide the proper rubber inserts into place, so that issue is my fault completely and will be remedied shortly. Next issue, the shroud won't fit over the top of the radiator. I know I should have seen that coming, but the most I'd seen was one guy said he "had to trim the shroud a bit, no big deal". Well it's more like you have to cut the entire top of the part of the shroud off that laps over the top of the radiator. I can do that and if done so it's clean and looks good that's fine with me, but I didn't really bring anything from the shop to do that.... So I cut most of the top of the shroud off by scoring it with a razor knife and snapping it, then I took a couple feet of rubber fuel line and slit it length wise and put it along my cut. It looks okish, probably a lot of people would be just fine with it as is. I left a little bit more of the plastic shroud top on purpose so when I'm at work I can cut it and shape it with my angle grinder and / or dremel to look nice and smooth and good. Once the trimming is done the shroud will fully bolt up and sit just like it did before, so this doesn't change the shroud to fan spacing in anyway, so all that should work fine.
Hoses, transmission cooler lines. All that stuff lined up and went together just fine. One more thing then pictures. My old radiator only held about 1 1/4 gallons of coolant, I knew that it had some calcification so I knew it probably wasn't holding as much as it should. The CU730 I just installed took about 3 1/2 gallons of coolant, so it's compacity is definitely much larger.
Pics!
Below: installed and filled!
Below picture doesn't really show it, but it does clear the core support without touching, it's a small amount of clearance but should be fine as long as the radiator stays tight, which should not be a problem especially after I get the new rubber mount inserts installed.
Below: Top of the shroud. I'm almost a little embarrassed to post this picture, as I thought it looked tacky at the time, but in looking at the picture it's not to bad and will be even better after I trim it properly at work. Will have to be careful not to burn my hands it though! If you look on the right side of the picture see the screw clamp on the A/C line. The truck has had a long standing issue of needed to be recharged each spring. After moving the line around it started hissing there, so I though that clamp on it. Well I guess to good news there is I found that slow leak. So I'll need to replace it this spring.
Below, my flavor of choice for Antifreeze, ACDelco classic green. It's available to me though a wholesale supplier (WorldPac) for a really good price $10.50 a gallon. Well that's a very good price around here anyway. plus it's ACDelco! What's better than filling a new radiator in square if ACDelco coolant!
I wasn't having any overheating issues, but still I'm looking forward to driving it tomorrow to see if I notice any changes.
So before deciding to install a 1 1/2" taller, and wider core larger tanked radiator I did some research ahead of time. Most guys seemed to have problems with the mounts, not the metal part but the rubber part as the 2 and 3 row rubbers are to small. So I ordered a set off rubbers for the CU730, so I wouldn't have to modify mine.
My experience. The radiator fits, but it was a much more tricky and required more modification to install than I had expected. First issue I ran into. I was doing the install on the farm, and I'd left my new rubber inserts for the mounts at the shop I manage in town. Driving the 2 hours there and back wasn't practical, so as a stop gap I cut 2 pieces of heater hoses to the length I needed and then cut them in half length wise. That will work for now, but during the work week at the shop I'll pull the top mounts out and slide the proper rubber inserts into place, so that issue is my fault completely and will be remedied shortly. Next issue, the shroud won't fit over the top of the radiator. I know I should have seen that coming, but the most I'd seen was one guy said he "had to trim the shroud a bit, no big deal". Well it's more like you have to cut the entire top of the part of the shroud off that laps over the top of the radiator. I can do that and if done so it's clean and looks good that's fine with me, but I didn't really bring anything from the shop to do that.... So I cut most of the top of the shroud off by scoring it with a razor knife and snapping it, then I took a couple feet of rubber fuel line and slit it length wise and put it along my cut. It looks okish, probably a lot of people would be just fine with it as is. I left a little bit more of the plastic shroud top on purpose so when I'm at work I can cut it and shape it with my angle grinder and / or dremel to look nice and smooth and good. Once the trimming is done the shroud will fully bolt up and sit just like it did before, so this doesn't change the shroud to fan spacing in anyway, so all that should work fine.
Hoses, transmission cooler lines. All that stuff lined up and went together just fine. One more thing then pictures. My old radiator only held about 1 1/4 gallons of coolant, I knew that it had some calcification so I knew it probably wasn't holding as much as it should. The CU730 I just installed took about 3 1/2 gallons of coolant, so it's compacity is definitely much larger.
Pics!
Below: installed and filled!
You must be registered for see images attach
Below picture doesn't really show it, but it does clear the core support without touching, it's a small amount of clearance but should be fine as long as the radiator stays tight, which should not be a problem especially after I get the new rubber mount inserts installed.
You must be registered for see images attach
Below: Top of the shroud. I'm almost a little embarrassed to post this picture, as I thought it looked tacky at the time, but in looking at the picture it's not to bad and will be even better after I trim it properly at work. Will have to be careful not to burn my hands it though! If you look on the right side of the picture see the screw clamp on the A/C line. The truck has had a long standing issue of needed to be recharged each spring. After moving the line around it started hissing there, so I though that clamp on it. Well I guess to good news there is I found that slow leak. So I'll need to replace it this spring.
You must be registered for see images attach
Below, my flavor of choice for Antifreeze, ACDelco classic green. It's available to me though a wholesale supplier (WorldPac) for a really good price $10.50 a gallon. Well that's a very good price around here anyway. plus it's ACDelco! What's better than filling a new radiator in square if ACDelco coolant!
You must be registered for see images attach
I wasn't having any overheating issues, but still I'm looking forward to driving it tomorrow to see if I notice any changes.
