Alrite heres what I got its an 87 rx7 with a chevy 350 and turbo 350 trans I understand these swaps tend to over heat but I know there has got to be a way to keep them cool motor is a 73 corvette block with 53cc heads new gaskets roller rockers cam etc. Aluminum rad its 22 long by 19 h. Has a 16 in electric fan pulling air threw rad and a 10 in in front of rad.im thinking I need a air dam in front has anyone been threw this with success its a real pain in the *** when your jst putting your foot in it and gota stop cuz its getting to hot

 

I dont have any problems over heating. Some blisters may be good to put on the hood.

 

We'll need more info, is it overheating when loaded or idling? is it overheating in stop and go traffic, intermediate speeds, or freeway? Is this ongoing or did recently start? What are you using for a temp gauge? Is the fan always on or is do you have a thermo switch? Are you sure the water pump was designed for the direction it's rotating (standard or reverse)?, is the ignition timing advancing properly?

If you're using the stock gauge it can very misleading, I was very concerned when my stock gauge went from the normal 1/4 to 1/2 on a hot sweltering day in stop and go traffic. I decided to see what it actually represented by hooking up a Sunpro temp gauge next to the stock gauge, unplugged the fan and let it run, here are the results for my FB https://www.rx7club.com/1st-generati...en-c-h-957956/

 

Well I know water pump is goin right way I checked that. It will over heat at idle but it does it gradually not quick like a head gasket and when I drive it it gets to about 210 and keeps climbing. Im using a aftermarket guage ive accually gone threw 3 of them because they got peged and there pretty much junk after that. O bought the motor for 100 bucks and put diff heads on it. Timeing is advanced properly. And fan is on all the time have a 16 inch and a 10 in front of rad. Rad. Is 22x19 tall kinda thinking I should go alil bit bigger for more fluid

 

A 22x19 should be all the radiator you need unless it's pencil thin, off the top of my head my guess would be an air pocket, crummy thermostat, or possibly a blockage. I would try a few random things if I were dealing with the same issue, first I would make absolutely sure the fan is pulling and not pushing (an easy mistake to make), then I'd try setting up a blower in front of the radiator, idle it and time how long it takes to get to a certain temp. If there are no changes I would also try either a different or no thermostat. Oh and one more thing, if all else fails, check to make sure the intake manifold gaskets weren't accidentally reversed since it's also an easy mistake to make during installation and would block flow the manifold and upper radiator hose.

 

With that size radiator you need to box the front of the core to catch as much air as possible, otherwise air will go around the radiator instead of through it. When I was running a 22x19 radiator I completely boxed the front of the radiator and had good results going down the highway but would still overheat easily sitting in traffic.



You need to run a water wetter also.

Another thing that will help is if you vent the hood in between the braces right above the strut towers. When running down the road the hot air will be sucked out of the engine bay. I experimented with this and saw some good drops in temp but I refuse to cut holes in my cowl hood until I find louvers I like enough to do it, so until then I'm just going to keep an eye on the temp gauge.

BTW I'm now running a 27x19 radiator with a Lincoln Mark VIII fan with decent results. It's fine going down the highway but I still have to watch the gauge.

 

What cfm are the fans you are running? Setup on my FD has one 11" ~1600cfm fan and one 11" ~2400cfm fan side by side,. both pulling through the rad. They are set up to come on in stages. For sure while idling it needs both fans on to prevent overheating, so ~4000cfm total. This might be overkill, as idling with the A/C on, the big fan will cycle on and off over time.

If you have one fan operating as a puller and one as a pusher, over the same area, I don't think there's any way you'd get the full benefit of both. Are they offset so that the one is pushing through one side of the rad and the other is pulling through the other side?

 

Ill hve to try the box in idea makes sence thnks for the pic gives me an idea to go by I hve a bunch of house fernace vent look jst like louvers tht I was thinkin about trying also. I hve a cowl hood doesnt seem to help much with the heat

 

im not sure of cfm I know there both good fans there not off set tho witch I can give tht a shot. Mite need bigger rad. For tht tho

 

What set up you hve for cooling?

 

I have a 347" motor with a turbo and no heat issues.

26x19x3" radiator with a Ford Taurus (early 90s 3.8L) fan. Works like a charm.

 

Wow wish I was in your shoes I accually have a fors taurus fan im gona try. What yrs ur rx7?

 

the stock radiator panel size in the RX7 actually is not that big when you consider it being for a V8. in that event you need a thicker radiator to compensate for the smaller radiator core size to start with.

scavenging a wrecking yard for a radiator that might fit won't work for this application. good ducting and a high CFM fan properly sized are next on the priority list, a single pusher with another puller fan will do almost nothing compared to a well fit/high CFM puller alone.

if you can't be bothered to pay for a good water temperature gauge then it makes me wonder how hacked together the cooling system really is. creativity is one thing but eventually you just have to buy proper parts/materials to make it work right.

 

I dont hve stock radiator its a ron davis 22x19x3 aluminum radiator and im useing a electronic temp guage

 

The chassis is an 88, but the body work is S5 (89+).

I have all the front metal between the frame rails removed and a custom tubular reinfocement and radiator/intercooler mounting system fabricated. The fan shroud on the Taurus setup is sealed to the radiator and the whole setup is fully ducted. I also run a 160* thermostat and electric water pump.

 

Well I have a Taurus radiator with a manual fan on front of the motor and an electric fan on front of the radiator to pull air in at idle. I also have a tunnel ram so a lot of heat natural escapes through the hood.