I AM CURRENTLY IN THE PROCESS OF BULIDING/INSTALLING A 383 STROKER(BORED .040 ACTUALLY 385) INTO MY 91 FIREBIRD THAT WAS ORIGINALLY EQUIPPED WITH A 305. I WAS WONDERING IF ANYONE OUT THERE HAS ANY EXPERIENCE WITH ANY SPECIAL COOLING NEEDS WHEN RUNNING THESE LARGER DISPLACEMENT MOTORS???

THANKS FOR THE HELP FOLKS ,
JOSH

 

Turn off caps locks, it's rather annoying to read. Thank you.

They cool pretty much the same way a 350 does. It's also nearly impossibe to predict the cooling needs of any engine. I've seen a stock radiator cool down a 480 horse/6500 rpm 400 small block, and I've seen a factory radiator NOT abe to cool a stock 200 horse 350. It depends too much on the running factors of the engin (compression, A/F ratio, RPM's, etc). My advice would be run the engine and see what temperature it runs at and see what you need thereafter.

If anything to start out with, upgrade to a high flow water pump, such as the ones offered by Edelbrock, Weiand, or Stewart. Another thing to add to the probable upgrade list would be a good fan that draws a decent amount of air over the radiator.

After that, run the engine and see what temperature it runs at. Make decisions after that.

 

I did the same jump. That is 1991 firebird with 305 TPI to 406 motor. I am not sure if the stock equipment would have worked or not (probably would have). But I went with a BeCool Aluminum radiator, Stewart Stage 3 reverse flow pump, 160 thermostat and Evans coolant.

The Evans was needed because of the compression of the motor. Also have aluminum heads to help with the cooling.

383 is not as bad as having a stock production block 400. I have the Bowtie block so wasn't an issue for me.

 

I have an 87 that is running the stock cooling system from the 305 TPI, it cools my 383 TPI no problem. If I run it around at 3500 rpm all over town it can get a little warm, but as long as your not running a real high stall torque converter your rpms wont need to be very high.

 

i have a 383 set up in my 85 TA i installed a griffin 31/19 rad from summit a dual fan set up from a 4th gen camaro with a milodon high flow water pump and i dont ever have any cooling issues. by the way i live in new mexico so it gets over a 100 in the summer on a reg basis. good luck.

 

How does that griffin radiator fit? Any mod's needed??

 

Griffin makes one specifically designed to fit our cars. I bought it and had to return it because it fit like poo. I bought the BeCool one instead. I have heard though the the universal fit Griffins do work with a little creativity.

 

Had a Griffin direct fit put in my car. Per my mechanic it was no were close to a direct fit. The fittings are in the same locations but it is much thicker.
He had to do a bit of fabrication.

However, it does keep the car cool

 

I bought the 31x19 griffin the universal 1 with no extra tranny line holes. i ended up using the factory lower rad hose and then modifing a 77 k5 blazer upper hose. the upper support i used looks like a 76-77 malibu support. I used the stock rubber for the cushion. my set up works very well. By the way the be cool rad is very expensive so the extra work was worth it.

 

got any pix of the setup?? Just curious as I don't have much room between the procharger pulley the existing upper rad hose....

 

[QUOTE=5.7iroc-02ws6]got any pix of the setup?? Just curious as I don't have much room between the procharger pulley the existing upper rad hose....[/QUOTE
unfortunatly i dont have any close up pics. I currently have my set-up torn apart for some engine work. By looking at your pic in your sig i would think that there is not enough room to duplicate my set-up. It looks like you have a sandard upper rad hose so it is possible. you def will not be able to use a blazer hose like i did because the procharger and bracket are in the way. the radiator fans and support might work though.

 

I run the stock rad with a iron headed, 10.4:1 383 and don't have any cooling problems at all. Driving around 160, never peaks over 180. i put in another elec. fan switch though to turn on at 185 instead of the factory 215, which is a must in my opinion.

 

I have a stock radiator (brand new when the motor went in) and my 383 never gets over 180 degrees.I have an 84 Trans Am with the Trans Am grilles which give absolutely no air flow to the radiator and I have never over heated once.VERY IMPORTANT THOUGH: be sure to have a good front spoiler or air dam under the front of the car, if not then you could def overheat, this I have seen personally, so if you don't have one or don't have a good one then replace it.

 

I run a 383 in south Florida and I have a friend that runs a 383 as well. We both can offer the following:

Using the stock aluminim radiator or a 3 core brass radiator with the factory twin third-gen cooling fans will work...marginally in south Florida. That is without the a/c on and not sitting in stop/go traffic.

If you need a/c, the temp will average around 220 on the highway and scare you to death in traffic. If you are in stop-go traffic with the a/c off, the temp will slowly creep up into the 220's but wil drop as soon as the car can move and get some air through it.

I like to be as worry free as possible, so I swapped out to the Northern radiator with twin 1" rows. Tight fit, aggrevating to install...but worth the peace of mind.

I tend to think that part of the answer to this question is in what climate you drive the car. In any case... proceed with caution with whatever you choose. It may take you some time to sort it all out. Good luck.