I'm not a member there and it let me at least read the post.....but....now you can read it here.
"As some of you know my Project Car aka the Black Pig was recently completed and i am in the tuning de-bugging stage. I was having some serious heat issues and tried a bunch of things to help cool it down. It has plenty of cooling capacity with a new dual pass aluminum rad so i was pretty sure that wasn't the issue.
The one thing that struck me as odd was the amount of radiant heat coming off the top of the engine....there was a ton of it. I've been around and tuned enough 440's to know that this wasn't normal. I started by replacing the 2000cfm pusher fan with a 3000cfm puller and that seemed to help somewhat but there was still lots of heat on the top end. I suspected the thermostat so i swapped in another one with basicly no change. I verified that both stats were functioning by testing them in boiling water and verified the open temps with my infrared heat gun...both worked fine.
Basicly, it would idle at 190* but out on the road the temps would spike and bounce between 180* and 210* almost instantaneously....like over a 5 second time frame. Normally when engine temps spike out on the road it's an airflow/obstruction issue with the radiator but this was different. I finally reasoned that there was an air/steam pocket in the cooling system and as that pocket moved around and the hot steam hit the water temp sensors it was creating the spiked temps. This made sense and explained why the guages were reading the way they were but didn't explain why the air pockets were forming despite repeated attempts to purge the cooling system. The fact that the top end of the engine was so hot was a clue and i figured that the coolant wasn't being circulated fast enough so it was boiling inside the engine creating the air pockets....but why was this happening ? scratchchin
So, i'm on the phone discussing this problem with Dwayne @ Porter Racing heads and he's asking the usual questions :
(1) enough rad....yep, dual pass aluminum
(2) thermostat defective...nope, tried 2 of them and both open fully as they should
(3) tuning issues...nope, timing is perfect and jetting is good, if anything it's slightly rich...not lean
(4) vacuum leak....nope, checked that and vacuum is low but rock steady
So as the conversation progresses Dwayne asks me what water pump and housing is on the engine....same one we dynoed the engine with ?
Nope....I upgrade to a fancy aluminum 440Source housing and pump. Dwayne proceeds to groan and suggests that i inspect the housing very closely. Why...the housing looks great and it's new and what the heck could be the problem ? Apparently he had one of those housings in the shop for a customer's FAST 511 build and didn't like what he saw. Externally the housing looks fine but the engine supply ports (lower openings) are very restrictive. You're kidding right....how can this be ? Nope...they are poorly designed and you'll see it yourself once you pull the pump housing and stick your fingers down the hole. scope
So, over the w/e i pulled the rad and all the front acessories off the engine to have a peek...sure enough the lower (supply) ports were very small. I compared this to the stock housing and it was like night and day ! On the stock housing i could easily get 2 or more fingers all the way into the hole but on the Source housing i could only get one finger in maybe an inch and it was jammed....WTH !!! icon_smile_angry
Looking at the two housings and comparing them it was apparant that the factory housing is a much better design ; the water passage makes a gentle radiused curve into the block and has lots of volume. The Source housing has a sharp 90* bend and the water passage is pinched off to maybe 20-30% of the inlet opening. Geez...what a PISS POOR design this POS is. That can't be good for coolant circulation and explains why the coolant was boiling inside the block....it was staying in there too long and forming steam pockets. yesnod
So, i re-installed the factory housing with my favorite Milodon water pump and fired it up. The engine ran for 20 minutes and hit 180* sitting there idleing in 108*F ambiant air temps....today was the hottest day of the summer by far....a real scorcher. I immediately noticed that the high radiant heat off the top end of the engine was gone...despite this being the hottest day i had ran the engine so far this year....the last time i ran it the air temp was 80*F. Looking at the coolant flow across the top of the rad i noticed immediately that there was a huge difference in flow....the coolant was circualting like it should be instead of just casually coasting by...which it had been with the 440 Source pump & housing. Encouraged by this i decided to take the car out for a drive to see how it would run....if it could run ok in 108* temps and not overheat...what more could you ask....that's about as bad as it can get ! So off i go for a cruise and it's running great....at speed the temp drops to 175* and holds that temp no problem. I try it in some slow moving traffic and the temp creeps up to 195*....not bad ! As soon as the car begins moving again.....the guage drops back to 175-180 and holds....Right On !!!!! 2thumbs
So, based on these results and close inspection of the 440 Source waterpump housing it's safe to assume that there is a major design flaw. If anybody is running this piece and has noticed increased temps and overheating you now know where to look. I have to give Kudo's to Dwayne for pointing me in the right direction. I hadn't considered that there was a problem with the design of this part because it visually looks good and i just assumed that the internal dimensions would be identical if not superior to the stock housing.....this is absolutely not the case. Tongue
Hopefully this helps those members who may be experiencing overheat issues and if you are running one of these Chinese knockoffs my advice is to replace it asap....or at least compare it to the stock housing to see what you've got.
Sorry for the long winded post but i wanted to give an accurate description of the troubleshooting process and how the problem was isolated and ultimately resolved.
Ron"
Also (dis is me talkin), I know many people here like 440 Source but man, they sell way too much stuff from China for my liking. And you would think after this long they would address that problem. At least get their Shineeeese producer to fix it.
