I've seen a few posts on here but my setup seems to match most of what people have running in their cars without issue. I have a 455, stock crank and rods, 10.5:1, iron Stage 1 heads, TA Stage 1 intake, Holley 850, stock replacement water pump, Champion 3 row aluminum radiator, 16" electric fan, Evans coolant, 185* thermostat. Im running about 210*-215* on the highway when its sunny and 85. Any tips?
Buick always run hot. That's what my Dad always told me. I have a similar issue and just ordered the TA HP water pump to address the problem. I would however like to hear options for cars that are never started below 50*.
The Champion 3 row radiator is suspect. If the tubes are small, it is no better than, and may be inferior to a 3 row Brass/Copper radiator. And yes, what is your total timing, including vacuum advance at your cruise RPM.
Not familiar with electric fans but, if you have a factory shroud you could be running an 18 inch or even a 20 inch fan (if your shroud is a '71 or '72). The above comments about the Champion 3 row and checking your timing and vacuum advance are also very important. You need lots of timing for cool running as well as good performance.
I'll have to check on the timing. I was thinking it was in the low 30's BTDC at about 2,000RPM. I don't have the vacuum advance plugged in because I've had more trouble than luck using them in the past. Although, this is my first Buick build. What should the timing be at idle with the vacuum plugged in? At full advance? I've been toying around with upgrading to a Spal cooling fan but that's not going to get me much when cruising. Here's a link to the same radiator on eBay. http://www.ebay.com/itm/1968-1969-1...-Row-Champion-Aluminum-Radiator-/161467440616
Of course they tell you everything EXCEPT tube size. If tube size is 1" or more, you don't need more than 1 or 2 rows max. You want cruise timing to be in the low 40's. If you modify a stock vacuum advance to supply 10* of advance at light load cruising, you are there. Check your timing, sounds like you aren't sure.
It looks like the radiator has 3 rows of 5/8" tubes but they claim cooling capacity of 600-800hp. And, unfortunately....I'm nowhere near that. I'll check the timing to get an accurate number.
Well many times it goes like this. Some one rebuilds there motor with better flowing heads and Manifold , or up grades a motor with such and then they plop back on the same Carb they had been running before the better flowing parts and now they have a hot running motor at cruse rpm's due to a lean Carb!
Yeah, that is what I thought. The biggest reason for using aluminum for radiators is it's stiffness compared to brass/copper. Tube sizes can be as big as 1 1/2", and that what increase cooling capacity. Brass/copper actually transfers heat better than aluminum, so this radiator is likely inferior to an equivalent brass/copper radiator with 5/8" tubes. I have been warning V8 members about this for a long time.
I agree and have seen the same but this is an entirely new build and I had the carburetor setup by a very well respected local shop with the engine, trans, rear end gear, and vehicle weight info. I trust that the carb is functioning properly.
If the car heats up on the highway and cools down somewhat when you slow down in regular traffic, that indicates that the radiator doesn't have enough capacity.
I do not think Buicks run any hotter than the 330 in my Cutlass or the LT1 in my old Camaro. proper cooling is more than just radiator size and airflow. ignition timing plays a significant role at idle and at road speed idle speed plays a significant role at idle proper fitted shroud (to radiator and fan) plays a large role at idle rear end ratio plays a significant role at speed all of these factors play off each other my set up does not overheat at idle or run hot on the freeway even with the AC running in 110* Sacramento heat. 42* advanced timing at freeway speeds. 30-32* from the distributor and another 10-12 coming from modded vacuum advance stock size AC clutch fan 2747 Hayden fan clutch (a "severe duty" one is an option if you are that worried) fan shroud from TA performance trimmed so the fan is 1/2 in 1/2 out stock style water pump and pulleys champion two row 1" core all aluminum radiator 180* "high flow" thermostat idle speed set to 550-600 in D with AC running and engine **FULLY** warmed up The highest temps I have seen is 206* at idle with the ac running and 111* outside. The temps dropped to closer to 190 once on the freeway. at car shows I'm one of the few people that enters and leaves with the widows rolled up and the ac going while waiting in line. Stock these engines were designed with 195* thermostats and locked out extra advance until reaching 220-225* then it would add timing from the vacuum advance which bumped the idle speed to cool things down. **the stock thermostat is 195* and because I am using a lower temp thermostat with a lot of airflow (i.e..driving down the road) the engine drops to 180 which makes the fan clutch only partially lock up great for performance and economy but will cause the idle to be 50-100 rpm higher than it 'should' be until it builds heat then the clutch locks up again which puts a slight load on things thus dropping the idle speed. as you can see I am pretty autistic when it comes to this aspect of my car lol
This is almost the exact same cooling arrangement and ignition curve I have for my 464 CI performance build. As has been said, the right radiator, fan, clutch and ignition curve will go a long way towards keeping things cool.
I'm starting to be a huge believer in the timing aspect. I don't think I am getting the vacuum advance from the weak a$$ vacuum from the base of the carb, I think something is not right there.
That will for sure affect cooling at cruise speeds. All of the other posts that have specified info other than "my dad says" contain correct info also. (no hating, just a humorous way of commenting)
It doesn't matter how reputable your carb shop is. It will not functioning properly if the timing curve is goofed up. It is also questionable if it is able to function correctly if major changes to the engine aren't accounted for.
Poke around with a vacuum gauge to find the manifold vacuum source. On my Quadrajet, there are three ports on the front of the carb. The lowest one, near the base of the carb, doesn't seem to do much of anything. Strange and mysterious. The one off to the right is the ported vacuum. The one off to the left is manifold vacuum. I used some vacuum Ts to build a contraption such that I can run my vacuum gauge and vacuum advance off the same port when I am doing tuning- this has been a massive help. Once you find out how much vacuum your car is making at idle (in drive), you want to pick a vacuum advance that is "all in" at approximately 2 inches of mercury lower than your idle vacuum. Having the VAC "pegged" at idle will help make your idle speed more stable, and make it easier to set your timing for optimum cooling, mileage, and performance. You want to be at 25-30* BTDC at idle, for best cooling performance. A car tuned "stock" is set at 4* BTDC, with no additional timing from the VAC, due to the ported vacuum situation. This was done to reduce tailpipe emissions, at the cost of lousy throttle response and drastically increased engine temperature. Most VACs provide 16* of timing, so an initial timing of 10-12* will get you in the ballpark for idle cooling. Read Larry's timing thread in the FAQ, for more timing info. He likes to limit his VAC to 10*, rather than 16*. This lets you run more initial timing for better WOT performance, but still avoid getting too much advance at highway cruising speeds. I have tried it both ways, and am still trying to decide which I prefer. Google "lars grimsrud vacuum advance" and read Lars' treatise on Vacuum Advance Controllers to learn more about how these things work, and to view his spec listing. There is a ton of tuning available in these neat little $14 packages.
Bear with me...Got back from 20 minutes each way mixed driving and the temp is 250.. Now at 1500 rpm Without manifold vacumm to dist 6* With mv 38* Now I am getting closer..... should I wait on bring the radiator in?
