Who has heard the thin-walled cylinder 455 engine is prone to overheating.

WoW, that's a Hot Tahoe.
I have been told all kinds of temperature numbers that are supposed to be too hot for my 70 Buick GS 455.
In fact, the shop that is working on it are going bananas over it because they don't know Buicks and keep telling me it's to Hot.

I just bought a Griffin aluminum radiator two days ago. I'am not sorry I spent the money on it, I just want to feel safe driving it in the summer.

It is only getting hotter every year.
The main issue I have with classic car shops, there are so few Buicks, most shops have very little experience working on them.
Thanks Mark for assuring me that the temps my Buick is operating at is really normal. VET

 

Yes, I just bought an Griffin aluminum radiator that Larry GS70 recommended.

I also read an interesting article written by a Buick guy, all about fan clutch s and fan blades.

My Buick came with an 18 inch diameter 7 blade that has a 2 1/8 inch pitch. I had it measured.
Since it's pitch is less than 2 1/2 inch's, I should be running a SD fan clutch NOT a HD model.
So, I had the HD clutch removed and a bought a SD clutch from Todd Miller. Wow, no more roaring noise. This thing was so loud, I couldn't even enjoy my new radio and speakers.
Now, I've got it back to where it belongs.
I have to tell you the Service Manager got into it because they ran out of ideas how to solve this heating problem and I had to do all the trouble shooting.
Hum, I should have been getting paid to do that. Lol.

We are on the road to recovery, that's all I care about now.
Thanks Mark. VET

 

LOLOL!
Yes most all new cars run well over 200 degrees.
My wife’s Tahoe runs at 210 also
My ‘01 Safari AWD van with the 4.3 V6 ran at 205/210 all the time, NEVER ran hotter than that, even on a 102 degree day with the ac on.
Couple things to chew on,
A lot of shops that work on our older cars are fixated on the urban tale that 200 or 210 is HOT, yes it’s hot, is it optimal? No.
I’m going to surmise the “run it at 160/180” came about around the same time the old copper/brass radiators were beginning to get plugged, “this thing is running too hot”
The default came to be “put a cooler thermostat in it”
The usual outcome was it still ran over the thermostats rating, and the cause of that was the radiator’s inability to Absorb and reject the heat to the atmosphere via the engine fan at low speeds and natural airflow at speeds above say 30 mph.
This was all due to the insulating properties of the goop that formed from too old a coolant mix, solder blooms and such.
The OEMS went to aluminum for radiators because of their lighter weight and better heat absorption, therefore they could run the engines over 200 degrees without worry of a boil over, something a copper/brass radiator has issues with, even brand new.
If you look under the hood of any new car, with all the plastic engine covers, on a hot day, after the car has been on the highway with the ac on, or worse yet, stop and go city with the ac on, the temps are stable at 205, 210 or whatever they run them at. You’d think the engine would melt when you open the hood and that heat comes wafting upwards, nope, the engine is just fine
Cooling systems have advanced since the 70’s and 80’s

 

I love your history lesion lol.

My buddy's 1964 Vette I believe came with an aluminum radiator. The GM boys already knew it was time to get rid of the coop/brass models.
When I go to the shop, I notice they go to the auto manual (Buick in my case) and look up stats. In my 1970 Buick owner's manual, I see that Buick calls out for a 190* thermostat on ALL V8's. Everybody tells me to put in a 160* thermostat that is a high flow model, so I did.

After seeing what you just said, Buick already knew that their Buicks would run all day long at 210* or higher. That now makes since.

Here's a question for you. When I bought my car, the engine had been rebuilt to Stage 1 engine specs.
(1) Bored .030 Over. Only because it had 78,000 miles on it and I suspect it had a ridge at the top of the cylinder wall, that needed to come out to get the pistons in and out.
(2) An aftermarket Hydraulic Comp cam that has a little more power that the Stage 1 cam.
(3) Heads were machined to take the large Stage 1 valves. Amazing, the cast iron heads for the small & large valve heads have the same casting numbers. Never seen that before.
(4) The previous owner installed Kenne Bell pistons that have valve reliefs. Saw this with a borescope down the spark plug hole. Now, I have no idea what compression I have? But I know is hasn't been decked. So, I speculate that the pistons are in the hole .040 and has .040 Felt-Pro head gaskets. That's what these pistons call for. FYI: LarryGS70 ID'ed these pistons and sent me a copy of the Kenne Bell catalog.
Using a CR calculator, I should be at 9.4 CR, that's only a guess so far. I'm not pulling the heads to do exact measurements at this point.
(5) Plus, I had an MSD ignition installed because of the detonation issues I was having.

That all said, I noticed the mechanic installed AC R45TS plugs. That's for a 350ci engine. All, 455 engines are to have AC R44TS plugs.
Also, he has my initial timing at 6* BTDC and the Stage 1 is 10* BTDC.

I sent an email to the shop owner asking him why his mechanical did this?

I suspect that the mechanic, using the car's factory numbers know it started life as a stock Base 455 with 350 hp.
I have told him it's been modified to Stage 1 specs. Guess he forgot with all the cars he works on (70 classic at their shop now, mine is the ONLY Buick).

I am overreacting, or should I have the mechanic make the changes I called out?

He already tuned the Buick; total advance is 32* at 3200 rpms. I was going to have total advance come in at 2500, but LarryGS70 told me not to because of the engine's sensitive to detonation issues.

Long winded to get to my questions. Sorry about that, but the more you know the better I believe it is.

Let me know what you think, thank you. VET

 

OK, guess it takes me a while to absorb all the information I'm reading from various forum members. W as telling Mark, I've been told to install a 160* thermostat and that's what I did. However, I read in my 1970 Buick owner's manual that Buick installs 190* thermostats in all V8's.

Question: Should I now remove the 160* and install a factory 190* thermostat?
I'm so confused from time to time. I know everyone is trying to help me, but I get a barrage of, "DO This, DO That".
Most of all these suggestions seem logical to me. I just can't separate the good from the bad.
I don't have the Buick knowledge and experience you both have (Larry & Schurkey). I understand Chevy's a lot better and this is my "FIRST" times having both detonation and overheating problems.

Larry, according to the owner of the shop working on my car, your recommendation to buy a Griffin radiator excellent.
He has installed a lot of these Griffin radiators, and they are still made in the good O' USA. I will await your response to my thermostat question.
Thank you very much, you too Schurkey. VET (Navy)

 

I like to keep the cylinder walls as thick as possible,for better ring seal and to help with cooling. As far actual cooling goes,I haven’t had any cooling issues with any of my cars. They all run in the 180-190 range,no matter what.

 

I like a cool running engine, so I will leave in the 160* thermostat.
You are dead-on. I had all kinds of engine issues inhered for the previous owner. I found all kinds of mechanic notes in the car after buying it (unseen).
Mechanic notes: Detonations at all RPMS.
Runs HOT, needs a new radiator (HD 4 Core Model), just installed a 160* thermostat, still running hot.
Distributor: Points type needs rebuilding. Just finished, total advance is now 35*. Detuned advance by 7*.
I almost fell out of my chair; this car had a total advance of 42*. REALLY. How did this car even run???

These are just some of the mechanical issues notes. Surprised the Consignment Dealership didn't trash these notes.

The engine was in sad shape when I got it. Crank damper was falling apart, replaced that with a TA Performance model.
Crank damper key was damaged too. Someone damaged it with vice grips, can't believe that, a first for me.
Timing chain was stretched way out of shape. Replaced that too.
Took off the valve covers only to find that the nylon rocker keepers were not even correct for this engine. Had to buy a complete new set from TA Performance.
Once valve covers were off, we could see that someone in a rush over sprayed the heads with paint, covering rocker arms and push rods.
Real trash job. Don't ask me if I was pissed!!!!
Replaced the water pump TA's high-performance pump.
Replaced the entire A/C system.
Even the QJet was damaged beyond repair. Replaced that.
I could go on, but you get my drift. VET

 

Hi Brian, Good question. I don't know the model number, but it brand new.
This is what I know, it's a digital model. I had an adjustable vacuum advance canister installed.
Right now, I'm told the engine run good, but we are on the last leg of the overheating problem, ne Griffin aluminum radiator coming in any day now.

Strangely enough the first MSD ignition died. So now I have a second unit. For some reason the mechanic didn't install the MSD coil on the first MSD system but did on the second MSD system. I will have to ask him why all this occurred.

I was talking to the shop owner and asked him why the MSD ignition failed. He said this is unusual for MSD, but he has noticed a drop
in their QC.
He has also noticed a lot of returns of automotive parts back to the various vendors because of poor quality control work and just plain poor workmanship.
It's now so bad with carburetors, his shop is now rebuilding them. Even though it is more costly for the customer, the time he ships them back and they rebuild them, it's months later. He told them, just ship me another carb, no, we can't do that, we have to rebuild the one that's not working for you. So, in order not to increase his workload, he rebuilds them. Pretty sad situation in the classic car world. VET

 

Larry, I worked on Chevy's during the leaded gas with high compression days.
My last Chevy had 11 1/4 to 1 CR. Never had dedonation or over heating problems.

This age on unleaded gas and low compression engines takes a lot more understanding how to generate hp.
Of course, when you start with a screwed-engine build it's much more difficult to work with instead of building from scratch. Scratch engine building is all I know, trying to
fix or trying to figure out what the guy before me did to this engine is not my forte.
Also when I was building high performance engines, I used only GM Chevy internal parts.
Pistons and cams, large valve heads were factory.
Aftermarket only included intakes, headers, transmissions, ring & pinion setups and ingnition systems.
I never had an issue, with exception of finding the correct cfm carburator. Which I finally did. My old 56 Belair turned a 12.2 ET.
I don't believe I'll be even to get my Buick into the 13 ET bracket without a lot of engine work that I don't have the money for anymore after spending a ton just trying to get it back into driving shape.

Sorry to be a bit of a downer, guess i'am just a bit PO'ed.

Again, I really appreciate your help and Buick expertise.
You are a high credit to this forum. VET

 

Yes, I don't have a garage. I live in a townhouse. I store my Buick in a storage facility. Not allowed to work on it in this facility, insurance issue.
Even the electricity is on a one hour timer.
Many years ago, when I started a family and a career that required me to live overseas in different locations is not going to work on a classic car.

You see, when I left private industry, I took a job with the CIA as an uncover Technical Operations Officer. My job was to solve technical problems facing our Operational Missions, which are all overseas. If you like James Bond movies, the amazing Tech called Q, this is the type work I did for 32 years. I also was engaged in hunting down the 911 Terrorists that killed a lot of fine Americans who attacked the twin towers. Worked with Special Forces on hostage rescue missions. Served in Dessert Sheild.

Never had a normal 40 hour work week. This doesn't leave any time to work on cars.

Now that I will be 75 in a few months my classic car years are very limited. Now you know

 

Late model vehicles run over 200 because they were designed to. They will have a minimum of a 195 thermostat. A performance vehicle should not, especially if you put a 180 thermostat in it. If the cooling system has adequate cooling capacity, it should run right at the tstat rating or slightly above it, worst case

 

That's good news to know.
Like I've been telling everyone, I've built SB Chevy engines a long time ago and never really paid any attention to thermostats because I've never had a high water temperature problem, ever. My Chevy engines ranged from 11 1/4 to 12:1 CR.

The only problem I had was the 12:1 engine, had to retard the timing and add some avgas to get it to stop dedonation under WOT.
Of course, that was the leaded gas days.

This Buick is my first experience with high water temperatures. So, to get this cured, I will try anything and I have.
The Griffin aluminum Radiator should be here by the end of the week and installed next week.

My problems should be over and I won't be on the forum ask a lot of questions anymore.

 

Ask any questions you want, plus if you drive an old Buick, your problems are far from over LOLOL

 

Driving anything old, you can count on a wrenching project. lol

 

This may be anecdotal, but my 68 430 was running ~220 degrees with no A/C. Installed a nice 2 row AL radiator, replaced fan clutch, thermostat, etc., not much difference. My front timing cover had a cracked bolt hole which was seeping coolant, and I had a pristine cover that was like new, so I swapped it out and replaced the water pump with a standard duty T/A pump. Now the temp never gets above 185 (180 t-stat is same as before), The original water pump was not seeping out the weep hole, and bearing was fine after I pulled it. The original front cover had an indentation next to the pump blades, which looked to have been cast that way (?). So it appears that in my case, it was a bad timing cover causing excessive temperatures.