Engine temp rises when I get to cruise speed

I too believe that 205 degrees is too hot - given the short amount of driving you did. Also, you really weren't under any heavy load (that you said) and it wasn't 100 degrees out.

If it was mine, I'd give Brassworks another try and see if Lee can meet you 1/2 way - to put in a bigger core and lower the temp another 10 degrees or so. Even though you have a pressurized radiator, the higher the heat of the engine, the more chances for detonation (especially with a blower) - and detonation is bad JuJu for an engine.

While this is a big an expensive pain in the butt - it is the right direction to head. I'd also much rather run a quality copper core radiator than an aluminum one -- for aesthetics and longevity.

I agree 100%. I don't want detonation! Let's see if Lee wants to work with me. It might be best to have that work done locally to save on shipping etc. Maybe he's willing to kick in. He never kicked in for the repair that was needed with less than 10 miles in the radiator so I seriously doubt it.
 
I installed a larger overflow tank today to rule out a possible problem of losing coolant out of the smaller tank I had. It' a crude plastic bottle, but it'll serve the purpose.
I know, I know it's not going to do anything, but I have to try. If anything, maybe we'll get some good info out of this post.
 
Please, take the time and effort to reinstall the aluminum radiator without any other changes and see if it lowers the temp. If it does then you can let Lee know that his radiator is the issue.
 
I'm curious. Does the blower really come in to play under your present normal driving conditions, i. e. cruise?
 
I'm curious. Does the blower really come in to play under your present normal driving conditions, i. e. cruise?

I really don't think so. I only get the boost up when I get onto the high way and that's short lived. Most of the time is just high way or backroad cruising between 35-65 mph depending on traffic. I know it does rob horsepower just to spin the blower, how much I don't know. On the top fuel cars that are producing 11,000 horsepower, it takes close to 1000 hp to drive the blower!
I know my timing is slightly retarded at cruise with the blower because I don't have a boost timing module to pull it out.
 
Please, take the time and effort to reinstall the aluminum radiator without any other changes and see if it lowers the temp. If it does then you can let Lee know that his radiator is the issue.

That's going to be my next step. I want to try the overflow tank for the heck of it, then I was planning on taking the radiator out and putting the China Special back in.
 
I really don't think so. I only get the boost up when I get onto the high way and that's short lived. Most of the time is just high way or backroad cruising between 35-65 mph depending on traffic. I know it does rob horsepower just to spin the blower, how much I don't know. On the top fuel cars that are producing 11,000 horsepower, it takes close to 1000 hp to drive the blower!
I know my timing is slightly retarded at cruise with the blower because I don't have a boost timing module to pull it out.

Why not bump the timing up where it should be for cruising and see if the temp comes down. Just don't romp on it.
 
My bet is not much if any. 21 is pretty good and likely very little will be realized by going higher. I've not seen any difference on mine.


My 2 cents on the blower...At your cruising speed of 55-60 mph that blower is making very little boost and thus takes very little power to turn, which means it adds very little heat load. Wide open throttle and 5000 rpm would be a whole different story.



Just my thoughts from 50 years of being in business as a mechanic and engine builder. Learned a lot the hard way for sure! :D


Terry (betting the old alum rad will fix it ;))
 
My bet is not much if any. 21 is pretty good and likely very little will be realized by going higher. I've not seen any difference on mine.


My 2 cents on the blower...At your cruising speed of 55-60 mph that blower is making very little boost and thus takes very little power to turn, which means it adds very little heat load. Wide open throttle and 5000 rpm would be a whole different story.



Just my thoughts from 50 years of being in business as a mechanic and engine builder. Learned a lot the hard way for sure! :D


Terry (betting the old alum rad will fix it ;))

So at 60 mph in 5th gear, I’m at 2500 rpm and 10 inches of vacuum. No boost at all. I really don’t see boost until I mash the throttle and the rpm’s come up.
 
Just curious, but I wonder if the blower could be adding a little air to the engine to reduce your vacuum at cruise. My 276" naturally aspirated runs 17" at cruise. It has a 278 degree cam (L100).
 
Could leaking head studs be a sign of a head gasket problem? I tried many times to remove, clean and replace each one using all different types of sealants and a couple still leak! Just wondering if I have a problem that could be causing the high temps. I did the liquid test to look for hydrocarbons and it came up clean. I don’t know if that test is 100%
 
Head studs will commonly leak if they were NOT sealed correctly when installed (has nothing to do with the blower).

I use a liquid stud-sealer from ARP. Even with that, sometimes I'll see a few that will weep a bit before they usually seal themselves. It isn't a bad idea to run a batch of Morose 'Ceramic Seal' through the engine after it is first built - helps seal up some of these pesky studs.

Typically, if you have a blown head-gasket, it will get worse (especially with boost) and you'll start puking combustion gasses into the radiator or water out the exhaust ports . . . or some combination of both. If it gets bad, you'll see your plugs getting "washed down" and may even blow water out a spark plug hole if you pull them. You definitely don't want a head-gasket problem - as it can also hydraulic the motor if a bunch of water gets into a cylinder.

The usual test is to get the engine hot, then come back and pull the radiator cap and see if you are getting bubbles coming up through the coolant. With that said - be careful opening up a hot radiator (especially if under pressure).

Good luck!
 
Head studs will commonly leak if they were NOT sealed correctly when installed (has nothing to do with the blower).

I use a liquid stud-sealer from ARP. Even with that, sometimes I'll see a few that will weep a bit before they usually seal themselves. It isn't a bad idea to run a batch of Morose 'Ceramic Seal' through the engine after it is first built - helps seal up some of these pesky studs.

I guess I missed that opportunity!

Typically, if you have a blown head-gasket, it will get worse (especially with boost) and you'll start puking combustion gasses into the radiator or water out the exhaust ports . . . or some combination of both. If it gets bad, you'll see your plugs getting "washed down" and may even blow water out a spark plug hole if you pull them. You definitely don't want a head-gasket problem - as it can also hydraulic the motor if a bunch of water gets into a cylinder.

In that case I seem to be ok.

The usual test is to get the engine hot, then come back and pull the radiator cap and see if you are getting bubbles coming up through the coolant. With that said - be careful opening up a hot radiator (especially if under pressure).

I did perform that test when I had the filler funnel attached to the filler neck and no bubbles appeared!

Good luck!

As usual, thank you for responding, it really helps and I appreciate it very much.
Joe
 
I ran the car today just long enough to get it to about 200 degrees. The larger overflow tank I temporarily installed did fill up and I wouldn't say violently, but it seemed to be pretty forceful. I think maybe there was some air in the system from the last time it cooled down and the tank went empty.
I would image, if that's the case, that air went through the system and that was purging that I saw.
I won't know if this will help anything until I get a chance to take it for a full ride. Looks like we have some rain coming this weekend in Jersey, so we'll se how it goes. I'll post results as soon as I can
Thanks Joe
 
I run it in 2 flatheads & 350 in the desert of AZ & haven't been towed yet !!!

B-O-B, I received the RMI-25 today, but I won't put it in until I run the car again and check the overflow tank situation. I'll keep you posted.
Thanks,
Joe
 
Another bothersome question; but curiosity is getting the better of me, wondering what are the differences between the ebay aluminum radiator and the brass one. Core size, etc.
 
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