Mild 340 build runs hot

[John Trickler]

I have a mild 340 build. Stock bottom end, 30 over, Hughes whiplash cam, Eddie heads and a Summit knock-off Air-Gap intake, FAST EFI. It runs hot, 215-225 degrees. Last fall I tried multiple thermostats. Currently have a high flow 180 degree in it. Running CVF Wraptor serpentine system. Way big BeCool radiator. Radiator and 2 Spal 1522 fans, the radiator is doing the job, heat temp gun shows that. My question, I don't remember which head gasket I used, would have been a Fel-Pro though, is there a difference in the head gaskets orientation? Front to back? I am about ready to start tearing apart the engine to look for a problem, intake first.












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[toolmanmike]

Usually the Serp set up is the cause.

 

[Plymouth 65]

What water pump are you running? 65

 

[John Trickler]

What water pump are you running? 65

The water pump that came with the CVF kit.

 

[mopowers]

Usually the Serp set up is the cause.

How so?

 

[toolmanmike]

How so?

Pulley diameters different than the originals.

 

[TXOval]

I run the CVF serpentine system, but alternator only kit.

340 stroked to 416 in 66 Barracuda and it will max out at 195 on a hot Houston day. Holley Sniper and dual electric fans on Champion radiator.

I’ll have to look up my fan again…I switched from a different brand and it helped a lot

Be Cool 75007 Be Cool Qualifier Fans | Summit Racing

What I’m running now…

 

[Oldmanmopar]

Way big becool radiator in mine, couldn't get it under 240 degrees. I tried everything. Becool radiator was no good . tubes were swell from being pressurized and would not flow sufficient air.

 

[John Trickler]

Way big becool radiator in mine, couldn't get it under 240 degrees. I tried everything. Becool radiator was no good . tubes were swell from being pressurized and would not flow sufficient air.

View attachment 1716428641I have a nice temp drop through the radiator, but I will check it out. I need to find out what is going on.

 

[mopowers]

Pulley diameters different than the originals.

So you think his serpentine setup is spinning his pump too fast?

 

[Inertia]

What's the temps of the upper and lower rad fittings, not the hoses, the actual temps.

 

[crackedback]

So you think his serpentine setup is spinning his pump too fast?

usually too slow. They tend to run reduction of speed from stock pieces.

 

[TXOval]

Have you messed with timing/AFR with your efi setup?

 

[John Trickler]

What's the temps of the upper and lower rad fittings, not the hoses, the actual temps.

My memory sucks, I don't remember the exact numbers. I know it was significantly different top to bottom. After I check out some things tomorrow I will run it and record the numbers.

 

[mopowers]

usually too slow. They tend to run reduction of speed from stock pieces.

If I remember correctly, I think those CVF systems overdrive the w/p.

 

[John Trickler]

Have you messed with timing/AFR with your efi setup?

Timing is not controlled by the EFI. I richened up the AFR a little. I had a video with the numbers, but I just fat fingered the phone and deleted it, not the one I wanted to.

 

[Inertia]

My memory sucks, I don't remember the exact numbers. I know it was significantly different top to bottom. After I check out some things tomorrow I will run it and record the numbers.

It could significantly shortcut things, we usually go 130 posts on these threads, each year, - after year. tia

 

[John Trickler]

Here is a picture of the setup before hoses were attached.

 

[1WildRT]

Put more timing in it & see what happens...I have a similar 340, spent weeks chasing an overheat condition, in the end I started adding timing, every time I added 5 degrees of timing the temp dropped 10-15 degrees...

 

[John Trickler]

Put more timing in it & see what happens...I have a similar 340, spent weeks chasing an overheat condition, in the end I started adding timing, every time I added 5 degrees of timing the temp dropped 10-15 degrees...

Do you remember your initial timing?

 

[crackedback]

try about 18, as long as the starter doesn't kick back, you are safe there.

Then limit inside distributor or table so total isn't out of bounds.

JMO, as long as the AF wasn't lean, don't add fuel as that may make the issue worse. Add timing and set the fuel back where it was would be my starting point.

 

[1WildRT]

Do you remember your initial timing?

Yeah, and it doesn't make any sense... Advance is locked out, base timing is 35 degrees... It starts fine, never pings & it runs strong... For a while after I set it up this way I kept trying to fix it cause there's no way it should be run that way... Finally I was talking with a friend who's always been a tuning guru type, he said the engine will tell you what it wants,... Give it what it wants & quit worrying about it...

 

[Dana67Dart]

It runs hot, 215-225 degrees

We always seem start in the middle... lets start at the beginning

under what conditions does it run hot? idling, city , highway?

 

[harrisonm]

I am not the biggest fan of electric fans for cooling in our classic cars.
1. When I bought a Griffin Perfect Fit aluminum radiator about 15 years ago, I bought it with their fancy shroud and fan setup. I had trouble with the engine getting too hot and tried just about everything. I finally trashed the fan setup for a stock, repro fan shroud and metal fan blade. It cooled much better then.
2. I don't like what I see in the picture in post #18. IMHO, without a shroud, you are only sucking air through the radiator in the areas right in front of each fan. That setup may work OK going down the highway where there is plenty of air going through the radiator, but at idle and stop and go traffic, you will not be getting sufficient air flow.

 

[Bewy]

You will want closer to 25-30* at idle with the WhipTrash cam for best idle quality & tip in response. However, it might have a small affect on temps but I think the main problem is elsewhere:
- the w/pump needs to be overdriven 10-20%
- I would lose the elec fans which act as a baffle & are failing to use the full area of the rad core.
- which water pump
- www.stewartcompoonents.com