SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: SCRAPHANDLER on May 11, 2021, 06:56:52 PM

Title: BBC 454 temp
Post by: SCRAPHANDLER on May 11, 2021, 06:56:52 PM
What water temp should I be showing while running/idling? I attached a pic of my set up. I had one guy tell me 150 ish and another said between 160/180.


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Title: BBC 454 temp
Post by: SCRAPHANDLER on May 11, 2021, 06:58:39 PM
Here’s a photo of dash and temp gauge

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Title: Re: BBC 454 temp
Post by: sevans01 on May 12, 2021, 06:40:16 AM
both of you the answers are the same I've heard. 140-150ish idling to 170-180 ish while under way. search temps, its been covered several times.

btw nice looking rig you got! good luck 
Title: Re: BBC 454 temp
Post by: Grimpala on May 12, 2021, 11:56:11 AM
I try to keep mine under 180 at idle, it'll cool off under power.
Title: Re: BBC 454 temp
Post by: sevans01 on May 12, 2021, 12:50:19 PM
I try to keep mine under 180 at idle, it'll cool off under power.

yup you're right, got my numbers backwards, thanks for the correction!
Title: Re: BBC 454 temp
Post by: mash on it on May 13, 2021, 08:31:27 AM
Do you have a gate valve at the pump?
Set it for 140°f at cruise. Its a single pass system, it gains (passes) more heat than a car/closed cooling system.

Lower water temps gain horsepower. It's been proven on the dyno for years.

At 180°f, lake water is precipitating hard water minerals into the water jackets, a recipe for disaster.

I wouldn't run it over 160°f, ever.

Some simple math-
Lake water in @ 70°f, + 70°f heat gain from the engine, 140°f.
A good radiator only cools about 50 degrees. At 210°f output, the radiator will cool it ~50°f, or to 160°f, -ish.

Higher temps in cars are mainly for emission requirements.

If it had open headers, I'd run it at 110°f, at cruise.

Just my $0.02.

Dan'l
Title: Re: BBC 454 temp
Post by: 76Mantra455 on May 13, 2021, 03:00:02 PM
On my 455 the temp will get to about 130 thru a long 5mph zone after i take off it drops back to 100 and this is on a hot summer day outside temps 100 degrees out

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Title: BBC 454 temp
Post by: SCRAPHANDLER on May 16, 2021, 07:21:16 PM
both of you the answers are the same I've heard. 140-150ish idling to 170-180 ish while under way. search temps, its been covered several times.

btw nice looking rig you got! good luck

Awesome thank you here is a pic of the whole float.

And I just seen the comment below I was going to say it cools off under way.


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Title: Re: BBC 454 temp
Post by: SCRAPHANDLER on May 16, 2021, 07:24:12 PM
Do you have a gate valve at the pump?
Set it for 140°f at cruise. Its a single pass system, it gains (passes) more heat than a car/closed cooling system.

Lower water temps gain horsepower. It's been proven on the dyno for years.

At 180°f, lake water is precipitating hard water minerals into the water jackets, a recipe for disaster.

I wouldn't run it over 160°f, ever.

Some simple math-
Lake water in @ 70°f, + 70°f heat gain from the engine, 140°f.
A good radiator only cools about 50 degrees. At 210°f output, the radiator will cool it ~50°f, or to 160°f, -ish.

Higher temps in cars are mainly for emission requirements.

If it had open headers, I'd run it at 110°f, at cruise.

Just my $0.02.

Dan'l


Yes I have a ball valve on the feed line. I usually try and set it for around 150 while cruising.


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