Why does my van run hot on the highway?

[turbovanman²]

Exact same setup as my 8 valve except TIII engine. Same 180 stat, I tried a brand new aluminium stock rad, old brass one looked fine. Around town, no problem, get on the highway, the guage goes between 1/4 and half. Cold days, 1/4, warmer days, flucutates, especially in boost which I know is causing more heat. UD pulley no difference. Is my rad the issue or waterpump?

Never ran hot with the 8 valve, guage stayed at the 1/4 mark, under boost etc.

[BadAssPerformance]

How lean is it?

[black86glhs]

Exact same setup as my 8 valve except TIII engine. Same 180 stat, I tried a brand new aluminium stock rad, old brass one looked fine. Around town, no problem, get on the highway, the guage goes between 1/4 and half. Cold days, 1/4, warmer days, flucutates, especially in boost which I know is causing more heat. UD pulley no difference. Is my rad the issue or waterpump?

Never ran hot with the 8 valve, guage stayed at the 1/4 mark, under boost etc.

You do realize that "between 1/4 and half" is not overheating. Just warmer than you like it to be. JT asked the #1 question. Are you seeing high EGT's?
Edit: Which tables did you mess with in your program? We know you were trying to lean them out. Maybe you have it too lean during cruise?

[BIG PSI]

Hook up a mechanical gauge and see what it reads.
Don't rely on an electrical one.

Chuck

[contraption22]

Hook up a mechanical gauge and see what it reads.
Don't rely on an electrical one.

Chuck

Or at the very least hook up a scanner and read what the CTS says.

[1FastCSX289]

.Why does my van run hot on the highway?

Because youre driving at 140 mph.

[turbovanman²]

I know NOT to trust the gauge but its accurate enough I know what the van is doing. The heater core gets hotter too.

Yes, I know its not overheating but I want to fix why its running hotter.

Should edit it has done this since the TIII swap, with any cal.

Egt's are 1500.

Because youre driving at 140 mph.

Hahha, good one,

[A.J.]

You shouldn't be running hot in the winter, and I wouldn't trust the factory gauge. I'd install a mechanical gauge and an oil cooler. Mine runs hot on the highway in the summer (ambient 110+). I have a stock radiator with a trans cooler and my intercooler in front of it.









Any opportunity to post pics of my van I'll take it.

A.J.

[GLHNSLHT2]

not as much airflow getting through the rad with a big T3 intake behind it? Got all the plastic shields forcing air through the rad?

[turbovanman²]

not as much airflow getting through the rad with a big T3 intake behind it? Got all the plastic shields forcing air through the rad?

The intake is really more in front of the intercooler. There are no plastic shields.

It must be the TIII head, or the way it flows coolant, its really weird. Maybe the engine runs hotter and that's just the way it is.

A.J, right now its around 5 deg c, so it likes to move around, when it gets to around 0 or colder, it sits around a 1/4 all the time, its really weird.

Figure I would try to get this figured out before summer hits.

[BadAssPerformance]

Egt's are 1500.

1500 at cruise? sounds a little hot?

[turbovanman²]

1500 at cruise? sounds a little hot?

Thats nothing, before I tweaked my cal, 1550-1600, my old G head 8 valve was 1600 and higher.

[BadAssPerformance]

Right, that was with a corkish head tho, so a more efficient head should be lower, right? What A/F do you cruise at?

[turbovanman²]

Right, that was with a corkish head tho, so a more efficient head should be lower, right? What A/F do you cruise at?

The G-head was ported, way higher EGT's than the ported Swirl, scary higher.

Right now, its around 14:1,

EGT's are about timing, I gave it more timing and it lowered them. I will be adjusting more as I play.

[Directconnection]

What Jay (glhnslht2) is getting at when he said "shields" is more or less of the air deflectors being used. You need shields of sorts to divert the air to go through the radiator instead of around it. The air will want to take the easiest path of resistance (pressure differential) and if it's easier for the air to go around your coolers, it surely will!

[BadAssPerformance]

More timing lowered EGTs? did it also lower A/F? I've had higher EGTs at cruise due to excessive fuel after burning in the exhaust.

14:1 off throttle and w/o boost is fine for cruising.

Re-reading your posts actually 1/2 gauge is ok if it is accurate.

Higher on the highway than in town? I've had bad HG do this. also, I remember someone had a cooling fan wired in backwards so around town it was ok but at highway speeds it was fighting the incoming air and stagnant thru the radiator! Doh!

[turbovanman²]

What Jay (glhnslht2) is getting at when he said "shields" is more or less of the air deflectors being used. You need shields of sorts to divert the air to go through the radiator instead of around it. The air will want to take the easiest path of resistance (pressure differential) and if it's easier for the air to go around your coolers, it surely will!

I know what he said, van's don't have any. The rad sits between a pillar and headlight stuff so air is already directed into it.

That doesn't change why the TIII runs hotter,

To me, its either a water pump issue, maybe it can't keep up or its to inefficient, the rad simply can't shed off the heat effectively or its just the TIII runs hotter and live with it.

[turbovanman²]

More timing lowered EGTs? did it also lower A/F? I've had higher EGTs at cruise due to excessive fuel after burning in the exhaust.

14:1 off throttle and w/o boost is fine for cruising.

Re-reading your posts actually 1/2 gauge is ok if it is accurate.

Higher on the highway than in town? I've had bad HG do this. also, I remember someone had a cooling fan wired in backwards so around town it was ok but at highway speeds it was fighting the incoming air and stagnant thru the radiator! Doh!

Yep, more timing will lower it, Brian even agreed. AF is the same, even lean or rich, still runs hot.

1/2 is ok but I don't like it, 1/2 is around 200-205 on the scanner, didn't do it with the 8 valve. Maybe Jay is right, the bigger motor is blocking more air BUT it sits to the right, not behind the rad????????

It has done it with every TIII reincarnation, so its not a head gasket,

Ran fan untouched and runs the correct way. It runs ok around town, goes to hot, fan turns on, cools down, like its supposed to.

[BadAssPerformance]

Ducting may help then... I had to duct the radiator with the 2.4L but tahst cuz th efan moved to a pusher instead of a puller and the intake and FMIC block a bit of flow

[turbovanman²]

Ducting may help then... I had to duct the radiator with the 2.4L but tahst cuz th efan moved to a pusher instead of a puller and the intake and FMIC block a bit of flow

Not much really to do, the factory did a good job for us vans,

I might have access to a high quality Civic aluminium rad for cheap, so I might try that.

I was bidding on an electric inline waterpump but it went for too much, lol.