Hi guys,
Got a question and you guys are going to know this.

After many months of waiting, I've finally arranged to get the Valiant towed over to my shop and finish up the motor swap I started last fall. All that remains is installing the floor shifter, manual valve body, and some exhaust bending and we are on the road again.

Anyway, my question concerns carb heat. What exactly does having a heated intake do for an engine? My slant has a draw-thru turbo setup whomped together from 70s Buick parts. The guts of the arrangement is a sort of box that sits on top of the intake manifold, allowing air to be drawn thru the AFB then to the turbo, and then back to this box and into the intake. The box has provisions for hot engine coolant to heat this whole box, right on top of the intake. Currently this coolant isn't plumbed, but it would be simple to hitch it up. Motor seems to run okay without it, but since the car isn't roadworthy I have no idea where I need to be in terms of carb, timing, boost, etc.

I know compressed air means heat, and that's why modern setups run intercoolers. But why is this thing heated? Would more heat mean less air, hence less spark and less power? What's the theory behind this?

Kip-on-Truckin'

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1965 Valiant wagon Turbo slant (work in progress)
2000 Chevy 155" cargo van - The Abductor
1970 Newport convertible
1996 Buick Roadmaster Wagon
1966 CruiseAire motor home
1990 Toyota 1 ton box truck TURBO slant (scraped)

<a href='http://pictures.aol.com/galleries/kipswork/9340GuB1pinzS4zsstAwWtthHVSzlxroylhJv4xQp5Fd3Ig='><img style='border-width:0px' src='http://links.pictures.aol.com/pic/9340GuB1pinzS4zsstAwWtthHVSzlxroylhJv4xQp5Fd3Ig=_m.jpg' /></a>

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1965 Valiant wagon Turbo slant (work in progress)
2000 Chevy 155" cargo van - The Abductor
1970 Newport convertible
1996 Buick Roadmaster Wagon
1966 CruiseAire motor home
1990 Toyota 1 ton box truck TURBO slant (scraped)

Sorry

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http://shutter12.pictures.aol.com:80/da ... EF0300.jpg

http://shutter13.pictures.aol.com:80/da ... ug0300.jpg

http://shutter14.pictures.aol.com:80/da ... So0300.jpg

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1965 Valiant wagon Turbo slant (work in progress)
2000 Chevy 155" cargo van - The Abductor
1970 Newport convertible
1996 Buick Roadmaster Wagon
1966 CruiseAire motor home
1990 Toyota 1 ton box truck TURBO slant (scraped)

I think you will just have to expeirament with this, heat and no heat.

The idea behind it is for OEM and drivabilty problems. They was not consirned with power that much.


Chances are the best way will be with no heat. After all a turbo makes enough heat to keep any fuel vaporized. You might even use it and run a sort of cheap water intercooler. Build a tank that you have a pump attacted and plum it into the intake. When your racing fill with water and add ice and pump it through the intake to cool it ( the cooler the intake, the denser the air, which = more power because its more air). And fuel in this case with it being a draw-thru setup.


If you live somewhere that there is extreme cold, then in the winter you may need to run heated water through it to keep it from icing. I doute this very much, because of the turbo and the heat it makes. WIth a little thought and pluming you could use it for both purposes, heat in the winter fro drivability and cool it when racing.



Now it may be possible, that plumming it up to heated water can still keep the intake cooler than if it had nothing. This will depend on how hot the intake gets when the turbo is boosting. You would have to just test and record temps with no water, and then with it plumed to know if this would be the case. If water can be picked up before it inters the engine, after its cooled in the radiator, it would stand a better chance of helping. Only if the intake is getting hotter than 180 should this help from a performance standpiont.

Another way of looking at it though, would be that whatever temp it would run with the heated water plumed (Ran hotter, or cooler) , it would be a more consistant temp than any other way. This might be good to start out with so that you have a more consistant temp all the time which might make tuning easier until you get a good base line tuneup. Then as you learn you can try to cool it off and add power.


Basically like I said, you will have to expeirament to find what works best.


Jess

With a one barrel I run the aluminum manifold just to get it to warm up faster. On cold winter mornings it is nice to have the heat on the floor of the intake after a few blocks which eliminates any bogging or hesitation problems. The choke comes off pretty quick too. I go from start up to 50 mph in about four blocks with good power just like an injected car.

With your set up you may not need it.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

On my draw thru turbo, I had to add water heat to the adapter between the carb and the inlet of the turbo. I found at idle the carb adapter would get cold (frosty), and the fuel would not vaporise properly, then the engine would ingest a rich slug of fuel/air. I had much better control of idle quality, with the water heated adapter. I didn't seem to have much of a problem, without the heat, at wide onpen throttle or cruise. I think the air velocity was high enough to keeep the fuel from dropping out of the air streem.

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

Good tips fellas. Think I'll go with the heat then, but I'll put a valve in there so I can shut it off, and maybe I'll get fancy and put a splitter such that I can run ice water when I feel like it. It's off to the Home Depot plumbing aisle!

Kip-on-Truckin'

_________________
1965 Valiant wagon Turbo slant (work in progress)
2000 Chevy 155" cargo van - The Abductor
1970 Newport convertible
1996 Buick Roadmaster Wagon
1966 CruiseAire motor home
1990 Toyota 1 ton box truck TURBO slant (scraped)

Turbo slant station wagon.
Not only is it way cool; it's fun to say!
Very nice!

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1975 Duster 225, same thing in a van.
Also a bunch of Neons.

Yes, much better idle and low speed operation with a little heat into that carb adaptor.
Now, if I could get better fuel mixture and boost control, may-be I can get an engine to "live" behind the turbo system I put together.
DD