Does the "Big Mouth" front dam work?
Thread Starter
1st Gear
Joined: Aug 2016
Posts: 1
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Does the "Big Mouth" front dam work?
I am running a '89 TPI track car, and we're getting it dialed in. As usual, the faster we go, the more problems we uncover. We had an overheating episode last weekend, and I am wondering if the "Big Mouth" air dam mod really works? We have lowered the car overall, and I'm also wondering if the lower stance negatively affects the stock airflow.
Melting Slicks
Joined: Sep 2008
Posts: 2,376
Likes: 111
From: Cherokee National Forest TN
Suggest an oil cooler on a track car sustained rpm's over 3K will cook the oil. You need a good oil pan with extra capacity & trap doors a stock pan with 4 qt capacity = air in the bearings during hard braking when the oil runs to the front of the pan. If your analog aftermarket gauge shows lower oil pressure while braking you know why.
Always turned the water pump 30% slower via pulley sizes + used a vane pump rather than a paddle wheel pump = no cavitation.
Tune water flow with restrictors in the t-stat housing pic here:
https://www.summitracing.com/parts/mor-63440
Add an angled "blade" to the lower valance for more rad air. 6011 aluminum sheet is soft & will bend 90* without cracking.
Luck with your track car.
Always turned the water pump 30% slower via pulley sizes + used a vane pump rather than a paddle wheel pump = no cavitation.
Tune water flow with restrictors in the t-stat housing pic here:
https://www.summitracing.com/parts/mor-63440
Add an angled "blade" to the lower valance for more rad air. 6011 aluminum sheet is soft & will bend 90* without cracking.
Luck with your track car.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Tech Contributor
Joined: Oct 2008
Posts: 3,729
Likes: 190
From: Custer, WI
Suggest an oil cooler on a track car sustained rpm's over 3K will cook the oil. You need a good oil pan with extra capacity & trap doors a stock pan with 4 qt capacity = air in the bearings during hard braking when the oil runs to the front of the pan. If your analog aftermarket gauge shows lower oil pressure while braking you know why.
Always turned the water pump 30% slower via pulley sizes + used a vane pump rather than a paddle wheel pump = no cavitation.
Tune water flow with restrictors in the t-stat housing pic here:
https://www.summitracing.com/parts/mor-63440
Add an angled "blade" to the lower valance for more rad air. 6011 aluminum sheet is soft & will bend 90* without cracking.
Luck with your track car.
Always turned the water pump 30% slower via pulley sizes + used a vane pump rather than a paddle wheel pump = no cavitation.
Tune water flow with restrictors in the t-stat housing pic here:
https://www.summitracing.com/parts/mor-63440
Add an angled "blade" to the lower valance for more rad air. 6011 aluminum sheet is soft & will bend 90* without cracking.
Luck with your track car.
Melting Slicks
Joined: Sep 2008
Posts: 2,376
Likes: 111
From: Cherokee National Forest TN
Suggestions posted are based on empirical oval track data & may not pertain to road course racers.
Your mileage may vary.
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I will second an oil cooler. When my car was a stock street car, and I was in college and poor, I used just a simple cheap Summit brand cooler maybe 10" by 10" and a sandwhich adapter between the block and oil filter. I didn't even have AN fittings, but hose barb and hose clamps. Cheap. After that I could run the car all day and the needles would never leave the middle range of the gauge, both oil and water temp. I also drove mine on the street and would have to cover the oil cooler with a piece of cardboard in the cooler fall months because it ran too cold to burn off moisture on the street.
Melting Slicks
Joined: Jan 2008
Posts: 2,054
Likes: 120
From: AZ
The BeCool engineering support told me that coolant needs to stay in both the engine/radiator to absorb/dissipate the heat. This is why a no-thermostsat approach is wrong. Coolant flow can be optimized with a variable insert, or as they suggested, various oriface sized washers. Thermostats act somewhat like a switch, opening and closing, responding to variable excess heat from the engine's variable workload.
I found the standard Stant to have a too-small oriface for my midified engine, after throwing aftermarket WP and radiator at it. The solution was more wter flow, achieved in my case with a relatively low-dollar approach: a Robt. Shaw, as a Vette pal did. Some drill 2 or 3 holes in the thermostat to increase flow.
It is an adjustment in restriction to allow the coolant to be effective.
I like the strength the Big Mouth brings to the lower front of my car, not really needing any increased cooling air. Making a similar part wouldn't be difficult with its straight bends.
I found the standard Stant to have a too-small oriface for my midified engine, after throwing aftermarket WP and radiator at it. The solution was more wter flow, achieved in my case with a relatively low-dollar approach: a Robt. Shaw, as a Vette pal did. Some drill 2 or 3 holes in the thermostat to increase flow.
It is an adjustment in restriction to allow the coolant to be effective.
I like the strength the Big Mouth brings to the lower front of my car, not really needing any increased cooling air. Making a similar part wouldn't be difficult with its straight bends.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
I've run cars w/no stat and the barely got above 100*F. You experienced a similar thing; restricted flow caused it to run hot...you increased flow and observed better cooling, right? Sooo....
Also the T_stat is not like a switch. It is not I/O. It is variable and can regulate coolant flow in an infintely variable way from fully closed to fully open. Obviously, once fully open it can not longer influence anything in the cooling system and flow is regulated by the water pump speed and specs, and cooling is regulated by system capacity and engine BTU output.
.
Last edited by Tom400CFI; Sep 28, 2017 at 12:43 PM.
Melting Slicks
Joined: Jan 2008
Posts: 2,054
Likes: 120
From: AZ
Yup. The RS replacement flowed more. The point here is exactly that, not to throw mega-bucks at the issue when the solution may be simple and cheap.
Pardon me. It's a variable switch, rather like a rheostat. Never did I mean to aver totally On/Off, but this is all off the OP's question, isn't it.
Pardon me. It's a variable switch, rather like a rheostat. Never did I mean to aver totally On/Off, but this is all off the OP's question, isn't it.
Last edited by whalepirot; Sep 28, 2017 at 09:24 PM.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
