V8 conversion, is it possible to keep the original front bumper completely intact? ie Not cut holes in it. Options

[billium01]

Hello,

water cooled 914 here. I have an LS6 motor I'm dropping in. Has anyone ducted a radiator successfully without cutting the front bumper? I'd like to keep the bumper intact and use a front lower valance for an intake. Was going to lay the radiator in the front trunk at an angle. Thanks!

Bill

[Coondog]

Running a 3.2, with a uncut bumper and a custom cut LE spoiler.


Renegade hybrid is who you should be asking, they make a front spoiler that is designed to scoop in the air. You could probably use the fog light grills as a additional way to hide the additional cutouts you may need to bring in extra air ???

[amfab]

Well done valence modification!

[djway]

I have heard of some LS1 swaps without bumper cut plus only the round hole area in the body was cut open to allow air in.
I have heard of 75/76 cars with v8 and bumper was not touched.
I have built a new valance for my 75 will only cut into the round hole area.

[billium01]

Thanks for the ideas and info guys. I think the front is one of the best looking parts of a 914.

[Chris H.]

Yes the Renegade Hybrids valance is nice. It's angled to direct air into the car. Although they seem to cut the bumper as well on their in-house swaps I am running it on a 3.3L 6 with no bumper cut.

RH Valance

Scroll down and you'll see it under "custom front valance".

[Chris914n6]

I use the pre-cut holes behind the valance and the bumper grilles with a little ducting. No time to dig up pics but they are posted in a thread somewhere here.

[Andyrew]

LS motors run pretty hot. I don't think you'll get enough flow or you'll put too much stress on your fan system.

It might be ok for the street and some cruising depending on your trans and if you run an electronic water pump. But I would not recommend it for any track time.

I'm pretty confident you'll have issues with your proposed setup. You could use the fog light grills for extra air inflow with some ducting, and you would absolutely need to duct the air in and out of the radiator to optimize flow.

[Chi-town]

You're the first person I've seen that says LS's run hot.

Once you get away from the standard 195 degree + emissions set up it's actually quite easy to keep them cool.

The idea I was kicking around was cutting a hole into the floor similar to what the A/C kits do and then ducting through the hood

[djway]

You're the first person I've seen that says LS's run hot.

Once you get away from the standard 195 degree + emissions set up it's actually quite easy to keep them cool.

The idea I was kicking around was cutting a hole into the floor similar to what the A/C kits do and then ducting through the hood

Does anyone have experience with through the hood ducting and the roof off of the car? I’m wondering if you feel the heat while driving.

[Chi-town]

I was planning on running two ducts closer to the outer edges of the hood to get the air to the side rather than over the top.

[Andyrew]

You're the first person I've seen that says LS's run hot.

Once you get away from the standard 195 degree + emissions set up it's actually quite easy to keep them cool.

The idea I was kicking around was cutting a hole into the floor similar to what the A/C kits do and then ducting through the hood

Does anyone have experience with through the hood ducting and the roof off of the car? I’m wondering if you feel the heat while driving.

It's more efficient. But yes the heat is noticable in the cabin at low speeds and you can feel it with your arms out the roof and sides.

[Andyrew]

You're the first person I've seen that says LS's run hot.

Once you get away from the standard 195 degree + emissions set up it's actually quite easy to keep them cool.

The idea I was kicking around was cutting a hole into the floor similar to what the A/C kits do and then ducting through the hood

My point was they typically run at 215+ but I see your point. I'm sure they are easier to keep cool than a typical SBC. But no front cutout is extremely unlikely to keep cool... There is a damn good reason the rennegade cooling system is the way it is.

I would hate to push/pull air from the ground. If you pulled air it would be really hot on a hot summer day and would probably overheat due to the super high ambient temperature of the asphalt at low speeds/idling. And if you pushed air through it then you would just dust the area around you as well as create front end lift at higher speeds.

[mepstein]

I would make the opening the way you want and see if it works for you. If it doesn’t, modify it until it does. Then paint or chrome.

[djway]

You're the first person I've seen that says LS's run hot.

Once you get away from the standard 195 degree + emissions set up it's actually quite easy to keep them cool.

The idea I was kicking around was cutting a hole into the floor similar to what the A/C kits do and then ducting through the hood

My point was they typically run at 215+ but I see your point. I'm sure they are easier to keep cool than a typical SBC. But no front cutout is extremely unlikely to keep cool... There is a damn good reason the rennegade cooling system is the way it is.

I would hate to push/pull air from the ground. If you pulled air it would be really hot on a hot summer day and would probably overheat due to the super high ambient temperature of the asphalt at low speeds/idling. And if you pushed air through it then you would just dust the area around you as well as create front end lift at higher speeds.

I had a 2002 Trans Am WS6. The had no nose opening and only a small plastic strip that stuck down only about an inch below the underside bodywork and only about two inches back. Not a large opening at all pulling air right off the road then exiting back under the car. Never had a heat issue no mater the outside temps and how I drove it. That car is also over 4500 pounds.
BigKat 83 has a small opening in the body with average wheel well exits, no ducting. LS1 and no heat issues.
Most cars the air enters the nose and exits under the car with no real lift. If you place flaps to create a negative pressure in front of a floor exit ( like the flaps in front of the motor compartment) you should create a negative pressure which would actually suck the air out the bottom and you should not really have much lift. Ducting would increase the efficiency. A low entry point actually should pull the air that the rounded valance would push under the car and should cause equal lift if not more.
Low air entry and floor exit does not to increase the distance the air travels compared to the air going under the car. The greater distance would be the necessary element in lift.

[Andyrew]

You're the first person I've seen that says LS's run hot.

Once you get away from the standard 195 degree + emissions set up it's actually quite easy to keep them cool.

The idea I was kicking around was cutting a hole into the floor similar to what the A/C kits do and then ducting through the hood

My point was they typically run at 215+ but I see your point. I'm sure they are easier to keep cool than a typical SBC. But no front cutout is extremely unlikely to keep cool... There is a damn good reason the rennegade cooling system is the way it is.

I would hate to push/pull air from the ground. If you pulled air it would be really hot on a hot summer day and would probably overheat due to the super high ambient temperature of the asphalt at low speeds/idling. And if you pushed air through it then you would just dust the area around you as well as create front end lift at higher speeds.

I had a 2002 Trans Am WS6. The had no nose opening and only a small plastic strip that stuck down only about an inch below the underside bodywork and only about two inches back. Not a large opening at all pulling air right off the road then exiting back under the car. Never had a heat issue no mater the outside temps and how I drove it. That car is also over 4500 pounds.
BigKat 83 has a small opening in the body with average wheel well exits, no ducting. LS1 and no heat issues.
Most cars the air enters the nose and exits under the car with no real lift. If you place flaps to create a negative pressure in front of a floor exit ( like the flaps in front of the motor compartment) you should create a negative pressure which would actually suck the air out the bottom and you should not really have much lift. Ducting would increase the efficiency. A low entry point actually should pull the air that the rounded valance would push under the car and should cause equal lift if not more.
Low air entry and floor exit does not to increase the distance the air travels compared to the air going under the car. The greater distance would be the necessary element in lift.

I'm happy to be proven wrong! I just know the difficulty I and many other SBC's have had keeping them cool. One of the biggest reasons for me going away from a v8 was for keeping the engine cool and a usable front trunk.

[andys]

The guiding principle for adequate air flow through the radiator, is pressure differential. If there is no pressure differential between the intake and exhaust air, you'll never attain success. As such, there are probably a few different ways to get it in a 914, and would take some experimentation.

You'll hear talk of "ram air", but that in itself will not work without sufficient management of the exhaust air. If you find a good area of low pressure, then the intake side almost takes care of itself. I chose to exit the air through the hood with a diffuser that has a raised leading edge. The intake is through the front bumper, which is probably larger than needed. I may wait until summer to tape-off the intake to see how small I can go before it affects cooling performance.

Andys

[Jacob]

Maybe you could do something similar to the factory Boxster. it would be really, really tight. I do not know for sure, just throwing out a random idea.

[JRust]

I think you would be okay. Especially with the renegade valance that ducts the air up. You just need good exit air to have the flow you need through it. I used a camaro grill & had my center completely cut out in my front bumper. I wondered if it was overkill as I cut out as much metal in the front of my car as well. In the end I was probably close to as much outlet as inlet. Not ideal but I had no problems cooling with my Renegade radiator either. I had nothing but problems before I went that route. I would try it how you like first. A lot easier to open a bigger inlet when you are cutting. Than replacing it because you went to big. Here is a link to a thread with different pics front bumper cutouts