xterra KD24DE engine intake manifold modification

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FergO2k
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Re: xterra KD24DE engine intake manifold modification

Post by FergO2k »

Great pics Alvin. (Herb Petty's '66 and Ken Pletchers '69, I think)
Note the stock manifold has a heat shield. The tube headers might require one of these either on the headers or "loose skinning" the brake reservoirs, as it is hard to tell from the angle but they look kinda close. (could boil the fluid during heat soak, which is usually not when driving but when you pull in for gas and there is no more air flow thru the engine bay)
The 302 V8 roadster had a "gravel excursion" once and tore off the front air dam. All fine, we picked it up and went on, but next thing you know, engine temps are climbing. Turns out the air dam made a negative air pressure under the car that sucked out the heat. Once riveted back on (there might have been a zip tie in play, but I ain't telling) the car went back to running cool when pushed. (which was always when Eric drove)
Fergus O
69 2L, SUs (driver, not susceptible to polish)
02 Tacoma 4 door (sold at 300k miles!)
2017 Honda Ridgeline (2021 purchase)
Los Alamitos, CA
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jhayden
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Re: xterra KD24DE engine intake manifold modification

Post by jhayden »

FergO2k wrote: Tue Feb 27, 2024 8:29 am The 302 V8 roadster had a "gravel excursion" once and tore off the front air dam. All fine, we picked it up and went on, but next thing you know, engine temps are climbing. Turns out the air dam made a negative air pressure under the car that sucked out the heat. Once riveted back on (there might have been a zip tie in play, but I ain't telling) the car went back to running cool when pushed. (which was always when Eric drove)
So, Ferg, was the extra open hood scoop:

https://www.youtube.com/watch?v=iaexRXNLPuI

also necessary to avoid overheating?

Jon
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FergO2k
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Re: xterra KD24DE engine intake manifold modification

Post by FergO2k »

Good point. That was more about engine vertical clearance and fresh air, but I am sure it helped along those lines.
Probably helped with heat soak, as then there was a free opening at the top.

Who was the 1600 racer, orange car..... Dang, can't remember his name. MidWest region.
He would start the race with hood closed, once he got out of sight of starters he would pull the hood cable so the hood popped up on the manual release, to let out hot air.
Each time he finished they would come say "you know your hood was popped up for part of the race", and he would shut it and say, "dang, I will keep an eye on that." Since we are forward opening / rear hinged, it was never a big deal.
Fergus O
69 2L, SUs (driver, not susceptible to polish)
02 Tacoma 4 door (sold at 300k miles!)
2017 Honda Ridgeline (2021 purchase)
Los Alamitos, CA