Engine to damn tall.

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Ripper679

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Well. Crap. Mocked up my engine with low pro 14" air cleaner and it looks like it's to tall. Hood doesn't quite close all the way. I need more room (about 1/2 inch). I guess I could remove the filter top of the air cleaner and put a non filter flat top lid on the air cleaner, that would give me the room....... but I'm wondering what a low profile air cleaner base with flat air cleaner top does to performance? (I'm making a little shy of 575hp... 351W stroker).

I was thinking of cutting the hood and putting one of those cougar hood scoops on over the top of the nasa (repo I think) hood.

Has anyone cut a round hole in their hood.... is it two layers of metal? I would probably cut a 15" round hole in the hood and pit the scoop over it with a taller air filter.

Can someone advise on what the going ons are about cutting a circle hole in the hood and bolting on the hood scoop? Does it get flimsy? Will it seperate (if it is two pieces)? Are the cougar hood scoop studs long enough to go through the hood? Will Jesus hate me if I do this?

Looking to do this (see pic)
This is COUGAR hood scoop right?

I need a beer.
 

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Well. Crap. Mocked up my engine with low pro 14" air cleaner and it looks like it's to tall. Hood doesn't quite close all the way. I need more room (about 1/2 inch). I guess I could remove the filter top of the air cleaner and put a non filter flat top lid on the air cleaner, that would give me the room....... but I'm wondering what a low profile air cleaner base with flat air cleaner top does to performance? (I'm making a little shy of 575hp... 351W stroker).

I was thinking of cutting the hood and putting one of those cougar hood scoops on over the top of the nasa (repo I think) hood.

Has anyone cut a round hole in their hood.... is it two layers of metal? I would probably cut a 15" round hole in the hood and pit the scoop over it with a taller air filter.

Can someone advise on what the going ons are about cutting a circle hole in the hood and bolting on the hood scoop? Does it get flimsy? Will it seperate (if it is two pieces)? Are the cougar hood scoop studs long enough to go through the hood? Will Jesus hate me if I do this?

Looking to do this (see pic)
This is COUGAR hood scoop right?

I need a beer.
I'm assuming you run an aftermarket intake with 575 hp. Many (not all) aftermarket intakes can have their carb pad milled. I took 1/2" off mine for hood clearance because I do not choose to run a drop base. I did have good clearance when I did run a drop base previously.
 
Yeah, that's a great suggestion, I'll keep that in mind if I decide to not cut the hood. Just a little nervous about cutting the hood as I dont want to ruin it.
 
I have a 460 and I use 2" filter with a drop base and a filter top to get the clearance needed. Just barely makes it. The filter air flow area is a little more with the 2" and filter top vs a 3" filter with a solid flat top. A 3" filter solid top has 131.94 sq inches vs 166.50 for a 2" with filter top. On the top I calculate the diameter as being 10" since there is the outer ring and inner solid center.
 
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I got this to eliminate the height of the wing nut.

https://www.summitracing.com/parts/QUL-QL-25-ACBU
I still had to cut the hood.

I had a base hood so I cut it rather than the Mach 1 hood.

Scoop is a cheap corvette scoop. I planned on making a Mach 1 looking one, but decided I wanted to drive it rather than build it.

And yes that is a pizza pan siliconed and pop riveted to the air cleaner base with insulation to seal it to the underside of the hood.
 

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I have a 460 and I use 2" filter with a drop base and a filter top to get the clearance needed. Just barely makes it. The filter air flow area is a little more with the 2" and filter top also vs a 3" filter with a solid flat top. A 3" filter solid top has 131.94 sq inches vs 166.50 for a 2" with filter top. On the top I calculate the diameter as being 10" since there is the outer ring and inner solid center.
I seem to remember some bench flow testing that showed those filter tops hurt your airflow rather than help it. The thinking is the air coming in through the top created turbulent flow, which nets you less CFM than laminar (smooth) flow. I dont know that anybody's done a similar experiment with a 2" tall circle filter.

 
I seem to remember some bench flow testing that showed those filter tops hurt your airflow rather than help it. The thinking is the air coming in through the top created turbulent flow, which nets you less CFM than laminar (smooth) flow. I dont know that anybody's done a similar experiment with a 2" tall circle filter.


Hmm - interesting. I'll have to check into it. Car runs great but it won't hurt to learn about it. If it shows that it is detrimental to performance than I might want to go back to the 3" with solid flat top. Thanks for the info.
 
I seem to remember some bench flow testing that showed those filter tops hurt your airflow rather than help it. The thinking is the air coming in through the top created turbulent flow, which nets you less CFM than laminar (smooth) flow. I dont know that anybody's done a similar experiment with a 2" tall circle filter.




One thing they didn’t mention was if you have a choke horn a drop base can really hurt flow as the distance to the top is so small that air has trouble turning into the opening. Also some chokes get fouled and can’t open fully.

Good info, though.

Engine masters just did a filter test. Green filter beat k&n.
 
Thank you everyone for the replies, and to Rcadd1ct for the pics. Looks like I'm cutting a hole in my hood. I found a deal on a 429 hood scoop.



I just need more church time to gather courage because I want the sweet baby Jesus with me when I do this.
 

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Thank you everyone for the replies, and to Rcadd1ct for the pics. Looks like I'm cutting a hole in my hood. I found a deal on a 429 hood scoop.



I just need more church time to gather courage because I want the sweet baby Jesus with me when I do this.
I measured from the hood latch to the air filter stud.

Then from the where the hood catch paint was worn and drilled a hole.

Remember the hole will be oblong to clear the filter on opening.

Also nothing says the the engine is centered in the car side to side.

Once I drilled the hole I used it to center the air cleaner lid and sharpied my initial cut line.

I set the hood back on and adjusted for opening and gap.
 

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I measured from the hood latch to the air filter stud.

Then from the where the hood catch paint was worn and drilled a hole.

Remember the hole will be oblong to clear the filter on opening.

Also nothing says the the engine is centered in the car side to side.

Once I drilled the hole I used it to center the air cleaner lid and sharpied my initial cut line.

I set the hood back on and adjusted for opening and gap.
What happens when you rev the motor and the engine torques from side to side? Not sure I see enough clearance.
 
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