ZZ454 Hood Clearance Issues
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Joined: Apr 2009
Posts: 58
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From: Lansdowne VA
ZZ454 Hood Clearance Issues
I just finished putting in my ZZ454 engine with a TKO 600 transmission and I have a clearance issue with the hood. It is a 1971 convertible and it has the Hi Rise hood on it. It wont fit over the air cleaner, its close but wont fit so my question is... The hood for the big block, is it taller than the hi rise hood you can buy?
Here is a picture of the engine without the hood...
Any experience with these hoods would be appreciated.
Thanks... Dan
Here is a picture of the engine without the hood...
Any experience with these hoods would be appreciated.
Thanks... Dan
Safety Car
Joined: Oct 2007
Posts: 3,729
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From: Austin Texas
Corvette of the Year Winner 2017
2016 C3 of Year Finalist
No stock, BB is shorter than aftermarket L88, that intake is pushing your breather up.
No Spacer/adapter under the carb. ? right ?
you will have to run a dropped breather,
I customized my own breather, and dropped it down 1.75" for Hood clearance.
No Spacer/adapter under the carb. ? right ?
you will have to run a dropped breather,
I customized my own breather, and dropped it down 1.75" for Hood clearance.
Le Mans Master
Joined: Jun 2007
Posts: 7,666
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From: Where it's always hot as Hell-South Louisiana.
St. Jude Donor '07-'08-'09-'10-'11-'12-'13
ask around about a drop base air cleaner. While I do NOT have a zz4 bb, i do have the zz4 sb in an 80 model and used a drop base a/cleaner.
Drifting
Joined: Aug 2005
Posts: 1,682
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From: League City TX
For comparison-
I have a big block with a Performer RPM intake & a Holley carb.
I am using a very dropped base air cleaner and a 3" tall filter.
It barely clears my L88 hood. You will need something thats a similar height.
The big block hood is lower.
I have a big block with a Performer RPM intake & a Holley carb.
I am using a very dropped base air cleaner and a 3" tall filter.
It barely clears my L88 hood. You will need something thats a similar height.
The big block hood is lower.
Melting Slicks
Joined: May 2005
Posts: 2,209
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From: Montgomery Alabama
Cruise-In VII Veteran
St. Jude Donor '06
Unfortunately, you will need to swap the intake to fit this motor under your hood. I have the ZZ454 with the rectangle port heads in my 72, and I am using the L88 hood and air filter assembly. It has the aluminum dual plane GM intake manifold and fits just fine. The single plane intake is over an inch taller than the GM dual plane intake.
I am ordering an Edlebrock Air Gap intake manifold and modifying the air cleaner base to fit the hood air box and filter element this winter.
I am ordering an Edlebrock Air Gap intake manifold and modifying the air cleaner base to fit the hood air box and filter element this winter.
Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
I am not sure which hood you are talking about "hi rise"... On a 71 its either a BB hood or a SB hood... neither will clear that intake.
You are going to have to run an L88/LT1 drop base air cleaner (2" drop w/3" filter). Even that air cleaner is not going to clear a stock BB hood with an RPM intake. (your Gm perf parts intake is basically a Edl RPM).
Your options:
1) Change intakes to a Torker II or old LS6.... Either one will choke the engine considerably...(or possibly find an old Street Dominator intake but i doubt its a good match for a stock 454)
2) Change to an L88 hood and use the L88/LT1 air cleaner.
Suck but....it is what it is. check out Vanacors for good quality, light weight L88 hoods relatively cheap. I just went to their L88 HI RISE (4") hood from a regular L88 hood and I am very impressed with it.
You are going to have to run an L88/LT1 drop base air cleaner (2" drop w/3" filter). Even that air cleaner is not going to clear a stock BB hood with an RPM intake. (your Gm perf parts intake is basically a Edl RPM).
Your options:
1) Change intakes to a Torker II or old LS6.... Either one will choke the engine considerably...(or possibly find an old Street Dominator intake but i doubt its a good match for a stock 454)
2) Change to an L88 hood and use the L88/LT1 air cleaner.
Suck but....it is what it is. check out Vanacors for good quality, light weight L88 hoods relatively cheap. I just went to their L88 HI RISE (4") hood from a regular L88 hood and I am very impressed with it.
Thread Starter
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Joined: Apr 2009
Posts: 58
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From: Lansdowne VA
Thanks for the picture Ironcross... what type of air cleaner do you have on the car? Dont see it in the pictures. Do you have a drop breather like everyone is talking about?
Thanks everyone for the information, I am searching around now for a dropped air cleaner so I can get this hood to fit, I cant wait to drive the car....
Thanks everyone for the information, I am searching around now for a dropped air cleaner so I can get this hood to fit, I cant wait to drive the car....
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Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
The underside {air box .... I guess that's what there called} of the L-88 hoods are off set to the right from the center-line but are made for the BB`s...and should fit yours
Oh the air cleaner'?...that got 'feets several years ago....
Oh the air cleaner'?...that got 'feets several years ago....
Instructor
Joined: Nov 2009
Posts: 128
Likes: 2
From: Leesburg VA
I have a ZZ454 in my 69 with an L-88 hood. There is only about 1/2 an inch clearance, maybe a little less. I did tons or measuring and research and found a cheap no-name air gap intake on Ebay. Even painted in the air gap area to match the car. Intake really performed well too.
Instructor
Joined: Oct 2009
Posts: 180
Likes: 0
From: Lakefield Ontario
I did the same swap in my 69 vert.
I used Ecklers L88 hood and a L88 air cleaner base,I kept the intake the ZZ454 came with and added a Holley 850 vaccum secondaries carb.
I just had to enlarge the air chamber diameter on the bottom of the hood a bit.
As a side note, I also went with a K&N air cleaner top to ensure enough air got to the carb.
I used Ecklers L88 hood and a L88 air cleaner base,I kept the intake the ZZ454 came with and added a Holley 850 vaccum secondaries carb.
I just had to enlarge the air chamber diameter on the bottom of the hood a bit.
As a side note, I also went with a K&N air cleaner top to ensure enough air got to the carb.
