Edelbrock BB fitment help
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Pro
Joined: Nov 2004
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From: Nice Lake Ontario
Edelbrock BB fitment help
Anybody know if an old C-427X Edelbrock aluminum intake will fit under the regular BB hood??
Is it a decent intake? I think I'll buy it anyway just to lighten up the nose seeing as all I have is a non original cast achor intake IF it will fit ?
Is it a decent intake? I think I'll buy it anyway just to lighten up the nose seeing as all I have is a non original cast achor intake IF it will fit ?
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Joined: Mar 2002
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From: Southwest MI
It's virtually the same height as the GM 069/163 intake.... fits fine on a C2, but on a C3 it would take the L-88 hood setup.
It came in "427" and "427X" the X is the open plenum version..... so expect reduced low end power, and more ~4000-4500 and above (on a std CID BB).
The casting has significantly more runner volume than the GM piece, I've been playing with them (427X) on the flow bench in an attempt to come up with a high flow period-correct looking intake for a my 66 (496 on the way in), so far the intake looks great, a little porting, a little welding, it'll be matted with a set of CNC'd 325 AFRs and a Holley 1000HP. Just what the Dr. ordered........
So....... 1) on a C3 you'd need a L-88 hood, and 2) it's a high RPM intake on a 427/454 (and it kills some low end power, thank god, lol).
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Joined: Mar 2002
Posts: 3,780
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From: Southwest MI
right, that's why GM designed the C3 low profile BB intakes
here, this pic should help.........
PS: I just remembered, the carb pad is "ranked forward" a bit more than the GM high rise BB intake..... as i recall the average C-427, front and rear measurements, are ~ the same as that of the GM. if someone is really interested, I could measure both, i have a some L-88/ZL-1 & L-72 intakes here as well (but no C3's at the moment, sorry)
here, this pic should help.........
PS: I just remembered, the carb pad is "ranked forward" a bit more than the GM high rise BB intake..... as i recall the average C-427, front and rear measurements, are ~ the same as that of the GM. if someone is really interested, I could measure both, i have a some L-88/ZL-1 & L-72 intakes here as well (but no C3's at the moment, sorry)
Last edited by 66427-450; Jun 10, 2007 at 11:50 AM.
Safety Car
Joined: Mar 2002
Posts: 3,780
Likes: 442
From: Southwest MI
That said, I measured a GM intake, and an old Edelbrock C-427X, basically, the same height, the GM was 27 thousands higher (Ave of front and rear measurements)....... probably within manufacturing tolerances (i.e. looks like Edelbrock used the same height limitations as GM)
I placed a straight edge on the carb surface and measured the distance from the front and rear manifold seal/gasket surfaces to the straight edge
GM front = 4.188 rear = 5.625
C427X front = 4.380 rear = 5.381
(looks like GM had more rake, i remembered one did, lol)
I had tried a new Edelbrock RPM a few years ago, it was a bit (~3/8"?) higher than the L-72/L-88, if I remember correctly, don't quote me re that
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The C-427's and C-454's are neat. I've run them on several deals and had good luck with them. I recently saw a back to back test on a 650+ HP 496 pump gas motor. They ran it with a C-454 and a Dominator against an RPM Air Gap with a 2" spacer to mate the Dominator to it. Virtually identical HP/TQ and curves. I wonder how the C-454 would have liked the 2" spacer?
That being said, they also changed to a more aggressive cam and a Vic Jr intake and were up 30 hp. But it wasn't a pure test, so no telling what helped the most?
I have a C-454 that I'm going to play with again one of these days.
JIM
That being said, they also changed to a more aggressive cam and a Vic Jr intake and were up 30 hp. But it wasn't a pure test, so no telling what helped the most?
I have a C-454 that I'm going to play with again one of these days.
JIM
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From: Graceland in a Not Correctly Restored Stingray
The reason I asked is that I've decided to dig out my old C-454 to put on the solid roller 496 I'm building up, and plan to fab a proper air box to mate that and a BG 1095 VS to my L88 style hood. The info helps. Thanks, 66427-450!
