502bbc or 400sbc what one should i drop in????
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From: Ne, north platte
Car: 78 vett 450hp 4 speed
Engine: L88 450hp
Transmission: 4 speed
502bbc or 400sbc what one should i drop in????
all right guys i need info i have access to a 400 and a 502 the question is i have a 5 speed car with the machanical clutch not a hydrolic. if i go bbc can i even use the tranny???? and what kind a trouble am i looking at with the 502 install??? any helps welcome
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: 502bbc or 400sbc what one should i drop in????
A 502 BBC is the same as any other short deck BBC installation. There's a sticky at the top of the forum explaining a BBC swap. It doesn't matter if it's a 396 or a 540, the swap is all the same. Getting bigger than 540 and you normally use a tall deck block. That makes the swap a little more difficult.
The 400 is just another SBC. It has the same external dimensions as every other SBC so it's a direct swap.
The 400 is just another SBC. It has the same external dimensions as every other SBC so it's a direct swap.
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From: Ne, north platte
Car: 78 vett 450hp 4 speed
Engine: L88 450hp
Transmission: 4 speed
Re: 502bbc or 400sbc what one should i drop in????
A 502 BBC is the same as any other short deck BBC installation. There's a sticky at the top of the forum explaining a BBC swap. It doesn't matter if it's a 396 or a 540, the swap is all the same. Getting bigger than 540 and you normally use a tall deck block. That makes the swap a little more difficult.
The 400 is just another SBC. It has the same external dimensions as every other SBC so it's a direct swap.
The 400 is just another SBC. It has the same external dimensions as every other SBC so it's a direct swap.
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From: Tiffin OHIO
Car: 1987 Iroc-z Convertible
Re: 502bbc or 400sbc what one should i drop in????
big block is more work but also more fun. unless the 400 is really worked over then it is lighter but there is no replacement for displacement if you go with the big block use a th400 tranny or get the stock rebuilt using better stuff internally
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From: Saskatoon, SK, Canada
Car: '83 Z28, '07 Charger SRT8
Engine: 454ci, 6.1 Hemi
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Re: 502bbc or 400sbc what one should i drop in????
You can use the 5-spd, but its going to be a time bomb.
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From: Ne, north platte
Car: 78 vett 450hp 4 speed
Engine: L88 450hp
Transmission: 4 speed
Re: 502bbc or 400sbc what one should i drop in????
will 305 heads bolt up to the 400 anyone know if they will????????
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From: Ne, north platte
Car: 78 vett 450hp 4 speed
Engine: L88 450hp
Transmission: 4 speed
Re: 502bbc or 400sbc what one should i drop in????
what do i need to do to the tranny or what tranny do i need for the 502
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From: Orlando
Car: 1991 Camaro Z28
Engine: 357, Canfield heads, solid roller,
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From: Saskatoon, SK, Canada
Car: '83 Z28, '07 Charger SRT8
Engine: 454ci, 6.1 Hemi
Transmission: TH350, A5
Axle/Gears: 2.73 posi, 3.06 posi
Re: 502bbc or 400sbc what one should i drop in????
Aside from smaller chambers and valves, the heads are no different than what the 400 came with. The ports are the same size and in the same place. And bigger valves can be installed.
That said, he is right though.... a 400 needs more airflow than a factory head can really provide - you'd be wise you use an aftermarket head around 200cc or so to get the best result with the small block.
I still say go with the BBC though. If you want a manual trans then a T56 would be the best way to go (and LT1 setup will bolt right up, but you need a special flywheel to use a T56 with a BBC). If you want to go with an automatic, any of the usual GM autos would be fine... 700R4, TH350, TH400. I'll be using a TH350 with my 454 in the spring. GM used all 3 of those autos behind their BBCs.
That said, he is right though.... a 400 needs more airflow than a factory head can really provide - you'd be wise you use an aftermarket head around 200cc or so to get the best result with the small block.
I still say go with the BBC though. If you want a manual trans then a T56 would be the best way to go (and LT1 setup will bolt right up, but you need a special flywheel to use a T56 with a BBC). If you want to go with an automatic, any of the usual GM autos would be fine... 700R4, TH350, TH400. I'll be using a TH350 with my 454 in the spring. GM used all 3 of those autos behind their BBCs.
Last edited by Air_Adam; Apr 11, 2010 at 01:50 PM.
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From: Tiffin OHIO
Car: 1987 Iroc-z Convertible
Re: 502bbc or 400sbc what one should i drop in????
that is true the 400 is alright with better heads the 305 heads weren't that great with 305 more or less with more cubes. I would at least use vortec heads but bowtie heads are a better choice and not alot of money when you find them.
Re: 502bbc or 400sbc what one should i drop in????
the 305 heads would need steam holes drilled as for the bbc i just did a sbc to bbc swap as a matter of fact i just got it started for the fifst time about an hour ago the swap was simple a little more time consumeing than a small block
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From: Ne, north platte
Car: 78 vett 450hp 4 speed
Engine: L88 450hp
Transmission: 4 speed
Re: 502bbc or 400sbc what one should i drop in????
well i am going 400 small with a tpi set up might be fun lol
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From: 18326
Car: 86 Iroc
Engine: Soon to be LS 6.0
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Re: 502bbc or 400sbc what one should i drop in????
Remember to drill steam holes in the heads or else your 400 will overheat.
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