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C

crebo

Guest
That's why I love you guys and girls. You said no question was to dumb.

Anyway,
I swapped 350 for 402 BB. My fan shroud is in pieces. Should I buy a 77 fan shroud and begin cutting? Do I really need a fan shroud? Any better ideas? Any upgrades while I'm in this situation. Already upgraded the radiator.

Guys and Girlz, any advice would be much appreciated

Thanks much Ashman
 
7

73BB

Guest
Ashman - I don't think that there are any differences between the BB & SB shrouds, you should be able to run one with no modifications. If the parts houses DO specify different shrouds then get a BB unit.

I would definately recommend installing one, especially since you live in a warmer climate and will be in traffic more than five minutes at times.

I will check my hood clearence in the morning but I'm pretty certain that I am within 2" of the hood.

Good Luck
 
C

crebo

Guest
Thanks 73BB,
I was just looking at the Ecklers catalog for the shroud. Checking options and pricing. Be cool to find a used one. It will have to slightly modified anyway.

I'm still stuck on this hood thing. I guess 73'es were made for BB installations and 77 weren't. Again when I close my hood the carb locking bolt hole is pretty much touching......
I will L-I-G it. Let It Go.
Again thanks for everything.
Ashman
 

Tom73

Well-known member
Joined
Aug 21, 2001
Messages
1,427
Location
Round Rock, TX
Corvette
73 LS4 Coupe - 04 CE Conv
crebo
My '73 BB has a different shroud then my '73 small block. So look for a big block shroud. You do need to run a shroud. A shroud and approprate seals forces the air that the fan is pulling to come through the radiator. Without a shroud the fan is just moving air around behind the radiator and not pulling air through the radiator.

The 73/74 BB vettes used a low rise intake manifold to gain clearance for the carb and air cleaner. Do not know what intake you are running but it may be too tall for your hood.

tom...
 
C

crebo

Guest
Thanks Tom,
Plan to order me a new shroud most tick. The BB and SB fan shroud's are the same price anyway. I would imagine that the BB is just a tad higher (bigger) than the SB.
Thanks much
And good looking out on the intake....

Ashman
 

Tom73

Well-known member
Joined
Aug 21, 2001
Messages
1,427
Location
Round Rock, TX
Corvette
73 LS4 Coupe - 04 CE Conv
crebo,
Check out my web site, The '73 Spot below, have pics of my small block and big block shoruds. Go to Technical Info and then Fan Shrouds. The big block uses a unique fan that has a small extension on each blade that reaches outside the shroud.

tom...
 
C

crebo

Guest
Tom73,

Pictures are awsome. They help a great deal. My shroud was cut to apparently fit the engine. I'm trying to find a good used one to clean up and mount.
Keep me in mind if you find one or hear something. Their not to expensive away.....I'll make something happen soon.
Those are some wicked blades on that BB.

Thank
Ashman
 
7

73BB

Guest
Ashman: I have approximately 1-1.5" between the hood and top of air cleaner. Which intake/carb are you going to use?

Tom73: I went and looked at the shroud pics and I have never seen anything like those blades on your BB. Mine are not like that at all, have you seen blades like that in any other car? I think that yours have been altered for some reason.

Just a thought, but I wonder how it affects the balance.
 
C

crebo

Guest
73BB,

I'm using just a stock 396 intake. I have a Holley 780 cfm. I'm fairly sure that the intake is as low pro as I can go. Maybe I'll just have to check the adjustment of my hood.

Alot of people were talking about having the engine mounted 1in lower. I never paid it any attn. I guess if I would have been able to do that-----it could have made differ.....at least a inch. Anyway
I'm just afraid that If I don't have any clearance now. The L-88 hood only has 2 1/4 over the stock hood....which still leaves me little clearance.

That is one of the reasons that I was considering the sidedraft air cleaner. It's nice looking but doesn't seem as though it would give me enough air flow. Plus noone responded with any knowledge about that device.

Anyway thanks again and those are some crazy blades (fan)
 
C

crebo

Guest
One more question?
Which shroud would work better with the cooling system and motor setup.....The pictures show the shroud away from the fan....My set-up now the shroud covers the fan completely. I heard from a self proclaimed cooling expert that the fan needed to be half under the shroud and of course the other half hanging out.
I'm wondering, since I'm buying one I would like to get the on that will benefit me the most. Plus there approx. the same price.
Later the Ashman
 
Joined
Jan 1, 2002
Messages
7,246
Location
Washington, Michigan
Corvette
'67 Marina Blue Convertible
The correct combination of shroud, fan, and clutch will place the tips of the fan blades half-in/half-out of the rear of the shroud; it was designed that way originally, as that's the way the fan is most efficient (will pull the most air through the radiator). Nothing works better than the original configuration stock system, with all the seals in place; there was very little extra cooling "margin" in the BB C3's, so the support-to-radiator, support-to-hood, and radiator-to-shroud seals and the plastic deflector under the front fascia are all essential for reliable cooling performance.
 
C

crebo

Guest
Thanks JohnZ,
Hopefully I can figure this thing out. Gonna buy all the parts soon. First things first I must buy a hood to support the air-filter. Then I'll fix the fan shroud and next I'll cure my eyesores.

Ashman
 

Tom73

Well-known member
Joined
Aug 21, 2001
Messages
1,427
Location
Round Rock, TX
Corvette
73 LS4 Coupe - 04 CE Conv
73BB said:
I went and looked at the shroud pics and I have never seen anything like those blades on your BB. Mine are not like that at all, have you seen blades like that in any other car? I think that yours have been altered for some reason.
Checked a little further. The pointed blade fans were used on the A/C equiped 454. The NCRS Judging Manual states "LS4 air conditioned cars use a fan with pointed blades that extend beyond the fan shroud with a part number 3992095." The A/C 454 used 7 blade fan while the non-A/C 454 used a 5 blade fan.

I would guess that yours is not A/C equiped.

tom...
 
S

Scott81

Guest
I don't know if this is what you are looking for but if you can't get a shroud/fan combo to work for you check into some SPAL dual electric fans if you are not trying to NCRS correctness. A good vendor is Dewitts Tom is a really nice guy and spent about an hour on the phone with me discussing aluminum radiators.
 
7

73BB

Guest
Ashman - Your hood must be lower than mine, go with the L-88.

Tom - Do you have any pics of that fan from a closer angle?
I will be on the lookout for them.

Mine is A/C equipped but the fan is not like the one pictured.

They did some strange stuff back then:Silly

Thanks
 
C

crebo

Guest
Tom,
I have factory air. Do you think it will make a difference as to the fan? Funny blades.
I've upgraded most of the cooling system. I might have started to early--- not quite knowing everything that I should. I did all of my upgrade work before I ran across Cac.

Tom73 and 73BB What type of HP/Tq are you guys pushing?
If you don't mind. Sorry if missed it one of your pages.

Thanks Ash
 

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