174/177 supercharged small block, where to start?

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DARTGAME said:
This motor in your barracuda yet :poke: @mopardude318
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Not yet!!!! But it’s going in my ‘74 W200 with a slow shifting NP435 :/.

@RustyRatRod
Engine was on the dyno today, 510HP /508 FT LBS TQ using a 3.48” diameter upper pulley. That’s 72% overdriven. Apparently the blower wasn’t making any boost at all, the rotors were in the way, holding the engine back.
Next try is with the 2.5” pulley. Brian thinks that should make some boost, good for around 40 HP.
Stay tuned, maybe Friday I’ll have the updated numbers.
 
mopardude318 said:
Not yet!!!! But it’s going in my ‘74 W200 with a slow shifting NP435 :/.

@RustyRatRod
Engine was on the dyno today, 510HP /508 FT LBS TQ using a 3.48” diameter upper pulley. That’s 72% overdriven. Apparently the blower wasn’t making any boost at all, the rotors were in the way, holding the engine back.
Next try is with the 2.5” pulley. Brian thinks that should make some boost, good for around 40 HP.
Stay tuned, maybe Friday I’ll have the updated numbers.
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It turned that with no boost? <rolls eyes>
 
mopardude318 said:
Trick Flow , Harland Sharp rockers.
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Well chit. It might not be creating boost. I'd still double check with another boost gauge. Are you SURE you figured the drive ratio right?
 
RustyRatRod said:
Well chit. It might not be creating boost. I'd still double check with another boost gauge. Are you SURE you figured the drive ratio right?
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You have to think, boost is just a restriction in the air, from intake to exhaust.
 
RustyRatRod said:
Well chit. It might not be creating boost. I'd still double check with another boost gauge. Are you SURE you figured the drive ratio right?
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I mean. I posted that spread sheet, I was going off what I had and followed the chart. I don’t think I’m wrong. We will find more out tomorrow when we do another run. I next day aired that 2.5” pulley to be delivered tomorrow so, I’m curious to see what happens with it. :)
 
Update: the pulley worked! LOL
It produced 3 lbs of boost

579 HP
580 FT LBS

I’ll post a video and the graph later this evening.
 
mopardude318 said:
Update: the pulley worked! LOL
It produced 3 lbs of boost

579 HP
580 FT LBS

I’ll post a video and the graph later this evening.
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Hell yeah! Are you gonna try for more or play it safe?
 
MiradaMegaCab said:
What was your total timing?

Congratulations,

Now it’s time for that 671 !!
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oh man. We were talking about that, the 671 with 5 psi, turning slower would put me past the limits of a stock block. LOL I don’t think I NEED it! LOL

total timing was 35, I’ll have my BTM pull 1 degree of timing per pound of boost so that’ll be 33.
I might play it safe and run 33 deg, 30 all in with boost.

@RustyRatRod I gonna keep with what I got.

Peak was at 6200 RPM and there was no apparent blower belt slippage, so I’m happy with that.
 
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Just saw video on Instagram! Impressive! Makes me want to go 408 with my little 144. Looks awesome too.

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More boost more boost :mob:. Just messing with you that's awesome congratulations!
 
DARTGAME said:
Are you running 6 rib pulleys or 10 rib?
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These are 6. I’ll see if I can get my 10 rib system to work, once I have everything in hand. It’ll be a little bit, the 10 rib idler is on back order.
But I’ll be pulling the motor out of my truck and I’ll swap this one in. Gotta build my in tank pump fuel system for that thing.
 
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