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A new bullet
https://slantsix.org/forum/viewtopic.php?t=28649
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Author:  turbo66valiant [ Mon Sep 07, 2009 4:50 pm ]
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I was thinking that the Demon had the metering plate drilled for boost but maybe not. I will need to take it apart to see whats up. I had a 4.5" alcohol valve in it and that seemed to work the best on the dyno, even though we never got it down into the 12's. Also have 27 bleeds in it. When I put the PV plug in the front, there shouldn't be a problem, right? It went way rich about half throttle but pulled back into the 13-14's. I'll take the fuel system apart again to see if there was any blockage but this was done 10 runs ago. I checked the meth and it sprayed plenty out of the jet. It is surprising how much fuel flows out of a 14 gph jet, Wow. Just seems there is something simple I'm missing. Later

Author:  Shaker223 [ Mon Sep 07, 2009 5:47 pm ]
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I don't think you jetted up enough in the front when you took the PV out. I don't recall but doesn't the PV account for 10 jet sizes by itself?

On my carb, I mod'd the PV to stay closed with a spring then I drilled into the well behind the PV and referenced this to the carb hat. Now, when the hat sees boost it will open the PV (based on spring pressure). On turbo mustangs they say a 10hg pv spring will open with 5psi of boost.

This modification helped my part throttle get into the high 12/low 13s afr. Prior to this mod the afr can be seen here: http://www.youtube.com/user/Shaker223

My WOT is rock solid in the low 12.0 range with pump gas and 11.5 with race gas. I'm using a 9gph meth jet and 100% meth.

Author:  turbo66valiant [ Mon Sep 07, 2009 7:03 pm ]
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Quote:
I don't think you jetted up enough in the front when you took the PV out. I don't recall but doesn't the PV account for 10 jet sizes by itself?
You may be right Tom. I did find out that my carb hat may be in the wrong placement for the vent tubes. Its in the 10-11:00 position and they say this is one of the worst w/ a divided hat (EV).

Author:  Joshie225 [ Mon Sep 07, 2009 9:39 pm ]
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Have you extended the bowl vents into the hat? This has solved fuel delivery problems for a lot of folks by increasing the bowl pressure under boost.

Author:  turbo66valiant [ Tue Sep 08, 2009 4:36 am ]
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Quote:
Have you extended the bowl vents into the hat? This has solved fuel delivery problems for a lot of folks by increasing the bowl pressure under boost.
No, but I will be. Thanks

Author:  Shaker223 [ Tue Sep 08, 2009 6:46 am ]
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Quote:
Quote:
Have you extended the bowl vents into the hat? This has solved fuel delivery problems for a lot of folks by increasing the bowl pressure under boost.
No, but I will be. Thanks
I tried this too but my engine didn't like them...way to rich. Yours might since it seems to need more fuel.

Tom

Author:  turbo66valiant [ Tue Sep 08, 2009 12:40 pm ]
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Ordered copper gasket and o-ring tool today. Getting serious now!

Author:  CARS [ Tue Sep 08, 2009 2:46 pm ]
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Quote:
Ordered copper gasket and o-ring tool today. Getting serious now!
There goes the "safety net" :lol:

Author:  Shaker223 [ Sun Oct 18, 2009 3:50 pm ]
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Any Updates?

Author:  Dolmetsch [ Wed Oct 21, 2009 2:22 pm ]
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I have read through all the posts . Very interesting info.
I see the discussion centres on 170 or 225 cu in engines.
The 170 has a short stroke and will rev to the moon but lacks UMPH. off the line. The 225 has great torque but high RPM and a 4.12 stroke are not good things together. HoWEVER. There is the 198 which is the best of both worlds. I never had a turbo on one although i did turbo a 170 but I did build a NA engine for my wifes 66 Barracuda and was very happy with it. It ran mid 15s back in the day and she still has her trophy from Mohawk Drags strip. The stroke is short enough to keep the engine out of trouble Piston speed wise but long enough to restore the torque the 170 lacks. The 198 block will not take the big overbore the early 225 will but a 198 crank in an early 225 block will net a resonable cubed motor with a bit more safety. Just a thought but my hat is off to all you /6 turbo guys. I am more than just a little impressed with your results.
Don

Author:  Charrlie_S [ Wed Oct 21, 2009 2:56 pm ]
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Quote:
. The 198 block will not take the big overbore the early 225 will
Don
To the best of my knowledge, there is no difference between the 198 and 225 blocks.

Author:  Joshie225 [ Wed Oct 21, 2009 3:05 pm ]
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Quote:
Quote:
. The 198 block will not take the big overbore the early 225 will
Don
To the best of my knowledge, there is no difference between the 198 and 225 blocks.
Yep, while they 198 and 225 were in production together they got the same engine blocks.

Author:  Dolmetsch [ Wed Oct 21, 2009 8:24 pm ]
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Just so you know i wasnt guessing. My current slant six in my Rail is overbored to 3.56. I had a 1980 198 block sonic checked last fall. it would not even handle an 080 overbore so i scrapped it. . The engine in my rail is a 1962 block.
yes the physical dimensions are the same but the blocks were thinner by 1980. I plan to get another early 60s block and use the 198 crank.
Don

Author:  Charrlie_S [ Wed Oct 21, 2009 8:53 pm ]
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Quote:
I had a 1980 198 block
Don
198 motors were only produced from 70-74. By 1980 they were long gone.

Author:  Dolmetsch [ Thu Oct 22, 2009 1:57 pm ]
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I cant check the year now so i will just accept what you said since i sent it to scrap. All i have left is the head and the crank. Sold the rods to another slanter for his 225. The engine was given to me so i didnt pay much attention what it came out if.
Don

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