Jim,
Are you still looking for the BBC intake.
I have a raised floor(tented) BDS competition manifold for sale if you are,
Pm me, if interested
Rick
Fiat48..
How u doing? Good I hope.
You know, 13:1 doesn’t scare me for some reason, but there’s probably more to it that I don’t understand. Maybe you can shed some light.
What is it about higher static Cr that concerns most people? Wouldn’t the "final Cr", be more crucial then static?
ie, 13:1 15 pounds of boost, compared to 11:1 30pds of boost?
Which combo are you more uncomfortable with?
Rick
I'm in agreement w/ Bob here about the 1471 being a bit much for what you're wanting to do.
An 871 would work fine and produce everything you'd need in boost for some serious "feel it in the seat of your pants power" ...
and are you sure it's 13:1 or is that the ratio summit/jegs/your speed shop gave to you? I had some Ross blower pistons I used w/ some 990 open chamber heads that were supposed to be 13:1 and it came out to more like 12.2:1 by the time I cc'd the heads and added in head gaskets, etc.
I wouldn't let that scare me too much unless the motor's clearances are real tight & exact.
As far as the extra equipment needed (110 pump,offset mag, possible set back plate, etc) it's a lot of extra cash for making passes a tthe lake IMO ... save your cash for the methanol with the way it's prices are climbing.
My .02 for what it's worth,
Brian
Fiat48..
How u doing? Good I hope.
You know, 13:1 doesn’t scare me for some reason, but there’s probably more to it that I don’t understand. Maybe you can shed some light.
What is it about higher static Cr that concerns most people? Wouldn’t the "final Cr", be more crucial then static?
ie, 13:1 15 pounds of boost, compared to 11:1 30pds of boost?
Which combo are you more uncomfortable with?
Rick
Sure a guy could do 13 to 1. But like you say...how must boost could you get away with? Since boost is "breathing" and compression is "squeezing".....would it not be better to have more "breathing" and give up a little "squeezing"?
I think so.
I like 12 to 1 ...a locked out mag at 34 degrees...a decent 6 or 8/71 blower...an 80a pump and one main bypass. Simple...in fact downright easy.
And I try to build the motor as efficient to breathing as I possibly can....just like I would not have a blower....and then add the blower. That way I depend on the blower less to do what I want to do. That makes me less dependent on the blower as I don't have to drive it so hard to do the job.
If Jim does not want that manifold then please pm Morg. I think he has seen the light.
You know, 13:1 doesnt scare me for some reason, but theres probably more to it that I dont understand. Maybe you can shed some light.
What is it about higher static Cr that concerns most people? Wouldnt the "final Cr", be more crucial then static?
ie, 13:1 15 pounds of boost, compared to 11:1 30pds of boost?
Which combo are you more uncomfortable with?
Rick
Rick, have you ran 13:1 on a serious blown alcohol piece?
Jim,
It was good talking to you the other day. I have been thinking about your setup since we spoke, and I am thinking I agree with Busby and Bob. Unless you're wanting to step up to ProMod one day, a good 8-71 will be more than enough for what you want to do with the boat...plus, it would save you about $500 by not needing a mag offset.
But, since you already have the 14-71, you might as well run it. 6 of one, half a dozen of the other kinda deal. By the way, I know a guy with a nice polished Littlefield 8-71 high-helix retro blower for sale if you're interested.
Take care,
Adam
Some Of The Guys I Run With Have Tried Several Compression Combo's 11.5:1 Is Realy Ideal On Alcohol But Some Of Them Are Running 14 To 15:1 Remember Alcohol Has A Higher Combustion Rate Than Gas So Higher Compression Easier To Ignite. Especialy If You Don,t Run A Lot Of Boost Higher Compression Helps. A 14-71 Blower Really Dosn't Start To Work Until About 12lbs Of Boost Anything Under That And The Motor Will Try To Labor And Not Idell And Bog Till The Blower Starts To Spool Up And Create Boost. I Have A 612" Chevy 10.5:1 Comp. With A 14-71 Injecting Only On The Hat Right Now. The Blower Has About 2 Season On It And I'm 30% Over Making 18lbs Of Boost.
Rick, have you ran 13:1 on a serious blown alcohol piece?
Ya, running a combo right now at 13:1, 28 over on a 1471
Why do you ask?
Ya, running a combo right now at 13:1, 28 over on a 1471
Why do you ask?
I was just wondering, because I haven't heard a lot of people doing it successfully. We tried 14:1 on a blown alcohol 538 in a ProMod boat with a 14-71 and Buzzard catcher...didn't work out so well. Maybe you're just smarter than we are.
I was just wondering, because I haven't heard a lot of people doing it successfully. We tried 14:1 on a blown alcohol 538 in a ProMod boat with a 14-71 and Buzzard catcher...didn't work out so well. Maybe you're just smarter than we are.
Sounds like it.
All kidding aside, what problems did you experience?
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