Super charger on 454
#41
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How long would those motors last towing 5000 lbs, uphill, in 4th gear, at 4000rpm at all times? That's basically what a boat motor does.
Gary
Gary
Ok sorry to jack the thread but i need some clarification.
I work for a Performance shop, we do tuning/performance fabrication on modded v8s all the time. now im not familiar with this 177 blower you all are refering to so this may be where im being thrown off.
I know on the small block v8s we have fun with as well as v6s and i4s compression ratios can be anywhere from 9.3-10:1 and we can run 8-15psi on the motors no problem. now this is with turbos im more of the turbo guy and my partner is the s/c guy and tuner.
so basically just to name a few cars we have done.
99 v6 mustang COMPLETLY stock motor, 9.36:1 comp ratio. we twin turboed it with EVOIII Big 16g's running 17lbs of boost, a motor that normally creates 160's to the wheels, with this kit made 450hp/475tq @ 17psi and ran 10.9@127
01 Sunfire with an 04 2.2 dohc ecotec swap, once again completly stock motor, single turbo t3/t4 t04e 57trim .63 stg III exhaust. dynoed n/a 132hp, with 8lbs of boost did 227hp/220tq, we never got to run it at the track because previous to the turbo 3rd gear syncro was going bad and finally went the day before track day we were expecting to be in the 12s with traction :-D (dont laugh at the car, we love the looks on v8's faces when we walk past them)
ok so with that in mind. those were bone stock motors. why are you all limiting this setup to 3psi? its just not making sense to me, now im not saying run 20psi. but whats wrong with 6-8psi on this setup?
i only know about automotive performance and i know there are somethings that change when it gets into marine setups so please correct me where im wrong cuz this is very insteresting stuff.
I work for a Performance shop, we do tuning/performance fabrication on modded v8s all the time. now im not familiar with this 177 blower you all are refering to so this may be where im being thrown off.
I know on the small block v8s we have fun with as well as v6s and i4s compression ratios can be anywhere from 9.3-10:1 and we can run 8-15psi on the motors no problem. now this is with turbos im more of the turbo guy and my partner is the s/c guy and tuner.
so basically just to name a few cars we have done.
99 v6 mustang COMPLETLY stock motor, 9.36:1 comp ratio. we twin turboed it with EVOIII Big 16g's running 17lbs of boost, a motor that normally creates 160's to the wheels, with this kit made 450hp/475tq @ 17psi and ran 10.9@127
01 Sunfire with an 04 2.2 dohc ecotec swap, once again completly stock motor, single turbo t3/t4 t04e 57trim .63 stg III exhaust. dynoed n/a 132hp, with 8lbs of boost did 227hp/220tq, we never got to run it at the track because previous to the turbo 3rd gear syncro was going bad and finally went the day before track day we were expecting to be in the 12s with traction :-D (dont laugh at the car, we love the looks on v8's faces when we walk past them)
ok so with that in mind. those were bone stock motors. why are you all limiting this setup to 3psi? its just not making sense to me, now im not saying run 20psi. but whats wrong with 6-8psi on this setup?
i only know about automotive performance and i know there are somethings that change when it gets into marine setups so please correct me where im wrong cuz this is very insteresting stuff.
#42
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Be careful about thicker head gaskets. If you open up the quench area in the cylinder, it can cause detonation. That's bad on a superharged engine, Mmmmmkay?
There are a lot of people on this forum with more knowledge than me on this, so check around.
There are a lot of people on this forum with more knowledge than me on this, so check around.
You could also add a thicker head gasket to drop compression some more, I think Flatout makes a thick copper head gasket that could drop you CR by a point or more. I have never used them, so I have no idea on if they are any good. The forced air from the blower might make up for some of the inefficiency of the larger gasket
#43
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A thicker head gasket won't lower the CR that much. I can tell you that milling rect port heads .030 will increase CR on 454 by about a .25 point. So going to a .060 cometic or similar will drop it just slightly.
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I put a 174 b&m blower and a 800cfm on a 454 with 8.75 comp ratio and 28 deg timing and the boat ran great. I would not go over 9.00 . But who knows we never turned our big blocks over 4500 and look where we are at today.
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Anyone have a line on some v-6 modules? Sounds like it would be wise.
Jlo- I have a chart from the weiand site that says 12:1 should be max compression run on this 177, BBC application. For me with 9.5:1 that is close to 4psi boost. I would suspect the reason you get away with more boost concerns rod angles and geometry of the short block. Not to mention what rdoactive says about loading. The engines you build are probably a much short stroke with much less rod angles and therefore they handle the boost/detonation better, and they are at idle loading a high percentage of thier lives.
I'm plug the compression numbers tomorrow at work although I am not tearing the top of these engines now. Just curious of the drop in compression I could get. My quench is tight now, just like I like her, eerr I mean it
Jlo- I have a chart from the weiand site that says 12:1 should be max compression run on this 177, BBC application. For me with 9.5:1 that is close to 4psi boost. I would suspect the reason you get away with more boost concerns rod angles and geometry of the short block. Not to mention what rdoactive says about loading. The engines you build are probably a much short stroke with much less rod angles and therefore they handle the boost/detonation better, and they are at idle loading a high percentage of thier lives.
I'm plug the compression numbers tomorrow at work although I am not tearing the top of these engines now. Just curious of the drop in compression I could get. My quench is tight now, just like I like her, eerr I mean it
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yah rdoactive that is what i thought about today at work, it was the only thing that made logical sense to me.
blue thunder: i looked through the posts again, and didnt see the details, this motor has all forged internals? when i think of a built motor that is the first thing that comes to mind, but i didnt see that your wrote that in when you were talking about your built heads so i was just curious!
blue thunder: i looked through the posts again, and didnt see the details, this motor has all forged internals? when i think of a built motor that is the first thing that comes to mind, but i didnt see that your wrote that in when you were talking about your built heads so i was just curious!
#47
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You could probably enlarge the bowls on the heads and use a thicker gasket and reduce the CR to a little more than 9.0:1.
For V6 modules, keep a look out on ebay. They are on there from time to time in new and used.
For V6 modules, keep a look out on ebay. They are on there from time to time in new and used.
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yah rdoactive that is what i thought about today at work, it was the only thing that made logical sense to me.
blue thunder: i looked through the posts again, and didnt see the details, this motor has all forged internals? when i think of a built motor that is the first thing that comes to mind, but i didnt see that your wrote that in when you were talking about your built heads so i was just curious!
blue thunder: i looked through the posts again, and didnt see the details, this motor has all forged internals? when i think of a built motor that is the first thing that comes to mind, but i didnt see that your wrote that in when you were talking about your built heads so i was just curious!
No, not forged. Hyper pistons, steel cast crank and forged rods. I realize the risk here. If tune is off forged dies too, it just gives more room for error before trouble starts. I plan to be very conservative.
#49
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The Hyper pistons can't handle the heat. Change them now or change them and a lot more later.
Thats the main problem with supercharging the 496ho and the main reason for failure. They are running less compression than you, and are still having problems with 3.5# of boost.
Thats the main problem with supercharging the 496ho and the main reason for failure. They are running less compression than you, and are still having problems with 3.5# of boost.
#50
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Change the pistons to some forged flat tops or you engine will not last.
I put a 177 on a 330 and it lasted about 50 hours before 3 pistons melted the rings into the lands…
I have a bud with a 1995 525SC that runs like a top! 1 rebuild in 12 years, god knows how many hours on that thing…
Rebuild it right or leave it NA…
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Patrick
Patrick