rod to stroke

[RacerX11]

IMO a 6-71 might be a wee bit of overkill...

I'd use a M90, maybe a 112.

or

I wouldn't suggest dropping an Eaton supercharger onto anything. My choice would have to be Whipple, but for our motors, I'd use a centrifugal type. Liek a Vortech. They are pricey, but then you get a more high end oriented supercharger, it can be easily intercooled, and it can be made not visible without really looking.

So what is your recommendation this week? Our esteemed president would call you a flip-flopper!!!

Marty

[donk_316]

here check out this thread:

http://pennockssucks.saturnet.net/phpBB/viewtopic.php?t=210

[butchville]

thats the nice thing about it at half speed i still got all the boost i could ever need i expect to make the idlerpulleys out of alum an belts arn't that hard to find. plus you got them intimadated to start with.

[Anonymous]

He said it in terms of blower displacement, and I am not familiar with the Whipple displacements, or centrifugal displacements(If that's how they are categorized). Therefore I was more suggesting a displacement, not so much a model of blower.

[butchville]

yea i got one on my 455 olds an i'm running at 6k rpms at 28 lbs boost so its double the cfm of a 455 at 6k 455*3=1365 207*3=621
so i should be able to over boost at 6 grand 2.19 times 28 lbs =61.32lbs so at half speed 30# boost, go to a gear drive on the primary timing chain an reinforce the cam timing shaft should be different

[butchville]

ben sorry i quoted the wrong motor its a ford 4.6 mod motor if i can sleeve the block with 120 sleeves an an bore it . for the ford pistons their 90mm instead of 92 like the 3.4should reenforce the block for boost.

[TheProfessor]

yea i got one on my 455 olds an i'm running at 6k rpms at 28 lbs boost so its double the cfm of a 455 at 6k 455*3=1365 207*3=621
so i should be able to over boost at 6 grand 2.19 times 28 lbs =61.32lbs so at half speed 30# boost, go to a gear drive on the primary timing chain an reinforce the cam timing shaft should be different

dude are you serious about that 455

[butchville]

yea built the manifold oringed heads an bottom end girdle i built myself

[quaddriver]

If I may...I would not bore out anything GM has cast in the last 25 years past .040....and thats not me talking, thats powertrain. Too much has been removed in sacrifice to the god of weight. And coolant does not burn well. (besides, as you hone in .010 increments, the stones distort the bore because they are not themselves rigid, to get a true large overbore you have to rough bore to within .010/.005 and then hone to the right size. With the thin wall castings the boring tool will literally move the cylinders within the block a hideous amount.)

btw if anyone has Excel (2000 or better) I wrote a little spreadsheet/VB macro that lets you input stroke, rod length etc and it charts piston speeds and dwell angles etc so you can 'see' the effect....It was written for a ford 302 but all you have to do is change a variable or two. Free for the asking....

[SappySE107]

I have something like that for the 60V6, but send it on over and ill check it out. I have a ton of stuff to add to the downloads section of the site so may as well pile it on me while im in the mood.

[TheProfessor]

butchville got any pics

and quaddriver i completely agree with you

[SappySE107]

You are saying not to go over .040, when someone has gone .120 already? I dunno if I agree with either of those,as .120 is a bit much and will thin the walls more than I would care to. .040 however is half a mm walk thickness. Does anyone have the stock average thickness? I would say sonic test before you overbore any block if you want to be the safest on teh decision. Also, how is honing going to cause a shift of the cylinder? Its not a floating cylinder setup so I have my doubts that something like that is going to cause issues.

[Streetrodder83]

It's the boring tool not the hone. I think what he is saying is more of a distortion to the cylinder wall than the actual movement of the cylinder itself. That also being the idea behind torque plates. 28 lbs of boost that is one hell of a boost level. How are you keeping from detonation. Roots blowers are not known for thermal efficiency 8 psi is generally all you can squeeze out of on 92 octane and that's on 8-9:1. 28 lbs even on 7:1 will have an effective CR over 20:1. Personally, I think that 6-71 is alittle excessive on a 3.4. Being that a 6-71 will displace 411 CI of air per revolution. If your looking to go with a Weiand blower a Pro Street 142 or 177 would be a better choice.

[Gemmer]

Did you research the flow chart on that supercharger? The cam belt spins at half speed so its not going to do you any good to drive a SC off that. In fact, its bad for the cam belt to begin with (which would be custom length for the SC as well).

could always make a custom SC pully half the size =P

[butchville]

i'm going to control boost with a sionoid valve an let a computer control it with propane for fuel i should be ok as to octane it's about 112 if i remember right an the cooling effect should help also i did some more thinking { could be dangerous} an i think the way to go maybe the northstar pistons 6.0 rods would push them out the top .076 i could take that off with a belt sander lol just a shade over a 1/16 inch not a problem i got a lathe to cut them an being dished looks like i got enought metal to not have ring problem. pics of the boat i'll post when i get my camara back a friends got it right now doing some ebay stuff