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iTrader: (5)

Ok I want to make my next project(down the road) a roots blown motor. I curently have a set of Vortec heads on my 350. I also have a set of good '882 castings that are ready to bolt on. What heads are yall currently running with a roots blower.

flrtin1

http://www.blowerdriveservice.com/recommend.php



http://dyersblowers.com/engine_recommendations.html

The bigger the valve size the better..... porting and polishing will help but not near as much as on a N/A engine so in the long run you have to look at your cost/HP factor......aluminum heads will allow you to run a higher static compression/ detination factor

Bottom line if its going to be a street motor you don't have to dump a ton in the heads

F-BIRD'88

The vortec heads are much much better in terms of performance. There are new vortec pattern blower manifolds ( Holley) 142ci on the market now. Should be adapable to the larger 174ci mini blower More will follow.
Holley/Weiand may have a 6-71/8.71 manifold for vortec heads ready for release. Email them and ask.
you could weld and modify a existing 6-71 blower manifold to fit vortecs raised ports and bolt pattern.

The heads are very good.. probabily worth the trouble.

Much better than the 882's.

You want a low compression ratio for a street blown motor.
You can open up ( deshroud) the chambers on vortecs quite a bit to help get the desired cr with off the shelf pistons.

882's suck.. they are the worst of the wost of the old 70's smog heads. they can be improved with full porting and larger valves.. they do have large 76cc chambers.

A ported 441 487(x) 920 or 336 is a better choice.
A true hi perf head like a ported large chamber Sportsman II is the way to go.

Of the two the vortecs are the way to go. Even if it requires modding a conventional blower intake manifold and buying custom dish pistons.
The Stock GM truck Vortec EFI lower manifold could be modified for a 6-71 blower.. Would take heavy mods thou.
But the potential is there.

flrtin1

Holley discontinued the 420 (6-71) series blower about 3 yrs ago and Weiand (Holley) has discontinued the 6-71/8-71 series sometime last summer.......there still probably are still some on the shelves but they are not making any more or supporting the current ones

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iTrader: (5)

Here is the situation and why I am asking. I read on the new vortec blower a while back and was stoked that they produced one. But the price is just too high. As I was typing this I went back to their site and saw that they only have a polished version of the blower. I emailed them and asked if they are going to produce a satin finish model. I was thinking for the price difference in blowers($1,599 old style- $2,199 vortec style) I could sell my vortec setup and get a good set of old style heads. The vortecs need bigger springs and screw in studs which shouldnt be too much. Do blower motors like smaller runners or larger runners. The tRW forged D-cup dished pistons are susposed to be 8.5-1 with 64cc heads and I had planned on going with those. It will be a roller setup ,gonna use the stock roller lifter retainers but with better lifters. Havent decided on the size of the cam . I would like to shoot for numbers close to what Holley made with their setup.

F-BIRD'88

Are you refering the Holleys new 142ci mini blower and Vortec pattern intake manifold?

Look at the dyno test in their ad. You can make this power N/A with Vortec heads.
The most you'll make with a 142ci blower is about 460 on pump gas and maybe 500 with extreme boost and Alcohol.

It only moves just so much air.

A 6-71 blower kit is near the same $$$ Same with a 8-71.

Adapting the larger 174ci mini blower to the new vortec blower manifold would be good.
the vortec heads deserve this larger blower.
easy 500++ pump gas horsepower power.

Don't know what Holley was thinking.

Holley may be working on this now. Email them and ask.

Crane Cams "Power Max" series of Cams make very good "blower cams"
they have dual pattern duration and wide LSA
Nice and "street blower friendly".
A 222-234 dur@.050 cam makes a "mild yet powerful" nice street blower cam. (6-8PSi)
A 240-250 @.050 in/ex cam is best with high boost and max street power. (10+PSi)

As far as cylinder head port volume, a Blower motor is no different than a equal N/A motor.
high flow/high velocity 170cc heads like vortecs make good power and torque to 6000rpm Big race ports will be more rpm hungry and favour larger more radical cams as a trend.
But will ultimately make more peak horsepower.
(cause they just flow more air)
Althou a blower will minimize the evils of haveing too large a port volume.

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iTrader: (5)

Oh yeah this power could be made N/A but I want something different. The mini blower is what I was talking about.

F-BIRD'88

if all you are after is 460-470 hp then the 142 will do the job.
But it is pretty well topped out for all practical purposes.
it only flows just so much air.. More then recommended blower speed starts seriously heating the air resulting in no more power even thou the boost guage is higher ( hot expanded less dense air)

These heads really deserve a larger CID blower to start with.
As long as you accept the practical power celing of the small blower, go for it.
BUTTT>>>>
If you want something just a little different than the rest
(there will many many people bolting on these new kits on vortec motors) and are willing to put in the effort, I would buy the manifold separate and a 174cid blower and adapt it to the new manifold. You'll be the only one and go like stink.
Looks to me like it's possible. the intake needs to be opened up and the larger 174cid blower bolt pattern is larger. like I said above Don;t know what Holley was thinking on this one.

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iTrader: (5)

Now I wouldnt mind going with the 174 blower but then I would just sell the vortecs and get a good set of old style heads. Do you think this is the way I should go anyways?? Because you know that nobody ever has enough HP !!! I would be happy for a while but then I would hate that I limited myself in the begining.

F-BIRD'88

Decide how much horsepower you really want.

Do you just want to simply bolt something on or do you mind doing some crafting/modifying yourself to end up with something unique.

Answer your own question for yourself. Its your project.
Like anything else, you'll get out of it exactly what you invest in it.

Build accordingly.
Shouldn't need my opinions.

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iTrader: (5)

Well I havent done much if any fabing on anything. Probably the most was making sub-frame connecotrs for my car. One advantage is that I work at a HP shop that has a dyno so I get free dyno time to run. I always like to have other opinions on things, so thanks for what you and the others have given me so far.

Havently really set a goal on the hp part yet Guess I just need to break out the Summit and Jegs catalog and surf the net for more parts combos.

Damon

Holley makes a satin finish version of the blower (non-polished) under part number 6542-1. However, it's $2200 from Summit, which is not any less than what you said you could buy the polished version for. I think somewhere you got your numbers crossed. Here's the link to this blower at Summit:

http://store.summitracing.com/defaul...h.asp&N=400178

460 HP from unported Vortecs is not likely running N/A. 400, sure. But over 450.... doubt it. Plus with the blower it's a MUCH milder combo. Big cams and high stall converters are neither needed or wanted.

With small AFR heads and a very mild flat tappet hydraulic cam I lay 390 to the rear wheels through an old TH-350 automatic (that's about 480HP at the crank with a 20% drivetrain loss factor). Agreed, somewhere around 500HP the little 142 blower is just out of "lungs." But the torque curve is like no N/A small block on the planet. 420 ft/lbs to the rear wheels (that's over 500 at the crank) at only 3000 RPMs, which is as low as I could lug it with the automatic trans. Lauching on street tires is rediculous even with a stock stall converter and 2.73 gears. Nothing but smoke anywhere below 35 MPH. Drag Radials at the very least are a necessity if you expect it to hook.

It's just a different animal than running N/A. I highly recommend you read the tech article over on Holley's website before you spec out the motor. I've proven to myself it's the truth, now that I'm on the 4th itteration of my little 142 blower motor. Here's the link:

http://www.holley.com/data/TechServi...ech%20Info.pdf

There's also an article I wrote about installing one of these little blowers in the tech articles section of this board.

flrtin1

We used those pistons in the motor I just finished for a friend of mine also the Sportsman II 64cc heads with the 200 cc runners
It hasn't been fired up yet so I can't tell ya how it runs

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iTrader: (5)

^ What blower combo did you go with? Rods,other internals.

flrtin1

Weiand 8-71..... stock rods bushed for floaters....Cam Comp Cams 12-568-4 NX284H

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iTrader: (5)

wow, just wow. Looks nice !!

JuniorOne

[QUOTE=F-BIRD'88;2697785]The vortec heads are much much better in terms

I have a chevy 350 HO deluxe engine with Vortec heads and i have a weiand 6-71 blower. I cant find an intake manifold to install it! Is there any in the market?? Or i have to make it with my own hands?? Thanks!

NoEmissions84TA

iTrader: (1)

Last post 2006 !