Junk 350

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jeff swisher
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Re: Junk 350

Post by jeff swisher » Thu Jan 19, 2017 6:40 pm

yea the cheap GM crate engines I have no good things to say about them.
They got a bargain for where you are at. Sounds like you are doing them good also. Kudos.

The new E2514 the molly face is not even it looks like it was brushed on it looks so cheap.
The old oil expander with the plastic pucks is no longer used it is a less flattering looking ring.

The top ring does not have a dot on it no tapering anywhere on it so just stick it in whichever way you like. I do not like that idea.
Really the molly face looks horrid that is what bugs me the most.\
I talked with a machine shop here and they now use Hastings and those they say are hit or miss but they really do not like the changed sealed power ring or just get a high dollar racing ring.

That old 345NP was a tough bugger also.
The H345np or the newer 345NP is junk..Found out the hard way as I tried the "H"345np and it exploded and ruined my cam and heads and the block and crank.

So no more cast unless I find old stock.
But I do like my compression and high cranking pressures for my personal builds. 225 psi cranking pressure in my 350 that i use for work purpose.
Old 345np and old E251K in it with 11:1 compression and 268H

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Re: Junk 350

Post by KnightEngines » Thu Jan 19, 2017 8:21 pm

Well, I flowed them & was a little startled, seems this junk has some potential.

Intake
lift - before - after
.1 - 62 - 61.5
.2 - 132 - 130.5
.3 - 180 - 183.5
.4 - 214 - 223
.45 - 221.5 - 236
.5 - 223 - 239
.55 - 222 - 240
.6 - 223 - 238
.65 - 223.5 - 238
.7 - 223.5 - 239
.75 - 225 - 240
.8 - 225 - 240

Exhaust
lift - before - after
.1 -49.5 - 55
.2 - 97 - 101
.3 - 127 - 132
.4 - 148 - 161.5
.45 - 156 - 171.5
.5 - 164 - 180.5
.55 - 171 - 186
.6 - 176 - 190
.65 - 179 - 194
.7 - 179 - 196
.75 - 180 - 198
.8 - 180 - 201

Now, this is why I wasn't going to flow them, the intake port stalling above .600" could be fixed with more short turn work & likely see 245-250cfm, but I'm not at all familiar with these castings, got no idea how much metal there is to play with & have a very limited budget to play.
So I'm gonna leave it alone, 240cfm as it sits is more than I was thinking they could do, more than this engine needs & really doesn't need more time spent!

& now I am rethinking the cam, exhaust is way better then I would have thought, almost too good.

Now thinking 294/294 adv, 238/238 @ .050" on 106 centres - another crane shelf cam. Still debating that, single pattern will stomp a little harder through the mid, dual pattern will make more top end, dunno.

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Re: Junk 350

Post by KnightEngines » Thu Jan 19, 2017 8:44 pm

A quick call & we're maybe/probably gonna put a Vic jnr on this, performer would be a bit of a waste of these heads.

We'll go for the 238/244 cam, I'll try to get comp up to 10.5:1.

Revised power estimates? - I reckon it's got a shot at a little over 400hp now..........

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Re: Junk 350

Post by Carnut1 » Thu Jan 19, 2017 9:23 pm

0103161746.jpg
This pic is a 265/200 Chevy 041 2.055/1.6 or pretty close to those numbers. Some of the fuelies I had in stock with my 90's porting came right in around 235/195 and they made a very snappy head on a 355 or 383. I would think about a mild ssr cut/layback and a pinch opening. I would port the lower H on the performer and use a bigger carb. Will be a snotty little mill. Sorry for all the extra work. Youy buddie's smile will be the payback. Thanks, Charlie
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Re: Junk 350

Post by wyrmrider » Thu Jan 19, 2017 10:33 pm

Notice how Kinght does the work even on this basket case
once you get in the habit it's had to do less

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Re: Junk 350

Post by fastblackracing » Thu Jan 19, 2017 11:34 pm

Knight must be a good dude going above and beyond the budget just to hook these guys up....
its not always about the money....the satisfaction of a job well done will last long after the money has been spent!

I think you will want a bit more cam for what you are going after...I had great results on a similar build with a comp solid flat lifter deal, 248/248 108lsa..made usable power to 6700.

was similar deal lowish budget,350, air gap dual plane,10.0-1 used a vega torque converter and 4.11 gears.....I pretty much wore out a set of tires getting the 4779 750 double pumper set up correctly for the guy.

Was a fun build.

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Re: Junk 350

Post by In-Tech » Fri Jan 20, 2017 12:26 am

wyrmrider wrote:Notice how Kinght does the work even on this basket case
once you get in the habit it's had to do less
It's very hard to do it wrong when you know what's right. :)

I bet you see ~440hp @ ~6500 if that last 238/244 is close to 106 LSA and compression ratio ends up in the 10's. A bit more if you (have the balls to :mrgreen: ) spin it and have good exhaust on the dyno. :)
Heat is energy, energy is horsepower...but you gotta control the heat.
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Re: Junk 350

Post by Monza355 » Fri Jan 20, 2017 5:48 am

I also happen to have one of these "junker" 350 that i did build few months ago :lol:

It's a 9.8:1 comp 350 with stock rods and crank and forged trw flat tops.
Cleaned up and pocket ported Sportsman II heads and a victor JR intake with 950 Hp Holley
The 244/252 on 106 lsa Crane solid cam mentioned above.. with 1.6 rockers.
I'm thinking this engine might be able to make 420-440 hp with similar torque numbers and run strong to 6600-6800 rpm's

So i'm looking forward to see how your build goes Knight.
Should be very strong and fun engine for sure !!

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Re: Junk 350

Post by mag2555 » Fri Jan 20, 2017 6:30 am

To relive the stall blend off some of the bottom cut of the valve job so that it's parallel to the heads 23 degree valve inclination angle.
You may also beable to widen the floor out more at the point just after where the short turn starts and on out to the valve bowl throat.

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Re: Junk 350

Post by cjperformance » Fri Jan 20, 2017 7:25 am

Hey Tony if hes on a tight budget I have a Vic Jr gathering dust in the shop. Pretty sure the coolant passages are good, cant remember if it has had any porting, I'll check if he's interested?
With the exhaust as it is the single pattern will be great.
Should be a fun little junk beast!
Craig.

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Re: Junk 350

Post by KnightEngines » Fri Jan 20, 2017 7:52 am

Craig - we'll grab that vic jnr, no hurry, he's got to grab another bonnet to cut a hole so it can poke through. Performer will go on in the short term.

I had a little play with the short turn, with absolutely no change to flow anywhere.
It's limited by the width of the turn & bowl size.
To get more flow I'd need to get into the bowl, wall behind the turn & roof. Porting budget just won't allow that, I'm already gonna be porting for a couple of hours for free, blowing out the bowl & turn widths would add hours to the job - 230-240cfm & 1.85^" mcsa is gonna have to do. Luckily it is enough, motor will only demand about 210-220 cfm.

I'd like to get more serious with a set of these heads, these ones are only a little more than a pocket port & opened pinch. I think given the time i could pretty easy go 260cfm & max effort at 280+. There seems to be enough metal to play with.

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Re: Junk 350

Post by cjperformance » Sat Jan 21, 2017 2:58 am

No worries mate , easy, i will drag it out monday and let you know when its good to go. Just send a courier/someone to pick it up.
Craig.

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Re: Junk 350

Post by KnightEngines » Sun Jan 22, 2017 9:04 pm

I'll pick it up in person some time - been meaning to catch up anyway.

Finished the porting & CC'd the heads - 66cc, dang.
Looks like without getting too far into the valve job I can mill them down to about 60cc, which will give about 10:1 comp - will have to do.
Can't justify the cost of an angle mill.

I'll get some pics up later today once they're milled & cleaned up - they don't look fancy or pretty, rough cut & left off the carbide, very little attention to detail, good portions of the ports left with the slightly lumpy old stone finish, chambers partly as cast etc. But they'll work good for what they are & I only got 6hrs porting in them.

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Re: Junk 350

Post by cjperformance » Sun Jan 22, 2017 11:30 pm

No worries mate I'll drag it out and dust it off soon!
I'll actually be going right past your street tomorrow around 6.15/6.30pm if thats of any help? (If you're still at work at the time!)
It should be a good thing as you have it now combo/porting wise etc. More time may not get anywhere near the gain you already will have, keep it simple and good bang for buck!
Craig.

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Re: Junk 350

Post by KnightEngines » Mon Jan 23, 2017 12:22 am

I'll be here, so that'll work good!

Pics, blasted etc before work:

ImageDSC00476 by tony knight, on Flickr

ImageDSC00477 by tony knight, on Flickr

ImageDSC00478 by tony knight, on Flickr

Valve job done:

ImageDSC00480 by tony knight, on Flickr

During porting (this one's for Charlie):

ImageDSC00484 by tony knight, on Flickr

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