How to build a bullet proof 350 with 400 hp

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Basin_Runner355
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How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Wed Feb 21, 2018 8:25 am

I had some questions few weeks ago about pcv valves and carb issues. Well come to find out my #3 cylinder had soft lifter so me and a buddy of mine tore it down change the lifters all brand new. Put it back together no fire the module went out on the distributor. Put a new one got it running timed it to 34• set the rocker arms and all that. Drop it on the ground to dona stress test. Run about 75 yards on dry ground. As soon as i left off it let a good bit of smoke out the tail pipe so run it back to where the trailer is. And when i let off it lets out even more smoke look like a mosquito truck is passing it clears up if you let it idle and give it a lil gas. Let it cool off pull the plugs they are all clean except for that #3 cylindernis full of oil. Ran out of Time dint get to the bottom
Of it I’m hopping it’s just a bad valve stem seal but if i gota tear it all the ya down due to a cracked piston ring i wanna build it bullet proof with at least 400 hp.
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

One Eyed Gator
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Re: How to build a bullet proof 350 with 400 hp

Postby One Eyed Gator » Wed Feb 21, 2018 10:42 am

I know you said 350, but after my experience with Caddy's and Gen 1 350's
Get a LS2 or 6.0 truck motor and change the cam and springs and you're at your goal or over it. Have to do a lot more work to a gen 1 or 2 350 to get the same performance.

If you keep the ZZ4 I have a JB Heavy duty flex plate if you interested.

Just my 2 cents.

loudmouse
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Re: How to build a bullet proof 350 with 400 hp

Postby loudmouse » Wed Feb 21, 2018 1:59 pm

Sounds like a broke ring or ring land. Have you run a compression test on that cylinder? Was it smoking b4 you tore it apart? If not you might have a leaking intake gasket.
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Basin_Runner355
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Re: How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Wed Feb 21, 2018 3:01 pm

Loudmouse yes i did a compression test that cylinder had more compression than all the others and it was smoking before but not near that bad it just started doing it the last time i ran it before i had tore it down
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

Basin_Runner355
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Re: How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Wed Feb 21, 2018 3:03 pm

But it runs good as long as you don’t get in it it won’t smoke but if you in it for a few seconds when you let off it lets out a bunch a smoke and you can tell at high rpms it drops that cylinder cause it will go from turning a hair over 5,000 to 4,800
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

Basin_Runner355
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Re: How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Wed Feb 21, 2018 3:05 pm

Somebody told me a bad valve stem seal will do that i just haven’t gotten a chance to look into any farther my buddy that’s helping me work on it lives almost a hour away and he runs his own motor shop by time he gets home it’s dark and i gota wake up at 3:00am for Work so i can’t be up wrenching on it till midnight
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

ladyblackwater
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Re: How to build a bullet proof 350 with 400 hp

Postby ladyblackwater » Wed Feb 21, 2018 4:28 pm

Basin the number 3 cylinder has more compression because of the oil in the cylinder. If a cylinder is Fuel washed it will usally have lower compression than the rest and if it's higher than the rest that is usally because it has oil in it. X2 on what Loudmouse said. It might help if you do a leak down test to see where the problem might be coming from.
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Basin_Runner355
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Re: How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Wed Feb 21, 2018 4:59 pm

A leak down test is next on the list just haven’t gotten around to it yet
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

Basin_Runner355
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Re: How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Wed Feb 21, 2018 5:01 pm

I’m hopping for the best planing for the worst I’m just running out of mechanics who i trust all of the ones I’ve tried got some kid of deal with them I’m not fond of.
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

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Re: How to build a bullet proof 350 with 400 hp

Postby ladyblackwater » Wed Feb 21, 2018 5:22 pm

Basin I agree with you there. This is why I work on my boat myself. There isn't many mechanics/motor builders that you can trust anymore.
Greater love hath no man, than to lay his life down for a friend.

Bitterly clinging to my guns and my religion!

I am that conservative republican your momma warned you about!

Basin_Runner355
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Re: How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Wed Feb 21, 2018 6:02 pm

I’m trying to learn i just don’t have the patience to work on it one weekend a month i want it fixed so i can ride
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

loudmouse
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Re: How to build a bullet proof 350 with 400 hp

Postby loudmouse » Wed Feb 21, 2018 6:55 pm

I don't believe a valve seal would cause that much smoke. After it set for a few days and you first start it yes. Back in the day we would omit the seals because the lift we ran left no room for them :thumbleft: My bet is on the intake leaking or vacuum pulling oil out the valve cover or something similar. Now the guide could be worn slam out and yes that would cause it. Jus thinking out loud here. :scratch: can u post any pictures of the engine and setup and of the plugs? Still could have a broke ring though
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Re: How to build a bullet proof 350 with 400 hp

Postby ladyblackwater » Wed Feb 21, 2018 7:32 pm

Basin where are you located? I understand some people just don't have the time or the knowledge to do it themselves. Loudmouse I don't think it's a valve seal either. Usually it will only do that on a start up after sitting a few days like you said. My guess would be an intake leak also but I could definitely be wrong.
Greater love hath no man, than to lay his life down for a friend.

Bitterly clinging to my guns and my religion!

I am that conservative republican your momma warned you about!

Basin_Runner355
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Re: How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Thu Feb 22, 2018 5:19 am

I’m located in Lafayette louisiana. Idk how it could be a intake leak we just put that back together with all brand new gaskets and silicone the ends. This thing is driving me nuts. I’m trying to do as much as the Work as i can to save me some money but just don’t look like i have the know how.
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

Basin_Runner355
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Re: How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Thu Feb 22, 2018 5:23 am

I plan on going get my boat this weekend and pressure up the coolant system see if it holds pressure or see if it’s a head gasket. I’m at the point where i wanna pull the engine bribg somewhere and have it competly rebuilt it’s just where to bring it ismmy main concern.
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

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Slidin Gator
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Re: How to build a bullet proof 350 with 400 hp

Postby Slidin Gator » Fri Feb 23, 2018 9:01 am

If piston ring is broken you should have a bunch of blow by and oil temp would run hotter. You talked about PCV issues previously, which might match up with the blow by. Run the leak test you mentioned. Pull all plugs and turn the engine through full cycle with the leakage tester running. Leakage test kits are $40 from Northern Tool or Harbor Freight. Compare #3 vs. the rest of your cylinders. Air bubbling up in the coolant from a leakage test is a much more positive indication of a head gasket or cracked head issue vs. a loss of coolant.
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Basin_Runner355
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Re: How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Tue Feb 27, 2018 12:38 pm

Well the problem is fried piston rings my plan is to short block it and use the old block to start to build a new bullet proof 350 or 383 for down the road
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

loudmouse
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Re: How to build a bullet proof 350 with 400 hp

Postby loudmouse » Tue Feb 27, 2018 4:45 pm

Hmmmm ive never heard of or seen fried piston rings
15' Alumitech deckover LSX TT Oxbox 84" JX 4-blade
Gas required Water optional :dontknow:
Built and Tuned by Me
14'X8' JW, Chevrolet 122CID LNF Turbo Engine, Ox box, 80" NGR 3 blade

Life is short, eat your dessert first! :downtown:

Basin_Runner355
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Re: How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Tue Feb 27, 2018 7:30 pm

yea Take them out get the grease rolling use flour and mustard and a lil seasoning you know.

I had a leak down done and that’s what theycame up with has a ton of base pressure blowing out the valve cover and that it’s passin the rings
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

swamper2
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Re: How to build a bullet proof 350 with 400 hp

Postby swamper2 » Wed Feb 28, 2018 7:31 am

how many hrs were on those rings?
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Basin_Runner355
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Re: How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Wed Feb 28, 2018 10:35 am

200 hours to my knowledge but my timing was set at 34-35 degree and recently i had been playing on a hill and i was told when comming down a hill steeper than a 30 degree you oil pump isn’t getting any oil so when i put it back together it will have a oil pan with trap doors to keep the oil at the pump
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

loudmouse
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Re: How to build a bullet proof 350 with 400 hp

Postby loudmouse » Wed Feb 28, 2018 9:43 pm

Please dont take this the wrong way but I dont believe that a ring with less than several thousand hours failed (wore out) from a hill up or down. My guess was poor cylinder honing on the initial build or smoke and mirrors. My guess would be the same problem all over again after the rebuild. BTW if cylinders are in spec and old bearings are in decent condition, a re-ring and bearing job is all thats needed. Sounds like you got it figured out...
15' Alumitech deckover LSX TT Oxbox 84" JX 4-blade
Gas required Water optional :dontknow:
Built and Tuned by Me
14'X8' JW, Chevrolet 122CID LNF Turbo Engine, Ox box, 80" NGR 3 blade

Life is short, eat your dessert first! :downtown:

swamper2
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Re: How to build a bullet proof 350 with 400 hp

Postby swamper2 » Thu Mar 01, 2018 2:50 pm

If your going into it that far,,,,, stroke it
16ft alumitech/406sbc/2.38w/3-80in.R's

Basin_Runner355
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Re: How to build a bullet proof 350 with 400 hp

Postby Basin_Runner355 » Thu Mar 01, 2018 4:26 pm

I sure hope that’s all that is needed I’m not looking to put a buncha money in this thing. My future plan is to over the next year is to get a rock solid ls motor built and it don’t have to put out no more than 450 hp. I’ve been doing a lot of research and ls motos are leaps and bounds better than fist gen motors and it don’t take much but a cam swap and some head work to easisly hit 450 mark.
14ft diamond back mild zz4 355sbc pushin 410 hp 430 TQ 2:1 belt drive reduction with a 78 water walker falcons pitched at 5200

swamper2
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Re: How to build a bullet proof 350 with 400 hp

Postby swamper2 » Fri Mar 02, 2018 8:52 pm

keep us in the loop. good luck.
16ft alumitech/406sbc/2.38w/3-80in.R's


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