Thinking teardown

Schurkey · Jun 8, 2024

Anchor said:
for sure the pistons are marked 0.40

However they're marked, they'd have to be .040, not .40.

.40 would be close to half-an-inch.

Anchor said:
Wondering if the trans bolts to block were causing vibration that I was mistaking for miss?

Unlikely. But loose bolts can't be good; and I've been wrong before.

Anchor said:
I will look for paint on converter. Didn't realize alignment was critical on converter to flex.

Best practice is to retain the factory alignment. That obviously can't happen when the flexplate or the converter has been replaced. In the real world, it shouldn't matter.

thinger2 · Jun 8, 2024

Anchor said:
Hello Thinger; As to the stuck valve, when I trailered the truck home it had no exhaust on it beyond the exhaust manifolds. I hooked the crossover back up and cobbled a muffler on it for noise. Next I did a compression test. 0 lbs in #8. All the rest good. I pulled the passenger side valve cover and started engine and the valve was down and did not move with the cam rotation. I loosened it and pulled out the push rod to inspect. Not bent. When I re-installed it the valve functtioned again. I wondered if prev. owner had maybe tightened the rocker against the valley instead of in the lifter. After pulling it apart I doubt this due to the tiny hole for pushrod. It has never stuck again, that I know of, but I have been dealing with what I perceive as a miss at road speeds. Not at idle. I plan on taking the heads to machine shop this week for exam. I mic'd the cam today, with a cheap digital tool and 1.52 accross the board. Roller lifters look good. Will look carefully at the rockers per your comment on same. Since the rest of the valve train turned out to be Comp Cams the double springs quite possibly are too. I was surprised that when the valve was stuck I didn't detect any noise. I would have thought the roller lifter would be slapping around in the bore and contacting something. Maybe just my old ears. I would never have purchased all of these performance parts but since they are here I would rather get it running and use them. I plan to call comp cams tech on Monday and see if the cam installed would require a new prom card. As to your remark on the studs, when I removed the rockers I have never had the rocker adjusting nut take so much pressure to remove. Better than loose I know but very hard with a 3/8 ratchet. Thanks for your response. I appreciate your input.

You might have a rocker stud pulling out .
Sometimes when valve geometry keeps getting more wierd it might be the rocker stud getting loose.
Or a crack in the rocker
That can be hard to track down because it only happens during the heat/ cool cycle.
Are you running a two part or dual valve spring setup?
Is the small spring seated?
Is the large spring broken?
I think you need to take another look at that stuck exhaust valve before you do anything else.

Anchor · Jun 9, 2024

thinger2 said:
You might have a rocker stud pulling out .
Sometimes when valve geometry keeps getting more wierd it might be the rocker stud getting loose.
Or a crack in the rocker
That can be hard to track down because it only happens during the heat/ cool cycle.
Are you running a two part or dual valve spring setup?
Is the small spring seated?
Is the large spring broken?
I think you need to take another look at that stuck exhaust valve before you do anything else.

Thanks again. Heads will go in( to the shop early in week.) I've got questions for comp cams and Scat tech people. Am also wondering about my stock prom card with this valve train. I have looked over roller lifters pretty closely but am a little paranoid to give them a clean bill of health. Rockers I will inspect with magnification tomorrow. I put a spring compressor on the valves today and none of them feel weak. No obvious broken springs. Thanks again for your input.

Anchor · Jun 9, 2024

Schurkey said:
However they're marked, they'd have to be .040, not .40.

.40 would be close to half-an-inch.

Unlikely. But loose bolts can't be good; and I've been wrong before.

Best practice is to retain the factory alignment. That obviously can't happen when the flexplate or the converter has been replaced. In the real world, it shouldn't matter.

Thanks. Sure glad I'm not a young guy that needs this thing to get to work in the morning.

Anchor · Jun 10, 2024

It turns out that I really needed a tear down to find out what I had. Thank you to those of you who have responded to my post and been helpful. Should I start a new post now that I have some answers? Here is the situation as it stands. The engine does not have enough miles on it to be dirty. As I mentioned earlier over 190lbs compression in all cylinders. 383 stroker with comp cams 08-500-8 hydraulic roller cam. Scat crankshaft and rods. Stock prom card in ecm? Can't not be a problem I think. Now, since I didn't have to buy all of these parts I am thinking the swirl port heads got to go along with factory exhaust. It had an older Holley 670 tbi on when I got it and it dumped fuel so I put on a stock tbi unit. I'm not in a big hurry and need to research heads and intake as well as bigger injectors. With all of the other parts already here I can't see not completing and chipping. Boy is this project in flux. Not too fond of the fact I will probably have to burn 82 octane but it is bearable.If you guys want to chip in with ideas I am all ears. Also if you think I should make a whole new post to get more ideas let me know. I'm not dying to spend money on it but we already think the stock heads need work. I could apply that to new heads. My how these projects have a way of growing! Thank all of you

Schurkey · Jun 10, 2024

Anchor said:
Should I start a new post now that I have some answers?

NO. Keep everything in the same thread, so that there's no question about the back-story.

Anchor said:
I can't see not completing and chipping.

I can't help with computer tuning. Others here, can.

Anchor said:
Not too fond of the fact I will probably have to burn 82 octane

I'm guessing you mean 92 octane, not 82.

Anchor · Jun 10, 2024

"Thanks, Shurkey for letting me know not to start a second thread. Also, I apologize for being so needy of information. I have done a lot of reading about heads and am confused. The swirl port heads seem to be almost universally bashed but a few folks defend them for Whoever assembled this engine used the swirl ports and the stock exhaust. I am an old guy and not a racer. I have also read a lot of bad reviews of aftermarket aluminum heads and don't want to have to drill holes or alter heads. I like torque. Also, I just put an expensive exhaust system on the truck and if I go to headers I need to pretty much toss it. I also don't hate cataclysmic converters necessarily and want my computer to work properly. Bottom line, are there any out there who could see upsides to leaving swirlport heads and stock exhaust in conjunction with 383 stroker, Comp c"ams hydraulic roller 08-500-8 cam, 480in. intake and .488 exhaust .o40 over pistons, stock tbi,? We live way out of town and most of my driving is highway. 5000 rpm would be a very rare thing for me. But i might like to get to speed quickly. If headers become necessary I could change at any time but the heads I don't like doing with the engine in the truck. By the wa, I mentioned the other day that the block didn't appear to be relieved for stroker crank but I believe I was wrong. I plan on getting a new prom card or chip, or whatever it is. I have to think that with these components a lot of my running issues were caused by this.

thinger2 said:
You might have a rocker stud pulling out .
Sometimes when valve geometry keeps getting more wierd it might be the rocker stud getting loose.
Or a crack in the rocker
That can be hard to track down because it only happens during the heat/ cool cycle.
Are you running a two part or dual valve spring setup?
Is the small spring seated?
Is the large spring broken?
I think you need to take another look at that stuck exhaust valve before you do anything else.

Thinger, to your earlier question, dual valve springs- no broken outer springs- Waiting now to take in heads till I am sure I am going to use them.

PlayingWithTBI · Jun 10, 2024

Anchor said:
I have also read a lot of bad reviews of aftermarket aluminum heads and don't want to have to drill holes or alter heads. I like torque.

If you can find Aluminum heads for TBI, you'll have no problems with it but, they're few and far between anymore. You can get a spread bore intake for TBI and use an adapter plate for your Throttle Body.

Anchor said:
I just put an expensive exhaust system on the truck and if I go to headers I need to pretty much toss it

You need to decide how much money you wanna spend. A 383 with restrictive intake and exhaust is counter intuitive.

Anchor said:
are there any out there who could see upsides to leaving swirlport heads and stock exhaust in conjunction with 383 stroker, Comp c"ams hydraulic roller 08-500-8 cam, 480in. intake and .488 exhaust .o40 over pistons, stock tbi,?

Cost but, not much else

I'm not a fan of those 193 junk heads but that's my opinion. I'm lazy and don't see any sense in working on junk just to get better junk. Your running a fairly mild cam. I'm running, on my Blue Print"383", the 08-432-8 cam with the Edelbrock 3704 TBI intake, a bored 46mm TB running at 20 PSI and stock 5.7L 61PPH (flow matched) injectors up to around 5800 RPM against the rev limiter. With shorty headers, to a 3" Y pipe, high flow Cat, and straight through muffler I'm getting plenty of flow. Note, the Shorty headers bolt right up in place of the stock cast iron manifolds. And believe me, shorties DO HELP as long as the rest of your system is free flowing, not as much as LTs but do help.

Anyway, yes you s/b able to run your stock TB as is up to ~5000 RPM (well maybe 4500), not much more, just jack up the pressure a little.

Anchor said:
I plan on getting a new prom card or chip, or whatever it is. I have to think that with these components a lot of my running issues were caused by this.

That could be, have you thought about getting the EBL Flash-II? You can tune it on your own, especially with a WBO2.

EBL_Flash

It's a joy to get out, hit the skinny pedal, and romp around. My problem is, I can't give it more than 1/2 throttle without smoking the right side tire with .411:1 gears and 275/60R15s - no posi! :banghead:

Maybe sometime soon...YMMV

thinger2 · Jun 10, 2024

Anchor said:
It turns out that I really needed a tear down to find out what I had. Thank you to those of you who have responded to my post and been helpful. Should I start a new post now that I have some answers? Here is the situation as it stands. The engine does not have enough miles on it to be dirty. As I mentioned earlier over 190lbs compression in all cylinders. 383 stroker with comp cams 08-500-8 hydraulic roller cam. Scat crankshaft and rods. Stock prom card in ecm? Can't not be a problem I think. Now, since I didn't have to buy all of these parts I am thinking the swirl port heads got to go along with factory exhaust. It had an older Holley 670 tbi on when I got it and it dumped fuel so I put on a stock tbi unit. I'm not in a big hurry and need to research heads and intake as well as bigger injectors. With all of the other parts already here I can't see not completing and chipping. Boy is this project in flux. Not too fond of the fact I will probably have to burn 82 octane but it is bearable.If you guys want to chip in with ideas I am all ears. Also if you think I should make a whole new post to get more ideas let me know. I'm not dying to spend money on it but we already think the stock heads need work. I could apply that to new heads. My how these projects have a way of growing! Thank all of you

I left a voice mail with a friend who had should have some insite.
About ten or more years ago we stuck a 383 stroker in a 19 foot bayliner and had a bunch of screwy valve train problems.
I just dont remember what caused it.
I do remember it being a lot of lift for stock heads

Anchor · Jun 13, 2024

Here is what I have figured out so far. The Scat crank had been drilled and filled with Mallory, Whatever the bleep that is. I guess some kind of heavy metal for balancing. I took crank and rods into a local machinist that builds serious race cars and he said I need to have crank mains turned and rod journals polished. Didn't look that bad to me but I know when to listen. Since it has been internally balance the consensus is that the weighted balancer on front of engine takes a balanced engine and throws it out of whack. I guess I still need a weighted flex plate though. I almost threw up my hands and started looking for a crate motor but just don't want to give up. I'm going to try and do some more research on changing to a neutral balancer to smooth it out. Just very hard to find info on the combo of external and internal balancing. Any input welcome. Thank you.

Thinking teardown

Schurkey

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thinger2

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Anchor

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thinger2

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Anchor

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