Here We Go: My 383 Stroker Winter Project

[greg82255]

Re: Here We Go: My 383 Stroker Winter Project

In one of the DVDs I watched, it said that if you don't plan to start your engine for a few weeks, then you should use a white lithium grease on the balancer. I think I'll go with white lithium grease on both the balancer and the rear main seal.

I got the heads, intake and exhaust manifolds painted yesterday, and they were finished drying this morning. Here are some pics:

Everything Drying:

Finished Vortec Heads:

Exhaust Manifolds: There's an annoying little run next to what I think is a welch plug, but I'll sand that up and re-shoot it at some point.

RPM Air Gap Intake: I know everyone says don't paint these b/c they look good already, but I couldn't resist. I love that Mercury Racing metallic blue

 

[Tail_Gunner]

Re: Here We Go: My 383 Stroker Winter Project

Well there is a old saying "Any Grease is Better than No Grease At All"......wipe on wipe off.

 

[John_S]

Re: Here We Go: My 383 Stroker Winter Project

Test fit your carb to intake. Part of the top of the intake may still be exposed. May want to paint now, vs touch-up latter.


I had to do touch-up on my vortec performer / 1409 combo.

 

[greg82255]

Re: Here We Go: My 383 Stroker Winter Project

Test fit your carb to intake. Part of the top of the intake may still be exposed. May want to paint now, vs touch-up latter.


I had to do touch-up on my vortec performer / 1409 combo.

I didn't think to do that - I'll check it tomorrow morning. thanks John.

Finally out of school for the winter so i can make some real progress now.

 

[RogersJetboat454]

Re: Here We Go: My 383 Stroker Winter Project

Looks good Greg.
Nothing wrong with painting the intake. Yes the bare aluminum does look nice when it comes out of the box, but in a year it would be covered in white rust. Plus that blue is a sweet looking color!

 

[greg82255]

Re: Here We Go: My 383 Stroker Winter Project

Looks good Greg.
Nothing wrong with painting the intake. Yes the bare aluminum does look nice when it comes out of the box, but in a year it would be covered in white rust. Plus that blue is a sweet looking color!

Thanks, I really like the blue too. I got the short block finished up and put the heads on today. I'm uploading some pictures now.

 

[greg82255]

Re: Here We Go: My 383 Stroker Winter Project

Alright, the short block is done. Long block is almost done. I worked for a few hours today and everything went fairly smooth. The oil pump, timing cover, and the oil pan went on without much trouble. The rear main seal was the most annoying part of the build so far. It took me 30 minutes to get that thing on the crank without the spring falling off or the seal folding over. Here is a picture of the long block:

 

[greg82255]

Re: Here We Go: My 383 Stroker Winter Project

On to my next question. I think I need some help measuring the correct push rod length. I've read a few manuals and watched a few videos on it, and there are a few different sets of instructions. I know that you mark the valve tip with a dry erase marker and turn the engine over a few times and want the mark in the center of the valve, but my question is how to adjust the rocker arm before you turn the engine over. Some manuals say to adjust to zero lash and some say to adjust to zero lash plus 1/2 turn. Which is correct, or does it not make much of a difference? I adjusted to zero lash plus 1/2 turn and got 7.100 as my rod length (6.800 adjustable push rod turned out 6 times, 6*.050+6.800 = 7.100 inches).

Here's some pictures of how I did it:

The lifter and rod in the block:

Here's the mark it left. It's right in the center:

 

[joewithaboat]

Re: Here We Go: My 383 Stroker Winter Project

Coming along great, love the blue paint.
I cant tell from the picture but I'm guessing that those are self aligning rockers?

I'm not familiar with the 906 vortec casting specifically but was curious if they are prone to having the rocker studs pull out like all older Chevy heads did. Generally heavy spring pressure is what will cause this but so will constant high rpm operation like I'm sure this engine will encounter. I bet John S will have some advise here on that subject.

As for the pushrods... i think retro roller kits come with 7.300, If I'm remembering correctly factory rollers are 7.200. Are you using a reduced base circle cam for clearance purpose's.

So you are rotating the engine over to check the valve tip pattern.... How are you keeping the hydraulic lifter from collapsing with no oil in it. I think you need a light weight test spring on that valve that wont collapse the lifter just for measuring purposes.

The witness mark looks good in the picture ! Nicely centered.

 

[John_S]

Re: Here We Go: My 383 Stroker Winter Project

I don't know if there are any set rules, spring pressure, rocker ratio, rpms, etc, that dictates when you should use screw in studs or pinning, but it is common for reworked performance heads to have it done, vortecs included. It is probably a good insurance policy. In more radical builds, seen the self-aligners replaced with non, and guide plates added.

For that matter, don't know what springs were used or how machinist decided to get the lift needed for cam, etc. While I'd want to know more details , at this point, trust the machinist. Don't think having them redone by a different one at this point, is worth it

Greg, what valve covers did you go with? Stock center-bolts, might need trimming of inner cross ribs with those rockers. Do a test fit with all rockers installed. Also, if a tall aftermarket cover, check fit with the exhaust manifold installed. You may find you can't remove/install cover without loosening up the exhaust manifold.

 

[joewithaboat]

Re: Here We Go: My 383 Stroker Winter Project

I worked in a performance engine machine shop for 2 years while in college. It was pre vortec (around 94,95) so i don't want to claim i know about machining vortec heads because i haven't. Unless GM was doing something different when producing these castings, not likely, You may have problems. A quick look around the net tells me folks are converting these to screw in studs just like all previous castings.

If you already have self aligning rockers you can skip the guide plates. I would for sure look into this. You can even buy kits that have guide blocks so you can do it yourself if you want. As to trusting your machinist.... he sold you the wrong cam, insisted you buy his intake which by all industry knowledge was not the one best suited for your application. I don't know wither i would be going by his opinion alone.
This isn't the end of the world and its not like your engine will blow up because of it. Sometimes they just pull up a little and your valve train starts clattering, sometimes they come out all at once. Worse case you could break something.

 

[joewithaboat]

Re: Here We Go: My 383 Stroker Winter Project

Also if your machinist was a 383 guru he would have been able to tell you from your combination of parts and deck height etc. about what your push-rod length should be. That doesn't mean he is not an excellent machinist just that maybe he is not the go to guy for the best decisions on this build.

 

[greg82255]

Re: Here We Go: My 383 Stroker Winter Project

Coming along great, love the blue paint.
I cant tell from the picture but I'm guessing that those are self aligning rockers?
As for the pushrods... i think retro roller kits come with 7.300, If I'm remembering correctly factory rollers are 7.200. Are you using a reduced base circle cam for clearance purpose's.

So you are rotating the engine over to check the valve tip pattern.... How are you keeping the hydraulic lifter from collapsing with no oil in it. I think you need a light weight test spring on that valve that wont collapse the lifter just for measuring purposes.

They are self-aligning rockers. I just put light oil on the lifters before I put them in the block. Does this mean I need to remove the spring from the valve and put a lighter weight spring?

I don't know if there are any set rules, spring pressure, rocker ratio, rpms, etc, that dictates when you should use screw in studs or pinning, but it is common for reworked performance heads to have it done, vortecs included. It is probably a good insurance policy. In more radical builds, seen the self-aligners replaced with non, and guide plates added.

For that matter, don't know what springs were used or how machinist decided to get the lift needed for cam, etc. While I'd want to know more details , at this point, trust the machinist. Don't think having them redone by a different one at this point, is worth it

Greg, what valve covers did you go with? Stock center-bolts, might need trimming of inner cross ribs with those rockers. Do a test fit with all rockers installed. Also, if a tall aftermarket cover, check fit with the exhaust manifold installed. You may find you can't remove/install cover without loosening up the exhaust manifold.

I'm not sure what springs are in there. I was told that I needed to put in upgraded springs to accommodate the bigger cam, so I just went with it. As for the valve covers, I went with stock center-blots - they aren't very tall. I'll definitely do a test fit once I get the rockers in there.

I worked in a performance engine machine shop for 2 years while in college. It was pre vortec (around 94,95) so i don't want to claim i know about machining vortec heads because i haven't. Unless GM was doing something different when producing these castings, not likely, You may have problems. A quick look around the net tells me folks are converting these to screw in studs just like all previous castings.

If you already have self aligning rockers you can skip the guide plates. I would for sure look into this. You can even buy kits that have guide blocks so you can do it yourself if you want. As to trusting your machinist.... he sold you the wrong cam, insisted you buy his intake which by all industry knowledge was not the one best suited for your application. I don't know wither i would be going by his opinion alone.
This isn't the end of the world and its not like your engine will blow up because of it. Sometimes they just pull up a little and your valve train starts clattering, sometimes they come out all at once. Worse case you could break something.

I'll ask the machinist about converting to screw-in rocker studs. I assume it's not that difficult - just pulling the old ones out and tapping the holes? He is definitely a great machinist but Joe I agree he may not be the best guy for my specific application. He never works on blocks that aren't OEM roller, and he mostly does LT1, LS1, LS3, and LS7 racing motors. Before he switched the cam he tried to make it fit in the block with a cam button and wear plate but it didn't work so I eventually said lets just buy the retrofit roller. He also said to not bother with the melonized distributor gear or brass tip fuel pump rod, but I'll be buying those anyway.

 

[John_S]

Re: Here We Go: My 383 Stroker Winter Project

He should have matched the springs to your cam and lift w/1.6 rockers. Vortec stock springs are 80lbs, which most consider barely capable of stock cams. If I had to guess, 120lb springs is probably what he used. What was the max lift that he indicated? I assume he OKed the change from 1.5 to 1.6 rockers. Stock vortecs are limited by the retainer to valve guide oil seal, with a max lift of about 0.470". There are a number of ways he could get vortecs to handle the lift. Prefered way is machining the heads. Grinding the valve retainer is commonly called the "ghetto grind". Beehive springs are another, but from the pics, didn't use that. Anyway, you should have record of what machine work and parts that were used. Valves, valve seals, springs, retainers, etc. I might have mentioned some of this in the early thread, when you were asking about possible heads to run. I'd get all the info, and then discuss your application with another head shop (2nd opinion). Given what the parts are and a rev limit of 5200, they may not recommend screw-ins. I'll take a closer look a the Merc Black Scorpion specs/pics to see if I can tell what was done there. Do the homework before wasting a set of head gaskets.

PS: Also, going to 1.6 rockers on vortecs can cause pushrod clearance issues where it goes through the round hole (not slotted) in the head. Check to see if he machined these holes larger. I have seen builds where this was required and others where it wasn't. I beleive the Hot Rod article on the HT383 build had clearance issues.

Note: The Hot Rod article DIDN'T mention the issue, it was Chevy Hi-Performance: http://www.chevyhiperformance.com/techarticles/76178_chevrolet_ht_383_engine/photo_06.html

Note2: Checked the Black Scorpion Service Manual, and the rocker arm stud removal procedure indicates just pressed in studs. CORECTION: The Black Scorpion uses screw in studs.

 

[greg82255]

Re: Here We Go: My 383 Stroker Winter Project

He should have matched the springs to your cam and lift w/1.6 rockers. Vortec stock springs are 80lbs, which most consider barely capable of stock cams. If I had to guess, 120lb springs is probably what he used. What was the max lift that he indicated? I assume he OKed the change from 1.5 to 1.6 rockers. Stock vortecs are limited by the retainer to valve guide oil seal, with a max lift of about 0.470". There are a number of ways he could get vortecs to handle the lift. Prefered way is machining the heads. Grinding the valve retainer is commonly called the "ghetto grind". Beehive springs are another, but from the pics, didn't use that. Anyway, you should have record of what machine work and parts that were used. Valves, valve seals, springs, retainers, etc. I might have mentioned some of this in the early thread, when you were asking about possible heads to run. I'd get all the info, and then discuss your application with another head shop (2nd opinion). Given what the parts are and a rev limit of 5200, they may not recommend screw-ins. I'll take a closer look a the Merc Black Scorpion specs/pics to see if I can tell what was done there. Do the homework before wasting a set of head gaskets.

PS: Also, going to 1.6 rockers on vortecs can cause pushrod clearance issues where it goes through the round hole (not slotted) in the head. Check to see if he machined these holes larger. I have seen builds where this was required and others where it wasn't. I beleive the Hot Rod article on the HT383 build had clearance issues.

Note: The Hot Rod article DIDN'T mention the issue, it was Chevy Hi-Performance: http://www.chevyhiperformance.com/techarticles/76178_chevrolet_ht_383_engine/photo_06.html

Note2: Checked the Black Scorpion Service Manual, and the rocker arm stud removal procedure indicates just pressed in studs.

He picked the cam, and he did OK the 1.6 rockers and said they would work with the heads with no problems. The cam lift is .495/.503, and if my math is right the 1.6 rockers would increase lift to .528/.536. He bought the springs after he picked the cam and knew about 1.6 rockers so I assume he bought springs that would work with both. He didn't tell me the max lift that the springs would work with, but I'll get it from the part # on the invoice. I'm not sure what machining was done to the heads besides resurfacing them, but I'll check my invoice. The invoice definitely doesn't include what seals were used, but it does have the exhaust valves (he was able to reuse the stainless intake valves), and he reused the retainers that were on there - he said they were comp cams hardened retainers so I didn't need new ones.

I'll have to ask my machinist what he did to the heads to make them compatible with the higher lift. I'll also ask if he did anything about the pushrod clearance issues. Can I just check the clearance myself? If he thought I needed screw-in studs he probably would have said so, but I think you're right that I may want to get another opinion.

 

[John_S]

Re: Here We Go: My 383 Stroker Winter Project

Your lift is just slightly more than the Black Scorpion (.510/.530).

I don't know how much gap should be around the pushrod. from the looks of the pic on HiPerf Chevy, I'd say it was just brushing against it at high rpms. Another good question to ask the machinist.

 

[joewithaboat]

Re: Here We Go: My 383 Stroker Winter Project

Looks like mercruiser provides two different over size studs to replace ones that might get loose on the Black scorpion. This is one of three locations i found the same thing. Looks like they don't use screw in studs but provide for over size ones that might pull.

http://www.perfprotech.com/store/assembly/CYLINDER-HEAD-AND-ROCKER-COVER,2349-15.aspx

Here is a link with pictures of that tool that you could thread them yourself. The guy i think is using the wrong studs, he should be using shorter ones with no base. He later figures that out. But it will give you an idea of what you are up against.

http://forums.corvetteforum.com/c3-...nstalling-screw-in-studs-in-vortec-heads.html

 

[joewithaboat]

Re: Here We Go: My 383 Stroker Winter Project

Not sure if you have looked at comps specs and recommendations for this cam but they are calling for nearly 350lbs of open spring pressure. Id be looking to install screw in studs for sure.

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=169&sb=2

I am blown away that he told you not to worry about changing the distributor gear. You need a bronze or check out comps new composite.

 

[greg82255]

Re: Here We Go: My 383 Stroker Winter Project

Here is a link with pictures of that tool that you could thread them yourself. The guy i think is using the wrong studs, he should be using shorter ones with no base. He later figures that out. But it will give you an idea of what you are up against.


http://forums.corvetteforum.com/c3-...nstalling-screw-in-studs-in-vortec-heads.html

If I were to drill and tap the rocker studs myself, could this be done with the heads still on the block, or would I have to take them off? I suppose if it's really necessary then it doesn't matter, but I'd just like to know if I need to order some new head gaskets. I figure they should probably come off to avoid any metal shavings falling into the block/lower end. I also have rockers for 3/8" studs, but I'm assuming I would have to drill/tap for 7/16" screw-in studs, so I would need to exchange my rockers too. How necessary is it to have the screw-in studs?

I am blown away that he told you not to worry about changing the distributor gear. You need a bronze or check out comps new composite.

My trust in him has been shaken a little since he tried to make the OEM roller cam work in my block even though they are clearly 2 different parts. He doesn't do much with marine applications or really anything besides high performance racing products, so I think his knowledge of the minor details outside of his area or expertise may be limited. I'm going to order the melonized distributor gear and bronze tip fuel pump rod. I'll check out the Comp Cams composite gear too.

 

[boatnut74]

Re: Here We Go: My 383 Stroker Winter Project

If I were to drill and tap the rocker studs myself, could this be done with the heads still on the block, or would I have to take them off?

It really depends what type of studs you are putting in. If you are going to install the ones with the hex at the base the pedastals will need to be machined down. If you are just going to use the factory style that are threaded you could do it with the heads on but it's not recommended. Like you said you run the risk of getting metals shavings in your brand new engine. Not worth the risk IMO.