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Old 01-13-2016, 08:13 AM   #101
Money_pit
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Re: Starting my engine build

Some head manufacturers are different but I've seen a few require different length push rods than oem ones. And I'd check what rear end gear you have to see kinda where your cruise speed will be its kinda gotta jive with the converter. Basically you'll end up burning the trans up. If the cruise speed isn't past the flash point of the converter. If do some digging I think b&m or I'm sure someone else also make a chart to tell what converter to use depending on rear gear and cruise speed. You may also want to get a descent additional trans cooler stalls tend to heat up more. The one piece pan gasket I was talking about is a oil pan gasket really cool gasket. Better than any cork one I've ever used
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Old 01-13-2016, 08:26 AM   #102
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Re: Starting my engine build

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Some head manufacturers are different but I've seen a few require different length push rods than oem ones. And I'd check what rear end gear you have to see kinda where your cruise speed will be its kinda gotta jive with the converter. Basically you'll end up burning the trans up. If the cruise speed isn't past the flash point of the converter. If do some digging I think b&m or I'm sure someone else also make a chart to tell what converter to use depending on rear gear and cruise speed. You may also want to get a descent additional trans cooler stalls tend to heat up more. The one piece pan gasket I was talking about is a oil pan gasket really cool gasket. Better than any cork one I've ever used
How do I check if the heads need different length pushrods? Call the manufacturer?
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Old 01-13-2016, 08:33 AM   #103
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Re: Starting my engine build

I have another question for you guys, hopefully a few will reply with insight. We know the engine has been rebuilt, and it's .040 over. So how do I know if the pistons are stock replacement or if they were changed to aftermarket during the rebuild? The reason I'm asking is because I want to figure out how much compression I'm going to have, that way I can start figuring out what size head gasket (thinner for more compression) AND, when I take the heads to get magnafluxed, I have the option of decking the heads just a little to add .5 or 1.0 compression. I'm not against buying premium gas at all since I only drive the truck when I get a hankering for some burnt rubber, so higher compression is ok with me
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Old 01-13-2016, 08:53 AM   #104
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Re: Starting my engine build

Calling manufacturer would be the easiest or they sell a cheap little tool to do it. We know the pistons are .40 over we would need to see the tops to tell if they were standard Pistons. I'm sure if you tell the machine shop what you have they would be able to tell you a rough idea. I'm gonna go out on a limb and say there ls no need for high octane stuff. That cam usually wants like 10.5 to 1 to be most efficient. If yours isn't quite there it'll just be a little more sluggish on the low end but... Still sound like fun
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Old 01-13-2016, 11:17 AM   #105
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Re: Starting my engine build

so if it does have stock pistons, what would the compression ratio be with 67cc chambers on the heads?
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Old 01-13-2016, 11:26 AM   #106
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Re: Starting my engine build

When you change the heads you change the compression ratio and that may make the engine smoke and also it puts more strain on the bearings.
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Old 01-13-2016, 11:28 AM   #107
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Re: Starting my engine build

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RHS bought out the pro topline company, then in turn was bought by Comp Cams,

The pro toplines are good flowing heads, the RHS was good flowing, the chamber shape however I had to use an 400 gasket ( not a factory replacement) ( i know your not running a 400, but i am trying to save you a disaster) so the fire ring would not hang into the chamber. Chamber was designed to flow around the valve, so just in case, lay the gasket over the head to make sure the fire ring lays on the milled surface, not overlapping into the chamber,

i had to get some expensive fel pro gaskets that cleared the chamber. it was shaped to clear and was recommended by RHS.
I called RHS and the guy I talked to said he didn't know of any special gasket needed for the heads. Are you pretty certain?
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Old 01-13-2016, 12:31 PM   #108
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Re: Starting my engine build

Got the cam out!! I may be wrong, but does it say Lunati on the cam? I can't believe I'm actually the rebuild myself, best experience ever. Here's some pics, maybe you guys can tell me what can it is, and what type of piston is in the truck as well
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Old 01-13-2016, 12:33 PM   #109
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Re: Starting my engine build

Opposite side...
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Old 01-13-2016, 12:34 PM   #110
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Re: Starting my engine build

Piston top, are these stock?
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Old 01-13-2016, 02:08 PM   #111
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Re: Starting my engine build

They look like regular run of the mill Pistons.cr is probably 9:1 at by best
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Old 01-13-2016, 02:58 PM   #112
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Re: Starting my engine build

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How do I check if the heads need different length pushrods? Call the manufacturer?
Hey, isn't that in the book? :-)

You get an adjustable pushrod (just one). You install it, ideally with a light spring, but probably OK either way. Then you adjust it so that as the rocker arm tip travels on the valve its travel is centered on the tip.

If the pushrod is too long, it'll be off or towards one edge, too short, the other way.

Then when you get it perfectly centered you measure the pushrod. Then you buy pushrods that length.

If you're lucky it's just a standard length and you're fine. Otherwise it adds a few bucks for the nonstandard length.

You'll be stuck a few days waiting on it unless a local parts store rents them, but I recall they're pretty darned cheap if you can find them.
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Old 01-13-2016, 03:01 PM   #113
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Re: Starting my engine build

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so if it does have stock pistons, what would the compression ratio be with 67cc chambers on the heads?
You'd need a depth gauge (depth micrometer or similar) to know how far down in the hole the piston is; generally that's actually a measurement of how tall the deck is, if you think about it, because the rods and pistons should be standard.

But you need to know that as well as the compressed thickness of the gasket AND the cc size of the reliefs in those pistons.

You can probably get close talking to a head company and telling them it's a 350 with flat top pistons with 4 little valve reliefs and that the engine has been rebuilt before. You'll probably assume it's been cut to a flat deck (piston top flat with the deck). Then if the deck is actually any higher you get slightly lower compression than you thought. Better than too much.

If you have aluminum heads and are shooting for 10:1 or something (no idea) and wind up 9.8:1 you'll never know and the horsepower difference is close to 0.
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Old 01-13-2016, 04:52 PM   #114
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Re: Starting my engine build

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They look like regular run of the mill Pistons.cr is probably 9:1 at by best
How sure are you on that 9-1 compression? I'm reading that the cam I got likes 10.5-1 so I'll just try to get close with a thin gasket.

Looks like camaros had 10.25-1 in 1970, and other small blocks had 9.0-1 or 10.0-1

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Old 01-13-2016, 04:53 PM   #115
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Re: Starting my engine build

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Hey, isn't that in the book? :-)

You get an adjustable pushrod (just one). You install it, ideally with a light spring, but probably OK either way. Then you adjust it so that as the rocker arm tip travels on the valve its travel is centered on the tip.

If the pushrod is too long, it'll be off or towards one edge, too short, the other way.

Then when you get it perfectly centered you measure the pushrod. Then you buy pushrods that length.

If you're lucky it's just a standard length and you're fine. Otherwise it adds a few bucks for the nonstandard length.

You'll be stuck a few days waiting on it unless a local parts store rents them, but I recall they're pretty darned cheap if you can find them.
Book is on the way I just couldn't wait haha
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Old 01-13-2016, 04:56 PM   #116
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Re: Starting my engine build

That cam you pulled out is a Lunati 285 Bracketmaster 2. Decent cam for street performance. Has a fairly lopey idle and decent mid to top end range. Would need around a 2200 RPM stall and lower gears in the rearend. Believe it or not it is almost identical to the cam you just bought.

The Bracketmasters are kind of old school like the Comp Magnum series and can produce decent power. There are better cams out there. The XE line of cams from Comp Cams are a good line up as well as the Lunati Voodoo series.

Gary
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Old 01-13-2016, 05:06 PM   #117
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Try to keep it 9.5 to 1 or lower if you want to run pump gas. With a street engine, pushing the compression envelope for a small gain in power is not worth it. Trust me. It sucks hearing your engine knock and ping on a road trip because you had to settle for lower octane.

Dave nailed it on the push rod procedure. With the new heads possibly changing specs, it is imperative you verify contact pattern on the valve tip. If not you risk excessive valve guide wear at the least. And dropped valves in very extreme cases. These are the things you deal with using aftermarket parts. Here is an excellent article worth reading:
http://www.hotrod.com/how-to/engine/...ushrod-length/
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Old 01-13-2016, 06:45 PM   #118
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Re: Starting my engine build

I remember reading that article when it came out. After I read it, I added a pushrod length checker to my engine building arsenal.

Gary
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Quote:
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I love using vacuum gauges as part of the carb tuning process. I hook the gauge to the inside of my garbage can and leave it there.
Quote:
Originally Posted by Marv D View Post
Remember Murphys 2nd law of mechanical relationships... "OPPOSING COMPONENTS ATTEMPTING TO OCCUPY THE SAME SPACE, AT THE SAME TIME, GENERALLY END UP OCCUPYING ADJOINING SPACE AT THE BOTTOM OF THE OIL PAN"
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Old 01-13-2016, 06:49 PM   #119
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Re: Starting my engine build

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That cam you pulled out is a Lunati 285 Bracketmaster 2. Decent cam for street performance. Has a fairly lopey idle and decent mid to top end range. Would need around a 2200 RPM stall and lower gears in the rearend. Believe it or not it is almost identical to the cam you just bought.

The Bracketmasters are kind of old school like the Comp Magnum series and can produce decent power. There are better cams out there. The XE line of cams from Comp Cams are a good line up as well as the Lunati Voodoo series.

Gary
I just looked up the specs on the Lunati I pulled, and it looks like it's bigger all the way around. More lift, more duration, so is the comp cam going to be less aggressive? I may just stick with the Lunati of its bigger. That explains why the truck lunges at stop lights
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Old 01-13-2016, 09:06 PM   #120
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Re: Starting my engine build

depends if you liked the sound / performance of the lanuti. the comp won't have as rough of idle. If it isn't an everyday driver i'd look into a comp 292h so you get a real snotty idle
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Old 01-13-2016, 10:18 PM   #121
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Re: Starting my engine build

The lunati has similar duration but less lift than your comp cams selection. Lunati .455 and comp at .480.
The real difference will be in the idle.
The lunati will be way less lumpy. It has 114 degrees lsa compared to the comp lsa of 110.
The tighter the lsa the more radical the idle. Thumper cams usually have even tighter lsa's. At 106 degrees.
Wider lsa's are more easily tuned for street driving. Broader hp and torque.
At least with the comp cam you'll really learn how to tune.
I noticed you're into the 'snowball effect' on your build!
Snowball starts small at the top of the hill and becomes bigger the farther down the hill it rolls!
Same with most builds. Start off thinking a couple upgrades and before you know it you coulda had a motor built by a pro.
I'm guilty of that!
Built a knarly 454 for double the money I would have spent on a simple 6-71 blower build.
At least you're getting lots of different ideas from everyone.
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Old 01-13-2016, 11:06 PM   #122
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Re: Starting my engine build

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The lunati has similar duration but less lift than your comp cams selection. Lunati .455 and comp at .480.
The real difference will be in the idle.
The lunati will be way less lumpy. It has 114 degrees lsa compared to the comp lsa of 110.
The tighter the lsa the more radical the idle. Thumper cams usually have even tighter lsa's. At 106 degrees.
Wider lsa's are more easily tuned for street driving. Broader hp and torque.
At least with the comp cam you'll really learn how to tune.
I noticed you're into the 'snowball effect' on your build!
Snowball starts small at the top of the hill and becomes bigger the farther down the hill it rolls!
Same with most builds. Start off thinking a couple upgrades and before you know it you coulda had a motor built by a pro.
I'm guilty of that!
Built a knarly 454 for double the money I would have spent on a simple 6-71 blower build.
At least you're getting lots of different ideas from everyone.
I was just thinking that today haha it's getting more expensive by the day. But, it's really fun and I'm learning a lot. I never would've thought I'd be doing heads and cam without shelling out money for shop labor. It's only gonna get more expensive too because next I'm doin a stall converter, then posi with 3.73' or something similar, then I'm gonna want disk brakes.....the list goes on I really appreciate all the help I get from you guys, this site is awesome.

I think I'm gonna go ahead with the comp 280H. I'd go bigger, maybe a 292H, but it doesn't come on til 2500rpm and that's a little late even for me haha I haven't bought gaskets yet, but so far it's been under 1000 bucks and that's including brand new performance heads, cam and lifters, valve springs, Edelbrock 650 avs, deep trans pan, Edelbrock double roller timing set, Performer RPM intake, and some nice tools too. I figure it's goin ok so far. Next time though, I'm going to buy an engine stand and cherry picker, and start with a brand new 383 short block and go from there. That's gonna be a fun build
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Old 01-13-2016, 11:07 PM   #123
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Re: Starting my engine build

Here's a question, do people sell used camshafts? As long as they are in good shape? I definetly won't be using the Lunati cam, but it's a shame to see it just sit around
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Old 01-13-2016, 11:43 PM   #124
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Re: Starting my engine build

Well I didn't get much done today, just pulled the old cam and then took the new heads to be magna fluxed and cleaned. I did learn a lot though. Thanks for the continued replies I appreciate all the help
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Old 01-14-2016, 02:39 PM   #125
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Re: Starting my engine build

Back to it today. Waiting on heads to be done and rocker arms to come in the mail, so it's time to start the scraping of old gaskets and silicone
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