nx284h lets talk cam and springs - Page 4 - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Hotrodding Basics
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #46 (permalink)  
Old 03-10-2014, 10:53 AM
Registered User
 
Last photo:
Join Date: Jan 2013
Posts: 168
Wiki Edits: 0

Thanks: 10
Thanked 35 Times in 32 Posts
Built a 1966 L-35 396. All stock components with some high rise aluminum manifold (can't remember which one) just port matched and a comp cams 268h with a 800Q-jet. Set of Thorley headers and glasspacks out the back, HEI distributor, M20 4spd with 12 bolt 3.73's. Great street engine. No lopey rump-rump, just rumbled! Wife's car back then, 66 Impala SS.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #47 (permalink)  
Old 03-10-2014, 10:56 AM
Registered User
 
Last photo:
Join Date: Jan 2013
Posts: 168
Wiki Edits: 0

Thanks: 10
Thanked 35 Times in 32 Posts
Quote:
Originally Posted by ss454lemy View Post
do you think id run in to clearance issues with the nx284h cam? with the 049 heads they 119 cc combustion chamber. the guy is giving me a hard time returning the cam and it was my mistake placing that order. hes a good friend of mine and i don't really want to bug much....
I would most definitely clay check that cam for valve to piston clearance in it's full rotation!
Reply With Quote Quick reply to this message
  #48 (permalink)  
Old 03-10-2014, 11:01 AM
ss454lemy's Avatar
Registered User
 
Last photo:
Join Date: Feb 2014
Posts: 130
Wiki Edits: 0

Thanks: 57
Thanked 1 Time in 1 Post
Quote:
Originally Posted by 66GMC View Post
It sounds like you're getting some great advice on this thread, and I can tell you that it's a "deja-vu" moment ... almost identical to my 454 build dreams and real-life experience.

Yup, I wanted the 8-71 blower sticking outta my hood too, (still sorta do. ) as an "upgrade path".

I started out with a good core, then had it built with .030 Forged Flat-tops, 781 (118+ cc) heads, Air Gap intake, Holley #3310 750CFM VS carb, Hedman truck headers, TH400, B&M Nitrous Holeshot 2400 stall convertor, 3.73:1 truck diff.

Cam #1, original to the fresh rebuild, had similar specs to a "blower cam" with a 224 duration on 114 centerline (IIRC) and it was LAZY picking up RPM.
We had break-in issues, and it wiped a lobe ... which probably contributed to the "lazy" as well. I thought it idled much too smoothly anyway.

So, faced with replacing the cam, I went overboard and installed cam#2, an XE284H, looking for a rougher idle ... which I got. It turned out to be pretty much "un-tunable" in fact. That's when I learned about DCR.

So OK, the intake was puking oil out the china wall, so I decided (with advice received here) to peel it off, replace the gaskets, and just use silicone on the rear china wall. When the intake came off, I found that I had other problems ... some NASTY Technicolor goo in the LH rear cooling port on the cylinder head. I suspected it was caustic soda, so I cleaned it up, re-assembled the engine, flushed the block and rad, adjusted the rockers, and fired it up.

The good news? No more oil leak.
The bad news? I must have made an error when adjusting the rockers, and wiped another cam lobe.

OK ... enough! I went out and bought ANOTHER flat-tappet cam (XE268H) as well as a set of closed-chambered (110cc) 396 heads, trying to get that compression up.

Having discussed flat-tappet cams at great length, I cannot bring myself to put it all back together again.

At this point in time, I have the short-block sitting in the frame under a blanket, A new cam and lifters in their un-opened boxes, 2 sets of heads on the bench ... and a strong desire to spend my cash on vacations rather than on this boat-anchor 454!

OK, seriously, I do plan to buy a ROLLER cam with a similar (performance street) profile XR282HR and put it together with the higher-compression heads. The blower thing may never happen, But I'll keep those 781 heads in case it does.

Hopefully you (and maybe others) can learn from my misfortune, and not make the same mistakes.
i really hope i have better luck than that with this cam. if not ill have to bite the bullet and go roller witch i don't have the cash for right now.
Reply With Quote Quick reply to this message
  #49 (permalink)  
Old 03-10-2014, 11:09 AM
Registered User
 
Last photo:
Join Date: Jan 2013
Posts: 168
Wiki Edits: 0

Thanks: 10
Thanked 35 Times in 32 Posts
Roller cams are the only way to go these days! Engine oil contents have changed and running a flat tappet is not your best option. It still can be done, you just have to be very careful on oil choice with ZDDP additives and break-in HAS to be done correctly! Every oil change HAS to have a ZDDP additive if you want a chance for the cam to survive.
Reply With Quote Quick reply to this message
  #50 (permalink)  
Old 03-10-2014, 11:20 AM
ss454lemy's Avatar
Registered User
 
Last photo:
Join Date: Feb 2014
Posts: 130
Wiki Edits: 0

Thanks: 57
Thanked 1 Time in 1 Post
Quote:
Originally Posted by steeny View Post
Roller cams are the only way to go these days! Engine oil contents have changed and running a flat tappet is not your best option. It still can be done, you just have to be very careful on oil choice with ZDDP additives and break-in HAS to be done correctly! Every oil change HAS to have a ZDDP additive if you want a chance for the cam to survive.
ok so i have to buy the oil that comes with ZDDP or i have to buy ZDDP to add to my oil?
Reply With Quote Quick reply to this message
  #51 (permalink)  
Old 03-10-2014, 11:23 AM
Registered User
 
Last photo:
Join Date: Jan 2013
Posts: 168
Wiki Edits: 0

Thanks: 10
Thanked 35 Times in 32 Posts
Either way. But I think it is cheaper to just by the additive.
Reply With Quote Quick reply to this message
  #52 (permalink)  
Old 03-10-2014, 11:28 AM
Registered User
 
Last photo:
Join Date: Jan 2013
Posts: 168
Wiki Edits: 0

Thanks: 10
Thanked 35 Times in 32 Posts
Gotta get something accomplished today guy's..............later.
Reply With Quote Quick reply to this message
The Following User Says Thank You to steeny For This Useful Post:
ss454lemy (03-10-2014)
  #53 (permalink)  
Old 03-10-2014, 11:39 AM
ss454lemy's Avatar
Registered User
 
Last photo:
Join Date: Feb 2014
Posts: 130
Wiki Edits: 0

Thanks: 57
Thanked 1 Time in 1 Post
Quote:
Originally Posted by steeny View Post
Gotta get something accomplished today guy's..............later.
thanks man i greatly appreciate your help!!!! am over here with a fever at work shoot me !!!
Reply With Quote Quick reply to this message
  #54 (permalink)  
Old 03-11-2014, 06:20 AM
ss454lemy's Avatar
Registered User
 
Last photo:
Join Date: Feb 2014
Posts: 130
Wiki Edits: 0

Thanks: 57
Thanked 1 Time in 1 Post
u guys think it will be worst of a dog than it was stock ?
Reply With Quote Quick reply to this message
  #55 (permalink)  
Old 03-11-2014, 06:37 AM
vinniekq2's Avatar
Registered User
 
Join Date: Jun 2012
Location: BC,Canada
Age: 56
Posts: 7,405
Wiki Edits: 0

Thanks: 291
Thanked 707 Times in 682 Posts
roller/flat

Quote:
Originally Posted by ss454lemy View Post
i really hope i have better luck than that with this cam. if not ill have to bite the bullet and go roller witch i don't have the cash for right now.
If the cam fails,you should take the engine completely out and freshen,,,that metal has to go somewhere? like through the bearings or?
Read techinspector1 's tutorial on flat tappet cams,,,,
Reply With Quote Quick reply to this message
  #56 (permalink)  
Old 03-11-2014, 08:58 AM
66GMC's Avatar
Get in, sit down, hang on
 

Last journal entry: Cab Removal
Last photo:
Join Date: May 2005
Location: Olds, Alberta Canada
Age: 56
Posts: 2,761
Wiki Edits: 0

Thanks: 32
Thanked 90 Times in 85 Posts
Quote:
Originally Posted by vinniekq2 View Post
If the cam fails,you should take the engine completely out and freshen,,,that metal has to go somewhere? like through the bearings or?
Read techinspector1 's tutorial on flat tappet cams,,,,
I'm assuming you were talking about my situation?


The machinists instructions following the failure of cam #1 was to:
1.) spray varsol with an air-pressurized cleaning gun from the intake valley downward
2.) remove the oil galley plugs and spray horizontally through the galley
3.) Drain and remove the oil pan
4.) Spray varsol upwards from the bottom, trying to catch any debris that may have been blasted around from step 1
5.) Repeat 1-3 with a mix of engine oil and varsol
6.) Drain the pan again, and clean thoroughly.
7.) Remove the rear main cap and inspect the bearing

Thankfully there are no signs of ingesting any iron powder.

This time, however, the block will be headed back to him to check lifter bore clearance as well as a thorough inspection and cleaning.

I've also nicked at least one of the cam bearings, and will have him install a new set as well.

In fact, I'll probably have him install the roller cam and assemble the engine to long-block stage.

Dang, I hate "do-overs". (Although I DO take responsibility for my own incompetence. Hey, I'm a partsman ... not a mechanic or machinist!)
Reply With Quote Quick reply to this message
  #57 (permalink)  
Old 03-11-2014, 02:46 PM
ss454lemy's Avatar
Registered User
 
Last photo:
Join Date: Feb 2014
Posts: 130
Wiki Edits: 0

Thanks: 57
Thanked 1 Time in 1 Post
i might just scratch the big block and go ls based 360 ci them ls's are sick
Reply With Quote Quick reply to this message
  #58 (permalink)  
Old 03-11-2014, 07:05 PM
vinniekq2's Avatar
Registered User
 
Join Date: Jun 2012
Location: BC,Canada
Age: 56
Posts: 7,405
Wiki Edits: 0

Thanks: 291
Thanked 707 Times in 682 Posts
66gmc
I was just saying what needs to be done if ss454lemy has a similar flat cam problem.
and ss454
The 360 LS engine is not going to make the power of a 454 well built
Reply With Quote Quick reply to this message
  #59 (permalink)  
Old 03-12-2014, 06:25 AM
ss454lemy's Avatar
Registered User
 
Last photo:
Join Date: Feb 2014
Posts: 130
Wiki Edits: 0

Thanks: 57
Thanked 1 Time in 1 Post
ohhhh yes it will!!! may be not the torque. but power yes my 360 ci put down 440 on nitrous tune. stock house ported heads and a cam. this one i leave the heads alone and put a turbo cam and boost the crap out of it and i can easily make 650 daily drive no headaches and economical!!! well see ... im trying to swap for a magnum 280h if it goes threw ill rock the 454 for a lil while.
Reply With Quote Quick reply to this message
  #60 (permalink)  
Old 03-12-2014, 06:41 AM
vinniekq2's Avatar
Registered User
 
Join Date: Jun 2012
Location: BC,Canada
Age: 56
Posts: 7,405
Wiki Edits: 0

Thanks: 291
Thanked 707 Times in 682 Posts
not going to argue

Quote:
Originally Posted by ss454lemy View Post
ohhhh yes it will!!! may be not the torque. but power yes my 360 ci put down 440 on nitrous tune. stock house ported heads and a cam. this one i leave the heads alone and put a turbo cam and boost the crap out of it and i can easily make 650 daily drive no headaches and economical!!! well see ... im trying to swap for a magnum 280h if it goes threw ill rock the 454 for a lil while.
a 454 has a much bigger bore so therefore more head flow potential which equals more horse power.
The extra 100 cubes makes a huge difference too.
you are trying to build a 454 on a shoe string and you are comparing to a more modern combination out of the box.Put a decent set of heads on the 454 and make the same or a little more horse power per cubic inch
Reply With Quote Quick reply to this message
The Following User Says Thank You to vinniekq2 For This Useful Post:
ss454lemy (03-12-2014)

Recent Hotrodding Basics posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
lets talk newbie2011 Introduce Yourself 1 12-06-2010 05:38 PM
Lets talk murray fancy Introduce Yourself 3 12-03-2010 05:32 PM
Lets talk about Patriot BMM Hotrodders' Lounge 4 09-06-2008 03:23 PM
More issues....lets talk cam failure TurboS10 Engine 23 09-28-2004 11:51 AM
Lets talk about polishing. 4 Jaw Chuck Body - Exterior 4 12-17-2002 12:53 PM


All times are GMT -6. The time now is 09:46 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.