Compression for nitrous - 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> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 10-30-2008, 06:18 PM
Registered User
 
Last photo:
Join Date: Jun 2008
Location: Mt.Vernon,IN
Posts: 484
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Compression for nitrous

I am trying to figure out what the standard CR is Ideally For a motor that will be with out NOS the majority of the time but can still handle it. I want to built one of my 400's for a good street/strip car. I'm looking for 500 HP no bottle, but have the option to run 125-200 shot if i choose to....

How much NOS can a stock 400 crank handle???? Hyper/ coated pistons/ forged rods?????

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 10-31-2008, 12:21 AM
Registered User
 
Last photo:
Join Date: Mar 2008
Location: Ringgold, Ga.
Posts: 460
Wiki Edits: 0

Thanks: 1
Thanked 17 Times in 16 Posts
It really isn't a question of how much nitrous can your crank handle , but how much total HP combined. If you are going to add 200 extra horses to your 500 horse engine, then you need to prep it in all areas like you are buiding a 700 HP engine! The last thing you want to do is run over your crank in high gear when it exits out the bottom of your oil pan. Will a 2 bolt main block be satisfactory....maybe. Will adding splayed 4 bolt caps help....Do you need main studs.....probably. Would It be better to get a Bowtie block , or Dart block to start with....400's are very good engines, and you just need to follow sensible steps to ensure you get the most pleasure and satisfaction for your intended purpose. When the NMCA craze first started, I built many big cubic inch nitrous Small Block Fords and Chevies, some had compression as high as 13-1/2 to 1 and used 400 HP Fogger kits. There are as many ways build a nitrous motor the wrong way, as there are the right way. Just use common sense, and follow good thorough machine shop practices. If you want an extra 125-200 HP, just build it with that much to start with and dont use nitrous. Its not difficult to get that much power out of a 400. I've built some dirt track 400's that made a little over 600 HP with only 11-1 comp. and unported steel Bowtie heads and no roller cam. I think you are underestimating the potential with what you have....
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 10-31-2008, 12:26 AM
TorkMonster400's Avatar
uninteresting default message
 
Last wiki edit: Working with chromed bolts
Last journal entry: A couple of pics of the car
Last photo:
Join Date: Mar 2008
Location: Fort Walton Beach Fl
Posts: 236
Wiki Edits: 4

Thanks: 0
Thanked 0 Times in 0 Posts
CNC-Dude your right on in your response. I was going to go with a little giggle juice with my build but then after reading a lot on the boards I have gone against this idea I'm just going to build my 406 to be a nice street motor with gobs of tire boiling Torque!
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 10-31-2008, 12:31 AM
Registered User
 
Last photo:
Join Date: Mar 2008
Location: Ringgold, Ga.
Posts: 460
Wiki Edits: 0

Thanks: 1
Thanked 17 Times in 16 Posts
Well I tried not to sugar coat it, I just stated the facts! 400's have awesome potential, and can be just as durable and dependable at high HP levels as anything out there, just use your noggin' when you pick your parts.... Thanks for the complement.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 11-03-2008, 06:00 AM
Registered User
 
Last photo:
Join Date: Jun 2008
Location: Mt.Vernon,IN
Posts: 484
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
whhoooooo guys

Your talkin 150-200 shot??? I aint wantin all that.... I'd like to build it to about 10:1 with the comp 280 cam, I=beam 5.7 rods forged, 22cc dish pistons, 062 vortec heads 202/160, stock 400 crank, beef up the valve train and springs, 1.6 roller rockers w/ poly locks. I'd like to atleast gasket match and bowl blend the heads, but I'm kinda scared to do it myself, cuz I'm not that good yet and I hear the vortecs don't have much meat to work with????????? oh and bore .030

I heard that JE makes a coated Hyper piston that will take a 150 shot no problem, but I dunno how true that is.

I was really only plannin on 75-100 at the most.
I think the motor should yeild ~ 450HP then throw a 75-100 shot to it and I got 525-550. Can the Hyper pistons handle it if I stay below 100????????
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 11-03-2008, 11:08 AM
Registered User
 
Last photo:
Join Date: Mar 2008
Location: Ringgold, Ga.
Posts: 460
Wiki Edits: 0

Thanks: 1
Thanked 17 Times in 16 Posts
Its been my experience that hypereutectic pistons aren't very compatible with even modest amounts of nitrous or boost from superchargers. When using either nitrous or boosted power adders, this is one area(pistons) that should not have any corners cut at all. Also, a good safety measure would be the addition of an MSD timing retard module, or timing box to remove set amounts of timing to prevent engine damage. Just running the engine one time on nitrous without taking any timing out of the engine, will be the only time you will run it. Also, as F-Bird has also mentioned, better fuel is also a mandatory requirement for your situation. Neither of these two issues is an option(timing retard or better fuel), they are absolutely required, no ifs, and or buts. Detonation can destroy an engine in a millisecond, even before you hear the first ping, so don't cut any corners in these two areas and you should be fine. You need to follow NOS' recommendations for amount of timing retard, fuel octane, fuel pressure, jetting of nitrous and gas for kit(plate or fogger nozzle) for HP you want to run, engine compression and cam selection to the letter. Any deviation will cause very costly repercussions. Nitrous can be a lot of fun, and provide long term reliability, only if you follow some basic guidelines for prepping your engine and getting your tune-up dialed in as they recommend.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 11-03-2008, 02:00 PM
Registered User
 
Last photo:
Join Date: Jun 2008
Location: Mt.Vernon,IN
Posts: 484
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
chris mays from comp cams

Well I just got off the phone with chris mays from Comp, and He is gonna go through my ideas and help me decide the best way to go. Thanks for your help guys and keep the ideas comming. I'm still open minded.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 11-04-2008, 08:43 AM
Registered User
 
Last photo:
Join Date: Jun 2008
Location: Mt.Vernon,IN
Posts: 484
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
fuel system

OK, I'm VERY un-educated when it comes to nitrous, I've never used it or really even researched it. So, what do you mean when you say set up a fuel system that delivers the correct amount of additional fuel for the NOS??

Will a mechanical pump not work?? Do I need a special carburetor??

OK lets use one of the engines I already have running just for theoretical purposes to give me an Idea of what you mean.

The 355 SBC, KB119 dome hyper's, forged I-beam rods, cast crank, Lunati bracket master II 300 246/246@050, 515/515 lift. 339 heads 76cc 194/150 valves, weiand X-elerater single plane intake, Holley HP 600cfm VS with weak Sec. diaphram spring and 4.5 powervalve and 10" vacuum at idle. (holley mech. fuel pump 6PSI) 185PSI +-5psi on every cylinder

What would I need to do to be able to run a 75-100 horse NOS kit...... I don't even know the difference between a plate kit and a fogger kit so please be as detailed as possible.

I have a guy thats tryin to sell me the hose and soelenoid, purge valve, ect for $20 bucks and a bottle for another $10. Its my brother in law, He bought a 99 f-bird with a 3.8 and a 75hp kit
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 11-04-2008, 10:20 AM
DaSouthWon's Avatar
I put up the tools against$300
 
Last photo:
Join Date: Apr 2006
Location: Memphis,Tennessee
Age: 36
Posts: 684
Wiki Edits: 0

Thanks: 0
Thanked 3 Times in 3 Posts
OK, basics first. Think of nitrous as condensed or compressed air being sprayed into your cylinders. When it goes in to the cylinder it becomes uncondensed or uncompressed. Suddenly you have a whole lot of air molecules that need an equal amount of fuel to maintain a safe air/fuel ratio. The "dangerous" thing about nitrous is the very easy ability to create a lean condition. As I'm sure you know, a lean condition on a NA motor creates heat. Heat that, even without nitrous, can melt pistons. When you add nitrous to the mix, you run the possibility of doing the same thing, only with a magnifying glass on it. There are basically two kinds of nitrous systems, wet and dry. Wet nitrous systems use an enrichment injector to spray extra fuel in with the nitrous. These systems are usually safer than the dry systems, which spray only nitrous, and are easier to tune. The wet system takes a little longer to install, but can be used with NA or forced injection. Dry systems are easy to install, and are best suited for fuel systems that have a fuel return line to the tank like a fuel injected engine. Dry systems are a bad idea on forced induction.

Sufficient fuel pressure is very important. Some people make a T in the factory fuel line and pray that it works. Bad idea. Your fuel pump was designed to supply a sufficient amount of fuel for the motor to run under normal conditions. When you T off the line to run to a fuel nozzle for nitrous the biggest and most likely problem you will run into is a sudden drop in fuel pressure when the nozzle opens. The pump simply cant keep up with the demand, but the nitrous can. I've seen a lot of people add a high volume fuel pump in hopes of fixing this problem, and in theory it seems like it would work. However, even if the larger pump can flow 300 LPH unrestricted, it can't push 300 LPH through a factory fuel line. The line is simply too small in diameter to flow enough fuel through it. Think of pouring oil through a funnel and having to stop to let the level drop before you can add more, its because the spout on the funnel is too small to flow enough out to keep up with what your pouring in. So, the best way to remedy this problem is with a dedicated fuel pump and line from the tank to the NOS system.

Know the maximum amount of fuel you can get into the engine before you ever think about how much nitrous to add. Not knowing this equation is a recipie for disaster if you add too much, and your leaving hp on the table if you add too little. It's much more than adding parts, but its not difficult to do it right if you just take your time and are careful.

Last edited by DaSouthWon; 11-04-2008 at 02:32 PM.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 11-05-2008, 02:37 PM
Registered User
 
Last photo:
Join Date: Jun 2008
Location: Mt.Vernon,IN
Posts: 484
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
the right fuel

F BIRD,
are you saying you just run the 110 or 114 octane in your nitrous fuel cell or do you run it in both tanks??

Could I just run the 93 in the regular tank and put some racing fuel in the seperate nos fuel cell?? With my CR bein what it is ~9.5:1 or so, could I just use 102 octane cuz I can get it locally for $4 a gallon
Reply With Quote Quick reply to this message

Recent Engine 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:
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
Compression question for the Pro engine builders.. Axelrod Engine 14 01-16-2007 11:29 AM
351 windsor running rich ???? ve3ham Engine 19 08-08-2005 01:48 PM
Compression 4x4vandale Engine 5 10-09-2003 12:59 AM
High compression ratio pistons invincible Engine 6 09-22-2003 11:16 PM
compression calculation gabledawg Engine 4 03-06-2003 04:13 PM


All times are GMT -6. The time now is 10:35 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.