Go Back   Third Generation F-Body Message Boards > Tech Boards > Tech / General Engine
Sign in using an external account
Register Forgot Password?

Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!

Welcome to ThirdGen.org!
Welcome to ThirdGen.org.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join the ThirdGen.org community today!


Reply
 
Thread Tools Search this Thread
Old 10-23-2009, 08:13 PM   #1
Supreme Member
 
TPI-Formula350-'s Avatar
 
Join Date: Aug 2003
Location: Long Island New York
Posts: 1,193
Car: 89 Formula 350
Engine: 385 SuperRam Forged/Roller
Transmission: 700R4-3000 Stall-lockup
Axle/Gears: BW 9 Bolt 3:70

Classifieds Rating: (0)
XE284 Base timing

just wondering what you guys are running for base timing with a comp XE284 cam? I'm running 18* BTDC does that sound about right? This is in a 406 with Brodix 200IK heads...I had it dyno tuned on 8/1/09 and wasnt impressed with the numbers.. to add insult to injury the #4 piston broke just after the tune..This motor only had 50 miles on it.. It looks like the Keith Black Hypertecnic? pistons were not gapped correctly by my builder and broke from the ring up.. Anyway I'm dropping the engine off on monday and prob going with forged pistons this time around..So you guys running the XE284 cam please let me know your base timing! Also let me know what you guys think of this dyno sheet...mods in sig below..thanks
__________________

4 bolt 385, 11:1 CR, Brodix 200IK heads,comp 280 XFI (230/236 .576/.571)Comp Roller lifters,SuperRam/Edelbrock hi flo lower,Holley 52mm TB,30lb SVO,CP Forged Pistons,Eagle Forged Rods,Eagle 4340 Forged Crank,Comp Magnum push rods,1:6RR,SLP 1 3/4 Headers, Banks 3" Catback,3000 Stall,Shift kit,3:70 Gears LS1 DS,Holley 255FP,AFPR,March under drive pullies.MSD Blaster coil.AC/Smog Delete Pullies.Custom CAI,Mod MAF,Prominator(prom eliminator).SSM Sub frame,Hotchkis 1" drop springs,Hotchkis STB,UMI LCARBs,467FWHP 517FWTQ
TPI-Formula350- is offline vBGarage Page   Reply With Quote
Old 10-23-2009, 09:30 PM   #2
Supreme Member
 
Join Date: Sep 1999
Location: Philly, PA
Posts: 5,803

Classifieds Rating: (0)
Re: XE284 Base timing

First off, I'll say that you are brave for trying that cam in a modest EFI engine. It's more than a bit on the big side to work with that intake and it's got a fairly tight LSA to work with EFI.

I think it's likely the reason your chassis dyno numbers are a little lower than you expected. By the time the cam comes to life the intake system is all done. A combination mismatch situation. If I may offer a suggestion, you could probably make more power with that combo on at least 10* less duration.

The KB hypers are very sensitive to top ring gap, but it's more than likely detonation that let to #4s demise. So be aware you might have encountered heavier detonation that you realized. Or a combination of modest detonation and too tight a top ring gap, as you mentioned might be the case.

Timing.... with EFI why are you worried about your base timing? All the magic is in the timing table which is completely tunable against RPM, load, throttle position, etc. Everything is your base timing plus what's in the timing map. 18* initial doesn't mean much without knowing how much the chip is adding at various RPMs, throttle positions, etc.

Last edited by Damon; 10-23-2009 at 09:33 PM.
Damon is offline vBGarage Page   Reply With Quote
Old 10-23-2009, 10:39 PM   #3
Supreme Member
 
TPI-Formula350-'s Avatar
 
Join Date: Aug 2003
Location: Long Island New York
Posts: 1,193
Car: 89 Formula 350
Engine: 385 SuperRam Forged/Roller
Transmission: 700R4-3000 Stall-lockup
Axle/Gears: BW 9 Bolt 3:70

Classifieds Rating: (0)
Re: XE284 Base timing

Well you might be on to something...I was thinking the Super Ram made power to almost 6500RPMs but after doing afew searches it seems to make max power at 5400RPMs. The comp XE284 cam I have in my 406 is advertised to make power from 2300-6500RPMs so it looks like I'll never get to use the top end range of the cam...So I serious considering having the engine made into a roller setup...So does anyone have suggestions on a better cam for my setup???




Quote:
Originally Posted by Damon View Post
First off, I'll say that you are brave for trying that cam in a modest EFI engine. It's more than a bit on the big side to work with that intake and it's got a fairly tight LSA to work with EFI.

I think it's likely the reason your chassis dyno numbers are a little lower than you expected. By the time the cam comes to life the intake system is all done. A combination mismatch situation. If I may offer a suggestion, you could probably make more power with that combo on at least 10* less duration.

The KB hypers are very sensitive to top ring gap, but it's more than likely detonation that let to #4s demise. So be aware you might have encountered heavier detonation that you realized. Or a combination of modest detonation and too tight a top ring gap, as you mentioned might be the case.

Timing.... with EFI why are you worried about your base timing? All the magic is in the timing table which is completely tunable against RPM, load, throttle position, etc. Everything is your base timing plus what's in the timing map. 18* initial doesn't mean much without knowing how much the chip is adding at various RPMs, throttle positions, etc.
TPI-Formula350- is offline vBGarage Page   Reply With Quote
Old 08-20-2010, 07:29 PM   #4
Member
 
elano's Avatar
 
Join Date: Mar 2007
Location: Georgia
Posts: 192
Car: 86 IROC-Z, 82 z28
Engine: 383 Stroker
Transmission: TH-350
Axle/Gears: 3.73 Torsen, 4.56 Auburn

Classifieds Rating: (2)
Re: XE284 Base timing

I have my xe284 in a 383 stroker and shift at 5500rpm. I run 16* initial advance but the cam really likes it higher, around 20 +/-.
elano is offline vBGarage Page   Reply With Quote
Old 08-22-2010, 01:49 PM   #5
Senior Member
 
F-BIRD'88's Avatar
 
Join Date: Sep 2001
Location: Ontario, Canada
Posts: 5,823
Car: 1988 Firebird S/E
Engine: 406Ci Vortec SBC
Transmission: TH-350/3500stall
Axle/Gears: 7.5" Auburn 4.10 Posi-Traction

Classifieds Rating: (0)
Re: XE284 Base timing

I run the xe284H and KB hyper pistons in my 406. no problems with the pistons.
I run the timing locked out 34-36deg at idle and max advance. (Carbed)

Your cr is too high and the ring gap was tight. Find another engine builder who has a clue. The xe284H is a poor match to a super ram EFI.
If you want to run a Xe284 cam get a tunnel ram style EFI manifold (stealth ram, ram jet)
or a single plane short runner manifold (Mini ram) or convert a dual plane performer rpm manifold to efi.

If you had flat tops and 64cc head the cr will be too high.
With a 64cc head on a 406 use the -18cc KB174 or the -22cc KB168 pistons. Read the KB directions and set the ring end gaps as recomended.
Find a engine builder who can read.
Then dyno the motor on a real dyno.

For the superram try 226-230 on 112 with a high rocker ratio
F-BIRD'88 is offline vBGarage Page   Reply With Quote
Old 08-22-2010, 02:28 PM   #6
Supreme Member
 
Orr89RocZ's Avatar
 
Join Date: Sep 2003
Location: Houston, Texas
Posts: 15,627
Car: 89 Iroc-z
Engine: Twin Turbo 401
Transmission: TH400
Axle/Gears: 4th gen 10 bolt 2.73's

Classifieds Rating: (16)
Send a message via AIM to Orr89RocZ
Re: XE284 Base timing

Old thread...
He doesnt even have this combo any more Put it on a 383 with 280xfi cam and it made near 470 hp on motor around 5500-5600 rpm
__________________

1989 Twin Turbo IROC-Z
"Twin Turbo 401 Buildup Pics "
"FQuick Garage"
9.86 at 141 mph 14psi, pump gas street tune
Orr89RocZ is offline vBGarage Page   Reply With Quote
Old 08-22-2010, 02:28 PM
ThirdGen
1992 Camaro




Paid Advertisement


Reply

Go Back   Third Generation F-Body Message Boards > Tech Boards > Tech / General Engine

Tags
200ik, 284, 406, base, brodix, cam, comp, efi, heads, pistons, recommended, rpm, shift, timing, xe, xe284
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not 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 Off
Pingbacks are Off
Refbacks are Off

 


1982 Camaro '82 || 1983 Camaro '83 || 1984 Camaro '84 || 1985 Camaro '85 || 1986 Camaro '86 || 1987 Camaro '87 || 1988 Camaro '88 || 1989 Camaro '89 || 1990 Camaro '90 || 1991 Camaro '91 || 1992 Camaro '92


All times are GMT -5. The time now is 03:26 PM.


Powered by vBulletin® Version 3.7.5
Copyright ©2000 - 2012, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.5.2
All content copyright © 1997 - 2012 ThirdGen.org. All rights reserved. No part of this website may be reproduced without the expressed, documented, and written consent of ThirdGen.org's Administrators.

Emails & Contact Details