autox
[Top] [All Lists]

Re: HP & air fuel metering

To: "Ron Chapman" <CHAPMANR@calbt.com>, autox@autox.team.net
Subject: Re: HP & air fuel metering
From: Vince Bly <vbly@pop200.gsfc.nasa.gov>
Date: Wed, 27 Feb 2002 17:43:29 -0500
At 01:26 PM 2/27/02 -0800, Ron Chapman wrote:
>Hi gang, I have two questions for the technically minded:
>
>1) What's a good rule of thumb for converting from wheel hp to crank hp?
>
>2) I'm trying to do some dyno tuning on my SP CRX.  We've done a baseline 
>run without an air fuel meter being used.  The new engine pieces have been 
>bolted on, and I know we need to use an air fuel meter for the 
>tinkering.  I'm still using stock injection, so its not like we'll be 
>doing any mapping, just making sure that the new pieces have moved us 
>forward, not back, and seeing what effect timing changes have.
>
>The question is, would an Autometer air fuel type gauge which attaches to 
>the stock wiring harness be sufficient? Or, do I really need to add a bung 
>to the header and let the shop use their megabuck Motec device?  It seems 
>to me that with stock injection, the simple splice in should suffice due 
>to the limited changes we can make.
>
>Thanks,
>
>Ron Chapman
>
>85 CRX CSP
>91 Civic HS
>99 Miata CS
=====================================

Ron,

         Relative to your first question, I worked with a company that
runs a Dynojet chassis dyno that, in turn, works with an engine shop
with a direct engine dyno.  They say that on most of the front wheel
drive cars where they have tested the engine on both dynos, the
difference is approximately 15%.  So, multiplying the wheel hp by
1.15 to estimate the crank hp will get you close.

                                 Vince Bly  #49 STS

///  unsubscribe/change address requests to majordomo@autox.team.net  or try
///  http://www.team.net/mailman/listinfo
///  Partial archives at http://www.team.net/archive


<Prev in Thread] Current Thread [Next in Thread>