Brought to you in part by:

.

Tools & Supplies by Eastwood

  Mustangsandmore Forums
  Ford Racing
  Shift Point?

Post New Topic  Post A Reply
profile | register | preferences | faq | search

UBBFriend: Email This Page to Someone! next newest topic | next oldest topic
Author Topic:   Shift Point?
65_289
Gearhead

Posts: 396
From:
Registered: Jul 2001

posted 01-14-2002 09:45 PM     Click Here to See the Profile for 65_289   Click Here to Email 65_289     Edit/Delete Message   Reply w/Quote
What is the best rpm to shift at? Is it right at peak hp? 500 rpm after peak hp? Or do the gear ratios of the tranny come in to play?

------------------
1965 Coupe, Tremec 3550, Steeda Tri-Ax, Cable Clutch conversion, 3.25 gears, Biondo Line Lock, Ford XB3 longblock, x303 heads, B-Cam, 9:1 comp., Tri-y headers, cut-outs, Ford Racing high-torque mini-starter, Pertronix Ignitor & Flamethrower coil, 650 double pumper, Edelbrock RPM intake, K&N air, Holley electric fuel pump & AFPR, dual 2-chamber Flowmasters, Summit 3-way fronts, Rancho 5-way rears, 5-leaf springs, Chrome Export Brace, Griffen Radiator, Comp. Eng. subs.

IP: Logged

65_289
Gearhead

Posts: 396
From:
Registered: Jul 2001

posted 01-14-2002 10:38 PM     Click Here to See the Profile for 65_289   Click Here to Email 65_289     Edit/Delete Message   Reply w/Quote
Nevermind. I found a website that calculates them for you.

http://www.prestage.com/carmath/dynochart.asp

IP: Logged

V8 Thumper
Gearhead

Posts: 603
From: Orange, Ca. United States of America
Registered: Dec 2001

posted 01-15-2002 12:40 AM     Click Here to See the Profile for V8 Thumper   Click Here to Email V8 Thumper     Edit/Delete Message   Reply w/Quote
Bitchin'! There's a buncha cool links/calculators there, I wonder how accurate some of them are. Not a bad starting point, I imagine

IP: Logged

Moneymaker
Administrator

Posts: 11493
From: Lyons, IL, USA
Registered: May 99

posted 01-15-2002 12:59 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
We have found that "GENERALLY" 4 to 500 RPM over the point that peak HP is achieved is a good place to make gear changes in a 6500 RPM or less engine. The higher the RPM the larger the spread.

------------------
Alex Denysenko
Co-Administrator and Moderator
NHRA/IHRA/SRA member
NHRA and IHRA SS/LA National Record Holder '00, '01, & '02
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28
Part time secret agent license #0089
US Class Nationals link

IP: Logged

65_289
Gearhead

Posts: 396
From:
Registered: Jul 2001

posted 01-15-2002 02:00 PM     Click Here to See the Profile for 65_289   Click Here to Email 65_289     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by Moneymaker:
We have found that "GENERALLY" 4 to 500 RPM over the point that peak HP is achieved is a good place to make gear changes in a 6500 RPM or less engine. The higher the RPM the larger the spread.


I just wonder how good Ford Racing puts these motors together. I'd hate to take it to 6500, only to have some cheap rod bolt decide to take a dump.

IP: Logged

Kyle
Journeyman

Posts: 64
From: Sumner, WA USA
Registered: Dec 2001

posted 01-16-2002 12:32 PM     Click Here to See the Profile for Kyle   Click Here to Email Kyle     Edit/Delete Message   Reply w/Quote
Did anybody else use this calculator? I put in the torque amounts estimated by dyno 2000 for my motor, added the C4 gearing, and it came bace saying that I need to shift at 8500 rpm! Peak HP is at 6500, and torque peaks at 5000rpm. So either Dyno 2000 is screwed up, or something isn't being accounted for.

IP: Logged

rd400d
Journeyman

Posts: 7
From:
Registered: Jan 2002

posted 01-20-2002 11:52 AM     Click Here to See the Profile for rd400d     Edit/Delete Message   Reply w/Quote
I've never drove a really fast car (like 11's or quicker) but i've rode bikes since i was a kid and i always knew when to shift kinda like a harmony you have with the motor. Plus i'd imagine youd shift when the motor stops pulling or reaches that sound in the power band.

IP: Logged

Mario428
Journeyman

Posts: 15
From: Charlottetown, PEI, Canada
Registered: Nov 2001

posted 01-20-2002 12:48 PM     Click Here to See the Profile for Mario428   Click Here to Email Mario428     Edit/Delete Message   Reply w/Quote
The Prestage.com calculator was a waste of 2 minutes of my life.
7500 rpm for a 6500 rpm max motor. Their calculations are based on a bogus formula using torque loss.

IP: Logged

All times are ET (US)

next newest topic | next oldest topic

Administrative Options: Close Topic | Archive/Move | Delete Topic
Post New Topic  Post A Reply
Hop to:

Contact Us | Mustangsandmore Front Page

Copyright 2002, Steve LaRiviere


Ultimate Bulletin Board 5.47d

Amazon Honor System Click Here to Pay Learn More

[Build a free Mustangsandmore.ws Home Page!]

[About M&M][Acronym Guide][Calendar of Events][Chat Room][Classified Ads] [Links]

[Members' Photos] [M&M Mug Shots] [Technical Articles][Ford Parts Number Deciphering

[ Mustangsandmore.com Bookstore] [Advertise on Mustangsandmore.com] [Mustangsandmore.com T-Shirts]