Welcome to the North American Subaru Impreza Owners Club Friday March 29, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Built Motor Discussion

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

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, free of charge, 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, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 06-29-2020, 01:43 PM   #1
WRXXXED
Scooby Specialist
 
Member#: 432652
Join Date: Oct 2015
Location: Gap, PA
Vehicle:
2010 Subaru WRX STI
61K (Gray)

Default ARP 625+ vs Cosworth PR7243 head studs

Getting my engine build together here soon and wondering is there are any differences between the two? I couldn't find anything on the cosworth studs

Both made from 625 tool steel

Both 11mm (arps actually measure at 9.8mm diameter i believe)

Both have a 260,000 tensile strength


So why are the ARPs so popular and more expensive?

Will i be okay to go with the cosworth headstuds for around 500whp?

Engine build is a closed deck, 100mm wiseco pistons, BC I-beam rods, stock heads, and a Garrett 3582r turbo

Thanks for the input
* Registered users of the site do not see these ads.
WRXXXED is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 06-29-2020, 02:44 PM   #2
subydude
Scooby Guru
 
Member#: 80649
Join Date: Jan 2005
Chapter/Region: South East
Location: Columbia, SC
Vehicle:
2000 2.5 Auto-X RSTi
Sparkly

Default

You don't even need 625 for that level. You could do regular ARP 2000's and be fine. Maybe L19's if you're really worried.

Regarding the question, I'd wager because ARP has a much better name, is up front about their product, gives good instructions, and has a reasonable reputation for warranty. Cosworth on the other hand, has a good name.......and that's it in the Subaru arena.
subydude is offline   Reply With Quote
Old 07-01-2020, 10:02 AM   #3
BlackFighter
Scooby Specialist
 
Member#: 193940
Join Date: Nov 2008
Location: Philly
Vehicle:
2004 WRX STI Black
RalliSpec Shortblock

Default

Ya, ARP is more hands on with subie owners then cosworth and willing to spend the time with us. Also probably has something to do with marketing.

Also ARP lives and bleeds bolts, that is the main product of their business. So most of R&D goes to bolts. Cosworth has a lot of different products on the market so they can not concentrate as much on bolts as ARP dose.
BlackFighter is offline   Reply With Quote
Reply

Thread Tools
Display Modes

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
Forum Jump

All times are GMT -4. The time now is 08:08 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.