6.9l build
Thread Starter
|
New User
Joined: Nov 2013
Posts: 6
Likes: 0
From: Soda Springs,CA
6.9l build
First off I know there is a lot of info on this but looking for some more input... I just bought an 87 6.9l motor and plan on doing a full build. Pistons, rods, moose pump, turbo, etc. Not trying to get too crazy but definitely want to smoke some newer stock diesels. Anyone have input for me? Also gonna be looking for performance parts if people with experience can steer me in the right direction that would be greatly appreciated. TIA
Thread Starter
|
New User
Joined: Nov 2013
Posts: 6
Likes: 0
From: Soda Springs,CA
Looking for 300+. I know 250 is easily attainable with turbo so I would like to push it a little more... Still needs be be a daily so not too crazy. It sounds like R&D is going to be the way to go. Looking for people with experience building and driveablilty afterwards and what I should be aware of and avoid...
Lead Driver
Joined: Apr 2008
Posts: 6,945
Likes: 13
Biggest drawback you have set for yourself is the 6.9. There is no easy or cheap way around the small headbolts. I was quoted a grand to go from 7/16 to 1/2 or 9/16" holes. The cheaper option by about half, is a heavy cut on the pistons, but the consensus is people dont care for how the idi runs with 16/17:1 compression. Some have tried the prototype headgasket, so that might be the best route, then you can decide for yourself whether you can live with the drivability or not, and if not, swap gaskets and turn it down.
Postmaster
Joined: Dec 2011
Posts: 3,860
Likes: 7
I think with a 6.9, you'll need more than 7/16 studs to try to make that HP. You will pretty much require 1/2" studs at least, or 9/16 bolts.
There aren't many IDIs out there /period/ running over about 210-220HP, and R&D's your best bet for parts.
There aren't many IDIs out there /period/ running over about 210-220HP, and R&D's your best bet for parts.
Posting Guru
Joined: May 2015
Posts: 2,036
Likes: 5
Look at the stock head bolts for a 6.0 there huge but stretch in an instant yet guys with the same size but a head stud are pushing crazy boost with really good luck.
87 6.9 is definitely the motor to build. Although it wouldn't be much to just snag a set of heads and use a 85.5-86 block
Lead Driver
Joined: Apr 2008
Posts: 6,945
Likes: 13
Theres a couple reports of fresh 6.9s blowing gaskets with the good ARP studs only running a 90cc pump and a S258 and low 20s for boost. 7/16" is just too small of a fastener for the idi's "goofy" 5 bolt per cylinder pattern. A 90cc and 258 would net you 220-240hp at the wheels.
Trending Topics
Postmaster
Joined: Dec 2011
Posts: 3,860
Likes: 7
Theres a couple reports of fresh 6.9s blowing gaskets with the good ARP studs only running a 90cc pump and a S258 and low 20s for boost. 7/16" is just too small of a fastener for the idi's "goofy" 5 bolt per cylinder pattern. A 90cc and 258 would net you 220-240hp at the wheels.
OP, Go check out the area of a 7/16-14 fastner vs a 1/2-13 fastner. Hint: the the actual cross section is less than 7/16 or 1/2".
You'll find that even ARP studs just aren't that strong in total clamping force with such a small cross section.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Postmaster
Joined: Feb 2003
Posts: 3,441
Likes: 5
From: Muskegon, MI (home)
First off I know there is a lot of info on this but looking for some more input... I just bought an 87 6.9l motor and plan on doing a full build. Pistons, rods, moose pump, turbo, etc. Not trying to get too crazy but definitely want to smoke some newer stock diesels. Anyone have input for me? Also gonna be looking for performance parts if people with experience can steer me in the right direction that would be greatly appreciated. TIA
Thread
Thread Starter
Forum
Replies
Last Post
6inarowmakeitgo
Ford Inline Six, 200, 250, 4.9L / 300
83
Nov 11, 2012 07:16 AM
Royson12
Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
16
Feb 21, 2008 04:23 AM