7.3 idi max boost with head studs?
Thread Starter
|
New User
Joined: Dec 2014
Posts: 13
Likes: 0
7.3 idi max boost with head studs?
Just like the title says. What is the max boost I would be able to run safely if I studded the heads? I don't want to touch the bottom end if I don't have to. My end goal is to get 200+ hp to the wheels. I'm still in the planning stages of building my truck so I want to gather all the information I can. Thanks in advanced
-Kolby
-Kolby
Logistics Pro
Joined: Jul 2012
Posts: 3,602
Likes: 132
From: Centerville TN
In not sure about studs, but by numbers, my truck is supposed to be about 200 at he rear wheels. I'm running an 80cc IP with a factory turbo and upgraded exhaust. I don't have dyno numbers, but it will out pull a stock first gen powerstroke and hang pretty good with my uncle's 99 stroke. I'm running 12 psi boost max.
Senior User
Joined: Jan 2011
Posts: 184
Likes: 0
From: Hope,in
Kolby.,..in addition to head studs use the R&D camshaft, it bleeds off some of the compression for higher boost, i myself am going this direction, as well as re ring kit in bottom end, re ring kit is the cheap part of the horsepower equation but should never be overlooked, the cam is not priced very bad either, the most expense you willhave is in the pump and turbo
Senior User
Joined: Jan 2011
Posts: 184
Likes: 0
From: Hope,in
What pump and turbo is he running
Senior User
Joined: Jan 2009
Posts: 353
Likes: 0
From: elk plain, wa
https://www.ford-trucks.com/forums/1342155-some-dyno-numbers-and-turbo-info.html
This is the thread that justin from R&D started on my brothers truck
This is the thread that justin from R&D started on my brothers truck
Trending Topics
i ain't rite
Joined: Mar 2005
Posts: 65,591
Likes: 5,619
From: Marlboro Mental Hospital.
my 88 with 949,000+ miles on it has been running 12 to 16 lbs boost for the past 490,000 miles and has never been opened up. it will run over 16 lbs, if i really load it up, but i try to keep it under 16.
i know some others that ran 20+ lbs boost with no problems. but it is recommended to run studs if you are going to run over 15 lbs boost.
i know some others that ran 20+ lbs boost with no problems. but it is recommended to run studs if you are going to run over 15 lbs boost.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 6 Best Deals Available on New Fords & Lincolns Right Now
Brett Foote
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Verdad Gallardo
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
Fleet Mechanic
Joined: Oct 2012
Posts: 1,943
Likes: 21
I would say that with head studs torqued correctly your limiting factor would be your EGT's. An intercooler and large exhaust could help greatly with this. With this you should be able to max out the stock pump.
Remember, it is quite possible to make more power on lower boost numbers.
Lead Driver
Joined: Apr 2008
Posts: 6,945
Likes: 13
Those numbers are very impressive. If I remember correctly the block has been reinforced to help hold the power (mainly crazy torque numbers). Not sure if the OP wants to invest that much.
I would say that with head studs torqued converter your limiting factor would be your EGT's. An intercooler and large exhaust could help greatly with this. With this you should be able to max out the stock pump.
Remember, it is quite possible to make more power on lower boost numbers.
I would say that with head studs torqued converter your limiting factor would be your EGT's. An intercooler and large exhaust could help greatly with this. With this you should be able to max out the stock pump.
Remember, it is quite possible to make more power on lower boost numbers.
200whp is easy, fresh IP / injectors (doesnt have 280k on em) with decent intake /exhaust, and really any one of the "stock" turbos. Shouldnt need studs, but id wager the cam would help some, as would an IC
Fleet Mechanic
Joined: Oct 2012
Posts: 1,943
Likes: 21
Stock IDIT bottom end, stock compression, everything. Might have a girdle and main studs.
200whp is easy, fresh IP / injectors (doesnt have 280k on em) with decent intake /exhaust, and really any one of the "stock" turbos. Shouldnt need studs, but id wager the cam would help some, as would an IC
200whp is easy, fresh IP / injectors (doesnt have 280k on em) with decent intake /exhaust, and really any one of the "stock" turbos. Shouldnt need studs, but id wager the cam would help some, as would an IC
94 IDIT rebuilt 20K
Stock compression
R&D Girdle Kit
R&D Stage 1 cam
Head Studs@150ft/lbs
RD2-90
R&D Prototype Stage 1 injectors
R&D Stage 3 Turbo Kit
HX35 12cm housing
The only real structural mod is the Girdle Kit and then the head studs. I am sure the Stage 1 cam helps some since it would reduce the dynamic compression ratio some, though I do not know by how much.
The stock 7.3 IDI Turbo engine was rated at 190hp and 388ft/lbs at the crank. Drive-line losses vary, but with a 20% loss it would give you 152hp at the wheels stock. To get 200 at the wheels you would need 250hp at the crank, a 60hp increase.
To be honest, I don't know what the factory boost numbers are, but wouldn't think it would take much more to get you to the 250chp number. Like hairyboxnoogle said, I would think that with the proper intake/exhaust to allow more air in/out as well as better turbo function you should be able to get close and also allow you to turn up your pump some. If you added an IC you would be able to turn the pump up even more. While the IC would cause your boost numbers to drop, it should make more power at the lower boost levels and keep your EGTs in check....thus allowing you to add more fuel.
Lead Driver
Joined: Apr 2008
Posts: 6,945
Likes: 13
Yes, it was pretty much a stock block/rotating assembly set up. Here is what is listed in the thread:
94 IDIT rebuilt 20K
Stock compression
R&D Girdle Kit
R&D Stage 1 cam
Head Studs@150ft/lbs
RD2-90
R&D Prototype Stage 1 injectors
R&D Stage 3 Turbo Kit
HX35 12cm housing
The only real structural mod is the Girdle Kit and then the head studs. I am sure the Stage 1 cam helps some since it would reduce the dynamic compression ratio some, though I do not know by how much.
The stock 7.3 IDI Turbo engine was rated at 190hp and 388ft/lbs at the crank. Drive-line losses vary, but with a 20% loss it would give you 152hp at the wheels stock. To get 200 at the wheels you would need 250hp at the crank, a 60hp increase.
To be honest, I don't know what the factory boost numbers are, but wouldn't think it would take much more to get you to the 250chp number. Like hairyboxnoogle said, I would think that with the proper intake/exhaust to allow more air in/out as well as better turbo function you should be able to get close and also allow you to turn up your pump some. If you added an IC you would be able to turn the pump up even more. While the IC would cause your boost numbers to drop, it should make more power at the lower boost levels and keep your EGTs in check....thus allowing you to add more fuel.
94 IDIT rebuilt 20K
Stock compression
R&D Girdle Kit
R&D Stage 1 cam
Head Studs@150ft/lbs
RD2-90
R&D Prototype Stage 1 injectors
R&D Stage 3 Turbo Kit
HX35 12cm housing
The only real structural mod is the Girdle Kit and then the head studs. I am sure the Stage 1 cam helps some since it would reduce the dynamic compression ratio some, though I do not know by how much.
The stock 7.3 IDI Turbo engine was rated at 190hp and 388ft/lbs at the crank. Drive-line losses vary, but with a 20% loss it would give you 152hp at the wheels stock. To get 200 at the wheels you would need 250hp at the crank, a 60hp increase.
To be honest, I don't know what the factory boost numbers are, but wouldn't think it would take much more to get you to the 250chp number. Like hairyboxnoogle said, I would think that with the proper intake/exhaust to allow more air in/out as well as better turbo function you should be able to get close and also allow you to turn up your pump some. If you added an IC you would be able to turn the pump up even more. While the IC would cause your boost numbers to drop, it should make more power at the lower boost levels and keep your EGTs in check....thus allowing you to add more fuel.
Stock turbos were wastegated at 7.5-9psi and have a smashed downpipe / restrictive muffler. They were also calibrated at like 62cc, a stock 7.3 pump in good shape should flow 80-85cc turned all the way up. 80cc x 2.7= 216whp. For a non intercooled / stock turbo setup i would use a more conservative 2.5whp/cc which still puts you at straight up 200whp.
A really efficient setup should run around 2.7whp /cc injected. An inefficient setup would be around 2.4
All that said, lots of guys have ran maxxed stocker and 90cc pumps for ages with no headgasket problems. I was seeing 22+ with the restrictive hx35.
Logistics Pro
Joined: Jul 2012
Posts: 3,602
Likes: 132
From: Centerville TN
I see 12psi loaded and rarely hit 1100egts. But I have found that timing is everything. Mess with the fuel,retime. My IP gave me some problems awhile back. Truck turned into a smokey slob. Egts went up pretty bad. Timing was off. 1\2 a degree makes all the difference sometimes.
Fleet Owner
Joined: Jul 2006
Posts: 20,394
Likes: 852
From: Mi'kma'ki
iirc oem boost of the factory unit is set around 7 psi.
chip truck hits 14 psi @ a cool max of 900-1000 egt.
( @ 8k lb curb weight,she can hit 80 mph with ease well within a 1/4 mile...theoretically
)
log truck's wg hasn't been messed with and peaks out around 10 psi.runs cool as well of course as both trucks are intercooled.
it's not hard to surpass the first gen PSD's power.
keep in mind,the "stage 1 cam" will cost you power over oem and for sure the torque cam in the powerband where you'll be spending 95% of your time on the street.....unless you've got an f-super duty.then it's probably a match made in heaven at 50+ mph with a od trans.
imho you don't want a "stage 1 cam" but it's great to have available for those who might need one.i think the grind Russ sells should be the one titled stage 1 with Justin's labeled stage 3.calling an upper rpm power band grind a stage 1 is misleading.
chip truck hits 14 psi @ a cool max of 900-1000 egt.
( @ 8k lb curb weight,she can hit 80 mph with ease well within a 1/4 mile...theoretically
)log truck's wg hasn't been messed with and peaks out around 10 psi.runs cool as well of course as both trucks are intercooled.
it's not hard to surpass the first gen PSD's power.
keep in mind,the "stage 1 cam" will cost you power over oem and for sure the torque cam in the powerband where you'll be spending 95% of your time on the street.....unless you've got an f-super duty.then it's probably a match made in heaven at 50+ mph with a od trans.
imho you don't want a "stage 1 cam" but it's great to have available for those who might need one.i think the grind Russ sells should be the one titled stage 1 with Justin's labeled stage 3.calling an upper rpm power band grind a stage 1 is misleading.
Fleet Mechanic
Joined: Oct 2012
Posts: 1,943
Likes: 21
HD250....I understand what you are saying about different can profiles. I have a hot cam profile in my track car that causes me to lose torque down low as a trade off for higher rpm power.
You mentioned the torque cam. Were you referancing the type4 torque cam. My understanding of its profile is that it increases low end torque in NA engines to help towing characteristics. Am I mistaken? Looking at dyno graphs of the torque cam it looks like it peaks earlier than the R&D cams.
Can you expand on this?
You mentioned the torque cam. Were you referancing the type4 torque cam. My understanding of its profile is that it increases low end torque in NA engines to help towing characteristics. Am I mistaken? Looking at dyno graphs of the torque cam it looks like it peaks earlier than the R&D cams.
Can you expand on this?