how much will the upgrade add?
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 320
Likes: 0
From: Dallas, Texas
how much will the upgrade add?
I'm getting ready to do the big upgrade...Holley 390, Offy Intake, EFI exaust, and Walker Downpipe.
I know this topic has been beat to death, but i was just wondering HOW MUCH it will add. I'm currently running the old 1bbl Carter tht they came with back in the day, with the stock intake and stock exaust manifold. I rebuilt the engine about a year ago, so thats in good shape.
I know this topic has been beat to death, but i was just wondering HOW MUCH it will add. I'm currently running the old 1bbl Carter tht they came with back in the day, with the stock intake and stock exaust manifold. I rebuilt the engine about a year ago, so thats in good shape.
Postmaster
Joined: May 2002
Posts: 3,241
Likes: 3
From: Broken Arrow, OK
You're right, it's been beat to death. Nobody knows how much it will add because there are only a few of us (you can count 'em on one hand) that have ever had our truck on a dyno. Of those that have dyno'd their trucks, there are no stock numbers to compare to.
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 320
Likes: 0
From: Dallas, Texas
well i didn't expect actual numbers. i was looking for things like "a significant amount" or "its definetly noticable"
not "25.3 horsepower and 30.453 foot pounds of tq gained"
not "25.3 horsepower and 30.453 foot pounds of tq gained"
Elder User
Joined: Sep 2003
Posts: 926
Likes: 3
From: SE, Michigan
I'll try and help out on this subject. I just did my rebuild and its been running for about 3 weeks with the 390 holley, offenhauser dual port intake, EFI exhaust manifolds, walker downpipe, and comp cams 260H. My 300 before the rebuild was tired, weak, had blow by, with over 314,000 miles. So the difference was really noticeable. Since yours is a fresh rebuild it should still be fairly good upgrade. I would say go for it, anything is better than the 1bbl except it was good on gas. I've been trying to drive mine without getting into the secondaires (easier said than done). Hope this helps, let us know if you need any other info because there are a few minor modifications that need to be done when doing this swap. Check my gallery under 300 rebuild for pictures of it.
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 320
Likes: 0
From: Dallas, Texas
thanks 1982fordf100. i saw your other thread about you fresh build, and i saved all your pictures off so i can refer to them later. I'm also glad you gave that diagram about the bracket, because i was kinda worried about what to do about that.
Postmaster
Joined: Mar 2002
Posts: 3,545
Likes: 4
From: Coal Region
i have one dyno sheet from a 95 F150 300/auto that was stock. the other one i have is of a 93 with an exhaust done. the only other ones i know of are urs SS, the same guy w/ the exhaust but now cam and head work and another with a cam and headwork. all are EFI though.
i would say 35-50 hp (probaly 35 ish) would be a good guess for a gain. depending on the tune, how the exhaust is ran and condition of the engine.
or, it'll be noticable...
i would say 35-50 hp (probaly 35 ish) would be a good guess for a gain. depending on the tune, how the exhaust is ran and condition of the engine.
or, it'll be noticable...
Senior User
Joined: Jul 2003
Posts: 311
Likes: 2
From: Nashville
Here's what I noticed after my 1st upgrade [same as what you're about to do]: Very noticable power increase plus a slight increase in gas mileage. Towing a loaded trailer w/ the stock engine it would not think about going past 70mph at full throttle on flat ground; post upgrade it would cruise at 70-75 without breaking a sweat, and easily pull the load till redline. Still had problems towing uphill but switched the 3.09 rear end to a 3.50 and that went away. Lost the 1mpg gain after the rear end swap when towing, but unloaded mileage actually stayed the same.
Bugs to watch for: The carb's throttle linkage often hits the Offy intake, requiring a short spacer under the carb. Be prepared to fabricate a new mounting bracket for the throttle cable [easy], several of us have pics posted of our homebrew brackets. If you get a noticable bog when the secondaries open, change the secondary spring to the BROWN one, this is what 90% of us seem to wind up using. If you have a C6 tranny and want the kickdown function to work you'll need to buy a kickdown cable kit or modify the existing linkage to work [tricky].
Bugs to watch for: The carb's throttle linkage often hits the Offy intake, requiring a short spacer under the carb. Be prepared to fabricate a new mounting bracket for the throttle cable [easy], several of us have pics posted of our homebrew brackets. If you get a noticable bog when the secondaries open, change the secondary spring to the BROWN one, this is what 90% of us seem to wind up using. If you have a C6 tranny and want the kickdown function to work you'll need to buy a kickdown cable kit or modify the existing linkage to work [tricky].
Trending Topics
Tuned
Joined: Jan 2006
Posts: 290
Likes: 1
I rebuilt my I6 this year and installed a Clifford water heater/cooled intake with a Holley390. I used the EFI exhaust with the Walker Y pipe to single stock muffler and tail pipe to the back side of the rear wheel. Nice and quite except around 3-4k, the K&N starts honking like a mad bull. ( I have a cd/radio that sounds good to me. ) I still need to tweek my carb. I want to get the carb setting level so I can adjust the floats. I have a dizzy with vacuum advance, GM HEI module and coil.
I would like to know more about a dyno run. How much does this cost. Where is the closest place to Corvallis Oregon. After I get the carb sorted out I would like to get it dynoed. Any good things to look out for? Any quick adjustments while getting dynoed?
I used the Clifford intake because offy said thier manifold would not fit in a van. It would be nice to compair with the offy dp.
I would like to know more about a dyno run. How much does this cost. Where is the closest place to Corvallis Oregon. After I get the carb sorted out I would like to get it dynoed. Any good things to look out for? Any quick adjustments while getting dynoed?
I used the Clifford intake because offy said thier manifold would not fit in a van. It would be nice to compair with the offy dp.
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