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98 5.0 Mods

Levman74

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Levman74 Enthusiast

Levman74

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Considering some work done to my 98 5.0-to freshen it up as it has intake gasket issues and a couple other minor issues-also to improve performance a little too.

I was looking and found that I can mill the heads a max of .040-now, I wouldnt go this far, keep the compression under 10:1-as stock is 9.4:1. Has anyone done this at all? What about porting? I'm also considering a 75mm throttle body as well as a throttle body spacer, but not sure if the spacer would help with a larger TB.

A few other things I am considering-

Ignition module

Cam/Springs

larger valves

 

Also doing a basic tune-up-I already have an MSD 6A box and coil

Has anyone had problems with the timing chain getting sloppy past 100k? Mine is at 112-

any help is appreciated-thanks

Skyz71 Enthusiast

Skyz71

Posted
Posted
Considering some work done to my 98 5.0-to freshen it up as it has intake gasket issues and a couple other minor issues-also to improve performance a little too.

I was looking and found that I can mill the heads a max of .040-now, I wouldnt go this far, keep the compression under 10:1-as stock is 9.4:1. Has anyone done this at all? What about porting? I'm also considering a 75mm throttle body as well as a throttle body spacer, but not sure if the spacer would help with a larger TB.

A few other things I am considering-

Ignition module

Cam/Springs

larger valves

 

Also doing a basic tune-up-I already have an MSD 6A box and coil

Has anyone had problems with the timing chain getting sloppy past 100k? Mine is at 112-

any help is appreciated-thanks

 

 

 

 

bbk actually makes a killer tb for the 5.0L, it's 80mm and it's pretty much a bolt on application from what i've been told. I also have a 5.0L and i've actually gotten more power from simple things with air induction and exhaust. Some of the best investments you could make can be a new PCM, exhaust, and an intake kit with a new MAF sensor. The spacer, especially at higher altitudes (i.e colorado) and with this engine, won't do much at all. As far as everything else like the milling the heads, and other top end work, i haven't gotten that far either so I'm interested in any responses as well. :bs:

 

Jeff (skyz71)

Levman74 Enthusiast

Levman74

Posted
  • Author
Posted

Well, I found a 75mm TB on ebay for about $100-so thats what sparked my interest-i'll look into that unit also. Right now I have a full dual system on my truck, though with stock manifold, and dual cats. I live in Phoenix-so I would think I could get some perf.-but I think you may be right about the TB spacer.

I also eliminated that resonator on the air intake, and noticed a change with that. I am uncertain about the MAF-does that really provide a substantial change? As I believe they are relatively pricey.

Skyz71 Enthusiast

Skyz71

Posted
Posted
Well, I found a 75mm TB on ebay for about $100-so thats what sparked my interest-i'll look into that unit also. Right now I have a full dual system on my truck, though with stock manifold, and dual cats. I live in Phoenix-so I would think I could get some perf.-but I think you may be right about the TB spacer.

I also eliminated that resonator on the air intake, and noticed a change with that. I am uncertain about the MAF-does that really provide a substantial change? As I believe they are relatively pricey.

 

 

 

 

The thing with the MAF sensor is that it is de-screened, as in it's the sensor elements and thats it, everything else is free flow. The stock unit has a honeycomb type screen that is actually pretty restrictive from what i've noticed, but your right, they are pricy and not necessairily worth the money for the benifit you'd get from it. Where did you find that 75mm tb, who makes it, cause thats sparked my interest as well. And about your exhaust, im being told that the stock manifold is sufficiant, all headers really do for the truck is give it a meaner, throatier sound. But your def right, the MAF sensor probably isn't worth the money especially if you plan on doing what you said you were. But yeah, i'd be very interested in finding out about that 75mm tb. Thanks!! :bs:

 

Jeff(skyz71)

zippy Enthusiast

zippy

Posted
Posted

You're a long way from needing to descreen the maf. There is little to no restriction in running the screen. Your biggest gains would be in programming, higher stall speed converter, and a cam/valve spring swap. The stock ignition was more than enough for the truck. If you were to run the truck on the dyno you'd find that you gained very little if anything at all by putting the MSD box on. Replacing the stock throttle body may gain you a few hp, but here again it's not much of a restriction for you at this point. Installing a throttle body spacer is worth barely more than the box that it comes in. A bunch of mods because they are cheap aren't usually worth the cost you paid for shipping. You could gain more in tuning the pcm than you've already gained in all of your mods so far. I don't recomend milling the heads or changing the valve size. Your idea of putting in bigger valves, adding a bigger throttle body, and changing/modifying the maf are all old school idea's that just aren't what's needed for your truck at this point. You need for them to be a restriction before it's helpfull. Change the torque converter, cam and valve springs, and get it tuned. Those mods alone will be worth a full second in quarter mile times if you do it right over what you have right now.

Levman74 Enthusiast

Levman74

Posted
  • Author
Posted

Well, I knew that de-screening the MAF wouldnt help, as it's purpose is for a more accurate reading, and a new convertor wouldn't help me, as I have a manual tranny. But I'm interested in this tuning part-how would i go about doing that? Does that involve one of those hypertech deals? Involving the MSD box, I did notice a change in throttle response with that, as well as a smoother idle, not to mention a 2 mpg gain overall-so that was good for me. My main purpose for this whole endeavor is to increase output power for towing and hauling missions. Thanks for the info regarding the TB mods tho.

zippy Enthusiast

zippy

Posted
Posted

For pcm tuning I'd recomend you either buy tunercat tuning software or get a mail order pcm from someone like ed wright.

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