87 V10 5.7 Runnin rough

[Bain1012]

Wasn't tryin to sound like an arrogant ***** in that ^^^ message

 

[CSFJ]

Wasn't tryin to sound like an arrogant ***** in that ^^^ message

Never took it that way. I'm no expert at engine porting, just going on how it was explained to me a long time ago. The way I heard made sense to me back then, but I have no dyno numbers or even the dis-assembly of a long term engine that it had been done on to compare to.

 

[HotRodPC]

Wasn't tryin to sound like an arrogant ***** in that ^^^ message

Why not? The rest of us do !!! Actually not really. Pricks aren't allowed here, they get run off to Pirate4x4 pretty quick.
I didn't take it that way. I took as you saying you've done it before and it hasn't caused this kind of problem in the past.

 

[HotRodPC]

But, I have heard close to what CFSJ is saying though. Not about the porting though but about the polishing, that it's best to leave the port porous instead of smooth and shiney. But, how do you really open up a port and leave it porous? Whether you polish it or not, you've still made the port smooth by grinding it out.

 

[CSFJ]

But, I have heard close to what CFSJ is saying though. Not about the porting though but about the polishing, that it's best to leave the port porous instead of smooth and shiney. But, how do you really open up a port and leave it porous? Whether you polish it or not, you've still made the port smooth by grinding it out.

Depends on how course of grinding stone you use, or the grit of the piece of sanding belt you use for a flap wheel on the final passes.

 

[CSFJ]

The way it was explained to me is that if the walls were too smooth and polished, the fuel charge would be more apt to puddle on the sides instead of atomize properly. So instead of going for a real fine grit on the last pass, leave it a little rough.

 

[PrairieDrifter]

That's how I was told also and it makes sense to me, the roughness causes slight "swirling" if you want to call it that, in the intake port on the head an when you polish it takes that away and the fuel separates from the air because that roughness is gone and it doesn't have that "swirling" for a good air fuel mixture. And I don't have any dyno numbers or anything like that either, but it does make a lot of sense to me.

 

[Bain1012]

Well gonna be a bit longer before I figure this out my tcase pump just rubbed through the case and dropped all my fluid on the highway.

 

[PrairieDrifter]

That sucks!

 

[Bain1012]

Just need a limper till novemberish. It's gettin a NV4500 and a np205.

 

[CSFJ]

Just need a limper till novemberish. It's gettin a NV4500 and a np205.

Lol. Go big or go home.

 

[Bain1012]

Can't go big when the pocket can't afford it.

 

[CSFJ]

I meant the nv4500. I consider that a pretty big upgrade. More than I want to spend any ways. That's why mine is getting the old m465. I can still find those a lot cheaper than the 4500

 

[HotRodPC]

NV4500 and NP205 is a very doable upgrade. Affordable too considering the upgrade to NP205 and getting the overdrive, considering you can get both upgrades, overdrive trans and NP205 gear driven Tcase for cheaper than adding a Gear Vendor overdrive unit.

 

[Jims86]

I can't remember but I thought it wasn't a very good idea to polish the intake ports on the heads for a tbi? The rough surface is better for the air and fuel to mix giving you a good mixture and if you polish it takes away that roughness and the gas tends to separate from the air. I think it was for tbi cuz port injection doesn't matter because the fuel is sprayed right on the intake valve and it doesn't have to mix in the intake manifold itself.
Just brainstorming!

This is especially true now, since the Vortech intake manifold does not have an exhaust crossover to heat up the air fuel mixture when it enters the manifold.
Hot Rod, the vortec has a higher flow rate than the TBI heads, and more volume, wich throws everything outta whack with the stock TBI tune...i dont know if you remember, but gresdog has a similar setup tha runs like dog **** untill about 2000 rpm. Each setup will be different, due to the different calibrations that people are using. As far as switching to the 2" bore t-body...I wouls ask Westers what they recommend. I personally would baseline tune for stock equipment to get it running it's best, then do all the power mods down the line.