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Discussion Starter #1
1992 with 47RH and four disc converter, stock hp is 160, would a 3200 gov.spring and slight pump tweek get me around 220HP. all im looking to do is get the same performance as a late 2cd gen, early 3rd...
how much difference does a 16cm exhaust housing make..presently have a 18.5
its really easy to say " my engine makes 350 hp" as alot of people do.. but i want simple, dino tested results, so if someone has tweeked their pump and done simple mods and has REAL figures and results i would love to hear from them.
eric
 

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Unless you can find a 16cm housing real cheap. Don't buy one new. The amount of inprovement it makes isn't worth the cost.

Just some mild pump tuning can get you into the 220 HP range. Much more and your going to need bigger exhaust, injectors.

You have a 47Rh in the truck. That helps a lot with the lockup converter.
 

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Discussion Starter #3
i bought a 4" downpipe today and went to my favorite local semi truck yard and picked up a nice 4" muffler and several elbows and bends to make the rest of the system so i should have a nice quiet free flowing 4" exhaust. a new 16cm housing is only $ 175 is there a better " bang for the buck " if im going to spend that amount... wont it help keep the exhaust temp down as well...
eric
 

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Going from a 18.5 housing to a 16cm isn't worth the money. Your paying $175 for 2 PSI more boost. A 1/2 turn on the fuel screw will give you more boost than that.

The smaller housing will raise the EGT's temps a small amount. On my truck when I installed a 16cm on the H1C. I noticed a 50 degree raise in EGT's over the 18.5 housing. The difference in spoolup was very small.

A governor spring doesn't add HP. It raise engine operating RPM and fueling for the higher RPM.

I would use the money from the exhaust housing and get a set of cooltubz's or a 2nd gen 24 valve air horn. Your stock air horn is restrictive.
 

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Discussion Starter #5
i am confused, if adding a 3200rpm gov spring prevents " defueling " and lets the engine still produce power at a higher rpm, wouldnt it also, within reason make a bit more hp...
and wouldnt a smaller turbo housing which would create more air flow keep the engine temp down a bit... im willing to be educated on that one, but telling me that a higher gov. spring doesnt increase hp doesnt make sense.... more fuel + more rpm + more boost = hp...
 

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i am confused, if adding a 3200rpm gov spring prevents " defueling " and lets the engine still produce power at a higher rpm, wouldnt it also, within reason make a bit more hp...

and wouldnt a smaller turbo housing which would create more air flow keep the engine temp down a bit... im willing to be educated on that one, but telling me that a higher gov. spring doesnt increase hp doesnt make sense.... more fuel + more rpm + more boost = hp...
The 3200 GSK could help you make more power provided you can maintain the torque level at those rpm. Most engines will experiance a drop torque. Until they get a bigger turbo to provide more air.

Here again a smaller turbo housing will spool faster and the turbo will hit peak flow at a lower rpm. It should be more fun to drive with a smaller housing. But due to the reduced air flow you will make less HP.
 

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Sorry I haven't been back to answer your questions. I have been busy doing a G56 swap into my truck.


i am confused, if adding a 3200rpm gov spring prevents " defueling " and lets the engine still produce power at a higher rpm, wouldnt it also, within reason make a bit more hp...
It might make a little more HP. The issue is your old valve springs. Every 1st gen I have been in with the 3200 spring. The RPM range above the stock settings isn't very usable. Most of those owners still have the stock valve springs. You can tell when the engine hits the old governor setting RPM. When trying to go above the old setting you can feel the engine start slowing down on its acceleration curve. If your towing you can realy feel the slow down.

Replace the valve springs if you do a governor spring. Make the extra RPM usable.
 

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Sorry I haven't been back to answer your questions. I have been busy doing a G56 swap into my truck.




It might make a little more HP. The issue is your old valve springs. Every 1st gen I have been in with the 3200 spring. The RPM range above the stock settings isn't very usable. Most of those owners still have the stock valve springs. You can tell when the engine hits the old governor setting RPM. When trying to go above the old setting you can feel the engine start slowing down on its acceleration curve. If your towing you can realy feel the slow down.

Replace the valve springs if you do a governor spring. Make the extra RPM usable.
So i been trying to learn more bout these mechanical 12v so i dont mean to step on anyones toes so please teach me...i read that these trucks dont experience valve float till 3400rpm wit stock springs and 3800rpm wit 60lb er's? So i guess wat im trying to say is besides a 3200 spring wat will allow me to turn 3400 rpm or more? Sorry if this dont make since
 

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Trying to turn above 3200 is about a wasted attempt on a VE. The VE doesn't fuel will at high RPM's. The design of the pump has built in restrictions that can't be removed. Those restriction do not allow high RPM fueling like a p-pump does.

With a VE engine you have to make all your power down in the 3200 or less RPM range.

As far as valve float. Yea that normaly happens above 3200 RPM or so.

But weak valve springs do not let an engine Rev as freely/ fast as it should.
 

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Ok that clears things up man
 
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