mhuppertz

I want to take my engine to the next power level (bearing in mind I have to do things a little at a time). What would be the next best step for me in your opinion?
Thanks,
Mark

BC847

How fast do you want to go, or should I say, how quick do you want to get there?

mhuppertz

Right now my truck will go about 120MPH, and it seems like it will wrap forever, but I want more horsies. I only have about 400 at the crank.

BC847

- Take that 3200 governor spring and cut out about 4 loops. BE SURE to stretch the spring back to its original length.
- Run the fuel screw all the way in.
- Re-index the throttle-shaft loose so that when you attempt to start the engine, it won't idle. Now advance the throttle index in single notch increments till the idle is maintained. BE PREPARED FOR RUNAWAY!!
- Back the high-limit screw out till there's about an eight of an inch showing.
- Adjust all the linkage such that looking at the pedal has the engine rpms rise.
- Advance the timing including jumping a tooth or two till it clatters pretty good at full load.

You may have to toy with the idle afterward by re-indexing the throttle shaft and/or adjusting the tie-rod that connects the throttle stuff.

BE SURE to test the engine for idle with each small adjustment of the indexing and have a wire connected to the kill lever should it be needed during tuning.


Little stuff.

JQmile

Bigger turbo and bigger injectors. I'd go with some 70 lpm dynomite diesel injectors (you have to ask for them) and a Super HX40 or S300 turbo. Probably looking at another couple grand, minus whatever you can sell your old stuff for. Injectors and turbos are also really easy to swap out. Haven't been to the dyno yet, but I went from a HTT 60mm upgrade to a 62/65 with a 4-inch downpipe, and the truck def. feels much stronger. Spun from a 3rd gear roll yesterday

You could also do water/meth--should give ya about 50 hp

mhuppertz

Did all of this before except te spring cut. I will try that the next time it gets above freezing here. Thanks for the tips!

Crossy's son

Bigger injectors

Bigger turbo

mhuppertz

I have a water/meth unit to put on, just need another nozzle. My HTT Stage IV seems to be flowing more than enough air for my 370 POD's because the exhaust cleans up at higher speed. I was thinking I needed more fuel next, like a 14mm head or something.

mhuppertz

Although at 110+ MPH my Exhaust temps are nuclear.

JQmile

I'd still take a look into bigger injectors. 400 hp at the crank is like 300 at the wheels, and there are a few people out there who have made 450-500 at the wheels with 12mm heads, so you still have a bit of room.

big stinky

What does clipping the spring do? What would happen if you didnt stretch it?

Crossy's son

It makes it "weaker". more RPM's

BC847

- The goal of clipping the 3200rpm spring is to get a higher engine rpm. You end up with a stiffer spring and therefore higher fueling than otherwise (though the rate of return diminishes in the case of the VE IP).
- If you don't stretch the spring back to its original length, when installed, the internal throttle lever isn't parallel to the associated governor mechanism linkage (the spring connects the two). As such, there isn't a 1 to 1 ratio of movement with the end result being: a bunch of initial throttle movement equals a little fuel.

big stinky

Thank ya! Is valve springs a good idea with this mod or does it keep the revs in the safe zone for stock valve springs?

BC847

With a stock/OEM valve-train it's my understanding valve-float potentially becomes a problem above perhaps 3500rpm. There's a number of variables as to how high your mess might rev: WOT under a load, WOT in neutral, boost pressure pushing against the intake valves, etc.