Thinking about buying some 5k gov springs. What are the good ones these days ?

Yeah, Haisley 5k's, with their valve spring kit (the $550 one) is a really nice combo for daily driving, reliable stuff that's still really fun.

I have mine loose so I have a really strong idle (to the point I can get it stable low enough to starve the oil pump, so don't do that). It probably maxes around 4300rpm (being so loose) but I'm way out of air by then anyways, so who cares. Daily drives awesome, revs super fast, very OEM+ feel.
 
Would the Haisleys be worth the upgrade from 4k’s on a 160 pump street truck? Curious if there would be anything to gain. Don’t see the truck ever going much passed 3200rpm with the 160 pump.
 
bateman said:
Would the Haisleys be worth the upgrade from 4k’s on a 160 pump street truck? Curious if there would be anything to gain. Don’t see the truck ever going much passed 3200rpm with the 160 pump.
Click to expand...

Yes. And you can just remove one spring to make the 5k into the 4k I believe.
But if you take a 4k set and put it on loose like I was mentioning before, it'll idle strong but it'll defuel pretty early. That's what I originally started with, then moved up to 5k's.

Spend the money now and you'll be happy you did.
 
I have 60lb springs, hardened keepers and retainers. Putting a 72/87/1.0 on my 95’ soon. Picked up a used fass 260. Hopefully the truck runs a lot harder than it did on 5x16s , 71/76/.9 and a factory lift pump with stiffer spring. With my old setup I could out run my coworkers bama tuned 5.0 with a couple bolt ons. Hoping to be a bit faster with the 72, 18s , fass.
 
SCHMITTY said:
I have 60lb springs, hardened keepers and retainers. Putting a 72/87/1.0 on my 95’ soon. Picked up a used fass 260. Hopefully the truck runs a lot harder than it did on 5x16s , 71/76/.9 and a factory lift pump with stiffer spring.
Click to expand...

That's a huge fuel pump for your truck. And I don't remember what 60lbs springs are good for rpm/intake pressure wise. I didn't think it was much past 3000rpm/~40psi.


SCHMITTY said:
With my old setup I could out run my coworkers bama tuned 5.0 with a couple bolt ons.
Click to expand...

Tell him to stop being lame and toss a turbo on that 5.0L. Those things are made for it! They'll run 8's for around $8000 into fuel, air, trans, and tires.
 
Yes the Haisley 5K springs, a thousand times over! Ive seen 6,000 RPM as I'm letting the clutch out on the line hooked to the sled. And thats in a 180 500cc pump with the Haisley springs.
 
Remember it's not gonna make much power over 3500 rpm's no matter what gov springs you run, unless your running over 30° of timing.

Yeah it will free rev up there with no load, but won't make any power up there. With that large 72mm single, your gonna have to turn it up there to work the charger hard.
 
jasonc said:
Remember it's not gonna make much power over 3500 rpm's no matter what gov springs you run, unless your running over 30° of timing.

Yeah it will free rev up there with no load, but won't make any power up there. With that large 72mm single, your gonna have to turn it up there to work the charger hard.
Click to expand...

I second this. I run a 72/87 .9 T4 on my manifold and its not doing much of anything below 3000rpm. The party really starts 3500+ rpm even with the tighter housing. I couldn't get the 1.0 housing to spool in under 15 seconds even with a very loose converter (400rpm over stock stall). Not much good if you actually want to line up and race somebody.
 
I have a stock stall triple. The builder said he’d re stall it for the cost of a cut/clean job. Maybe a v10 stator in my future. The k31 based 71mm started making boost by 2300 and pulled hard to 3200+ depending on when I ran out of fuel pressure. I have a nitrous setup with a 4an from the bottle to cheater solenoid and from there it’s a 3an line to the nozzle.
 
CorneliusRox said:
That's a huge fuel pump for your truck. And I don't remember what 60lbs springs are good for rpm/intake pressure wise. I didn't think it was much past 3000rpm/~40psi.




Tell him to stop being lame and toss a turbo on that 5.0L. Those things are made for it! They'll run 8's for around $8000 into fuel, air, trans, and tires.
Click to expand...

I’ll tell him. He’s a delivery driver for a local trucking company. I unload the trucks at whatever job site I’m on so we talk a little trash and every so often we end up in traffic together at quitting time. Both of us live out of town a ways and the roads are long and straight.
 
Vincejax said:
I second this. I run a 72/87 .9 T4 on my manifold and its not doing much of anything below 3000rpm. The party really starts 3500+ rpm even with the tighter housing. I couldn't get the 1.0 housing to spool in under 15 seconds even with a very loose converter (400rpm over stock stall). Not much good if you actually want to line up and race somebody.
Click to expand...

How much fueling do you have ?
 
You must log in or register to reply here.
Back
Top