1racerdude

If ya have enough spring then there is NO way the lifters will pump up.....
The only way a lifter CAN pump up is from slack in the valve train-- caused by valve bounce floating or launching which is caused by not enough spring.
The 1/8 turn keeps the lifter from pumping up AS FAR as 1 turn hence it will not hold the valve open as far or as long until it backs down. There is over .100 in the lifter body for adjustment.
I am sure Bret furnished enough spring with that set up but if ya don't have at least 130/350 AFTER break in then it's not enough.Springs will loose 15-25lbs after a few heat cycles.
Surge at cruise isn't caused by valves usually unless ya got some holding open from adj or something else. Surge is caused by tune as has already been mentioned. This includes plug gap,wires,sensors,fuel delivery,timing,etc. Ya may not get it all out at certain RPM's but it shouldn't ****** the drive shaft.

SStrokerAce

Oh yeah Larry, LOT more spring than that.

Bret

1racerdude

I figured so.

brokeTA

Well the main problem was the weak coil. It was used and must have starting goin out on his way home. Put a new one on and it ran just fine (well as good as it did before). Re-adjusted valves, and that made virtually no difference in anything. We put the factory 24 lb injectors back in and now the car runs extremely smooth all the way through. So either the injectors are just way to big (pulled up to 25% fuel in some areas) or there was one/couple of them sticking open. So now we will re-tune and see if the DC on the 24s work out ok or if we will need 30's. On motor I don't think it will need more than 30's. Main restriction is the stock intake and stock tb.

1racerdude

If the injectors are OK they can be tuned to work just like 24#,but give ya the fuel ya need with stock fuel pressure.
MadWolf or PCMForless can do it or Ed Wright.

Sweetred95ta

I think you're going to be pushing it with the stock injectors, but Tim should be able to make it work for now. Does he have an adjustable fuel pressure regulator? He could run a higher fuel pressure to help. I think I calculated the stock injectors to be a 33.1 lb injector at 60 psi.

1racerdude

Got PUMP?

mad scientist

That is extremely contradictory. If tuning doesn't eliminate surging, then it's not caused by the calibration. Certainly, the wrong tune could induce surging. BUT if you find yourself tuning around a surge, there is something else going on. Of course this is off topic because surging was not an issue in this thread. Just wanted to be clear that tuning is not the only reason surging CAN be an issue w/ some combos....

mad scientist

No need to do that. I have tuned big injectors before (and replace their work all the time).

... I think there might be one or two bad injectors...

1racerdude

It IS NOT contradictory at all. A BAD TUNE will magnify a surge.
Ya CANNOT TUNE OUT A CAM LOPE due to overlap. If it bucks ya got to run it at an RPM where it doesn't buck.
Not my first rodeo.

1racerdude

If the injectors are OK they can be tuned to work just like 24#,but give ya the fuel ya need with stock fuel pressure.
MadWolf or PCMForless can do it or Ed Wright.



When ya get the reputation these three tuners have ya will be somewhere.

mad scientist

....maybe I'm just reading too much into what you posted. If so, then I'm sorry. Just trying to understand your point.

mad scientist

I'm working hard on that, tuning is my full time job. It's my passion.

HardcoreRM125

Hahah believe me, him, bret, and LE are not the ones you want to argue with. They have been in the feild longer than you have ...

Im sure you are great at what you do, so dont take offense. And you'll learn that 1racerdude types stuff alot of times in a hurry to make a should-be-known point, well, known. He is right, a cam is what makes the surge. There is nothign you can do with some cam designs. The tune can make the surge significantly worse, or significantly better, even gone depending on the situation. BUT, some cams will do that regardless of tune.

mad scientist

Yeah, I only have about 8 years in it...