tux2112

232/240 593/603 112 ... think the 987s will be up to the task?

Hugger SS

..I had a 595/595 230/230 on a 110 had no problems with valve float

CamM

3500 miles with 987s and I'm down 20rwhp. Jay at Absolute Speed thinks it could be my springs already. I would go with another spring with that lift.

verbs

Don't even think about it!! Those springs are good to .580 and that's it. I have them and get bad valve float with my YT rockers and 230.8/224.3 .576/.563 110.8LSA

My springs were fine when I had stock rockers on ,but the YT's were just enought ot push em over the edge. 987's are older technology. Do it right and get a set of Comp 921's or Crane dual springs that are good to .650 lift.

tux2112

edited

Black02SS

iTrader: (36)

I am currently running the 987's and I think I am going to switch out to the crane duals. I just dont' want to take any chances.

Damian

iTrader: (89)

I am getting valve float w/ 987's and I am not running anywhere near the lift of that cam...

josh

Country Boy

iTrader: (24)

Dont do it. I had the G5X2 cam which is very similar to the one you have and Jay @ Absolute had to replace my valve seats from valve float with only ~2500 miles on them.

tux2112

Any suggestions on other springs? Since my heads have been machined for the 987 springs I can't use the 921s or other "stock" size springs...

so ... any other springs that would be good for big lift that are direct fit replacements for my 987s?

Country Boy

iTrader: (24)

Comp 977s, but youll need the Comp "R" lifters because the spring pressures will collapse a stock lifter.

tux2112

ok cool I'll look into getting some 977s .. I already have Comp R Lifters so should be good there

SPANKY LS1

iTrader: (24)

I *think* you can still run a sock diameter spring with the spring pockets cut. I think that the 921s, REV 1116s, etc are located by the inside of the spring, not the outside. I may be wrong, it wouldn't be the first time, but I think that you'll be ok. Might wanna call Brian at TEA, Terry at Patriot or Jay at AS and see what they say.

Shawn

tux2112

I checked w/Speed (they're building the motor) and sounded like you can't use the smaller springs once the heads have been machined for larger... also talked to comp cams and they said the same thing (though the dillweed that answered the phone was an asswipe and not at all helpful....)

are there any other springs on a 1.430 OD that can handle this much lift/duration safely or are 977s the only way to go? (1.460 OD )

Nickn20

Don't waste your time with REV duals, they are garbage, have a friend that already broke one of thier new springs!

broke 4 of thier old ones.

Cliff

iTrader: (19)

I have 987's and no problems. The lift is suppose to be good up to 600 lift. I have a high lift and duration cam.

94form2000z

iTrader: (10)

I am running the 987 with a 588 lift cam with no valve float. I know I am on the very edge of what they'll handle though. Stock Rockers here.