but that is just it. I talked to Hughes and they said it is for the stock magnum 5.2 or the 5.9 but a tunner is used as it does not play well with the stock pcm.

they also said they have not used the magnum whiplash cams in any pre-magnum roller cam 5.2/318 tbi engines or carbed LA engine.

they would also NOT recommend me using the comp 901-16 springs and was not sure if the hughes LA spring would work with the heavy roller lifters.

there is a member here on the board that has his DAK 5.9 set up with the whiplash roller cam and is bad azz for a stock 5.9
also vids on a dyno with over 400 hp IIRC

I was running a lunati voodoo roller cam for the magnum engine, I looked up a single spring with the same specs as the lunati double springs. = comp 901-16 save $ on machine work/retainers/seals 901s are single with damper/a drop on replacment with out R&R the head/use stock seals/retainers

I was happy with it but stock smooth idle I was not happy with...I was expecting more of an aggressive idle from the hype on the voodoo

looked at the hughes whiplash magnum roller cams and noticed it was almost exact specs as the voodoo roller.

talked to hughes and they would not coment on the voodoo and whiplash being close/copys with some spec changes for the lumpy idle.

so I rolled the dice with the 5.2 whiplash roller, used comp 901 springs. stock roller valve gear in a JY 91 318.

works like a champ. pulls right to 5500 rpm, no valve float, woke the 318 right up for traffic in a daily driver truck.

mind you I have had it in 3 different pre-mag roller cam 318s now 5 yrs time. all do to very high mileage on the used JY engines.

that's why I feel comfortable rolling the dice on the 5.9 whiplash in my pre-mag roller cam 360 headed 318.

magnum 5.2/5.9 use the same head and have the same 9.0 to 1 comp ratio
85-91 pre-mag roller cam 318/360 have the same 9.0 to 1 comp ratio

so any more than that I would agree it wont work well. as per hughes as well.

call them up and tell them what you want to do with your combo and get a recommendation from them.