420 HP cam specs??
#1
Thread Starter
Gold Member

Joined: Oct 2005
Posts: 11,688
Likes: 216
From: Olmsted Falls,Ohio Marblehead,Oh
I was looking to find out what the cam specs are on 420's, are there any worth while cams availible for it to make more power and not go roller?
what is a HP500 cam speced at?
what is a HP500 cam speced at?
#2
245 Limited,
420 Flat Tappet Hydraulic
298*/306/ @ .005"
228*/236* @ .050"
.312"/.324" Lobe Lift
.530"/.551" Lift Valve
114* +5*
HP 500 Hydraulic Roller
284*/292* @ .004"
222*/230* @ .050"
.339"/.352" Lobe Lift
.576"/.598" Lift valve
110* +5*
Bob
420 Flat Tappet Hydraulic
298*/306/ @ .005"
228*/236* @ .050"
.312"/.324" Lobe Lift
.530"/.551" Lift Valve
114* +5*
HP 500 Hydraulic Roller
284*/292* @ .004"
222*/230* @ .050"
.339"/.352" Lobe Lift
.576"/.598" Lift valve
110* +5*
Bob
#4
The 420 cam is a flat tappet. Crane #132561.
The 500hp cams are roller cams.
You might be able to gain a little with a custom grind in a flat tappet, but probably not enough gain to make the change worth it.
The 500hp cams are roller cams.
You might be able to gain a little with a custom grind in a flat tappet, but probably not enough gain to make the change worth it.
#5
Thread Starter
Gold Member

Joined: Oct 2005
Posts: 11,688
Likes: 216
From: Olmsted Falls,Ohio Marblehead,Oh
I knew the 500 was a roller, I was wondering if I could get close to the specs with a flat tappet, I will just keep what I have for now, I will do a roller conversion later maybe, then change cams.
#6
The design is totally different on flat tappets and rollers. Rollers have much steeper ramps on the lobes. You can't do that on flat tappets because of the way the lifters slide on the lobes. Thus on flat tappets, when you increase lift significantly, the duration goes up as well.





