i dont know if many of you have tried to put a camshaft in your 4.2/4.0

but if you have you've probably noticed that you have to have the head machined for the provided valve springs to work.

and in some cases...the springs they send absolutely WONT work. (coil bind before max lift is achieved)

so i've been searching for months on end for a set of valve springs that would give me everything i needed without any machine work

the answer was in Australia!

Performance Springs (.com.au)

The part number is 5003.

--107.5 seat pressure at 1.625 installed height

--1.340 O.D./.990 I.D.

--Coil Bind= .970

This spring is perfect for I.D. and it bumps up the seat pressure from 70ish to 107 for performance cams

and the low coil bind allows for lift of upto .655 at the valve!!!!

since 4.0's have a 1.7 rocker arm ratio this provides quite a problem because most cams are sent with specs for 1.5 and 1.6 ratios.

the cam i have will give me .544 lift at the valve and i can install these springs and i wont have to mill the spring seats or buy different retainers.

and the best part?

these springs, shipping included, are cheaper than any comp or crane springs that i have found.

Actually finding someone that would send them to me was quite a chore but after emailing about 10 Different vendors someone directed me to

allenw@performancesprings.com.au

he accepts pay pal and is a great guy to deal with.

MOD AWAY!!!