hmm, yeah good point.

 

Thats what I was trying to say as well. If you are going to pull the heads to change the springs... you mise well just throw the cam in. With the non-adj 1.6's you'd be good to go without a problem. But do what you need to do.

---- EDIT
Straight from Harland Sharp's website

*There a few things to consider before upgrading to the 1.7:1 rockers. The higher ratio is going to add about .030 more lift. On a high mileage car this may rapid fatigue of the valve springs. If you have more than 50K miles we recommend getting a new set of valvesprings.


- - -

There was also talk of using hardened pushrods because of stock rod deflection around 5000 something rpm. The Harland Sharp RR dont use guide plates. Just something else to think about.

 

i donnt think my truck has ever seen 5000 rpms.i donnt really run my truck very hard.once in awhile i might floor it.(just to show them chevy's that my stickers on the windows arent just for looks).lol

i read that on the harland sight about the 50k thing. i am thinking that they are just trying to be cautious,to cover there butt.i have 57k on my truck so i think that i would be o.k.

silver...where did you see your gains at? low end,top end? and what was your mileage when you installed them? is your truck a daily driver?

 

Gains are most noticable at low and mid rpm. Truck really pulls harder all the way through mid rpm. Seemed to rev quicker too. They are supposed to be good for 20hp.

I can't remember my exact mileage, but it was around 75k (I installed them 2 years and 3 months ago). I now have 92k. Truck is a daily driver except for this summer when I bought a gas sipper and have driven it for the last couple of months.

I talked to John Mercedes about the valve springs and pushrods when I installed mine, and he said they were not necessary unless I was going to be racing or running at high rpms, or was running a head/cam swap (in which case I would have stayed with the 1.6's). He told me he designed the rockers to work with all factory equipment. New springs and pushrods are a good mod, but not a necessary mod. It's true that the stock pushrods are thin grade metal and tend to flex, giving you deflection. This causes less cam lift and lost power. But this would only be noticable under heavy loads/high rpm use.

I may still upgrade to hardened pushrods someday (and HD springs if I think it is necessary), but for now (given how long i've had these installed), I see no immediate reason to do so.

 

thanks silver. i think i am going to give them a try.i thought i had seen in another post you said low to mid.just wanted to make sure.

i am going to go ahead and make the purchase here in the next couple weeks.i talked to the guy at my local shop and he said he would change them out for me for 100$. does that sound resonable?sounds pretty cheap to me.(he did my front brakes and rotors for 20$)

everyone keep chiming in.

 

are u getting adj or non-adj ? If non-adj, i'd do it myself without a doubt.

 

Ya, it is not difficult at all. Save the $100 for some other mod.

 

talon6- I agree with Silver. The Harland Sharp 1.7's are definitely worth it. I've had mine for more than a year and a half and they are working just fine. I had approximately 65,000 miles on my truck when I had it installed and I used my stock valve springs and push rods. I bought this mod to help with my towing performance and it has definitely delivered with extra performance and power in the low to mid range. I would also get the headers next to allow your truck to breathe better and to compliment your existing exhaust mods. I would then get the SCT tuner to tie everything together and to bring the most performance of your current mods. I know the SCT tuner is pretty pricey but worth the price. I love mine and it blows away Hypertech and Superchips from my own experience with both programmers. Hope this helps.

 

Sorry I'm so late to the thread.

Yes I run 1.7's,

Yes they are worth it, and

Yes you should buy them from John Mercedes and no one else. Well, except the fine folks that sponsor us of course (cha-ching!).

No, you do not have to replace the valve springs or pushrods. The pushrods should be good to 5500 RPMS and the rev limiter kicks in at 5250 (though I wouldn't be pushing it like that too often). The stock valve springs are supposed to be good to .500 lift, IIRC. The stock lift of the Ram's cam is .432. The 1.7's raise that to .459, which should still be well within acceptable specs.

This is a mod that the butt dyno will actually "feel." The more flow you have in and out of the combustion chamber, the more benefit you should see. For instance this is Hughessengines.com cylinder head chart. According to this chart, you would probably see even more benefit from running the 1.7's with their "Iron Ram" heads than you would with the stock heads. Note how the stock heads don't gain much from .400 to .500 valve lift. The heads have "maxed out" and are probably a bit of a restriction (assuming that there aren't restrictions in other portions of the system). Now, if you go to the Iron Ram 2.02's you see MUCH more flow, but you better be able to support that flow or it ain't going to mean a thing. Larger injectors might be in order as well as an M1 and nice open exhaust.

 

Good info!