Stock steel or Roller rockers?

willys1

Active Member
Dec 2, 2003
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New Jersey
Need some advice,,Im getting Thumper heads,but keeping the stock cam.Would the factory steel stamped rockers arms be OK,since I dont see revvivg alot higher,,,or should I get roller rockers? Keep in mind I drive 40,000 miles ayear !!
 
dude, do the research first and look up some real world dyno numbers. roller rockers are worth HP even at the same lift ratio cuz you are losing a lot of friction (i.e. your engine is more efficient and will get better gas mileage). besides the stock ones are pretty worthless, not to mention innacurate and USED. If you are going to go with stockers at least get some new ones. but rollers are well worth a couple hundred dollars more especially if you use 1.7's to get a little extra lift with the bigger ports and valves.
 
vikingpower said:
dude, do the research first and look up some real world dyno numbers. roller rockers are worth HP even at the same lift ratio cuz you are losing a lot of friction (i.e. your engine is more efficient and will get better gas mileage). QUOTE]

I wasn't disputing the fact that they are worth HP; just not worth a lot on a stock-headed, mild combo that doesn't get reved too high. Show me some dyno graphs of a stock headed engine that show a really good gain from just roller rockers if you have them, because I'm actually curious.
 
vikingpower - there's not just one answer here. I've seen dyno tests where there was no gain whatsoever on a mild H/C/I combo on a 302. I've seen dynos where a mild carbed combo put out 23 more HP with 1.7's.

You have to look at the specific combo and even then it's hard to tell what's gonna happen with the roller rocker installation. I think it's more likely that the gains you're gonna have are likely to come from the lift increase due to bigger ratio, and a stiffer rocker body (compared to stock) that doesn't flex causing a minor loss of lift than any measurable gains due to friction reduction.

Willys - stock stamped rockers should be fine; if you wanted to upgrade a little, CompCams makes a stock replacement rocker (not a roller) that's supposed to be quite a bit stiffer than the Ford piece.
 
Thanks guys :nice: Actually I know R.R.'s are only worth about 5HP on this application. I am interested in R.R's,but I need the durability of the factory ones(stamped steel) because I put a ton of mileage on a car.The rollers have needle bearings dont they? Do you think they would last as long as regular steel ones? Thanks Mike,,I will definitly look into those rockers.But what do you think about the life span of R.R.'s. .
 
If your going to get a set, get a set of 1.7's if you want to see a real gain. Stockers are 1.6, which are not as accurate durring manufacturing so you probally have between 1.55-1.65's and they might not be as strong but with the stock cam and valvesprings I don't think this is an issue. Put the money in to the double valvespring upgrade. I would get the double valve springs with the thumper heads, I did and it has no valve float at all, used to get it around 5800 with stock springs, but every case is different.

Oh, and you say you don't do much revving, well when you put the heads on that might change. :p
 
90mustangGT said:
If your going to get a set, get a set of 1.7's if you want to see a real gain. Stockers are 1.6, which are not as accurate durring manufacturing so you probally have between 1.55-1.65's and they might not be as strong but with the stock cam and valvesprings I don't think this is an issue. Put the money in to the double valvespring upgrade. I would get the double valve springs with the thumper heads, I did and it has no valve float at all, used to get it around 5800 with stock springs, but every case is different.

Oh, and you say you don't do much revving, well when you put the heads on that might change. :p
Well with my T.C. is revs alot more now.But at the track I dont take it past 5000rpm much because theres no power up there.
 
Just use the proper procedure for installing them - get a shim kit; if you buy new, they'll come from Crane with a shim kit. Install them properly, if they're noisy, let it run til warm, then re-install with everything hot.

Break in? Yeah - by the time you get to the end of the driveway, they're broken in. ;)
 
Michael Yount said:
Just use the proper procedure for installing them - get a shim kit; if you buy new, they'll come from Crane with a shim kit. Install them properly, if they're noisy, let it run til warm, then re-install with everything hot.

Break in? Yeah - by the time you get to the end of the driveway, they're broken in. ;)
Actually Im getting them installed by a shop Mike.(At the same time as my Thumpers)So I take it I can test them on the ride home :nice:
 
dyno stuff

a good place start looking at some dyno data is (if I can remember the title exactly, I dont have it on me) "5.0 mustang dyno tests" or something, by Cartech, at Barnes and Noble, but you should be able to get one pretty easily. I got two of them actually cuz I lost the first one. Theres also another one called the official 5.0 mustang performance guide or manual, also got that one at barnes and noble I think, but it goes into really good detail about stuff like this. It even says using roller lifters over flat tappets saves about 7 ft./lbs. of torque required to turn the engine (something like that) which adds up, not just power but reduced oil temp and less wear on other parts that have to turn the cam like the timing chain. But you have to have decent valve springs to upgrade the rocker ratio or you will get bad float, which was also in that dyno book. Anyways, just go out and get it, you wont be dissapointed.
 
Well, look at it this way. Weather you gain or loose power, it's a good mod to have. You don't hear people saying "these suck" and putting thier stockers back on. Down the road your going to need it anyways.
 
Viking - the problem isn't with the data - you can find published tests that show HP/torque gains with roller rocker/ratio change installation. You can also find tests that show slight losses to no gain at all. The problem is that people look at one test, or two tests and conclude that because it gained 7 HP here, it'll gain 7HP on any other set up. That's an errant conclusion. Each set up is unique to some extent and when it comes to roller rockers you can't simply extrapolate from one dyno run and conclude things about how that part will perform on another combo. Although folks do that all the time. Where the gains seem to occur is where you have a combo with a mild cam, and really free-flowing intake/heads/exhaust. In that case, the cam is the bottleneck to greater performance, and the extra lift from the higher ratio rockers allows more flow. Significant gains seem to be much less likely in setups that are closer to stock to begin with.
 
Willys - be sure the shop knows how to install them properly. They shouldn't be significantly noiser than stock. You know that you'll probably have clearance issues if you want to use the stock HO valve covers, right? Folks have to remove the baffle under the oil filler, and many people have to grind some of the cast ribs on the underside down to clear the 1.7 rollers. An easy fix is to put a set of stock stamped steel Cobra covers on it.