While browsing ZZP as I have often been doing lately I came across a few engine modifications that caught my eye. An aftermarket camshaft that adds 20-30HP and can take UP to 1/2 second off your 1/4 mile time on a N/A 3800. It costs something like $330, not sure what installation charges are. Then the are the rockers, they also hover around $300, and claim to give you up to 20HP, or around there. Reviews on there say the rockers give your car a better tone, increased gas mileage, etc. But they say the rockers can't be installed on an aftermarket cam, which leads me to believe I can't have both, I have to choose. Any suggestions? Recommendations?

 

The average shade tree mechanic can install rockers on his or her own. Camshaft installation on 3800s requires alot more work and generally requires a higher degree of skill/knowledge.

Higher ratio rockers are a great mod. So is a more radical camshaft. The cam will get you better gains, but is it worth the extra aggravation? That's up to you to decide.

 

go with the cam i think you will like how you exhaust sound after it's install

 

Stock your car does ~160whp; almost every cammed NA 3800 dynos 200whp or less (and some of these cars have some fairly significant mod lists, including ported heads). In comparison, a stock SC 3800 dynos 200 whp. So even a good cammed NA 3800 is going to have a tough time competing with a stock SC 3800. Just something to think about.

For most of the larger cams- you need to add a stronger timing chain, and stronger valvesprings to that price. Installation is pretty difficult- you have to do quite a bit of work to get it in there.

For rockers go with the ER ratio ones for an NA setup. They're far easier to install- and you can run stock springs and the stock chain. However, don't think that the gains off rockers will be anywhere near what a cam is. You end up with a really heavy lift, no duration setup- so the gains are noticeably worse than a cam. The only upside is that rockers don't move your powerband up in the RPM range so much. This is pretty drastic on the larger cams.

The L67's don't have to deal with this nearly as much because the blower adds more power than the car can hook out of the hole anyways- so moving the powerband up for them, especially on heavily modded setups, helps them quite a bit. Not to mention, the L67 isn't as picky to getting the perfect cam for your application- and they get way more power gain because they can typically drop a significant amount off thier pulley size by doing a cam, so you get the 20-30 hp gain from the cam, plus another 20 hp gain from dropping a couple pulley sizes.

A cam will vastly change the tone of your car- you'll add lope, volume, and the actual tone will change too. The audible change with rockers is virtually 0.

That is not true- I have an Intense stage 3 blower cam with HS 1.7:1 roller rockers- so it is possible to run both.

The thing is, the big 1.9 ratio rockers are what you want to get the most gains out of rockers (ER's for NA- theyre 1.8 1.9 split). However, with most cam's, they increase the lift so much that if you put 1.9 rockers on top of them- you make for way too much lift, and your springs bind up. The idea is, you need to see how much lift the heads you plan to run can handle (be it stock, or aftermarket)- and then make sure the lift at the valve with either the cam and stock 1.6 rockers or the cam and whatever rockers you plan to run do not exceed this value (keep in mind, you need a little extra play room here too).

Really, you also need to think if you're planning to do both- why don't you just go with a bigger cam? If you pick a baby cam and want to add more lift with higher ratio rockers; why not just go with a larger cam and keep the stock rockers? Then also keep in mind that the bigger cams are really built to work with ported heads and a higher stall TC.

Personally, I wouldn't bother with a cam on an NA 3800. Unless you have some fetish to build some hardcore NA drag racer setup to be different- the NA 3800 isn't worth camming for a street car. The bigger the cam, the stiffer the valvesprings, the higher the powerband moves up (so you really begin to need a high stall TC to get you into the powerband), the more the wear on your timing chain, the rougher the idle, the harder it is to daily drive, the worse the gas mileage, etc etc

I think you can see where I'm going- a cam will drastically change the car- especially if you go with a larger one; and you just have to wonder if its worth all the time and hassle to still run just as slow as a stock L67. There is a reason why a lot of the guys that were originally camming thier L36's quit once they started getting spanked by L67s as the market took off.

IMO, if you just want another cheap bolt on to add to your mod list to pick up 5-10 wheel horsepower, drop some ER rockers on there and be done with it. If you want to go significantly faster- forget doing a NA cam, and start thinking about how you're gonna boost your car.

 

yo bum, with your intense stage 3 cam and 1.7 rockers setup how much hp you think you gain? from what i read alot of guys saying you will not see any gain at all by going little higher on the rockers ratio, unless you have heads done.

 

Thank you very much for all the information BumpinMonte96, it was very helpful. I didn't know a CAM did such radical things to the engine and could cause so many other problems. I'm really not looking to run with the L67's per se, or any S/C car seriously, I just want to give my car a bit more noticeable pep, while still keeping it a very reliable and easily maintainable car that will last me awhile. So a 10HP gain is about all I'll get by going with rockers? Is there anything else I need to upgrade, replace, or worry about when doing rockers?

 

ER Rockers are actually 1.85 in the Intake and 1.8 in the exhaust.

 

I guess I have no idea what rockers are or how they work, but I was even more surpised to see "intake" rockers and "exhaust" rockers, so you can have two sets? How do they work? What do they do? Are there any downsides to having these?

 

[QUOTE=Quatermain N/A SS;154152] really not looking to run with the L67's per se, or any S/C car seriously, I just want to give my car a bit more noticeable pep, while still keeping it a very reliable and easily maintainable car that will last me awhile. QUOTE]

that's what i used to say when i done my first mod. i said that too few months back when i had full size ic installed. now i'm thinking of custom cam grind and 1.7 rockers.

 

They are only one set, but it refers to the side of the engine that they are on. ER Rockers (which are best for NA applications) are called ER because they stand for Extended Range Rockers. You will get 12 rockers, 6 for each side of the engine. Only they have a different ratio depending on the engine side, because through research ZZP found that splitting the ratio for NA applications is more beneficial.

Stock rockers are considered 1.6 Ratio. That means that the stock rocker opens the valves 1.6 times the amount of the Cam lobe. The higher the ratio, the longer the valve stays open, the more air flow rates go up, and more air means more power (to an extent). They researched with different ratios and found that 1.8 for the exhaust side, and 1.85 for the intake side gave the most results (on NA while keeping the stock springs)

Of course since you are altering your air flow, after you do rockers you should get that car tuned. Also since you are doing the work of taking off the upper intake manifold and valve covers, it's a good time to put the HV3 in at the same time so your upper RPM band gets to use more power.