modify the grand prix ??

[saulgar]

im going to be getting my 3.8 gt heads ported out an wanted to know wut type of rockers to put in an if adding the LS6 valve springs would be a good combination. everything else in the car is stock some minor exhaust , an a cold air intake thats about it !! any suggestion hit me up at [email protected]

1999 pontiac grand prix GT

[GaryFenza]

Get a GTP with a Supercharger, or put a Supercharger on the GT, that would really good. Good Luck

[theblurr87]

Originally Posted by saulgar

im going to be getting my 3.8 gt heads ported out an wanted to know wut type of rockers to put in an if adding the LS6 valve springs would be a good combination. everything else in the car is stock some minor exhaust , an a cold air intake thats about it !! any suggestion hit me up at [email protected]

1999 pontiac grand prix GT

are company websites allowed bnaylor?
anyway zzp sells a set of ER rockers that are great for the N/A 3.8L either go rockers or cam, don't go both.. the rockers will be fine with stock springs i believe.. cams usually need upgraded springs and since you're porting your heads i'd prolly go with a cam anyway. cam is more expensive but you will see more gains. make sure you get at least a 2.5" or 3" downpipe to help with knock and flow and some ported manifolds to go with those ported heads. OR get some small headers like S&S. happy modding.

[BNaylor]

Originally Posted by theblurr87

are company websites allowed bnaylor?

I would highly recommend using the PM messaging system when it comes to discussing or clarifying AF Community Guidelines/Rules and forum policy.

Originally Posted by saulgar

im going to be getting my 3.8 gt heads ported out an wanted to know wut type of rockers to put in an if adding the LS6 valve springs would be a good combination. everything else in the car is stock some minor exhaust , an a cold air intake thats about it !! any suggestion hit me up at [email protected]

1999 pontiac grand prix GT

Per your PM here is my reply.

You did not mention it so to start you will not get the full benefit of mods such as ported heads, PEMs, headers, rocker arms or cam mods without going to a reprogrammed PCM module although not required for minor valvetrain mods such as rockers or using LS6 valvesprings. Also, premium grade fuel will be required in most cases.

The LS6 valvesprings are rated at 90# and are ideal for high ratio rockers that are 1.8:1 ratio. Good for .530" lift with the stock or aftermarket retainers. Best part is they will fit the stock cylinder heads with no machining or extra work, therefore a good choice. The drawback is if you decide to cam up for example even a mild aftermarket cam then you should look at valvesprings rated at 105 lbs.

Companies like ZZP recommends using split ratio rocker arms for a L36 with around 1.8:1 ratio. 1.85:1 for the intake valve and 1.80:1 for the exhaust valve. The problem I have with the ZZP ER kit (Extended Range) is they are stock rockers that have been worked over. IMO you are better off with aluminum roller rockers around 1.8:1 ratio for both intake and exhaust. I prefer SLP kits. The SLP kits cost more as do other aftermarket aluminum roller rockers but worth the extra expenditure because they are true aluminum roller rockers and not the reworked stock. The other drawback to ZZP ER rockers is if you decide to cam up they will not work with aftermarket cams so it could be a waste of money. Probably a good choice if you keep the stock cam and still gain about 15-16 hp but at a higher rpm range. However, peak torque gains are not even worth mentioning except it is developed a few hundred rpms earlier.

Hopes the info helps.