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Looking for opinions on what mod to do next

G

GTPguy87

New member
I am new to this site but have heard very good things about it, so I figured I would give it a try. I have a 99 Gtp and I would like to hear some opinions on what my next mod should be...Cam? Rockers? Let me know. Below is a list of my mods.
* 3.4" pulley,Headers and full magnaflow exhaust,PCM tune,LS1 TB,CAI,upgraded injectors,ported s/c,180* T-Stat
 


If you want power throughout the RPM's go with a cam. Otherwise if you are content with power coming in about 4K RPM rocker it.
 
Ok thanks. If I go cam what cam would you reccomend? If I go rockers what size rockers/brand would be ideal and what valve springs would go with them?
 
you should get a cam. everybody who does rockers and stays s/c regrets not going right for a cam.
some good daily driver cams are VS or XP. id go with Crowe #105 springs. and a tune to really squeeze the power out of w/e pulley you manage to put on there.
 


How difficult is it on these cars to install a cam? Never done one on a fwd car before. What price range does the xp cam go for and will it operate safely on stock valves,rockers etc?
 
Ok thanks guys for the info..Cam it is then :) Any thoughts on where I could get a scanner for KR and how much they cost?
 


If staying with stock heads then I'd recommend a S1X. It was proven they back half better than the XP cam.
 
Who sells a good quality aftermarket head for these motors? ZZP? Edelbrock? Our stock heads and motor are steel so I wouldnt want to change the heads to alluminum. Also what price would they go for roughly and how much power increase would I expect?
 
Expect to spend around 3000 for aluminum heads if you can find them.

GM made a few sets, and so did ZZP.

Aside from flow, what benefit do you expect from them?
 


Ok i was just curious. I think I will stick to doing the cam. I want to run my 3.25 pulley without knocking. I had it on before and got KR but with the 3.4 I run 12Lbs of boost no KR. Any other mods that you think could make me run a 3.25 without?
 
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If you have 12psi on a 3.4", then you need more flow mods.

To add, you're on a stock valvetrain with an LS1 TB...why? Not needed.

Also, catback is worthless as well...giving you no power gains.

Injectors are not needed either, stockers flow fine down to a 3.1"~.

I'd do more research before looking further into mods if you're asking about Edelbrock heads for a SeriesII 3800.
 
Ya I wish I knew more about the car as I bought it from a very well known local mechanic who raced it. It may have more mods done internally. I haven't got to ask him yet but he knows speed so I doubt he installed any mods that were"useless". I do however know it ran high 12s in the quarter. I have only ever owned camaros so thats why I asked if edelbrock made heads for them. Anyways thanks for your help
 
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