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Looking for some advice top swapped grand prix

Tonkin2000GT

Tonkin2000GT

New member
Okay so I have a 2000 Grand Prix GT that I top swapped and have many mods all from ZZPerformance. I'm looking for advice on what to do next, here's a list of my current mods. I started out with building the whole COMPLETE motor naturally aspirated then wanted more power which would be why I have a GT1 cam. The motor has just 5,000 miles on it.

-ZZP tune
-GT1 cam, gm #90 valve springs, comp retainers
-bored .020 over federal mogul pistons
-L36 heads ported (gasket matched intake and exhaust), SS valves, autolite 104
-Gen 3 blower 3.4 mps bought it before I knew there was a GenV ZZP said they could make it as good as a GenV had them port inlet and outlet
-SSM90 setup but went with a SFI supercharged crank pulley so i can run smaller SC pulleys, 8 rib SC belt
-ZZP ported LIM to match SC and extra gasket matching to match up with my heads, coolant holes plugged
-ZZP modified fuel rails, ZZP flow matched L67 injectors
-Northstar throttle body, LQ4 MAF, SLP intake
-high velocity oil pump
-new stock lifters, push rods, rockers, connecting rods, bearings etc
-ZZP front power log, ceramic coated crossover, and ceramic coated rear manifold
-ZZP 3" down pipe no cat, SLP 2.5" loudmouth catback exhaust
-No EGR, NO evap
-I have Aeroforce gauges I currently have 0 knock on 93 octane gas, I cant run E85 don't have it in the area

I want to get to a 3.1 pulley or the 12's in a quarter mile this is what ZZP says:
-Double roller, crow cam 140lb valve springs, SSIC, run a 3.25 pulley they said a 3.1 will be to aggressive on my set up? thoughts? Some people say SSIC are pointless I wish I could run a full size unfortunately I cant. So I asked ZZP if I should put a XP cam in they said not worth the $ or time maybe 10hp gains thoughts? I still think 140lb valve springs are to much ZZP claims 3800's just need more spring from the factory it will run better, rev higher and have 0 valve float? Let me know what you guys think I'd appreciate Thanks.
 
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your gonna need a ic to get smaller then a 3.4 pulley safely.

that cam, is that a n/a cam? if so they dont work as well as a blower cam does.
 
If you're just looking to make a fast pass at the track, get a nitrous setup. A 75 shot, some race gas and a 3.2 pulley (just for the track) should get you in the 12's. For a daily driven 12 sec gp you're gonna need either a full size ic, e85, or a ported heads big cam great tune setup. And a new tranny
 
Btw I'm pretty sure 140# valve springs and a double roller would be way overkill. That shouldn't be needed until you start porting heads, or adding a huge cam or rockers with a cam. Zzp is kinda full of sh1t if you haven't noticed. Get a better tune as well.
 


Yes a GT1 cam is for N/A I did that first that's why then realized I wanted more hp. The car is my DD in the summer I drive it 6 months out of the year because of snow where I live in western NY. I have a ton of money in the car its been painted and just everything I was told to come on the forum for better advice. Anyways I don't know or have any resources to have it tuned locally. Just looking for more hp is it worth pulling the cam and putting a xp in? My GT1 cam is 210°/210° .507 lift intake and exhaust. Is a double roller better seen alot on here that people don't like them? Why would zzp tell me to run such a heavy spring? Is a ssic worth doing?
 
those springs are over kill for sure. a double roller chain needs to be machined too.

i dont know a whole lot about cam spec's but most who used n/a cams with a blower changed it down the road.

ic is totally worth it.
 
Yea I asked zzp several times why such a heavy spring they claim 3800's just need more spring and it's benificial to rev it to 6800-7k with that being said I need heavier valve springs so I don't have valve float. Yea they said machined pump cover and thinker front gasket for double roller. I meant is the short stack intercooler wOrth doing since I can't use a full size on my set up?
 
Why cant you run a full sized ic? Frosty fit a full sized ic with a gen 5 on the ZZP ssm90 lim iirc.
And you would want a bigger cam than a XP.
 


You would need those springs if you want to Rev that high, but why would you Rev it to the moon? Being a blower setup you're gonna be a torque monster, not a high hp machine. You might get an extra 10whp revving it up past 6400ish. Probably not worth the wear on a summer dd setup. And you would need 1.6 or 1.7 rockers and maybe head work to get full advantage of revving that high with your current cam. I wouldn't do it. You'll gain the advantage of being able to drop a few sizes with a ssic. Might be worth it if that's you're goal. But I'm with slick, you should be able to get a full size in there.
 
If you have #90 ls6 springs I would consider switching to 105s or 130s at most. 130s should need a double roller and the accompanying junk. I would only do that if changing cams or adding rockers. Otherwise leave it with the 90s.
 
Right now I'm reving to 6400/6500 zzp said that's pushing it with 90's that I probably have valve float now put 140's in with double roller. I'm not sure what to do looking for a decent setup everyone says something different I really don't want to Rev higher zzp says it's benificial with that cam. Zzp said ssic is the most I can do they have tried using a full size it doesn't work with ssm90 because they can't get the car to idle right with that much of a injector angle.
 
Why can't you use a FS Intercooler?

To my knowledge, unless a custom cam, none of the 3800 cams produce any power increase in those rpm range (6800+), so not needed.

2x on the Wrong Cam... Maybe just 10 HP using the XP, but has correct duration/overlap for blower, so otherwise wasting (-10+) HP.

GT1 cam specs - 210/210 .317/.317 113 and those numbers don't work well with a Blower Motor, there is no blower cam, even stock that has same duration intake/exhaust... You'd be better spending the #140 spring $ towards replacing that cam. Can't believe you have 0* KR on that cam, with Topswap and ZZP's boxed tune. Wonder if they turned something off?

Talking to the vendor who makes $$$ selling snake oil is not always the best way to go about things.

There are tried and true methods to getting where you want to go and post #5 & 6 gives you an idea...
 


Like previously stated ZZP is full of ****, do yourself and your car a favor and stay away from them for help with anything. Ask people on here who actually care about making your car safe and fast, and not just trying to get you to buy parts you do not need.

Sent from A Galaxy Far Far Away
 
On the dyno my e85 setup made peak power around 6100 with 105s and an s1x. I had some knock issues to work out, but even knock free I doubt you would gain much over 63 or 6400 rpm unless extremely modded. Your choice as always, but parts break down way faster going that high often.
 
Okay well that's why I'm on the forum so xp cam what springs? Double roller? Can I use stock lifters, push rods with xp cam? Well what do you mean zzp erasing something? On my current set up hammering on it wot the only KR I see is quick blips up to 0.6 highest I've seen is 0.8 and then straight to 0 zzp says that's normal on wot those blips are while shifting I have 0 KR that's with aeroforce interceptor gauges.
 
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