Number crunching

[Performance nut]

There are some great write ups on here discussing various upgrades. Does anyone have numbers on certain upgrades? The reason I ask is because I'm investigating if my '08 Grand Prix with a 3.8L can achieve 300-350 HP at the crank without getting into the engine.

Manifold is ok, rockers... I'm not sure since I have never done them before. Biggest reason I don't want to get into the engine or run boost is because I don't want to pay a mechanic to do mods and pay for go fast parts for a daily driver. Running any sort of boost looks like a considerable amount of work that I'm not sure I can do and it isn't a cheap process even for just parts.

[Speedy1973]

Running any sort of boost looks like a considerable amount of work that I'm not sure I can do and it isn't a cheap process even for just parts.

Funny you say that, i must have friends in high places, as i was gifted with a 80% complete top swap for my car, all off a wrecked regal (rear end accident) i had the opportunity to start the car up and hear it running, ran mint before i started stripping parts, deal was, whatever i could carry i could have.

It does take quite a bit of work going boosted, but in my opinion, if you take your time, take notes, you'll be finished in no time, and you'll learn lots on the way. I've read around here that going boosted is a 500-1000 dollar job (depending on what you do)

If your looking for higher number's, you'r gonna have to go boosted, topswap is the route to go imo

[JoRoW99]

nitrous is probably your best bet then. I dont think you can get 300HP at the crank NA without a power adder, and especially not without a cam/heads.

If you just want it to be quicker: Headers, HV3, intake, rockers, tune. You should be around a stock GTP at that point IMO, maybe a wee bit slower.

Otherwise youre going to be looking at top swapping/turbo.

[Performance nut]

nitrous is probably your best bet then. I dont think you can get 300HP at the crank NA without a power adder, and especially not without a cam/heads.

If you just want it to be quicker: Headers, HV3, intake, rockers, tune. You should be around a stock GTP at that point IMO, maybe a wee bit slower.

Otherwise youre going to be looking at top swapping/turbo.

Nitrous isn't an option. Not looking for occasional power.

[JoRoW99]

ok well like i said youre not going to get 300 crank HP without boost, so id either do what i suggested or just leave it alone.

[ctracer]

you wont hit 300 crank N/A, even if you spend a butt load of money into mods.
if you want that kind of power you will need to go forced induction.

[FordMan77]

Sell it and buy a GXP? Instant 300 at the crank, can be modded and stay N/A.

[Grimsin]

GT D'Overkill - YouTube this guy was sitting around 300 horse...
just sayin.

[Performance nut]

Sell it and buy a GXP? Instant 300 at the crank, can be modded and stay N/A.

About $6000 difference between what I have and a GXP. Would rather not go this route.

[REDCRAPGP]

Unless your going turbo it's not goin to happen. Even then factor in a good turbo/built tranny n other odds and end your probably going to spend well over 4k


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[matt5112]

you wont hit 300 crank N/A, even if you spend a butt load of money into mods.
if you want that kind of power you will need to go forced induction.

intense IS3 heads, and S3 N/A cam and every other bolt on and you might crack 300 CHP.

GT D'Overkill - YouTube this guy was sitting around 300 horse...
just sayin.

How?

300 CHP is 240 WHP if you accept 20% drivetrain losses.

Read that comment, car was setup incorrectly. Claimed power would be there, but again, 250 WHP for cam and ported heads?

Pretty worthless, especially once you factor in the loss of low end power.

Unless your going turbo it's not goin to happen. Even then factor in a good turbo/built tranny n other odds and end your probably going to spend well over 4k

Why would you need a built trans to hold 250 WHP?

About $6000 difference between what I have and a GXP. Would rather not go this route.

Apparently GXPs puke transmissions and stock exhaust. Something to be aware of.

[FordMan77]

Apparently GXPs puke transmissions and stock exhaust. Something to be aware of.

Yes, the 4t80e is known to have issues. Didn't know about the exhaust tho..

Performance nut- Would help to know what your budget is for this. Based on that we can offer suggestions. Is this a DD? Can you afford any downtime?

[matt5112]

Grand Prix GXP still had the 4T65E.

[Fivefingerdeathpunch]

GP GXP has 4t65e

Bonnie GXP has 4t80

[Performance nut]

Performance nut- Would help to know what your budget is for this. Based on that we can offer suggestions. Is this a DD? Can you afford any downtime?

Yes, it's my DD but I'll rent a car for a bit to get what I want. I'd like to keep it under a few grand (say $3000 and not all at once is preferable). I thought there was an adapter or method of keeping my heads and get a GM blower on it but it turns out that it doesn't look possible. I have zero experience with modifying engines and transmissions but I've done a lot of other mods (suspension, cooling, and some body), so I'm a bit hesitant to get into rockers, cams, and heads. Intakes I think will be within my capability as well as assembling "kits" that don't require messing with the before hand mentioned engine parts.

[JoRoW99]

rockers are easy. all you have to do is take the valve cover off.