I have had a thought! - 986 Forum - The Community for Porsche Boxster & Cayman Owners

my89_928gt · 09-23-2005, 09:55 AM

Now I have had my 97 Boxster 5sp for just over a year and half.
I love the car and I dislike it at the same time. The car is just to dam slow. I knew that before I bought it and figured in a couple years I will see what I can do about that. Well in all my researching before buying I did not check into the aftermarket performance area. Well it preaty much sucks. Not much their and what is is way over priced and minumal gains.
The only other complaint was the high speed stabilaty issue. Witch I have gotten used to. Now I'm not saying the car is not stable, just very responsive. Other former 928 owners should understand where I'm comming from on that one.

Now to my thought,
I'm thinking of buying a higher millage used boxster engine(2.5 like I have is ok-they can be gotten preaty cheep)and tearing it down and rebuilding it. Putting in lower compresion pistons, maybe larger valves if can be had, and maybe cam's(though costly) what ever else maybe required like extra cooling. Then put a supper charger on running high boost in the mid to upper teens.
If done right I figure this should be more than I can handle

and if something gose wrong with it, well I would still have my good engine.

Any one know is some has done something like this?

Richard

deliriousga · 09-23-2005, 12:04 PM

Sounds fun to me!!!

How are you planning on taking care of the "float" at high speeds? That's what it feels like to me, kid of like the wheels are still tracking but the body floats so it feels like it's not holding well. I think the 928 does this better because of the weight up front.

I saw a Boxster that was getting a 450HP engine put in when I first got mine, but I have no idea what was going in to get it up that high. It was at a shop I was checking out for future mods.

The aftermarket stuff you were looking at won't come down in price until they Boxsters get older and there is more competition.

MNBoxster · 09-23-2005, 02:16 PM

HI,

You've hit on a real issue here. Unlike a smallblock V8, which is fairly easy to get 10-30-50HP gains, the Boxster Engine, be it 2.5, 2.7 or 3.2 just doesn't readily lend itself to being modded.

In order to see any increase worth the trouble and expense, you have to get pretty drastic. And then you butt into other issues such as packaging, cooling (both for the coolant, but also the engine bay), reliability (especially the tranny) and possibly Brake cooling issues as well.

Given that it is a convertible chassis, I bet you can also overpower a Boxster pretty easily. I suspect you could easily ruin the car.

That said, rather than try to pump up a Boxster engine, I bet the 996 engine conversion, difficult as it is would be a better improvement. It has already been done, so you don't have to reinvent the wheel as it were and you'd get pretty much the same reliability. Also, You would forego all the problems, plumbing and such of forced induction and probably stay under the threshold which would ruin the overall balance of the car.

Happy Motoring!...Jim'99

Brucelee · 09-23-2005, 04:04 PM

The easiest cheapest mod would be an S engine swap.

Ads 50 HP and have no compatibility issues to speak of.

IMHO!

MNBoxster · 09-23-2005, 08:10 PM

Quote:

Originally Posted by Brucelee

The easiest cheapest mod would be an S engine swap.

Ads 50 HP and have no compatibility issues to speak of.

IMHO!

Hi,

This would not be as easy or cheap as you might think. The 3.2 Engine (2000>) is an e-gas Engine, whereas the '97 M96 2.5L is not. This means new DME, Exhaust System, Intake System, Fuel Evac System, Wiring Harness, Plumbing, Transmission Sensors to name just a few.

On the other hand, a pre-2000 3.6 swap would eliminate the need for much of this.

Happy Motoring!...Jim'99

Brucelee · 09-24-2005, 06:50 AM

"On the other hand, a pre-2000 3.6 swap would eliminate the need for much of this"

Not according to my local dealer service swap. I went over the 3.6 swap with them once and was stunned by how much work needed to be done.

Jeph · 09-24-2005, 09:30 AM

my89_928gt, you have the chance to be a 986forums pioneer! Do this for the sake of this opportunity alone! Read on...

Alirght, if you're willing to put up the money for an alternative engine, SAVE it and go with nitrous! Nothing fancy, a 50 shot or something.

A) It's tons cheaper
B) No one on this board has tried it
C) Instant results
D) A lot less work than an engine swap
E) My curiosity will finally be satisfied!

You would be my hero if you do this! Isn't that what you really want?

Now I'm sure MNBoxster will disapprove of this idea with justification using big words, but c'mon... History is at stake here!

(And on a sidenote, I'm not raggin' on ya MNBoxster. I think you are an asset to this forum! That post about spoilers and wings was one of the most interesting things I've ever read on this board! It's good to have ya here.)

MNBoxster · 09-24-2005, 09:41 AM

Quote:

Originally Posted by Brucelee

"On the other hand, a pre-2000 3.6 swap would eliminate the need for much of this"

Not according to my local dealer service swap. I went over the 3.6 swap with them once and was stunned by how much work needed to be done.

Hi,

In fact I noted that the 3.6 swap would be difficult. But, from what I understand, it wouldn't be as difficult as an e-gas conversion.

Happy Motoring!...Jim'99

MNBoxster · 09-24-2005, 09:49 AM

Quote:

Originally Posted by Jeph

my89_928gt, you have the chance to be a 986forums pioneer!...Now I'm sure MNBoxster will disapprove of this idea with justification using big words, but c'mon... History is at stake here!

(And on a sidenote, I'm not raggin' on ya MNBoxster. I think you are an asset to this forum! That post about spoilers and wings was one of the most interesting things I've ever read on this board! It's good to have ya here.)

Hey,

No offense taken. I simply express opinion here. I'd like to think supported by fact(s) and experience, but opinion nonetheless.

I may disagree with what someone proposes, especially for my car, but, in the end, people have the right to do with their car as they wish and I respect that.

It's true, I am not a big Fan of excessive modding to any car. True they become rarities, oddities, even sometimes a testament to someone's ingenuity and skill. But, personally, if I want certain qualities in a car which it doesn't possess, I usually just switch to a car which has them and which were designed into them. But that's just me.

Happy Motoring!...Jim'99

RandallNeighbour · 09-24-2005, 04:07 PM

I've heard a 3.4 fits the boxster better than the 3.6L.

As some of you know, I really, REALLY want to do this engine swap. It's just a matter of timing and cash... I want to get new rims, a respray and new seats first. Then I start saving for a used 3.4, whatever tranny mods are needed, a new brain and a wiring harness.

It may take me two years to save up, but I'm gonna do it. I want the monster Boxster that makes the poser-carrera drivers weep!

my89_928gt · 09-25-2005, 10:10 AM

Wow, plenty of good feed back.
I have thought about the engine swap, the 996 engine is a lot of work and not cheep, but not a bad idear.
The S engine would be the simplest and cheeper way, but only 50hp, him maybe.
Bolt on supercharger kit, not a bad idear and will not realy shorten engine life.
My idear, who knows, lol. Should work fine and reliable and may just be more power than I want.
Oh, nitrious, thought of it. You don't want to use one of the cheep $500 kits as the do not have any safe guards. They have some realy neat stuff to make nitrious very safe these day's. I have a freind that is going to use one that ramps up 4 times I belive it is. That way you don't get a hard slam of power that is so hard on the engine(kinda like a supercharger just a steady build of power no slam). Also, a controler that retards timming a bit with each increse in nitrous, and a monitor that if a drop in fule presure is detected it will shut the flow of nitrious off and save the engine. He will also use a controler for minum rpm and max rpm that nitrous will be allowed.
No, he dose not have a Boxster, lol.
All, that neat stuff for nitrous sounds great but still can't bring my self to do that to my car.
An other car? Maybe.
Lots of options, most of witch I have all ready pondered. I will be takeing my time on this and doing some home work.

All most for got, the front end fealling light at high speeds, I don't think it is realy getting light. I think it is just the mid engine nature of the car. I could be wrong.
The 928 has the engine up front and the transaxle in the back. Those 2 large weights make the car very stable and less willing to chage direction. The boxster has all the weight in the mid area lending to a very responsive car that is quick to change direction even at high speed. That is what I had to get used to.

Stiffer shocks and springs maybe in order with a good power increase. Also, S brakes would not hurt. Though as good as the brakes are should not be necessary on less you get realy crazy.
The real concern is the wimpy clutch.
Though better pads and powerslot rotors will help.

All that, is just my opinion.

Richard

lexuspilot · 09-25-2005, 10:15 AM

What speed do you need to feel this float?

I have cruised at 95 and not felt a thing wrong.

I haven't gone to a track to go faster.

deliriousga · 09-26-2005, 05:47 PM

Quote:

Originally Posted by lexuspilot

What speed do you need to feel this float?

I have cruised at 95 and not felt a thing wrong.

I haven't gone to a track to go faster.

I've heard it's at about 120. Not that I've ever done that.

deliriousga · 09-26-2005, 05:57 PM

I would consider nitrous if I had the $$$ to put in a new engine if it shortens the engine's life.

It seems it would be difficult for any real beneficial mods. I don't think supercharging is possible due to space and the position of the crank pulley. Same with a turbo, no room. A much larger engine won't fit and would probably snap the drive shaft.

The one I saw that was going to 450hp was a $40K job so I'm guessing it was done right, but that's a chunk for something you're not racing it.

nastyboxster · 09-26-2005, 07:37 PM

I upgraded my 2000 Boxster to an S about 3 months ago now. I had the same problem with my old Boxster - I NEEDED MORE POWER!

I think the easiest thing to do is to upgrade your car to an S. You can better handling, brakes and power and best of all it's still very balanced!

In autocrosses, a good driver can outrun turbos and GT3's. Our autocross champion drives a stock S with MO30 suspension and R compound tires.

On the track, an S runs in the same class as 996's and it handles better, so theory, it should outrun the 996's on the track. I learned that it's not just the power of the car that makes it go fast, it's the balance of power, handling, braking and of course most important of all - THE DRIVER. There were faster cars like turbos, GT3's and 997S's with novice drivers that I passed on the track. On the other hand, there were slower cars like pre 90 911's that passed me.

On the street, you can't go that fast without running into traffic or worst yet - the cops. I get my need for speed on the track and autocrosses.

You can read my reviews of cars that I testdrove - Most of them faster than mine, but I still prefer the S over them.

Do I need more power? It would be nice (you can see my wishlist in my review of cars), but in the meantime, I'll learn how to be a better driver......

One more thing, I'm very happy with my upgrade to the S!

Dr. Kill · 10-10-2005, 08:36 AM

Quote:

Originally Posted by Jeph

my89_928gt, you have the chance to be a 986forums pioneer! Do this for the sake of this opportunity alone! Read on...

Alirght, if you're willing to put up the money for an alternative engine, SAVE it and go with nitrous! Nothing fancy, a 50 shot or something.

A) It's tons cheaper
B) No one on this board has tried it
C) Instant results
D) A lot less work than an engine swap
E) My curiosity will finally be satisfied!

You would be my hero if you do this! Isn't that what you really want?

Now I'm sure MNBoxster will disapprove of this idea with justification using big words, but c'mon... History is at stake here!

I think reason E is justification enough.

AndyDickens · 10-15-2005, 11:24 PM

I've had my 2.5 Boxster at an indicated 140mph and see no signs of float or instability. If anything, it was the most stable road car I've tried at that speed. (Others were Jaguar XK8, Porsche 996, 911 and BMW M5.)

11-06-2005, 12:47 PM

I also run my 2.5 tiptronic to 147mph without a floating feel, could it be due to tyre pression or weak suspension?
the other thing that I have heard is that the 2.5 or 3.2 litre engine are apparently the same unit with different bore/stroke, if you rework a 2.5 and change chamber/piston etc..to 3.2 parts would this work out cheaper than buying a full motor?
anyone with an idea on this?