merchauser

perhaps the beginning of a rabbit hole...….

I enjoy reading about the modifications that are done to increase performance. from minor to major, they are varied, educational, inspirational, and amazing. the HP and torque increases, often verified by dyno tests are impressive. the reports show tremendous HP and torque increases, but my curiosity extends to zero to 60 times, and acceleration. (that's my vice)

I am near the end of required maintenance, and the beginning of power mods, which will be quite modest. next step is X pipe, and then sharktuning. can these modifications be discussed in acceleration terms? for instance, what second gains might be obtained by adding an X pipe? and then by sharktuning? I would be happy to add a second, and giddy if it were more. (if it wasn't a GT, I would be inclined be more aggressive)

docmirror

Gut the interior. Remove the engine, trans driveline. Pickup a Caddy CTS-V engine/transaxle combo, and mount it right behind the front seats. Sticky tires, and you will be all set.

Bigfoot928

more than a rabbit hole. The 928 was not designed to be a street racer. Gear boxes and ratios are far from optimal. blue pill or red pill?

merchauser

ha ha....maybe...??? nah.

Bigfoot928

It's cheaper to buy a corvette, park next to the 928 and drive the one you want when you want.

merchauser

not sure I understand, since your build is clearly one of the most impressive on rennlist. and all about power. were you every looking at a corvette?

simply wondering if anyone has translated these easy/simple mods into seconds v. HP/torque?

docmirror

I have never modded a 928 outside of wheels and tires, so I don't have relevant info. The 928 was the antithesis of the stoplight racer. It would be worthless for American Graffiti. While my commentary was at first tongue in cheek, if you want to have a 0-60 928, start with a shell saved from a graveyard, and just start over.

No part of the 928 design philosophy is geared toward dead stop acceleration. I might have been kidding, but the Caddy CTS-V is 556HP, aluminum V8. Tremec 6 speed, and dual mass flywheel clutch combo. Start with a shell, and get a MIG welder, and get started. I would love to see a mid-mounted engine in a 928 chassis. The Caddy engine trans would be a great combo in a light weight chassis.

jcorenman

Try this website: https://www.carspecs.us/calculator/0-60 That page will translate horsepower and curb-weight into theoretical 0-60 times.

Plugging in 325 bhp and 3500# (for a GT) calculates 5.0 seconds, while the factory spec for 0-100 kph is 5.8 sec. Subtract 0.1 sec for 0-60 gives you 5.7 sec. Just like dyno charts, these numbers are all over the place.

One issue with the 928 is that first gear is the dog-leg, great for touring (where you never see first, in theory) but right in the middle of your 0-60. So that adds a couple of tenths.

But certainly adding power helps, whatever the motivation.

Bigfoot928

Because knowing what I know after the last 22 years of owning my 928 and 20 years into my build I think about all the other things I could have done if I bought a vette, and drove either depending on my mood and had a pile of cash left over. There are no cheap easy mods on the 928.

hacker-pschorr

Multiple supercharged 928's have posted 0-60 times in the low 4's or just under 4 seconds. The fastest ones are usually automatics though, as pointed out above the 928 manual isn't conducive to fast shifting for 0-60 times.

Then you have Todd's car:
https://rennlist.com/forums/928-foru...ip-update.html

Don't let anyone tell you a 928 cannot be a rocket in a straight line, all it takes is money to make more horsepower. How much do you wanna spend?

If I ever find some free time my 87 is the next car to receive a Murf928 Supercharger. Todd, Tim, Mike and I have some ideas we've been meaning to test to improve the existing setup.

Sure we could all buy Corvette's, then you'd just have another Corvette. I'd rather have a really fast 928.
I've spent enough on 928's over the past 25 years I could have a very nice late model Ferrari in the garage instead. I'd rather have my 928's.

SwayBar

You'll have to tell me the details at Vintage weekend.

docmirror

I just don't want to see a nice 90GT butchered to duke it out with blue-tint Toyota on some friday nite Anaheim F&F crash-fest.

Get a roller chassis and do what ya gotta do. Were it me, and I was into this project, I'd likely grab up one of the crate LSn motors, and a 4.30 locker rear end out of a 10" Ford truck. But - that's just me, there are so many ways to go. Torch a giant hole in the center right behind the seat and start welding.

FredR

In some languages and cultures enthusiasm translates to mental illness!

Nothing wrong with sticking an x pipe in and doing a bit of sharktuning- the engine will feel crisper but I doubt you will ever see more than 0.1 of a second on a 0 to 60 time on a good day- the human condition alone probably accounts for more than that.

You can spend $10k plus and get some impressive power adders that wll get you close to a 5 second 0 to 60 but if and when it comes to resale time you would likely end up taking the bits and pieces off the car to sell them on and return the car to stock to get top dollar but possibly at some penalty if the new owner knows what was bolted to it previously.

The real enthusiasts [the ones that flew over the cuckoo's nest] spend a small fortune seeking nirvana and personally I am glad that they do so that we can learn about the potential these cars truly offer but then I suspect we are talking about $50k budgets by the time the entire plot is fully sorted mechanically.

merchauser

ABSOLUTELY no intention of chopping up my GT, and not trying to turn it into something its not. just wanted to know what I might expect with X pipe and sharktune in terms of seconds.

merchauser

fred, your timing is incredible! last night my wife and I couldn't decide what to watch and ended up watching cuckoo's nest!