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nrmcj
06-02-2003, 07:06 PM
i thought i'd make a thread of all this tech stuff, cuz once in a while i think up a good question that im lookin for an answer for, and who's better to ask then bluemax!? ^__^

well today's questions is... are camshafts a good investment when you're upgrading a car? from what i know, cams change the valve open/close times... this affects how much overlap, and how much air gets in/out... but... is this going to affect the engine in any negative way? and basically what we're talking about is allowing more fuel to burn, right?

thanks! ^__^

bluemax_1
06-03-2003, 01:55 PM
Funny:D Ok, let's see. Camshafts... well, there are several things to consider about camshafts. First, is the vehicle SOHC or DOHC? You'll have a little more control with DOHC since intake and exhaust valves are controlled by separate shafts. Also the three things to consider about the camshafts are lift, duration and overlap.

There are many different ways of modding the camshafts but I rarely EVER hear anything good about regrinds. That's where they take a stock camshaft and grind the cam lobes for a different profile. If all you're doing is removing material from the original camshaft, then you're severely limited in how much alteration you can do to that profile. The better companies tend to use new cast shafts that are then ground to their specs. As far as different companies and their shafts and different grinds go, that's the really difficult part.

The stock camshafts on the car are ground to provide the best compromise in fuel economy, daily driving and power. Obviously if you want maximum power, these camshafts aren't the best, however, if you change any one factor, the others are altered as well. Most of the time, aftermarket camshafts with very aggressive profiles make the extra power high up in the rev range and end up losing power and torque down in the lower ranges. They'll also be less fuel efficient and you could have problems with rough idling and daily driving in any condition except for high revs at WOT.

As far as how much power you'll add with different camshafts, depends on the engine and the camhaft obviously. Some engines have more aftermarket options than others but seriously speaking, unless you know of a person who has the same car you're trying to modify and has a set of camshafts that have been proven to increase power while retaining driveability, this is one of the mods that I would seriously reconsider. I've known people who've used aggressive cams, some for race only and some that are called street-tuned. While one or two were lucky enough to find something they liked, a lot more ended up having to try many different shafts and still not finding something that worked well especially for cars still meant to be street driven.

Have to remember, unlike turbos where you can control boost pressure or A/F which alows you to change the fueling, camshafts are something that you can't modify once you put them in, aside from changing the timing with adjustable cam gears, in which case you're changing overlap and advancing and retarding. The profile of the cams is set though, and if they aren't good, there isn't much you can do about it. The power gained from aggressive camshafts is also generally not a whole lot. if the car is NA(normally aspirated), then camshafts are one of the few options you have to increase power, but if the car is turbocharged, you have lots more options that can give you more power without adversely affecting the driveability.

This is one of those mods that generally proves to be a trial and error mod. You might be lucky and be happy with the first set of aftermarket camshafts you get, or you could end up having to buy and try many different ones to find something that works for you.

nrmcj
06-08-2003, 03:55 PM
oh... hmmm, i guess then it's more of a hit and miss kinda thing... i noticed that NA engines dont have a whole lot of options in terms of increasing power, and that this was one of them... i've heard people reccomend the stage 1 or stage 2 cams from Skunk2, because they are made for street use, not full racing... heh, well looks like this is going on the "maybe" list... =) thanks again for the info :D

oh yeah.. and hows the VR4 coming? ^__^

bluemax_1
06-08-2003, 06:05 PM
Yeah, the whole camshaft thing really is dependant on finding someone with the same engine who's tried them. The only ones I can vouch for are Schrick and Neuspeed camshafts for the VW Golf. The Schrick 268 and 272 degree shafts are pretty good.

As for the VR-4, right now, just waiting for the tranny shop to finish putting my tranny back together and then I'm all set! The engine's prety much all back together now, just waiting for me to bolt on the tranny and put it all back in. Then it's all a matter of self-discipline and control as I wait for the 500 mile break-in period to roll by.

ShadowMage
06-09-2003, 01:14 AM
hey ya'll! :) Been a while since I last posted...been kinda busy. I've been observing every now and then but haven't stopped to post. Anywho...I don't plan on buying these but I just thought it'd be an interesting little tidbit to throw out there. I think they're kinda funny but anywho...

http://www.acturbo.com/index2.html

ACTurbo, makers of the electric turbo. Get's a max of 2, count'em, 2 PSI of boost! :eek: Woohoo! LOL :D They offer twin turbo kits as well and in a wide range of colors (because they have a plastic casing)! :D :D :D

hehe What's your take on these bluemax?

bluemax_1
06-09-2003, 01:43 AM
Wow, electric turbo... 2psi.... amazing... hmmm... can anyone hear the sarcasm?:D

All things considered though, after looking at the website, I might get one of these. Seriously.

See, they say that it's thousands cheaper than a regular turbo, so considering I can get a nice turbo for oh... $1500, and semantically speaking, the minimum number that qualifies as 'thousands' would be $2000. It would seem that they're going to pay me at least $500 to put that piece of s#@% in my car. Hey, I could always use another $500.:D

Good link, very amusing. At least it's conceptually better than the Turbo Zet. A stupid little device about the size of a computer ventilation fan that you could stick in your intake pipe and would supposedly boost the intake pressure "like an electric turbo" All sorts of stupid claims were made about that thing.

tinyrc
06-14-2003, 01:00 AM
Cool initiative Pie; I'm thinking about adding a few sub-forums to the Misc. area, such as 1:1 Cars, Tuning, etc. - what do you think?

nrmcj
06-14-2003, 02:34 PM
hm... you know tiny, that sounds pretty good... im not sure how many people are into real cars on this forum, but it's still a great idea... probably just one forum-thingy, w/o the subforums...

:D

hey bluemax... (hehe) thanks for the info..

i was wondering.... about clutch plates. i noticed there's a whole assload of different ones, not only different brand or material, but there's some really strange ones... the generic ones that are round with holes,... and then there's those weird ones that look like a + sign, with 2 holes in each... thing. (ooo man.. i sound like a foo)... some are called racing clutches, some are called street.... any clarification here?

tinyrc
06-14-2003, 03:26 PM
Done! :)

bluemax_1
06-15-2003, 04:56 AM
Wow, a whole new forum category...:eek: :D

Well, as far as clutches go, there are a few things to consider. The first thing which limits what clutches you will be looking at is the holding capacity. This is how much torque the clutch can stand without slipping. This of course will be dependant on your car and also how much it has been (will be) tuned.

There are 3 main parts to a clutch. The pressure plate, the flywheel and in between the two is the clutch disc or friction disc. The design of the pressure plate and the springs on the pressure plate will determine how much pressure it can apply to force the clutch disc to the flywheel. This also generally determines how 'heavy' the clutch pedal feels. Generally the greater the capacity of the pressure plate, the heavier the pedal will feel. There are designs which change the leverage from the stock setup, which allow a stronger clutch to feel the same as the stock clutch though.

As for the clutch disc, there are many types, but they basically divide into sprung hub and solid hub discs. Sprung hub discs have coil springs between the hub and disc to absorb the shock of engagement when the clutch first starts to 'catch'. Solid hub discs have no springs. They are usually used only in very high torque situations where a sprung hub might not be able to cope with the load. There are also different kinds of friction materials, ranging from organic (most stock clutches) to kevlar, bronze metallic, sintered iron and carbon. They all have different characteristics, differing in how much friction they have and how aggressively they engage, and also how durable they are. It would be quite an essay to review the differences in these materials and how they perform under various conditions, but here's a link that has a lot of basic info. Note that since this particular company doesn't make carbon clutches, they don't have any info on those

http://www.ramclutches.com/Clutch%20University/clutch_university.htm

BTW, this isn't an endorsement for their clutches. I've heard some decent things about their clutches, but have no personal experience with them. The link has decent info on clutches in general though. As for my VR-4, I've got a single plate carbon-carbon clutch in it by RPS. Holding capacity of 600ft-lbs. Since I'm not predominantly a drag racer, this clutch works out nicely for me. They have a twin disc carbon-carbon good for 1000+ft-lbs.

takumi_drifto
06-16-2003, 12:46 AM
Just wondering.. this car can be pretty sweet...

What years come with turbo?
What years come with AWD?
Why did they stop makin the turbo model?
How come the generation 3 model looks alot like a pontiac?
This isnt really a japanese car is it?
Why Did they stop making the lazer/talon..


Thanks alot, somebody just answer those few questiosn if u no them!!! MY DAD WANTS TO GET ME THIS CAR! :D

binaryterror
06-16-2003, 08:29 AM
Originally posted by takumi_drifto
Just wondering.. this car can be pretty sweet...

1.What years come with turbo?
2.What years come with AWD?
3.Why did they stop makin the turbo model?
4.How come the generation 3 model looks alot like a pontiac?
5.This isnt really a japanese car is it?
6.Why Did they stop making the lazer/talon..

Thanks alot, somebody just answer those few questiosn if u no them!!! MY DAD WANTS TO GET ME THIS CAR! :D

I can answer a few of these...
4. they don't look like pontiacs to me...
5. and 6. It is really a DSM (Diamond Star Motors). This was a venture between Chrysler and Mitsubishi. Chrysler did NOT buy any part of Mitsubishi, it was a way to showcase the 3000GT and Eclipse in American clothes. During the production of the DSM cars Japanese car sales were down due to the influx of "American is better". The Dodge Avenger is also the last DSM car to my knowledge. DSM then split up as sales slowed...
It really is a Japanese car. To be honest it is also easier to buy mechanical parts for the Eclipse, the bodies were however different.

The only down side to the Eclipse family is the AWD puts alot of strain on the already weak transmissions. The DSM Eclipse line has by far the weakest manual and automatic transmissions ever. They now (since F&F made them known again) have parts to make the driveline somewhat stronger, but it seems DSM made it only to support the power and not much more. A good hard launch in my friends AWD Talon tsi manual caused the trans to be totally destroyed...his car now with the rebuilt trans hits high 11's.

takumi_drifto
06-16-2003, 12:54 PM
oo ok coool..


BTW a black 3 gen eclipse makes me see pontiac for some reason.. or any dark colored shinney paint job.:rolleyes:

bluemax_1
06-16-2003, 04:15 PM
An awd Eclipse is a pretty nice car actually. Lots of mod parts available for it, especially the turbo 4g63 engine.

Here are a few more answers to some of your Q's. There are 2 Mitsubishi Eclipse turbo models, the GST and the GSX. The GST is FWD, the GSX is AWD. In my opinion, the GST is not very good. There is a limited amount of hp you can effectively put to the ground in a FWD before you encounter severe traction problems and problems with torque steer. All the FWD cars you see making fast runs at NIRA and the IDRC have wheelie bars. You can't drive a street car with a wheelie bar on it.

As for the last years they were made. I believe '99 was the last year for the GSX and GST models. The 2nd gen models, known as 2G to afficionados is better in several ways, but has some downsides too. '94-'99 cars have a remodeled bumper that will fit a larger front mount intercooler.

Mitsubishi stopped producing the GSX and GST for several reasons. for one thing, although the GSX was the flagship Eclipse whose image sold the Eclipse line, GSX's did not account for sufficient sales percentages. Also, in Japan, the Eclipse is not popular, considering they've had the Mitsubishi Lancer Evo, which became immensely popular from late '93. the only reason they retain the Eclipse line is because it is the No.1 selling Mitsubishi in the US. I never agreed with their decision to drop the turbo models though.

One of their reasons for removing the turbo cars from their line back in '99 was the fact that in the mid-90's Japanese car manufacturers came to the conclusion that the average American didn't know how to take care of a turbocharged car and didn't understand that it needs a little more care and maintenance to continue operating at full potential. Customers driving turbocharged cars and redlining the engine shortly before shutting it off were damaging turbos unknowingly and this resulted in the perception that turbocharged cars were unreliable and prone to engine problems, an image no car company wants. You'll notice that although there were several Japanese companies marketing turbocharged cars in the late 80's to the mid-90's, with a selection available like the Subaru SVX, the Supra Turbo, RX-7, 3000GT VR-4, Eclipse GST and GSX, 300ZX and such, by the late 90's these were all gone.

Fortunately, with burgeoning interest in performance imports and the aftermarket scene and (much as I hate to say it) additional interest caused by movies like 'Fast and Furious', plus gaining interest in WRC events and awareness of certain cars from Gran Turismo, some Japanese manufacturers have decided that the American market may now be ready for Japanese performance cars, and so they're bringing in the WRX, the Lancer Evo, and soon, the new Skyline GT-R.

Also, you might find that the 3rd gen Eclipse looks a little like a Pontiac mostly because of the 'ribbed for nobody's pleasure' styling. I don't like it either. But then again, once they decided to remove the GSX from the line, Eclipses became 'Automobilia non grata' to me anyway.

As for the comment that DSMs have inherently weak transmissions there is some truth to it although it is misleading. The simple fact is that awd cars have an immense amount of traction, and repeatedly trying to launch the car like you just stole it puts an incredible strain on the tranny. Proper driving technique and shifting can avoid these problems, however, if you intend to drag race a GSX, there are several companies that can beef up the transmission for it. Kormex Transmission Parts in California is one, Team Rip Engineering in Michigan is another. In fact, I'm currently waiting to get my transmission back from TRE.