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#74 of 113 S/C pulley upgrade and IAT sensor module
May 09, 2005 (10:47 pm)
I had a 3.5" SLP pulley installed on my '98 GS last Friday. The Buick dealer also installed a module between the IAT sensor and its wiring harness. It's supposed to maximize spark advance by 1-2 degrees, and increase HP. In another forum, two guys said to be careful using it, because it could cause engine knock, resulting in piston damage. Here's a link to SLP's site, showing the module:
Does anyone else think the module could cause major engine damage? BTW, the new pulley increased S/C boost by 3 psi (from 7 to 10). I noticed a big difference in acceleration. SLP says gains up to 25 HP are possible with this pulley. The bottom line is should I also use the module?
#75 of 113 Re: S/C pulley upgrade and IAT sensor module [jpstax1]
by Mr_Shiftright HOST
May 10, 2005 (8:40 am)
Well if it doesn't disable your knock sensor I don't see the problem. If it does disable it or change its tolerance (the map of what octane it will tolerate), then you either have to be sure not to lug this engine or use higher octane fuel.
It's the combination of pinging plus lugging the engine that's a piston-eater.
Actually as I think about it, a 1-2 degree bump in timing isn't a whole lot.
10 psi should be okay because your engine was designed for a SC to begin with. However, higher boost will seek out and magnify any defects you might have in compression or head gasket sealing, so it's important that you only do this with a very tight engine.
#77 of 113 high performance turbos
May 14, 2005 (1:32 am)
First, most turbo cars run in vacuum most of the time, and idle just like a stock lexus. They get good gas mileage because in vacuum they don't make any power when in vacuum. My bud's Toyota Supra Turbo car gets about 20mpg city and 26 highway and makes over 1000HP with a large turbo idles quietly at 650 rpm... (here is a link http://www.to4r.com/member.php?show=garth.weaver )
Secondly, exhaust restriction you speak of is vital to producing low range horsepower. You need a certain amount of back pressure to create horsepower in the low rpm ranges. It is not an issue of back pressure with forced induction at max power- otherwise my bud's car couldn't make 1000HP. (read this about turbos: http://www.turbo-kits.com/how_turbos_work.html )
Remember this: You only burn more fuel when making power. So in english, if you keep your right foot out of it, a low compression turbo motor will get good gas mileage provided you can keep your right foot in check. (here read the tech in this link! http://www.inductionmotorsports.com/index.html?turbos.html )
Turbo' car's drawback was emissions control. not gas mileage.
Thirdly if you were to create a lagless turbo, it would have many good advantages, you can run a larger compressor than normal. That allows the compressed air to be cooler and denser at a lower boost level. Translated in english, You no longer will need intercoolers and you will make more power at lower boost levels than previously possible. I design turbos and my company is creating the first lagless prototype turbo. Should be finished this year.
#81 of 113 Re: high performance turbos [blackcactus1]
May 27, 2005 (1:19 am)
Which company is this? Is this lagless turbo a VGT? If so, are you using an existing design or
model like from Holset's? Or is this something like Garrett's hydraulically driver compressor? What sizes/specs will you offer? And while I agree with the higher peak effeciency of the larger turbo when spun up to its range, I don't think you can eliminate the need for an intercooler..
.. while I know many will think them ideal for smaller engines, I think there may be an even bigger market for larger engines! Simply because I think most in that crowd already care or are more conscious about power delivery to justify the extra cost
#82 of 113 Re: high performance turbos [jimveta]
by Mr_Shiftright HOST
May 27, 2005 (7:22 am)
Most larger engines respond better to twin turbos, both to reduce lag and also because it's an easier fit, one turbo for each bank of a V type engine.
#83 of 113 300D Turbo upgrade
Jun 15, 2005 (8:45 am)
I have an imported 1984 300D with no turbo. The engine is the same 5 cyl., but the fuel injector pump is different than the regular turbo engines. I have a turbo off another car that I want to install in. Do I need to do any aditional adjustments to the injector pump, exhaust pipes, etc. Thanks