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Engine Specific Info and Questions => IDI Engine => Topic started by: ObscuredByClouds on June 20, 2009, 06:57:09 am

Title: Quarter Mile: 18.267 @ 75.02
Post by: ObscuredByClouds on June 20, 2009, 06:57:09 am
ET: 18.267
Trap: 75.02
60 foot: 2.687
RT: 0.401
1/8: 11.7 @ 60 (lol 0-60 time)

By 3rd gear boost held at 26psi and I just didn't really accelerate. Aside from over boost, I think an intercooler will help with the top end issues.
Title: Re: 1/4'in LOL
Post by: MJF on June 20, 2009, 08:28:55 am
Lower your boost, turn more fuel and add intercooler and youŽll be in 15Žs ;D You are already faster than stock TDI (http://www.kotinet.com/matti.farm/img003.jpg)...
Title: Re: 1/4'in LOL
Post by: Smokey Eddy on June 21, 2009, 01:49:52 am
there is such a thing as too much boost?
Title: Re: 1/4'in LOL
Post by: MJF on June 21, 2009, 04:26:21 am
Quote from: Smokey Eddy on June 21, 2009, 01:49:52 am
there is such a thing as too much boost?

Yes. Use as low boost as possible.
Title: Re: 1/4'in LOL
Post by: 8v-of-fury on June 21, 2009, 12:55:42 pm
As LOW boost as possible? please explain as to why people always want to go for the biggest boost their engine can handle then? I'm right confused now lol
Title: Re: 1/4'in LOL
Post by: 8v-of-fury on June 21, 2009, 01:28:51 pm
OHH so in a way its almost like your cramming in too much air type thing? not getting a good even mix  of fuel and air for the engine?
Title: Re: 1/4'in LOL
Post by: jtanguay on June 21, 2009, 02:01:00 pm
Quote from: 8v-of-fury on June 21, 2009, 01:28:51 pm
OHH so in a way its almost like your cramming in too much air type thing? not getting a good even mix  of fuel and air for the engine?

the turbine efficiency range is 17 psi or so for a K14, and about 20 psi for a K24.  once you go above that, the exhaust back pressure becomes higher than the intake pressure.  so in theory the engine has to work harder to sustain the boost pressure.
Title: Re: 1/4'in LOL
Post by: OM617 on June 21, 2009, 03:57:40 pm
More boost than needed to burn the fuel injected restricts the exhaust and excessively heats the air. At 26psi your charge air is 380*f, at 15psi its 220*f.
Title: Re: 1/4'in LOL
Post by: RabbitJockey on June 21, 2009, 08:35:53 pm
i did low 16s with my 1.6.  closed wastegate on a k24 25-30psi, turned up fueling, cone filter, and 2 1/4 inch exhaust off the stock cast down pipe, in a mk1 jetta coupe with no ac or sun roof.