Some JWT TT info from an FI master.
Some JWT TT info from an FI master.
[15:22] azivman3: I forgot more about FI on a Z than you know
[15:22] azivman3: you want to discuss
[15:22] azivman3: get the ball rollin
[15:23] taurran2004: well, although I would love to hear about your APS TT and how great it is. I've already heard enough
[15:23] azivman3: you haven't heard much
[15:23] azivman3: lots more to discuss
[15:23] azivman3: what you think of the JWT TT setup?
[15:24] taurran2004: what do I think?
[15:24] taurran2004: I think its a great kit. Lots of potential
[15:24] azivman3: HP potential?
[15:24] taurran2004: although it might not include a mandatory fuel return system, like the all powerfull aps tt, its still nice
[15:24] taurran2004: not that I really care, I've already made my choice
[15:25] azivman3: mandatory
[15:25] azivman3: I am not talking APS
[15:25] azivman3: I am talking other setups
[15:25] azivman3: what do you think about their fuel system since you brought it up
[15:25] taurran2004: yes, but your reference to other setups is ALWAYS a comparison to the APS TT
[15:25] azivman3: ?
[15:25] azivman3: no comparison
[15:26] azivman3: You want some real info on the kit?
[15:26] taurran2004: whats that?
[15:26] azivman3: the turbos they use spool too quickly
[15:26] taurran2004: and?
[15:26] azivman3: the engine can have trouble consuming the amout of air they produce in the lower RPMS
[15:26] azivman3: results in compressor surge
[15:27] azivman3: VRT boys haven't seen it yet
[15:27] azivman3: because most are running cams
[15:27] azivman3: not as prone to show up with cams
[15:27] azivman3: also they might not be looking for it
[15:28] taurran2004: same can be said with the PE TT, but as you stated that can be compensated for
[15:28] azivman3: PE is garbage
[15:28] azivman3: not even in the same league as greddy or jwt
[15:28] taurran2004: instant power delivery is key ion the track
[15:28] azivman3: instant power is one thing
[15:28] taurran2004: not that it really matters for the average user who doesn't compete
[15:28] azivman3: too much abrupt power is another
[15:29] azivman3: the power comes on too abruptly with the JWT setup
[15:29] azivman3: resutls in excessive wheel spin
[15:29] azivman3: broken axels
[15:29] azivman3: trannies
[15:29] azivman3: etc
[15:29] taurran2004: well in time perhaps that will come to light
[15:22] azivman3: you want to discuss
[15:22] azivman3: get the ball rollin
[15:23] taurran2004: well, although I would love to hear about your APS TT and how great it is. I've already heard enough
[15:23] azivman3: you haven't heard much
[15:23] azivman3: lots more to discuss
[15:23] azivman3: what you think of the JWT TT setup?
[15:24] taurran2004: what do I think?
[15:24] taurran2004: I think its a great kit. Lots of potential
[15:24] azivman3: HP potential?
[15:24] taurran2004: although it might not include a mandatory fuel return system, like the all powerfull aps tt, its still nice
[15:24] taurran2004: not that I really care, I've already made my choice
[15:25] azivman3: mandatory
[15:25] azivman3: I am not talking APS
[15:25] azivman3: I am talking other setups
[15:25] azivman3: what do you think about their fuel system since you brought it up
[15:25] taurran2004: yes, but your reference to other setups is ALWAYS a comparison to the APS TT
[15:25] azivman3: ?
[15:25] azivman3: no comparison
[15:26] azivman3: You want some real info on the kit?
[15:26] taurran2004: whats that?
[15:26] azivman3: the turbos they use spool too quickly
[15:26] taurran2004: and?
[15:26] azivman3: the engine can have trouble consuming the amout of air they produce in the lower RPMS
[15:26] azivman3: results in compressor surge
[15:27] azivman3: VRT boys haven't seen it yet
[15:27] azivman3: because most are running cams
[15:27] azivman3: not as prone to show up with cams
[15:27] azivman3: also they might not be looking for it
[15:28] taurran2004: same can be said with the PE TT, but as you stated that can be compensated for
[15:28] azivman3: PE is garbage
[15:28] azivman3: not even in the same league as greddy or jwt
[15:28] taurran2004: instant power delivery is key ion the track
[15:28] azivman3: instant power is one thing
[15:28] taurran2004: not that it really matters for the average user who doesn't compete
[15:28] azivman3: too much abrupt power is another
[15:29] azivman3: the power comes on too abruptly with the JWT setup
[15:29] azivman3: resutls in excessive wheel spin
[15:29] azivman3: broken axels
[15:29] azivman3: trannies
[15:29] azivman3: etc
[15:29] taurran2004: well in time perhaps that will come to light
Hahaha.......
..Well, almost two years now (20,000+hard miles) with this JWT TT kit with lots of hard track days. No tranny, axel, drivetrain problems, and with a 305-315 mm tire in the back no real traction problems. The fuel system seems to be more than adequate for me and all of the VRT (happy) customers. So Hmmmmm, go figure.... 
Its cool though, sceptisism will always be there........... 
..Well, almost two years now (20,000+hard miles) with this JWT TT kit with lots of hard track days. No tranny, axel, drivetrain problems, and with a 305-315 mm tire in the back no real traction problems. The fuel system seems to be more than adequate for me and all of the VRT (happy) customers. So Hmmmmm, go figure.... Its cool though, sceptisism will always be there...........
Wow...Ziv should have made you sign an NDA. But now that this is out in the open, this statement is untrue:
[15:26] azivman3: the engine can have trouble consuming the amout of air they produce in the lower RPMS
[15:26] azivman3: results in compressor surge
An engine will not have trouble eating up the air produced by the turbos at low RPM. The valves are open longer, and the air will find its way into the cylinders without any problems. The result, is more cylinder pressure at low RPM, and gobs of mid range trq. Compression surge is not related to the turbo spooling quickly. The BOV will do its job, regardless of how quickly the turbo spools.
But now that this is out in the open, this statement is untrue:[15:26] azivman3: the engine can have trouble consuming the amout of air they produce in the lower RPMS
[15:26] azivman3: results in compressor surge
An engine will not have trouble eating up the air produced by the turbos at low RPM. The valves are open longer, and the air will find its way into the cylinders without any problems.
The result, is more cylinder pressure at low RPM, and gobs of mid range trq. Compression surge is not related to the turbo spooling quickly. The BOV will do its job, regardless of how quickly the turbo spools.
Last edited by Sharif@Forged; Feb 12, 2006 at 12:49 PM.
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Posts: 735
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From: Midwest
Originally Posted by Sharif@Forged
Wow...Ziv should have made you sign an NDA. But now that this is out in the open, this statement is untrue:
[15:26] azivman3: the engine can have trouble consuming the amout of air they produce in the lower RPMS
[15:26] azivman3: results in compressor surge
An engine will not have trouble eating up the air produced by the turbos at low RPM. The valves are open longer, and the air will find its way into the cylinders without any problems. The result, is more cylinder pressure at low RPM, and gobs of mid range trq. Compression surge is not related to the turbo spooling quickly. The BOV will do its job, regardless of how quickly the turbo spools.
But now that this is out in the open, this statement is untrue:[15:26] azivman3: the engine can have trouble consuming the amout of air they produce in the lower RPMS
[15:26] azivman3: results in compressor surge
An engine will not have trouble eating up the air produced by the turbos at low RPM. The valves are open longer, and the air will find its way into the cylinders without any problems.
The result, is more cylinder pressure at low RPM, and gobs of mid range trq. Compression surge is not related to the turbo spooling quickly. The BOV will do its job, regardless of how quickly the turbo spools.
I hate to add fuel to the flames but where on earth did you get this crap about surge from? Thats about as far off base as you can get. Surge happens for two reasons, air being trapped in the charge piping has no where to go when the throttle plate closes and as a result if there is not BOV it reverse direction and causes surge in the compressor. The second would be if you were operating a turbo at such limits that the air was not able to enter the engine even with the throttle plate full open and it caused reversion and surged the compressors. Neither of which are going to happen on this motor with those turbos... The whole assesment is as far off as it gets...
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wow LOLZ....he forgot more about FI than you know Craig. Which uh, I have to disagree with completely.
the JWT kit wasn't meant to be a max HP kit....you can call JWT and ask them that point blank. It was meant to act like a stock turbo system would on the Z, no noticeable lag and good solid power.
LOL@ zivman and his APS>everything attitude. Just because it doesn't use a standalone and a full fuel return system doesn't mean it HAS to.
btw, I'd be willing to put money on the fact that Clark at JWT could own you in most aspects of technical knowledge.........same with Jim.
the JWT kit wasn't meant to be a max HP kit....you can call JWT and ask them that point blank. It was meant to act like a stock turbo system would on the Z, no noticeable lag and good solid power.
LOL@ zivman and his APS>everything attitude. Just because it doesn't use a standalone and a full fuel return system doesn't mean it HAS to.
btw, I'd be willing to put money on the fact that Clark at JWT could own you in most aspects of technical knowledge.........same with Jim.
Last edited by chimmike; Feb 12, 2006 at 01:48 PM.
Seriously, its like APS has ziv brainwashed into thinking all kits have to be designed around needing a fuel return system. JWT designed their TT kit to be like a stock turbo out of the factory, which is also why they're trying to get their kit carb certified. To be carb certified in all states including the hardest one of them all "California" you have to keep all engine components stock so yes that even means stock fuel return system. I don't think its impossible to design a TT kit that does not need to upgrade the stock fuel return system if your design criteria is set right.
I prefer being called a "FI master" vs:
I think it is fair to say
taurran2004: well in time perhaps that will come to light
And Sharif I am aware of the info you posted:
Originally Posted by taurran
a fking tool...
taurran2004: well in time perhaps that will come to light
And Sharif I am aware of the info you posted:
Originally Posted by Sharif@Forged
An engine will not have trouble eating up the air produced by the turbos at low RPM. The valves are open longer, and the air will find its way into the cylinders without any problems. The result, is more cylinder pressure at low RPM, and gobs of mid range trq. Compression surge is not related to the turbo spooling quickly. The BOV will do its job, regardless of how quickly the turbo spools.
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Twin turbos that are very small/responsive can certainly suffer from compressor surge on the VQ engine at low rpm/partial throttle conditions - that is the engine cannot consume the amount of mass air flow that the turbos are producing in that particular throttle/rpm/engine load condition. 
Originally Posted by Sharif@Forged
The BOV will do its job, regardless of how quickly the turbo spools.
Originally Posted by BriGuyMax
Not true at all. In a compressor surge situation the BOV will not relieve pressure in the intake tract simply because it needs to see a sudden vacuum change (significant decrease in throttle) to activate.
Originally Posted by georgec
Twin turbos that are very small/responsive can certainly suffer from compressor surge on the VQ engine at low rpm/partial throttle conditions - that is the engine cannot consume the amount of mass air flow that the turbos are producing in that particular throttle/rpm/engine load condition.
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From: Melbourne
Originally Posted by failsafe306
What does compressor surge sound like?
Originally Posted by georgec
If you get the engine load and rpm conditions right up a small hill or on a load based dyno it sounds like air rythmically pulsing back through the air cleaners quietly from side to side. Not easy to describe best I can do is a subtle air noise from each air cleaner under light engine load.