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+--- Thread: Is200 Kompressor (/showthread.php?tid=15729)
Is200 Kompressor - P.Nicolov - 06-02-2025
Lexuspat All the problems you listed above using a vacuum bypass valve I have never had.
The only time my car went into limp mode is when I blew my precats into the pipe blocking it.
On motorways which I do mostly it drives fine cruising at 70 80 without any issues at all.
I even tow caravans on it without any undue Acceleration, a few people have driven my car and same again it cruises at all speeds without major issues.
I'm sure the cable operated system is much better and is more like the tte kit in every way.
A great write up and explanation
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There are cases where the bypass spring has just the right hardness to avoid going into limp mode and the other issues aren't that noticable at low boost levels. IIRC you were running a 130mm pulley? Maybe combined these two factors are responsible for your experience. But I estimate I've talked with at least 30 guys who've had all of these issues. That's why the first batch of 20 valves we made sold out in 20 hours
TTE engineers really knew what they were doing and had some internal engineering information to make their bypass system. We didn't have this information nor their resources, so it took 6 months and A LOT of testing to perfect it. And all this because I didn't want to use a turbo :gay:Anyway, with the DIY stuff whatever works for someone may not work for others and anything is possible. The huge variety of builds is proof of that. I'm just offering my own view on things from my own experience
Is200 Kompressor - Lexuspat - 06-02-2025
This is very true
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Is200 Kompressor - Wayne - 06-02-2025
Mine was fine for a few weeks until I realised my throttle body bend had come loose and was pretty much being held in place by the strut brace! As soon as I stuck it back on properly I'm having the problems plamen mentioned. Before the issues (before my TB bend was on properly) Torque app was reckoning I was max boosting at 0.2 bar. I'm running the Merc 138mm pulley.
Is200 Kompressor - DannyStock - 12-02-2025
P.Nicolov.
A* for your reply!
Ideally throttle body in front of the s/c would be the ideal set up, but the IS's throttle body is no easy lump to move. I do have a spare sitting around atm, and one day getting some manifolds made up to relocate it would be an idea. But no small amount of work.
Very early on the benefits of a linear operation between bypass and TB were clear.
And yes, out of all, Toyota do know what they're doing lol
Part throttle boosting sailing off with no input from right foot.
This is why I have the "diesel valve" in-line pre-charger. It's not 100% perfect, but mimmicks the car's TB close enough, to restrict a little air at part throttle.
This is was an idea taken from the MX5 lot who use dual TB's alot in s/c applications.
The bypass valve i'm running is the "upgraded" one with the stiffer spring and "better sealing", I'm starting to think that the softer stock spring would be perhaps better suited for the IS application?
However I did experience some yo-yo-ing once that was a laugh going up a steep hill.
As it stands I'm going to test the operation of my black box. I have over looked this thus far due to the good reputation that P.Lindblom has with them & the lack of limp mode/EML.
Next move would be to possibly test operation of the MAP sensor itself (more for peace of mind).
Then consider a softer spring'd bypass?
Other people with bypass issues & similar symptoms, what was done to the bypass to resurrect the issue?
Is200 Kompressor - DannyStock - 12-02-2025
To your first reply in relation to s/c knowledge.
I did a lot of reading up back in the day in relation to supercharging the classic minis.
The arguements on their forums in regard to suck or blowthrough got quite heated at times lol.
On the A series engines, the dream was always a blow through set up.
This way mainly down to arguements over whether or not an Eaton M45 blower could stand to ingest fuel and carb icing due to relocation on the suck through set up (Vmax-scart being one of the first to release an official DIY kit).
But now on the IS and without the Toyota/TRD guru's still making the kits, we are at the mercy of trial and error, head scratching DIY research.
Without moving the throttle body to pre-charger.
A cable bypass is the only to get correct boosting characteristics really.
I'm certain borrowing some pushbike cables from work, small steel plate and cable nipples this could be achieved.
At this point i'd just like to make sure that I know what the issue is before I go spending money lol
Thanks alot for you input.
It is appreciated.
Danny.
Is200 Kompressor - DannyStock - 12-02-2025
And for those wanting to know still
I saw a max boost of 2.8psi (Y)
This is using the A/C driveland off the crank direct to s/c, works out at less boost/rpm than TTE so it makes sense lol
Is200 Kompressor - DannyStock - 13-02-2025
P.Lindblom you have PM (Y)
Is200 Kompressor - DannyStock - 22-02-2025
So after a late night brain wave...
I dropped the exhaust off at the manifold and a quick peek at bank 1 pre-cat confirmed this could be part of the problem.
It's absoloutely destroyed in there so plans to de-cat have been bumped to the top of the list.
No engine light or codes, likely down to the brainwave of the fact the exhaust is leaking at the bottom of the manifold, before the last O2 sensor (Y)
In the meantime, the bypass will be rigged by cable off the throttle
Is200 Kompressor - DannyStock - 22-02-2025
![[Image: 20170405_171046.jpg]](http://s261.photobucket.com/user/CANNYDOE/media/20170405_171046.jpg.html)
Om Nom Nom
Is200 Kompressor - Sparkystav - 19-03-2025
That doesn't look right lol
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