A&Q about 350Z
Q:
I'm pretty new to forced induction, so bare with me on this one...
I have a 1.8 mk1 gti and i'm building a new block for it, was thinking rebuilding it, adding a mild cam (260-270), do a bit of porting (already started this), up the compression to about 11:1, lighten the flywheel (and maybe rods)... But now i have the opportunity of buying the whole turbo and k-jet setup off a 1982 saab 900 turbo (2.0 8v) for little money... so now i'm considering maybe adding FI into the mix
I think this is a T3... would it work on a 1.8gti engine ?
I think i can arrange the fueling since i would have all the saab k-jet parts, a flange can be made to fit it to a 1.6TD exhaust manifold i think, i can have someone make up a spacer plate to lower CR, but what else do i need to take into account ?
How would i do the ignition part ? I heard about using the vacuum canister off a audi k-jet turbo so it will retard ignition while on boost... Anyone using this method ?
I'm not looking for mega-bhp: anything over 160bhp would be ok (since it's a mk1 i use on the road)... i would however not like to have much turbo lag (but i don't think this will be the case with a turbo like this) or -and this is maybe more likely- end up with an engine that's dead after 5000rpm (opinions?)...
It should still make peak hp around 6000rpm (or maybe a little higher)... Is this turbo appropriate for reaching my goal ?
And what CR and boost pressure would be ideal ?
Thanks
A:
I'm pretty new to forced induction, so bare with me on this one...
I have a 1.8 mk1 gti and i'm building a new block for it, was thinking rebuilding it, adding a mild cam (260-270), do a bit of porting (already started this), up the compression to about 11:1, lighten the flywheel (and maybe rods)... But now i have the opportunity of buying the whole turbo and k-jet setup off a 1982 saab 900 turbo (2.0 8v) for little money... so now i'm considering maybe adding FI into the mix
I think this is a T3... would it work on a 1.8gti engine ?
I think i can arrange the fueling since i would have all the saab k-jet parts, a flange can be made to fit it to a 1.6TD exhaust manifold i think, i can have someone make up a spacer plate to lower CR, but what else do i need to take into account ?
How would i do the ignition part ? I heard about using the vacuum canister off a audi k-jet turbo so it will retard ignition while on boost... Anyone using this method ?
I'm not looking for mega-bhp: anything over 160bhp would be ok (since it's a mk1 i use on the road)... i would however not like to have much turbo lag (but i don't think this will be the case with a turbo like this) or -and this is maybe more likely- end up with an engine that's dead after 5000rpm (opinions?)...
It should still make peak hp around 6000rpm (or maybe a little higher)... Is this turbo appropriate for reaching my goal ?
And what CR and boost pressure would be ideal ?
Thanks
As I would say to anybody attempting this. Sort out your hardware and plan what you want to achieve well.
Leave control of fuel and ignition to a good stand alone. It will be cheaper and neater in the long run. Try a Megasquirt EMS with spark-extra this will use all PB engine code sensors and dizzy and does not need an AFM. It will alow lots of adjustment of your fuel and spark and will always be there incase the spead bug bites again! For your output (160 BHP) you can use G60 injectors on the PB injector rail. A good CR is 9:1. Boost pressure is dependant on turbo CFM and engine VE at revs. A T3 saab unit should, on a good exhaust manifold, allow you to have a 5500rpm HP peak with 3000rpm torque peak off the top of my head. 7 psi should be more than enough to have a smooth and torquey 8v providing you get all the rest of hardware right.
If you need any more info on megasquirt feel free to pm me.
A:
I know, megasquirt is, logically speaking, definately the best answer... but i really want to do this on k-jet, otherwise i'd rather leave it and just build the mild N/A engine...
Do you think it would be out of breath at around 5500rpm ? That's just a bit too early, or could i let the wastgate open later (around 6000), would it be up for that ? The turbo would be off a 2.0 8v, so wouldn't the revs for max boost be somewhat higher on a 1.8 ?
I don't really know the exact spec of this turbo, but i already found out it's most likely an oil-cooled Garrett TB03...
A:
I know, megasquirt is, logically speaking, definately the best answer... but i really want to do this on k-jet, otherwise i'd rather leave it and just build the mild N/A engine...
Yes But a "Mild N/A" will never have the torque response as a blown motor no matter how hard you rev the N/A engine.
You may be able to use Saab OEM CIS bits to meter the fuel correctish but you attempts of mappping the engine for response (spark) off boost/low revs and on boost low rev and high revs will be very compromised/crude with out some sort of 3D system. I am sure you can get something to work but what happens when the desire for 160bhp turns to 210Bhp? How much mechanical compromising are you willing do then. And trust me you will get there fast!
Do you think it would be out of breath at around 5500rpm ? That's just a bit too early, or could i let the wastgate open later (around 6000), would it be up for that ? The turbo would be off a 2.0 8v, so wouldn't the revs for max boost be somewhat higher on a 1.8 ?
As said before, Boost pressure is a relationship between the max air supplied efficiently by the turbo and the air required by the engine due to volumetric efficiency. I would imagine that the lil saab T3 unit will spool up faster on a 2.0 than a 1.8 due to greater exhaust pluses. But max hp will really be down to how the engine performed as a N/A. The turbo just helps to amplify this. On an 8v with a 6K rev limit torque in lbft tends to be greater than power in BHP. Ideally the gaps in gear ratios will increase to make use of the "shove you area".
What I have noticed is that normally the turbo, if well sized, can keep the VE of the engine remaining high a lil longer than if it were N/A. Cam timing and valve lift will take its toll to this and reduce VE all other things being equal.
I don't really know the exact spec of this turbo, but i already found out it's most likely an oil-cooled Garrett TB03...
ON the CHRA of the saab turbo there will be a number, TB03********. Get this and PM me I will try to get the compressor maps and simulate how this may work on a 1984 cc VW bottom end with sohc. That way you can have and idea but is just an idea.[/QUOTE]
A:
Thanks for all the good info, I will be looking into the saab's turbo number...
A:
If anyone knows other/better turbo k-jet setups that can be had off older cars for a reasonable price, feel free to add info, because the saab deal might not be completed...
I'm also looking into porsche the 924turbo system... better/worse: opinions ?
A:
If anyone knows other/better turbo k-jet setups that can be had off older cars for a reasonable price, feel free to add info, because the saab deal might not be completed...
I'm also looking into porsche the 924turbo system... better/worse: opinions ?
Hi, just got back into forum after forgetting my password....silly me, Now this k-jet set you want to accomplish will be easy to do , but also the quickest why to BLOW YOUR engine up ,as toyotec says its not the correct set up to manage turbo. k-jet is not design to really run turbo.....take it from me i had one and still do, It had blown up just when i needed that little more power racing a proper G60 rally over the 100 mph..... well way over. i would not convince anyone that k-jet can support turbo it can't , it just can't produce enough fuel through the entire rev range, has no device really to detect boost ....i can give you a list of faults that you will encounter but that will take up two to three columns.
all i had was just 159bhp and 165 ILbft it was quick, very quick so quick that it blew up VERY QUICK . Now i have built a proper motor 2.L 8v turbo with mega sq....making about 260bhp with more to come.
A:
audi quattro's use kjet for turbo engine. WR and MB engine along with many other variants, the injection systems on the audi is very simple and there is loads of them being broken up at the minute
A:
Now this k-jet set you want to accomplish will be easy to do , but also the quickest why to BLOW YOUR engine up ,as toyotec says its not the correct set up to manage turbo. k-jet is not design to really run turbo.....take it from me i had one and still do, It had blown up just when i needed that little more power racing a proper G60 rally over the 100 mph..... well way over. i would not convince anyone that k-jet can support turbo it can't , it just can't produce enough fuel through the entire rev range, has no device really to detect boost ....i can give you a list of faults that you will encounter but that will take up two to three columns.
Sorry to say this; but i think that's just bull****...
There are many factory k-jet turbo's: volvo, saab, audi, porsche, ... Would they use this system if it wasn't suited for the job ? Just because it's an older system doesn't mean it's useless nowadays... i does take a bit more dedication perhaps...
I guess you ran a k-jet that wasn't designed for a turbo application... (or you didn't have anything retarding ignition while on boost perhaps?)
You say they're not boost sensitive ? wrong: the WUR's of turbo k-jet systems are...
Oh and feel free to give your list of faults... I know k-jet can't be as accurate in giving the amount of fuel needed in a certain point in the rev range, when compared to megasquirt, but that doesn't mean it can't be done... In the old days there were turbo's on engines with carbs and point-ignition... It doesn't blow to pieces unless you are unaware of what is going on in the combustion chamber... and that counts for any engine: wether it's an old k-jet or a state of the art stand-alone managed engine...
(Just so you know i have nothing against MS, it's a fantastic system, i will very likely be using it in the future on some other engine)
A:
i know many people that use the kjet system to acheive 300 bhp, so why not, it may be old skool injection but if it works!!!
A:
[quote=82erGTIThere are many factory k-jet turbo's: volvo, saab, audi, porsche, .[/QUOTE]
Or were some of those KE-jet? Cant rem without looking it up.
A:
Or were some of those KE-jet? Cant rem without looking it up.
Both really... Earlier models use basic k-jet with WUR, later on some started using ke-jet...
A:
rather than modify a VAG block to low comp how about tracking down a porsche 924 turbo lump? you could just swap the whole lot ( engine, loom, ecu, fuelling etc) into your motor.
A:
how about tracking down a porsche 924 turbo lump?
that should be time consuming
they were rare at the time, let alone now
A:
but if one were to appear suppose, how much hard work would that entail?
A:
I probably will be getting it off that saab... for some reason people want way to much money just because it something's off a porsche (eventhough there's not much "porsche" about it and not that different form say the saab setup)
rather than modify a VAG block to low comp how about tracking down a porsche 924 turbo lump? you could just swap the whole lot ( engine, loom, ecu, fuelling etc) into your motor.
Do you mean use the 924 block... that wouldn't fit i think... would definatly be a lot more work than using a VW block... (G60 perhaps... or something else with oil squirters and use a spacer plate)
A:
Now this k-jet set you want to accomplish will be easy to do , but also the quickest why to BLOW YOUR engine up ,as toyotec says its not the correct set up to manage turbo. k-jet is not design to really run turbo.....take it from me i had one and still do, It had blown up just when i needed that little more power racing a proper G60 rally over the 100 mph..... well way over. i would not convince anyone that k-jet can support turbo it can't , it just can't produce enough fuel through the entire rev range, has no device really to detect boost ....i can give you a list of faults that you will encounter but that will take up two to three columns.
Sorry to say this; but i think that's just bull****...
There are many factory k-jet turbo's: volvo, saab, audi, porsche, ... Would they use this system if it wasn't suited for the job ? Just because it's an older system doesn't mean it's useless nowadays... i does take a bit more dedication perhaps...
I guess you ran a k-jet that wasn't designed for a turbo application... (or you didn't have anything retarding ignition while on boost perhaps?)
You say they're not boost sensitive ? wrong: the WUR's of turbo k-jet systems are...
Oh and feel free to give your list of faults... I know k-jet can't be as accurate in giving the amount of fuel needed in a certain point in the rev range, when compared to megasquirt, but that doesn't mean it can't be done... In the old days there were turbo's on engines with carbs and point-ignition... It doesn't blow to pieces unless you are unaware of what is going on in the combustion chamber... and that counts for any engine: wether it's an old k-jet or a state of the art stand-alone managed engine...
(Just so you know i have nothing against MS, it's a fantastic system, i will very likely be using it in the future on some other engine)
A:
Hmm....for someone who claims they know very little in force induction, you have a lot to say, if you think that this primitive kit suits your conversion well all i can say is go for it and good luck....I can't see why anyone would want to build a turbo car this century with a fuel system that is basically older than your car. For your info i had the turbo technics conversion, what you don't understand is YES k-jet did have turbo connected to them but they was not reliable....these cars you mention, OK they worked but how many of them are around today and just a handful and the people that drive them most properly never gone over 80 MPH or maintain high speed for very long . Try to run more boost through these cars and you'll run into issues , what you need to do is put a A/F gauge on one of these k-jet turbos and see what you get .
A:
Sorry gerry but i know many quattro owners that have modified the kjet system and get excellent results. just because its old hat doesnt mean it cant/wont work.
have you ever been in a UR audi quattro on fulll boost, my brother in law has an MB engined one in std form and it pulls like a train. I agree it may not be the most environmentally friendly car but why start modding engines if thats you concern.
More Boost on any car will cause problems more boost = more wear and tear, but sensibley mangaed can be great
Just build what you want to build there will be people that can help along the way im sure.
at least you are trying something different. i applaud thee
A:
Yesterday i went and got the turbo en k-jet system off the saab 900 (it was also a '82, like my gti)
can't see why anyone would want to build a turbo car this century with a fuel system that is basically older than your car.
-It's as old, not older...
-The gti originally has k-jet and so did the turbo kits that were designed for it in that era (Schrick, Callaway, ...)
-Without k-jet it will become a lot more obvious that it is not a standard engine (and engine tuning isn't actually allowed over here)
-I agree it's not THE BEST way of fuelling a forced induction engine, but it will be the cheapest and fairly effective when some inginuity is applied and seeing as i'm not looking for mega-bhp figures...
-i like the idea of making this older system work with less cost but perhaps some more creative solutions and lots of tinkering
Sorry if i reacted a bit edgy last post, it's just annoying if you start a k-jet turbo thread somwhere, first thing people do is try and talk me out of using k-jet, well just consider it a given that i WILL be working with k-jet...
You are totally right it is a comprimised situation, but i am aware of this and since i'm not looking to extract the maximum, i think this will work... Oh and i was planning on hiring a wideband lambda so i can adjust fueling to some extent (allen screw in the saab turbo WUR) and make up some sort of knock detection system, even if it's only going to a led in the dash for instance... I do want to know what's going on inside the engine, i'm not going to run it "blindly" and just maximaze boost etc only to find that oddly enough it blew up after a few days
Also yesterday i saw this was a saab with APC-system wich controls boost, basiscally by running a solenoid valve that bleeds of pressure going toward the actuator for the wastegate... I'm thing of reusing this solenoid in some way so i can control max boost to only be allowed under certain optimal circumstances...
So i'm not trying to discredit your opinions (people that run standalones etc), but it would be better if you could think along constructively with this k-jet turbo setup and share your experience in making THIS work, no?