Turbo build

[sabretooth91]

Please forgive my "newbiness" on the subject.

I purchased a 1989 240sx coupe (KA24E) The guy I bought it from installed his own turbo and screwed up the timing on it. He bent valves and all sorts of badness. I brought it to a local garage. They really know their stuff about forced induction. They had two sick Supras on the lifts when I showed up and they are often at the drag strip in their free time.

I wanted to make sure my car was reliable when I started working on it, so I had them ship it out to get sleeved and bored. I said, "make sure I can put 20 lbs of boost and it won't blow up." I bought a manual boost controller because I knew I'd need it. Now, they have the engine in the car and it is making 9 lbs of boost. Obviously this is 1/2 of what I'm looking for. It is making 240hp at the wheels.

So, I'm not 100% confident that all the turbo parts are very good quality. I know the rubber elbows on the inter-cooler were crap because they cracked already. Can anyone suggest what parts I should look at replacing (and with what other parts) that will help me build more boost?

Maybe there is somewhere I can go to where I can build my own turbo based on the characteristics I want it to have. I know they're all very different. I'd like it to spool quickly over making monster boost, so I'd take a hit there if I have to.

Thanks for any help. I know this is a rather broad question, but I'm finding it difficult to find a place that really explains how turbos work, and which differences will impact what characteristics of how it works. I'm the kind of person who wants diagrams and pictures so I can know what role each part plays in the system so I can pick them to do what I want.

Thanks again.

[compactfean]

http://www.turbobygarrett.com/turbobyga ... tech_basic
This should have more than enough info to start. Make sure you fully understand how to place yourself on the compressor maps and maybe even call tech support to help narrow down your choices.

[elitefew22197]

Also, we have an entire forum dedicated to KA-T setups. They have helpful information like
ka-t-components-required-for-this-amoun ... 83590.html

[sabretooth91]

Also, we have an entire forum dedicated to KA-T setups. They have helpful information like
ka-t-components-required-for-this-amoun ... 83590.html

For the win. Thanks! I appreciate that!

[elitefew22197]

No worries man, good luck with the build

[sabretooth91]

Thanks. After looking around, it looks like 9lbs of boost and 240 hp before tuning isn't too shabby.

[elitefew22197]

Not bad at all, especially for SOHC

[sabretooth91]

Yeah it's up to 12 lbs of boost and 275hp to the wheels. I have a LSD sitting at home ready to go in too. They said if I get larger injectors, I can push mroe boost. I'll enjoy it for now, and put in the injectors over the winder while I do body work to it. Thanks for the help. Those links were great.

[elitefew22197]

275 at the wheels is tits man, that power should keep you satisfied until you can get bigger injectors. What injectors are you running currently? If Iirc 550cc injectors are maxing out around 300whp.

[sabretooth91]

Yeah, I have 550cc injectors. I was recommended to get 83 lb injectors, which I believe equals out to 871.5cc. That looks a lot bigger to me!

The injectors are forcing me to max out at 11.5-12 lbs of boost. I was hoping to get around 20 lbs. I have a couple other electrical things I want to upgrade as well. But, I'll just get used to it like this for now, and upgrade over the winter, while its garaged. This clutch is something else. Very "grabby", and right at the top of letting the clutch our. I feel like a rookie stick-driver all over again!

Still couldn't be happier though.

[sabretooth91]

PS. I double-checked. Looks like they guy who had it before me swapped in the KA24DE DOHC. So....

[biggie]

Hope the shop knows what they are doing, seems you aren't too sure on what all was done to the engine. You really would want to know before add parts/more boost.

[elitefew22197]

Yeah, I have 550cc injectors. I was recommended to get 83 lb injectors, which I believe equals out to 871.5cc. That looks a lot bigger to me!

The injectors are forcing me to max out at 11.5-12 lbs of boost. I was hoping to get around 20 lbs. I have a couple other electrical things I want to upgrade as well. But, I'll just get used to it like this for now, and upgrade over the winter, while its garaged. This clutch is something else. Very "grabby", and right at the top of letting the clutch our. I feel like a rookie stick-driver all over again!

Still couldn't be happier though.

Haha, my clutch is heavy as fyuck, makes me feel the same way! If you plan on running more boost id look into some kind of boost control. Also was the shop able to give you any insight on what kind of engine work/mods? And what kind of electrical things are you upgrading?

[sabretooth91]

I have a manual boost controller and a boost retard. I'll be upgrading the ECU and the Engine Management.

Strangest thing happened the other day. The car has been running fine since I got it. Then, after I had been driving for ~an hour, whenever I pushed it hard the car would slip out of gear when it really started putting down the power (4,000 rpms). The rps would skyrocket really quickly, but it wouldn't be making it to the wheels. I had my foot completely off the clutch. This would happen shifting into gear at high RPMs and it would slip out, and if I start at low RPMs and ramp it up.

Yesterday, I took it out again to try it, and no issue. But I hadn't been driving it for an hour. (so at least it doesn't seem like I damaged anything.)

The clutch only grabs when I let it all the way out. so maybe when it gets warm, its just not grabbing tight enough. I believe it is a cable clutch, so is this just something that can be tweaked so it is engaged before letting the pedal all the way up?

[elitefew22197]

I have a manual boost controller and a boost retard. I'll be upgrading the ECU and the Engine Management.

Strangest thing happened the other day. The car has been running fine since I got it. Then, after I had been driving for ~an hour, whenever I pushed it hard the car would slip out of gear when it really started putting down the power (4,000 rpms). The rps would skyrocket really quickly, but it wouldn't be making it to the wheels. I had my foot completely off the clutch. This would happen shifting into gear at high RPMs and it would slip out, and if I start at low RPMs and ramp it up.

Yesterday, I took it out again to try it, and no issue. But I hadn't been driving it for an hour. (so at least it doesn't seem like I damaged anything.)

The clutch only grabs when I let it all the way out. so maybe when it gets warm, its just not grabbing tight enough. I believe it is a cable clutch, so is this just something that can be tweaked so it is engaged before letting the pedal all the way up?

That is strange, if you hadn't upgraded the clutch from stock I would say your clutch was slipping b/c of the additional power. Maybe your slave cylinder is going out or something? Could someone with a little more knowledge on transmissions chime in here?

[compactfean]

You're trans is hydro but you can adjust the rod on the clutch master where it connects to the pedal to engage sooner. If your slave cylinder gets stuck in any given spot it can make the throw out bearing nit disengage all the way. Id get someone to press on the clutch pedal and watch the slave cylinder and sere if it appears to be working properly.

[sabretooth91]

You're trans is hydro but you can adjust the rod on the clutch master where it connects to the pedal to engage sooner. If your slave cylinder gets stuck in any given spot it can make the throw out bearing nit disengage all the way. Id get someone to press on the clutch pedal and watch the slave cylinder and sere if it appears to be working properly.

Will do. Thanks!