Boosting my 95SC4 and some other projects
#257
Lexus Test Driver
iTrader: (3)
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Does the I/C piping get in the way of just running a filter to the side of the Compressor housing? If not, that would make a nice place for a custom airbox with a cool air feed from the fender. If not you could run it underneath the piping and cut a hole in the body for the intake pipe, then route it down to the vent in your front bumper. Just some ideas
Jon
Jon
#258
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Does the I/C piping get in the way of just running a filter to the side of the Compressor housing? If not, that would make a nice place for a custom airbox with a cool air feed from the fender. If not you could run it underneath the piping and cut a hole in the body for the intake pipe, then route it down to the vent in your front bumper. Just some ideas
Jon
Jon
But, see next few posts for more info.
KC
#259
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Went back to the dyno yesterday with mixed results.
Since last week, I put the intercooler back in and I fixed a leak at my bypass valve.
Made a couple of more hp and lost a couple ftlb's. But..for some reason, I was only averaging around 7.5 psi. I was doing 9.5 last week and I should be able to hit 10-12 at redline. The dyno operator said it looked like belt slip on the graph, the way the boost is wavy.
So I'm making the samish power with less boost, which is a good thing, I just need to figure out why I have less boost. Some of the psi loss is very likely due to the intercooler, but I wouldn't think I would loose 2psi. Removing the intake pipe and filter actually resulted in LESS boost. I was very surprised, both the dyno operator and the head tuner guy were scratching their heads as well.
The intercooler is staying BTW. With the ambient temp being pretty close to the same as it was on the first trip to the dyno, my intake temps were 60-65 degrees less yesterday than last week. After several runs, the intake temp was 95 degrees, compared to 160 degrees last week.
The thing the impresses me about the dyno numbers is the tourqe curve. Also, how smooth the power delivery is, I set the smoothing to 0 on this graph.
Dyno vid BTW.. http://youtube.com/watch?v=LJAxstJ_Sao
KC
Since last week, I put the intercooler back in and I fixed a leak at my bypass valve.
Made a couple of more hp and lost a couple ftlb's. But..for some reason, I was only averaging around 7.5 psi. I was doing 9.5 last week and I should be able to hit 10-12 at redline. The dyno operator said it looked like belt slip on the graph, the way the boost is wavy.
So I'm making the samish power with less boost, which is a good thing, I just need to figure out why I have less boost. Some of the psi loss is very likely due to the intercooler, but I wouldn't think I would loose 2psi. Removing the intake pipe and filter actually resulted in LESS boost. I was very surprised, both the dyno operator and the head tuner guy were scratching their heads as well.
The intercooler is staying BTW. With the ambient temp being pretty close to the same as it was on the first trip to the dyno, my intake temps were 60-65 degrees less yesterday than last week. After several runs, the intake temp was 95 degrees, compared to 160 degrees last week.
The thing the impresses me about the dyno numbers is the tourqe curve. Also, how smooth the power delivery is, I set the smoothing to 0 on this graph.
Dyno vid BTW.. http://youtube.com/watch?v=LJAxstJ_Sao
KC
Last edited by KC95SC400; 03-28-08 at 07:53 PM.
#260
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I've come up with, what I think, is a very clever and easy way to add some tension to the drive belt.
I took an L-bracket and drilled one of the existing holes a little bigger so it would fit a 12mm bolt through it. I then drilled and tapped another hole to fit a 12mm bolt.
I took an L-bracket and drilled one of the existing holes a little bigger so it would fit a 12mm bolt through it. I then drilled and tapped another hole to fit a 12mm bolt.
#262
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Then I removed one of the nuts from the drive belt tensioner, put the bracket on, and reinstalled the nut. There is a protrusion on the tensioner for the bolt to press against, it's somewhat visible in this pick through the open hole.
I have basically made a manual tensioner. Tension is adjusted by turning the bolt, the nut is there to lock the bolt in place once the desired tension is acheived.
This is an installed pic. Note the position of the arrows on the tensioner.
I have basically made a manual tensioner. Tension is adjusted by turning the bolt, the nut is there to lock the bolt in place once the desired tension is acheived.
This is an installed pic. Note the position of the arrows on the tensioner.
#263
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This is a pic of where the tensioner sat before the install. The difference is very dramatic. Before doing this, the belt would deflect 2-3 inches between the top idler pulley and the supercharger pulley. Now, it deflects about a half inch. The belt feels MUCH tighter.
This is my first attempt making this. It does need some improvement. I need to go to Home Depot and get a few more L-brackets to hack up.
KC
This is my first attempt making this. It does need some improvement. I need to go to Home Depot and get a few more L-brackets to hack up.
KC
#265
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I still think that I have more boost available, I've seen 12psi while street driving, even with the intercooler. Hopefully, belt tension is/was the issue. Looking at the pics, there is allot of shredded belt all over the place.
Keep in mind, much like different turbo setups, different size blowers are going to give you different results.
So far, knock on wood, the transmission is doing great. The car handles itself like a champ on the dyno. Street driving, I've even managed to loose traction a few times when downshifting. If the roads are even a little wet, I can really spin them when flooring it from low cruising speeds, when it downshifts to second or third.
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KC
#268
Lexus Champion
iTrader: (-1)
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Nice job on the new dyno run. The objective data from the dyno looks like it is working as an excellent tool to maximize your set up.
If you can see 9-10psi on the dyno with the IC, you are going to make numbers in the vicinty of the GS4 guys. Once you get your exhaust manifolds, you will be in that 350-390whp range where the GS4 guys are (with their V2 blowers on a VVT-i head).
If you can see 9-10psi on the dyno with the IC, you are going to make numbers in the vicinty of the GS4 guys. Once you get your exhaust manifolds, you will be in that 350-390whp range where the GS4 guys are (with their V2 blowers on a VVT-i head).
#269
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Quick update.
I've tried a few things and no matter what I do, I get about 9psi on the street. Still 2 more than I could get on the dyno.
So I'm keeping my current setup. Cold air intake to vortech to intercooler to bypass to throttle body.
The car is running fantastic!
Here's a new 0-60 vid. I clocked it at 4.6 seconds on 225 street tires launching a few hundre rpm's less than my stall speed!
http://youtube.com/watch?v=OUMgjV6ntgc
Thursday, I plan to head to the track! It's an eight mile track and every Thurday night is "test and tune" night. Any predictions? It would be awesome to run an 8 to 8.5 second pass. This would be about 12.5 to 13.2 in the quarter.
KC
I've tried a few things and no matter what I do, I get about 9psi on the street. Still 2 more than I could get on the dyno.
So I'm keeping my current setup. Cold air intake to vortech to intercooler to bypass to throttle body.
The car is running fantastic!
Here's a new 0-60 vid. I clocked it at 4.6 seconds on 225 street tires launching a few hundre rpm's less than my stall speed!
http://youtube.com/watch?v=OUMgjV6ntgc
Thursday, I plan to head to the track! It's an eight mile track and every Thurday night is "test and tune" night. Any predictions? It would be awesome to run an 8 to 8.5 second pass. This would be about 12.5 to 13.2 in the quarter.
KC
#270
Lexus Test Driver
iTrader: (3)
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Good to hear that you are keeping the I/C KC. I think Blizzy gas a good point here about the little things that you can forget about when you get boost happy. Sometimes it's not slapping on another blower that will be the best idea and yield the most potential (Economically speaking of course) at a given time. How your exhaust is design/flows can have a major impact on the torque, spool, hp, etc. What about lightweight pulleys, lightened one piece driveshaft, etc. Also, I bet you would see a nice improvement all over the RPM range with a good HKS ignition upgrade or something of the like. Just trying to throw out some of the little things that tend to get left behind and shouldn't. But then once you have done them your like, " why didnt I do these in the first place lol?"
Jon
Last edited by 2jzlex; 04-02-08 at 10:06 AM.