SC400TT Project Car
Lead Lap
Joined: Nov 2004
Posts: 421
Likes: 0
From: Illinois
Originally Posted by UpInTheLex
You can't boost a stock sc much over 6-7psi anyway
Especially if you want to boost the car much over 7psi. You need to buy pistons and rods too for good measure. And while you're there you should do all the head work, and valve job on all 32 valves and replace all 4 cams and on and on and on. The price tag just escalates in a hurry.
Especially if you want to boost the car much over 7psi. You need to buy pistons and rods too for good measure. And while you're there you should do all the head work, and valve job on all 32 valves and replace all 4 cams and on and on and on. The price tag just escalates in a hurry.
I ran my SC at 10-12 psi, and didn't have any problems until I had an injector fail. It burnt a piston, but the other 7 were fine, and the motor had 157,000 miles. tunning is very important at these boost levels with the stock pistons.
Also I boosted 18-19 PSI on a basically stock motor with only forged 8.5:1 pistons.
A new stock headgasket; stock rods, head/main/rod bolts&studs(original), and original 157,000 mile bearings were re used. I just pulled them out again after driving the car around with 18 PSI, and they still look great.
I did do a valve job, but it cost me $5.00 in lapping compound, and some of my time, well alot of my time.
the trans is what can't handle the power.
As far as the torque converter, it will help the car get off the line a little quicker, but slow low speed driving makes the car feel heavy. More pedal to get it moving. also worse gas mileage city driving
It has a lock up, so highway driving over 40MPH will be the same gas mileage.
Ryan, I found a couple old pictures of my down pipes.
I'll try and e-mail them to you. tonight.
Lexus Champion
Joined: Jan 2003
Posts: 1,621
Likes: 0
From: SGV
Bob is right.... It you have good timing and plenty supply of fuel, you can really crank up the boost. I ran (overboosted few times) to about 23 psi with stock pistons and rods. The key is tuning. The balance of Fuel, Ignition, Air and Timing (FIAT) is the key.
Lead Lap
Joined: Nov 2004
Posts: 421
Likes: 0
From: Illinois
By the way Ryan, I'm still waiting for you to beat my #'s
510RWHP, and 487RWTQ
13.1 @ 116MPH
How long are you going to let my SC 400 reign King?
And Chris and I are now changing to our 3rd set of turbos.
Divided T3 exhaust 57MM compressors
A little ball busting never hurt anyone. Did it?
510RWHP, and 487RWTQ
13.1 @ 116MPH
How long are you going to let my SC 400 reign King?
And Chris and I are now changing to our 3rd set of turbos.
Divided T3 exhaust 57MM compressors
A little ball busting never hurt anyone. Did it?
Last edited by rdm20fan; Jan 30, 2006 at 10:38 AM.
Originally Posted by rdm20fan
I disagree with what a stock 1UZ can handle.
I ran my SC at 10-12 psi, and didn't have any problems until I had an injector fail. It burnt a piston, but the other 7 were fine, and the motor had 157,000 miles. tunning is very important at these boost levels with the stock pistons.
Also I boosted 18-19 PSI on a basically stock motor with only forged 8.5:1 pistons.
A new stock headgasket; stock rods, head/main/rod bolts&studs(original), and original 157,000 mile bearings were re used. I just pulled them out again after driving the car around with 18 PSI, and they still look great.
I did do a valve job, but it cost me $5.00 in lapping compound, and some of my time, well alot of my time.
the trans is what can't handle the power.
As far as the torque converter, it will help the car get off the line a little quicker, but slow low speed driving makes the car feel heavy. More pedal to get it moving. also worse gas mileage city driving
It has a lock up, so highway driving over 40MPH will be the same gas mileage.
Ryan, I found a couple old pictures of my down pipes.
I'll try and e-mail them to you. tonight.
I ran my SC at 10-12 psi, and didn't have any problems until I had an injector fail. It burnt a piston, but the other 7 were fine, and the motor had 157,000 miles. tunning is very important at these boost levels with the stock pistons.
Also I boosted 18-19 PSI on a basically stock motor with only forged 8.5:1 pistons.
A new stock headgasket; stock rods, head/main/rod bolts&studs(original), and original 157,000 mile bearings were re used. I just pulled them out again after driving the car around with 18 PSI, and they still look great.
I did do a valve job, but it cost me $5.00 in lapping compound, and some of my time, well alot of my time.
the trans is what can't handle the power.
As far as the torque converter, it will help the car get off the line a little quicker, but slow low speed driving makes the car feel heavy. More pedal to get it moving. also worse gas mileage city driving
It has a lock up, so highway driving over 40MPH will be the same gas mileage.
Ryan, I found a couple old pictures of my down pipes.
I'll try and e-mail them to you. tonight.
Bob, I am looking forward to those downpipes...Thanks much, bro...
Ryan
Originally Posted by rdm20fan
By the way Ryan, I'm still waiting for you to beat my #'s
510RWHP, and 487RWTQ
13.1 @ 116MPH
How long are you going to let my SC 400 reign King?
And Chris and I are now changing to our 3rd set of turbos.
Divided T3 exhaust 57MM compressors
A little ball busting never hurt anyone. Did it?
510RWHP, and 487RWTQ
13.1 @ 116MPH
How long are you going to let my SC 400 reign King?
And Chris and I are now changing to our 3rd set of turbos.
Divided T3 exhaust 57MM compressors
A little ball busting never hurt anyone. Did it?
If I had someone as efficient as Chris, I would be beating your numbers right now... 
But good help has been hard to find in these here parts... 
Anyway, hail to the king...
And I will be boostin soon...If not, I will be shipping my car to Chicago to get it done!!!
Ryan
Lexus Champion
Joined: Jan 2003
Posts: 1,621
Likes: 0
From: SGV
Originally Posted by rdm20fan
510RWHP, and 487RWTQ
13.1 @ 116MPH
13.1 @ 116MPH
What type of dyno machine you did u use? I will be downgrading the 550 cc injectors to 460 cc and Luxury Motor Works will be doing the tuning and dynoing there. I will be running similar boost and cant wait to see the results.
Last edited by Lextreme; Jan 30, 2006 at 12:32 PM.
Well guys, went by and saw the passenger side downpipe today...Exciting!!!, it's almost done on that side. I took some pics and will post up later on today. BTW, we are going with 3" downpipes instead of 2.5" downpipes....
Looking good...I like his welding, he made very precise cuts for each piece of stainless...
Ryan 
Looking good...I like his welding, he made very precise cuts for each piece of stainless...
Ryan
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Lexus Fanatic
Joined: May 2001
Posts: 19,103
Likes: 2
From: Netherlands
Originally Posted by SC400T
Well guys, went by and saw the passenger side downpipe today...Exciting!!!, it's almost done on that side. I took some pics and will post up later on today. BTW, we are going with 3" downpipes instead of 2.5" downpipes....
Looking good...I like his welding, he made very precise cuts for each piece of stainless...
Ryan
Looking good...I like his welding, he made very precise cuts for each piece of stainless...
Ryan
OK Gang...I am tired...I fell asleep on the sofa, woke up a few minutes ago, and realized I had not uploaded these photos of the downpipe as it is being made. I snapped these about noon today, and I was told that by the end of the day he had finished the pipe going all the way down...I will snap some more pics tomorrow. Making more progress...There is Light at the end of the Tunnel... 
Ryan
Ryan
May I ask why you chose to do section welding instead of mandrel bending? I'm not a mechanical expert, but I would just assume that a bend pipe would be a more constant and smooth flow than the welds.
Either way, I'm excited for you, as is everyone else with a slow V8!
Either way, I'm excited for you, as is everyone else with a slow V8!
Pole Position
Joined: Mar 2004
Posts: 2,365
Likes: 29
From: Florida
Originally Posted by MongooseGA
May I ask why you chose to do section welding instead of mandrel bending? I'm not a mechanical expert, but I would just assume that a bend pipe would be a more constant and smooth flow than the welds.
Either way, I'm excited for you, as is everyone else with a slow V8!
Either way, I'm excited for you, as is everyone else with a slow V8!
The shown pipe is 3" and the radius of the bend is VERY small. An equal radius mandrel bent pipe would have a paper thin wall at the outer portion of the bend. Obviously for a downpipe you do not want this.
Section cuts like Ryan's guarantee uniform pipe wall thickness and strength. It takes much longer and is more labor intensive but you also get any (and/or even variable) radius which helps a TON in an application like this where space is at a premium. That pipe needs to contort into many funky angles while retaining strength.
Originally Posted by CleanSC
You can only mandrel bend down to a certain radius before you start to excessively weaken the pipe. Remember in mandrel bending, you stretch out the outer wall of the bend thus thinning it.
The shown pipe is 3" and the radius of the bend is VERY small. An equal radius mandrel bent pipe would have a paper thin wall at the outer portion of the bend. Obviously for a downpipe you do not want this.
Section cuts like Ryan's guarantee uniform pipe wall thickness and strength. It takes much longer and is more labor intensive but you also get any (and/or even variable) radius which helps a TON in an application like this where space is at a premium. That pipe needs to contort into many funky angles while retaining strength.
The shown pipe is 3" and the radius of the bend is VERY small. An equal radius mandrel bent pipe would have a paper thin wall at the outer portion of the bend. Obviously for a downpipe you do not want this.
Section cuts like Ryan's guarantee uniform pipe wall thickness and strength. It takes much longer and is more labor intensive but you also get any (and/or even variable) radius which helps a TON in an application like this where space is at a premium. That pipe needs to contort into many funky angles while retaining strength.