JIBBBY

Dawg - I have not done the sea foaming yet because I don't want to upset the neighbors from the mushroom cloud of smoke that will be created......Will do it soon though.......Did you get alot of smoke when you seafoamed? Oh, and change the plugs and you may then see a difference as you said....Let me know how it goes...... Dawg - Good luck with your exhaust...Post up a picture or two afterwards...Dawg you need to go with 2.50 inch non mandrel exhaust piping on the lexus 400's....That is the best flowing fit for your SC...3" piping won't flow as good... 2.25" mandrell exhaust piping is proven to be the absolute best fitting and flowing exhaust for the 400 engines...Expensive too... I argued with the guys over this for awhile until I was proven wrong...Something about the way the exhaust crosses and circulates threw that 400's smaller sized piping makes it flow faster.....Not the case on many other cars with straight pipes, bigger is usually better, not so here........The muffler shop may try to talk you into larger piping but don't do it...trust me... I would either get - 2.50" inch non mandrel exhaust piping...That is the tubing that is bent customly to fit into your exhaust system.. Usually right their at the exhaust shop...The only problem with that is at the bends the piping size is reduced..At each bend exhaust flow will be restrictied just a bit...Not so with Mandrell piping... or the best and more expensive is - 2.25" inch mandrell piping - That is exhaust tubing that is bent but at the bend the size is not reduced..It's a true 2.25" inch exhaust pipings through out....Muffler shops can't make you those in house...... Again don't get the 3" inch exhaust piping on your SC4 unless you have future plans to either turbo or supercharge...With a turbo or supercharger the exhaust piping can be bigger because more air and exhaust will be pushed thru so larger piping is ok...Hope this helps..

Thanks for the perks but as far as moderating goes...I must pass, as it is not my thing..., Besides, SK perfornance does a fine job on this site and also probably knows a little more then me about these SC cars....Sk was around when I first started modify'ing these cars which is now going on for about 3 years now... I remember asking him questions years back and getting quality answers...

Hey fellas glad I can offer you guys some direction... Update - I was just about to purchase a used Supra Auto TT tranny the ohter day to swap into my SC400 but recently found out from LEXTREME.com that a torque converter alteration would be needed..That means I would have had to dump my Dragon Torque Converter...Well that's not going to happen so I have decided to go with a company called Boost Logic (boostlogic.com) which takes your strock tranny and rebuilds it for $1800 to support much more horsepower, etc.. It's been proven to be a good mod in regards to tranny upgrades....I will be sending mine in a few months...The great thing about this is that no alteraations will be needed just send it out and get it back stronger...The newly re-built tranny's supports around 500-600whp but unfornatunately still perform like stock. Still no more tranny hinderance with that...Just for the record my stock tranny is still holding up after two years of beating on it almost daily...These cars are really built very well indeed...... Also, I am glad that there is interest with this thread.. When I first wrote it I didn't think one person would read it on this forum...Just wanted to let you guys know what you are missing out on.....These SC400's really do have some potential and with just a few mods you can start to get these slugs moving and looking sharp too..As I said before these Lexus were designed to please the older folk so the perfornance is restricted at stock...The performance is their but just needs to be brought out.....I felt it was necessary to share...Good luck with all your mods everyone... Will post my local shop hookups shortly....

Wow you read this whole thread...You must have had some time to kill...Anyway, most of the work to my SC4 I did myself...However, exhaust mods I used Mr. Kool Muffler shop in South Central LA...They are cheap fast and good...Not the best of areas but the shop is safe and they are nice guys.. I am a white guy and had no problems, been their many times.. Example: A new Lexus radiator installed $150, they did my magnaflow center cat for $150 and had one in stock...Muffler installs $50 ( I brought them the mufflers).....I bought most of my mod exhaust stuff off of EBay and had them install everything...I am in the middle of a move so my paper work is buried in boxes...I will get back too you...Get the parts and I will tell you where to get them installed....Paint, radiator, exhaust, interior, I got the hook ups....

I have never heard of re-coning the speakers, cool......I didn't think that was possible....I agree if you plan to stick with the stock system and stock AMP you may choose to re-cone instead of replace..... However, a mild kicker Sub woofer to match the stock amp power output will perform just as nice as the stock sub if not better...I am living proof of that...I first just changed my sub woofer only while using the stock AMP...Sounded perfect and there was no sub woofer distortion at full volume....I then decided for $200 more I would double the power output with a new Kicker KX amp. THat price included installation......A year later my system still rocks, and sounds way better then stock......

You need to remove and dump the stock amp...Go for either a KX350 or KX450 kicker amp...That will be twice the volume level output with good sound then stock......All front stock speakers can handle it, the rears need to be changed out...If you are happy with the stock amp then just replace just the sub to like a 200w kicker 10" sub and be done with it..I wanted more base so I went with the after market amp...I am happy with it...

Glad I can be of help.... You will experience nice gains with each exhaust mod you do...Mufflers yuou notice more power immediately, Center cat the same but not as dramatic...Headers and the two cat deletion will make you smile for sure....Good luck Dawg....

Ok let's see if I can answer these questions - Sorry I don't have any pictures of the back of my car...Need to shoot some...My hardrive fried and I lost all my pic's...Most upsetting.. Straight thru mufflers are circular and probably don't look as good as the ovals...They are the best performing mufflers out of the bunch...Megan N1 mufflers is what I have.... The Magnaflow 2 into 1 center main catalytic converter I got at a local muffler shop for like $100...Installed for $50.... The resonators are also circular and mount behind the mufflers right after the bend in the pipes...Any striaght portion of the exhaust is where the high flowing resonators can be mounted..It really doesn't matter... You don't have to replace the stock piping, but if you want better flow 2 1/2 non mandrell piping or 2 1/4 inch expensive mandrell piping will flow just a little better then the smaller stock piping..Not a big difference as the mufflers, all three cats and the stock headers are what really restricts the exhaust flow...Remember the easier the exhaust gases can travel thru your exhaust system the more power and performance you will get.... Headers - scroll back up this thread and I think I described three header options available for the SC4's.... You will lose a tiny bit on lowend toque and I probably wouldn't consider the header upgrade until the torque converter is upgraded first...While you do lose a little at lowend you however gain a ton at topend...Torque converter first then headers would be my advise...Headers and deletion of those two little cats really makes a huge difference with exhaust flow.....Get the true bolt on headers when you are ready and not the S&S SC400 Headers like I have...There is some custom expensive fitting needed with the S&S Headers.. Hope that clears things up for you a bit...

Yes it is an air free 10" Kicker sub woofer, and yes the bass is rediculous if you adjust the amp setting for for bass...Twice the sub sound as stock... Kicker subs are one of the best....

Jibbby, I think you're right about sticking with the Magnaflow...I like the stock, oval shape better. OK, so this should be a good plan: 1. Replace mufflers....Where did you get the Megan's? Where should I get them? Cost? 2. Add resonators...what brand should I look into to? Where to get them? Cost? 3. Replace main cat & Y pipes with magnaflow 2-in-1 cat w/Y design....where should I get this? Cost? 4. Should I replace all of the piping between the cat and the mufflers? What diameter? Cost? Ebay has good deals....Straight thru mufflers are cheap and perform the best...However they are not oval like stock...Magna flows and Blitz Nur are oval... Megans N1's cost me $100 for both off of Ebay...$50 for two high flowing resonators... Magna flow center cat 2 into 1 maybe run you $150... Then if you really want to get serious delete the two little cats and get headers.... That covers the entire exhaust pretty much.. 2.25 inch mandrell rear exhaust piping is also the best......Now if you want to get real nasty, some have dared to put 3" straight pipes and Headers, no cats, etc....Remember the best exhaust is no exhaust, but there is special mods that need to be done to accomadate 3" straight exhaust on these SC's..The cross over in the exhaust piping is very important on our SC's....

Latest project - Ok My SC400 is dishing out around 300rwhp and or around 400hp now....The stock auto tranny labors at times and is basically not performing to the engines potential... the shifts are too long at times, kick down shifting times when rolling takes forever, and the bottom line is that the stock SC400 trannies are not built with performance in mind..Which is understandable, they are built for luxury......I have found two cost effective options for upgrading the Sc400 transmissions to perform to todays sportcar standards while still keeping it a automatic and not a manual..... !) Boost logic Transmissions (boostlogic.com) - This is a Lexus Tranny shop located in Austin, Texas and they build up your stock SC4 tranny to hold heaps of power for around $1800..They do the shipping thing too...Probably the best proven deal around while still keeping your original stock tranny.. Shifting is still pretty much the same, this company has been pumping out these built 400 tranny's for years now..... Again $1800 is the cost.. 2) 1993-1998 Supra Twin Turbo Automatic transmissions # (A341E) - This swap is very doable without much if any modifications. The bolt patterns and fitment are identical between the sc400's and the 93-98 Supra's ....With the ability to handle 500whp the Supra TT auto tranny is simply better and built stronger then the SC400 tranny's.. They have a longer first gear, better and more timely shifting, etc.. Luxury is still possible too... I just found a used 95 Supra TT Automatic tranny with 70,000 miles at a local junk yard and I may pick it up for $1000 in the next few days.....As you know those Stock Supra's were rated at around 300whp and do what 0-60mph in the mid 4 second range...They shift nicely too... In case you didn't know the Supra and SC lexus share identical subframes and most parts are interchangeable between the two cars...I currently am now running the Supra TT Limited Slip Differential and that just bolted right in, no mods needed......So I am hoping for around $1000 I can get a very nice and effective transmission upgrade with this... Wish me luck...Just need to aquire a little more info about the electical tranny reads and one seperate transmission pressure line and I am set to go.... Thought I would share this info just for the heck of it....

Dawg - THe blitz Nur Spec is an excellent choice and expensive one too...That will take care of your rear exhaust section...If you can afford that then get it...Secondly look into the cheaper magnaflow setup... Kicker sub and KX kicker amp is a good choice for upgrading the sound system from stock.....The front speakers do not need changing...Just the stock sub and two rear speakers next to the sub...I got everything off of Ebay...10" 600w kicker sub , Two 5" 300w inch Sony Ipod speakers and the 2 channel KX250 amp...It's almost twice as loud as the stock setup...However, I wish I would have gotten the Kicker KX350 Amp instead...I am just slightly underpowered for my taste.....My system rocks though.... The stock amp is rated at 300w but the KX250 amp is more like 500w... NKG plugs and wires are also a good choice....

My pleasure Moony, that is what these forums are for, and that is to share good information to help out everyone who reads it...

OK, well torque is not just created it is transfered more or less....With the dragon torque converter the stall rate in the torque converter becomes more aggressive, there is less slipage and more lock up...The car really bolts off the line and becomes very fun to drive...You will pretty much hang with most sports car 0-30 mphand the feel is a complete opposite of how the stock torque converter feels...At stock you practically have to get out of the car and push to get it moving from a dead stop...The takeoffs can still be smoothe and slow too...Driveability and luxury does not suffer.. Ok what you lose at top end is 20% percent or so would be my best guess...So like 60mph-100mph it won't quite have that kick power with the ECT button on that you have now...The decrease is not that big of a deal but you will notice it slightly, but the gains at low end are night and day from stock...I would have to say it's the best mod you can do for the Lexus car in my opinion...The best thing about the D.T.C. is that you can still maintain the luxury feel of the vehicle, you won't jerk your neck and head back at launch unless you want too... Now, too gain back what is lost from this mod I would say you will need to change out your rear exhaust section to highflow. Like good conservative magnaflow oval mufflers and a magnaflow 2 into 1 cat...That will get you back to normal but you will really motor up to 30 or 40 mph after that....I smiled for weeks after that TC upgrade and still enjoy it after 2 years...I kid you not...It is not cheap but I would say it should be top priority if you want to bring out some fun spunk out of the car... I mention the Magnaflow exhaust because it resembles stock, has great flow and will not break the bank....Also won't rock the neighboorhood with excessive exhaust noise... Slap two high flow resonators on with the magnaflows and at it will be as quiet as stock and you should gain as much as 20-25hp with the complete rear exhaust section changed out on these older Lexus's... Hope this helps and that is the best as I can explain the upgrade..

Lextech lighting is ok...You send in your cluster and it is about a 2 week turn around....Not too many other options available for the blackout needles...I have not had any problems with my Lextech cluster so far and it illuminates very well... That is the story with the cluster lighting... I also have the bleeding LCD screen on my climate control...I had the chance to buy a LCD replacement screen for $250 and I passed...Waiting for a better deal....I may be waiting a long time....That is not a cheap fix.... Ebay climate controls are used and they will go bad eventually too.... What options do know of for the bleeding LCD's?.... A suggestion - I bought an extra cluster off ebay and installed that and sent my original in to lextech, that way my car was not disabled at all...As soon as I got the cluster back I sold the extra one on Ebay and got my money back...I think I even made $20 if I remember correctly...

Get on EBay and buy either an 8 or 10 inch kicker subwoofer....That is a very good inexpensive subwoofer upgrade from stock...Any larger sub will not fit...I also have a Kicker KX kicker amp in the trunk too...Twice the sound as stock all for $250.00 off EBay... THis is a picture of my 300w 10" kicker sub without the top screen which I removed for the pic...Also my KX kicker amp in the trunk....

A few other suggestions that I would like to share to help make the car run more efficent - - Spark plugs and wire change- The bosche platinums spark plugs are probably the best after market spark plugs available for our lexo's for the price....Most of the high performance guys praise them over the stock old OEM plugs...Bosche wire sets are ok too...There are far better sparkplug wire sets available but they are usually twice the cost of the bosche wire sets....Wires and plugs help if you are do for the change and or tuneup..... - For a smoothe idle cleaning/spraying out the throttle body and opening and closing throttle body fly and spraying that too with STP carb cleaner has helped on several occasions when using aftermarket air filters or if it has never been done on your Lexo....Cleaning the fuel system via the seafoaming from what I just learned also helps if you are experiencing a bouncing or rough idle...Every time I sprayed out my throttle body the car idles much smoother...Something to consider... - Steel braided hoses....In my pictures you will notice I have no rubber hoses in or around my engine as I have fitted my original hoses with steel braided lining, even the smaller vacume hoses too......The steel braided hoses are slip ons that you can buy at most auto parts stores, Ebay, high performance shops etc......They are basically steel braided sleeves that slide onto and fit over the your original hoses.. I bought two steel braided hose kts for $50 each and that did the entire engine job...It is said you will never get a leak again as the steel braided hose covers preserve and protect the rubber hoses for the entire life of your car...Should never have to change out another hose again...Looks great and sheilds the heat and elements...A win, win, win in my opinon....DO NOT BUY SPECTER brand steel braided hoses as they are cheap and crap. Any other brand should work just fine if you decide to do this... - For interior decore lookd and upgrades look into Lextechlighting.com...This company can upgrade all your interior dash, climate control, and stereo lighting...I did my cluster to bright white as you can see in the pictures after my needles blackened out....$200 and way better looking then stock as shown in the picture above...... -

Right on Brian........ Regards from Santa Monica, Ca...

Dawg - Make sure you change your spark plugs after seafoaming...As the combustion chambers are extracting all that carbon buildup by seafoaning there is a good chance it could foul the spark plugs that are exposed to the carbon and foam.....A few SC owners that have tried seafoaming and had to change their spark plugs after the process....My biggest concern is if this seafoaming cleaning clogs the cats and or mufflers as all the years of carbon buildup is sent thru and out the exhaust system...I only have one main center magnaflow catylitic converter, and straight thru mufflers so I will probably be ok...but a stock SC exhaust system has 3 cats and two oval mufflers and I would be a little concerned about clogging.....I am waiting for some replies to these questions...I will post on this thread when I hear back from my Lexus buds.... Apparently the seafoam is mixed with water and you have to suck up the seafoam thru the brake booster line..You will also need to plug the other end of the booster wiht your finger so the car does not stall...Once the foam is in the engine they said turn it off and let the foam sit in the engine for 10 minutes or so....that is what everyone has done with their SC's.......Turn the car back on and major white smoke will come out the exhaust for a few minutes...I am finding out more and more about this seafoaming process.....I will get back to this thread shortly...I know about as much as you Dawg about this seafoaming but some guys said running it thru the oil and fuel makes a difference too, they said it really cleans the injectors and other things...I am just working on the engine seafoaming for now, tranny, oil, fuel I cannot comment on yet...Need more info, those ClubLexus links I will read over now....Thanks...

No problem bro!!! Hey I looked into Seafoaming and that is a fantastic thing to do on these older SC's...It has been reported to free up to 10hp on some of the older SC'S...I am doing my car tomarrow...Apparently there is massive carbon buildup on the internal combustion chambers that occures year to year.. so cleaning out the crud really helps especially if it has never been done before.... The process creates a lot of smoke when doing so, so I hope you have friendly neighbors....Once a year this should be done according to the experts..... Oil seafoaming is beneficial as well from what I have read, I need to look more into that aswell.... Also running one quart of transmission in with your oil for a few weeks is a good idea every two years or so....The one quart of transmission fluid acts as a detergent to clean internal parts...A complete oil change is needed after this process...I do that every other year or so..Helps clean, lifters, valves etc... Dawg - Your seafoaming suggestion has helped me out... I never took that process seriously until now....Thanks..

DAWG - you can pick my brain I don't mind...That is what the forums are for...INFO... BRAKES - The brakes you are about to purchase should be fine and you will definetely notice an improvement...Go for that...... Front and rear D/S rotors and high quility pads should be the objective.... I think OEM pads and Brembro rotors are the very best, but your listings to buy items should be just fine....I used China made no name D/S rotors and OEM pads..Bought them both off Ebay... I noticed a .30% increase approx. in braking power after the install.....After your new brakes are installed I also suggest doing a brake fluid change out or flush, that can help too if that has never been done on your car or if you have air in the lines...... INTAKE - The intake you should look into is the BFI intake for cost savings and efficency...... The BFI intake costs nothing and is an easy way to open up the airflow to the engine to help it breathe better...Better efficiency usually means better gas mileage too....The BFI intake is a custom modification of your stock filter box which is really proven to work better then all the expensive aftermarket intakes like mine.....Go to planetsoarer.com and look into the BFI intake....If you want to keep it simple just get a K&N filter to replace your stock filter and be done with it.....You will never see big power gains with these SC's when upgrading the intake or air filters...The stock intake is really not all that restrictrive... The BFI intake or a true cold air box intake are the best two intake designs for the Lexus's...Mine is a mix of everything and is probably equal to either but not better... Electrical - Replace the Negative big ground cable going from your battery to the engine block...It is about 3 feet long...The original ground cables can get crispy and deteriorate over the years and lose there potentcy.. Most people don't realise that you can lose power off those ground cables, and that is a proven fact.....That would be my first change out......Secondly for cost savings, I would get new Bosche spark plug wire sets and new Bosche spark plugs and install...I got mine off EBay for cheap...They are a good choice and not to costly...Thirdly, I would replace the two distributor caps and rotors as when recommended per the dealer scheduled maintenance.. I did all those things at once and noticed a difference... I also did a few other things too...That should cover your needs without breaking the bank... Seafoaming I have never tried and can't really comment on it.. I have not heard bad things about it... Exhaust- Ebay is where I got my Megan N1 straight thru mufflers. Really any straight thru mufflers will do, I picked Megan because they were on sale..They all pretty much perform the same... High flowing resonators are a must to reduce the exhaust noise....The final result of those changes will be slightly louder then stock...The Magnaflow 2 into 1 center cat is probably the best choice available when sticking with the stock exhaust piping..You cannot go wrong with Magnaflow cats.....The Blits Nur rear exhaust systems are a good expensive exhaust upgrade for around $700-$900...That is if you want to retain the stock exhaust look.... However, the Blitz will not out flow the straight thru mufflers and resonators that cost in total maybe $200.. The Cat and mufflers changes will bring a smile to your face...You will notice improved power and better better fuel efficency...The stock exhaust is so very restrictive... Exhaust mods are a must in my opinion on the older Lexus cars... Feel free to ask questions I don't mind answering...That is how I started out years ago....

0-60 is in the low 5's maybe, I can hang with the new 400hp Vette's so what do they do it in? Without the nos I beat out my best friends G35 infinity and can barely edge out the new stock 350Z... I have never ran the timed quarter mile, but plan to shortly.... I did dyno at 201rwhp which is like 260hp just yesterday without my computer management (Apexy piggy-back) hooked up and no NOS either....With the piggy back installed and tuned I should dyno closer 210RWHP or (275hp) which is the best I have ever seen on any stock internal 1992 SC400 in the United States...That was suprising to hear... I am posted on the lexus high performance forums, and that is what they are telling me.......In 1992 brand new these cars dyno's at around 175whp...Over the years the cars dip off considerable in power...Clogged exhaust, engine wear, electical all suffer and contribute to lost horse power... This is the dyno sheet I got yesterday...The 193whp was the first dyno with the A/C on by mistake the second dyno was better at 201whp with it off....Also a pic of my dead and disconnected Apexi piggy back ECU. I don't have a scanner so it is a little blurry...

My pleasure to be of help.... There is only one way to get the sc's moving from a dead stop and that is with an upgraded torque converter...That pretty much goes for any automatic Lexus SC,LS,GS, etc..They are all slugs at launch.. A cheap or let's say cheaper alternative for this upgrade is at Lextreme.com, where you send in your stock converter and they send it back recalibrated a week later...What I would do is first pick up a used stock torque converter for like $50 at a local junk yard and send that one in so you don't disable your car at some tranny shop for a week.....$400 I think is the cost for the recalibration and it should be no more then $300 for the complete install by any tranny shop... That will definetely get the car bolting 0-30mph...I know for me the Precision dragon torque converter for $900 got both my rear tires spinning from a dead stop and that was when my car was completely stock....It was hard to beat at that time 0-30moh.. The stock factory torque converter was designed for older folk by lexus, a huge flaw in my opinion...... Oh and driveabiltiy does not change, so you need not worry about neck jerks......You will still get those smoothe luxury take offs with the upgraded torque converter unless you hammer the throttle...There really is no other alternative solution to correct this horrible Lexus problem other then a supercharger or NOS system setup which is not a consideration for most......No premature transmission wear, or anything of that nature will ocure..Reliability will remain the same..I have had my upgraded torque converter for two years now and love it.. That takes care of that problem.. Brakes...Get on EBay and buy a front and rear set of Drilled and Slotted rotors for your SC400...Maybe cost around $150 or so...Then also try and buy the best quality brake pads and not some Pep boys cheap specials that will probably squeek anyway...Those changes will dramatically improve your crappy current braking system...$200 is a cheap price to pay for safety....I did that and literally got a %30-%40 increase in braking power...I have had these new rotors and OEM pads going for almost two years...No noise, good looks, even wear, no warping or cracking, etc..and I promise you will be pleased....Brembo rotors are the best, but I went with a no name brand of D/S rotors..and they have been vantastic and have givien me no problems to mention over two years...As you know with my car braking is a must.... That takes care of that problem... (no need to upgrade brake calipers or master cylinder) THis is what the new D/S rotors will look like minus the rims..they look nicer even on the stock lexus rims...Hope this helps...good luck...

I just wanted to ad this information for those SC400 owners that may decide they want to install headers...I installed the S&S Headers and experienced fitting problems...They have just came out with new true direct bolt on headers at EKTUNING.COM...They claim 20 hp gains but it is really closer to 25hp with the two small cat deletion....The price is $900... The S&S headers cost me $600 plus like $500 for custom fitment.... Headers are not much noiser then stock to my suprise...big noticeable power gains.... A upgraded torque converter and headers is a wicked and effective combination for more performance...Something to consider if you want to keep up with those Mustangs and Camaro's... These are pretty much the only headers that are available 1) The short headers in picture 1 is the S&S Headers (S&Sheaders.com) which I have in my SC400. (Major fitment issues) 2) The mid size direct bolt on headers in pic 2 are the EKtuning (Ektuning.com) headers.. (which I recommend, direct bolt on headers are easy and practical) 3) The long tubed headers in pic 3 are the TEX Headers (planetsoarer.com) that can only be purchased from Australia...(these probably flow the best) Hope this info helps someone....

No problem, Hope the info helps....