jibbby

Xir- My boy, the fans are working like new and will not crap out I can promise you that, cooling is and always has been outstanding since the dual electric fan swap. I can't put the extra heat on anything other then the Headers and or the deleted cats..Sorry fellas and that is fact..Like I said the heat started right after the Header install....Open the driver door and you feel the extra heat, open the hood and feel the extra heat..It is what it is, I wish I could say different.....The spark plug comment was just a example, not so sure the 4 point plugs are all that bad though, and Xir where you did you get your info. on the plugs? I heard the 4 points are the best and release the biggest spark...I cannot comment on them from experience as I am and need to run cool temp plugs for my NOS system..Autolites nos plugs is what I am using now on my SC400.....

Jtucci - Ok, the 4.7 Liter Tundra motor has a high rise intake manifold that when measured and installed in an SC400 would hit the top of the hood..Big discussion on this swap on the Lextreme.com forums about a year ago...Yes the block size and bolt patterns are the same...Just keep us informed on how that swap goes for you...I think it's great that you are giving it a go....Best of luck....

CleanCL

never. ;]

you can buy an adapter for the 6 speed from australia.

MJHSC400

But -- staying on topic-- if you're building the motor up-- there's no reason not to go R154 and use standalone-- as you could spin the motor 8000 easily with a good balance--

And the cost difference for a standalone that can control an auto vs. a basic manual only version more than covers the difference--

THEN-- the SC470 would be a truly fast automobile. Probably wicked fast for a street car-- plus you could use a much lower diff. ratio-- like a 4.27 --

I would be more than satisfied with that setup -- and the dependability of N/A is well worth the cost of avoiding expensive turbo rebuilds and blown motor rebuilds from a dead injector or whatever......

MJHSC400

I've always heard that the +4's are a gimmick for power increase, but longevity is possibly increased-- Either way, the spark only goes to the shortest path-- so once one side of the electrode wears down, the spark will begin to jump to another one of the electrodes on one of the unworn sides--

The iridiums will wear longer than a single electrode plug, but may not wear longer than a +4, BUT will outperform all others during their service life duration--

The only possible advantage/drawback of the +4 is that the spark wave will be more shielded by the extra electrodes and obstruct the heat of the spark to some miniscule degree-- possibly lowering combustion efficiency compared to an iridium single electrode plug--

You guys remember the splitfire commercials-- that company is pretty much dead as all the hype was eventually debunked.. It became common knowledge that they were nothing more than a gimmick that made some guy/group of investors very very rich for some period of time...

Hey Jibbby, you said your temp. runs on 1/4 all the time??? Mine runs at 1/2 all of the time, whether sitting still or doing 85 mph... Regardless--

CleanCL

jibby - im not using the tundra manifold, it will look liked the stock lexus motor from the outside.

jibbby

Got it now....Thanks....

A true stand alone ECU can also help manage your automatic tranny codes and shifts better too...If you ever plan on boosting that 4.7 motor you better swap out the tranny...Holding power is compromised anywhere around 350-400whp on those automatic SC400 trannies over time......

CleanCL

yea i know, like i said, my goal is 300whp, i dont think ill go past 350 with the work being done, so this allows me to utilize the stock tranny/ecu, i'll go piggyback on the ecu for a basic afr, but with everything i plan on doing, 300whp shouldnt be a problem n/a and i think the tranny will be fine.

jgscott

iTrader: (1)

Not true. Guys this has been around a long time. It's Bore increase NOT stroke.
The conversion is close to a $ 10K + project to be done correctly and may yield 260 hp Max. Closer to 240 hp. Not real cost effective $$$$$. This ain't no Chevy Small block motor.

See post # 18, 20 and 25.
https://www.clublexus.com/forums/sho...t=44600&page=2

jibbby

I concure with jgscott....

In regards to your 300whp goals, that is fun and stong thru the first two gears but your upper gears there will be some let off...You will be very tough to beat 0-60mph if you have your traction setup just right...That's how it is with my SC400...That is if you decide to stick with the stock SC400 auto tranny and go with a different stall rate torque converter....

MJHSC400

so much for that


The tundra shortblock could still be used to do it though--

CleanCL

that guy bumped his up to a 4.9, i read a lot of posts, i read in earlier posts that utilizing the crank/rods would fit and achieve a higher displacement.

i think 10,000 is on the higher side.

BUT the sc400 heads will bolt up to the 4.7 shortblock. that i know for sure. i'm still trying to pull up borexstroke numbers from all the manufacturers.

either way in the end my SC will be a 4.7

edit:
sc400: 87.5 mm bore, 82.5 mm stroke
tundra: 94 mm bore, 84 mm stroke

so you are right, it is bore, but also the stroke. basically leaving 2 options. resleeving/honing the 1uz (pending the cylinder walls can handle the power, but if that other guy pulled off a 4.9 in his 1uz, my goal shouldnt be a major issue), or bolting up the tundra shortblock

jibbby

Just do a block bore on your stock 1uz-fe to your 4.7 and interchange the internal parts....

CleanCL

yea, that will keep the weight down, plus there are numerous practices i can utilize to keep temps and friction down.

jgscott

iTrader: (1)

Ever notice the the Stock air box is V funneled shaped to the back tube inlet ? If you put water in a funnel what does it do ? It takes the swirling splashing water in the wide top, and turns it into smooth even flow of streamed water out the bottom tubed in. Think about it.

Take a box 1 1/2 size bigger than the funnel. Cut a hole the size of the wide part of a funnel in the bottom. Seal the funnel water tight at the bottom. Fill the box with mildly pressured water and let it come out of the funnel. BFI concept.

If you dyno'd that intake you made and have against the BFI, the BFI will make more HP period. Its not the surface area but....... the engineering behind the size, shape, MAF size and resonator box in the sock system to flow air.

PS: "Torque Master" brand plugs are what you want. Dyno'd 5-10 hp gain on V8 Lexus motors proven.

jgscott

iTrader: (1)

He only got about 240 hp out of a 4.9 and he did port work and cam degreeing. Am I missing something you are thinking about doing ??

Taking the motor out, new water pump timming belt, headers. exhaust, gaskets, belts, more parts, mo parts $$, labor, 4.7 block. Putting the motor back in. You gonna have anyone measure and check deck height, clearances, ect ??? Maybe over $ 12K.

You ever pulled a motor out of the SC4. The top tranny bolts are a Bi_ ch. I did.

Better $$$ doing this. http://www.dynoperformance.com/artic...?article_id=10

With exhaust, intake port matching and flow bench head porting including the bowl, combustion chamber and valves. Maybe even lager intake valves. I might would also mill the heads 20 - 30,000's to bring up the compression a bit. Need to check that spec tho.