Lexus racing intake...

The 1UZFE EGR Delete Kit is available for sale here.
My research shows me that barrel throttles are better for airflow above 15k rpm and below that butterflies do better . Slides don't offer the smooth part throttle drivability that butterflies will.
 
Sorry but Reynard transverse box (Hewland gears) is fragile,will only handle about 350 lb/ft torque, if you try a start with hot tyres they will snap 1st gear input shaft! Contingency plan is Reynard Champ car gearbox.

Slide plates v Barrels v butterflys
Slide assy's are easier to manufacture, and if clearaces are adequate have no problems with thermal expansion or sticking.
Barrels- precision grinding and line boring, maintaining alignment with thermal expansion.
Butterfly's - again manufacture, alignment and expansion.
Sliding trumpets and top mount injectors - We don't have Williams or Cosworths budget. Current prices rebuilt (not new) NME Cosworth 3.5 ltr V8, 600bhp, Stg 52k. Rebuild at 10 hrs running approx Stg 20K
 
Hey MRS,

Well, that torque is quite suficient I think, for a street car (think light kitcar) but it's a pitty that the cases flex so much. then again if you have one.... Oh goodie. champcar boxes are expensive though.

I completly agree with your reaction to the slides/butterfly's/rollers thingy, manufacturing wise that's easiest,
I had those (dutch build though) on my sandrail Lancia engine worked great at high rpm only.
The other thing I had on it was Homebrew sliding trumpets, which are indeed quite easy to make, I had a twin input servo controller (very el cheapo but very efficient), looking at RPM and TPS at which values you could program a certain position, there where 24 positions in total and 12 by 12 input values. the trumpets where just Bellmouths welded to alloy tube. a inner vs outer diameter tube pair was made on a lathe , the innertube was flanged at the joint inside the intake tract, and the 1 mm widening didn't prove any loss on the dyno.
Dyno testing with the different settings was pretty timeconsuming, but satisfying, we gain a shedload of torque low down without loosing any on top thus having a very wide engine.

the manifold tube had a cut out and a ruber O-ring for sealing which proved more then adequate.

I believe the most expensive part was the Model airplane 12v Servo which could push 12 kilo's, it cost about 50$us, the controller itself was cheaper than the box it was build in.

the rest of the injection was VEN and ignition was some old stuff,

I would like to build the same system on a V8 jobby again when the time comes and the striker gets sold to fund the new project.

grtz Thomas

btw theres a F3000 box for sale at 6500 euro's.
http://www.racecarsdirect.com/viewlisting.php?view=2393
and a DFS engine for 11.000 pounds
http://www.race-cars.com/engsales/cosworth/1145620651/1145620651ss.htm
 
My research shows me that barrel throttles are better for airflow above 15k rpm and below that butterflies do better . Slides don't offer the smooth part throttle drivability that butterflies will.

How ?
Barrels and slides have an unobstructed passage at 100% open. How can one have better airflow at any rpm? Think about it!

Driveability ?
Have you driven a race car with all three variations? Part throttle drivability is about correct fuel and ignition mapping.
 
Well,

Yamaha uses butterflys on the 17.000rpm R6 engine without problems
and therby I think that in that sorts of high rpm tuning valve controll would be the bigger issue, not the type of throttle.

a rollerbarrel is best flowwise, but fuel atomisation can only occur far up in the intake trackt when it's used in the rpm range it's build for. that seems to be because of the absence of vibration/swirl (whatsit called in english again?) in the airstream which is normaly provided by the throttle valve. it's not used in some very high power aplications WHY??? well the atomisation thing sounds like the reason.

there's no such thing as a drivable pure NA race engine.

just the best of both worlds which seem to be both build by toyota 4age NA 20v and the UZ series with a lot of work.

grtz thomas
 
rms,
two questions: why did you use the 1uz instead of the 3uz? and do you think a flat plane crank will add some rpms and able to balance. that's my goal: flat plane crank in a 3uz, na. any advice?
thanks,
wes
 
Sorry I should have quantified myself. For applications where fuel is injected below the throttle plates, slides, and barrels should offer very little difference in performance. Although flat slides will tend to vector the airflow at part throttle applications. When the flat slides are partially open there is a large lip for airflow to make an abrupt change around. There is a large amount of turbulence created by flat slides at part throttle. Barrels will smooth the part throttle airflow better than flat slides but not as well as butterflies.

Barrels and flat slides will both work as well at WOT, better than butterflies. In applications where fuel is injected above the throttle plates flat slides tend to have "issues" with smooth part throttle drivability. Although the flat slide can help atomization to a degree the radical transistion air has to make is hard to overcome.

You are exactly right, with the advent of modern fuel and ignition control drivability is a tuning issue. When you inject fuel below the throttle plates some of the issues with the flat slides and barrels are alleviated. But with mechanical injection like the Porsche MFI with flat slides, you will have to deal with drivability compromises at part throttle.

For most applications butterflies will work better than the other options.
 
Agreed.
We are injecting fuel below the slide to minimise part throttle problems.
On a practicel level however, the Hart 416B,420R,Cosworth BDD and DFV injected fuel above the slides and with changes to the metering cam shape (Lucas machanical) could give very smooth and linear throttle response in the rpm range they were meant to operate in.
 
Unless the car meets F5000 regs there is a 4 ltr limit.
Gee I wish you were one of my customers !
Manufacture a single plane crank, 4 camshafts, sell you a Motec ECU to handle the revised firing order, ongoing development to sort out the vibration problems,a holiday in the Bahamas, Monaco Grand Prix, YES PLEASE!!!!!

Try a 180 deg cross over exhaust. Sounds the same and even if Burns Stainless made it for you in Titanium it would be a lot cheaper than what I have in mind.
 
Those engines were designed to idle at 5-7K most of these guys will never have a street car that turns 7K. But I bet if the time was spent grinding the cam it could get pretty good.

Have you ever dynoed one of these engines with crossover headers? On a small block Chevy packaging constraints will make a set of cross over headers far from optimal for a high rpm engine. Runner length is too long. I would love to run a set of 180 deg headers on my race car. They would definitley sound sweet as hell.
 
Hi Rms,

I would be interested to know more about your front engine plate. I have been thinking of building one with an original spec oil pump machined into it and also possibly a water pump too. I am planning on building a 6:71 roots blown Drag engine of around 600 - 700 hp running efi and custom intake enclosing side feed injectors. The engine plate would mount the engine to the chassis and also allow for a crank pully support.

I am no mechanic so it's mostly in my head at the moment although the parts are getting gathered.

Oh just remembered you are using a dry sump. What a bout water pump?

Nath
 
rms,
of course, i like the sound but i am putting this engine into a gt40. so i am limited to the exhaust i can have: "bundle of snakes".
wanted the flat plane crank for higher rpms. lot of problems, eh?
is vibration a real problem?
another question then: how much oversize can i sleeve a 4.3? any? also, i need a source for itb. any sellers in so cal?
thanks for your help.
wes
 
Nath,
Could be done, approx $2.5/3k for plate with oil pump. Use original front cover, water pump and plate/s bolted on for mount and support.
 
rms,
ok, i give - no flat plane crank. darn.
the engine in Garvie's DRB gt40 is a 4.6 mod ford engine. very large heads. i purchased a rcr gt40, alum monocoque chassis. tried the 4.6, way to big. switched to the 4.0 lexus. still pretty tall. will have to modify the rear deck lid. check out this website:www.gt40s.com/forum/gt40-australia/19483-lances-build-part-5-a.html
i need itb that do not stick up very high. any ideas? what about increasing the bore on a 4.3L? any room to sleeve it?
wes
 
I was looking at my engine this weekend and decided that a drysump system should be very easy to reduce the overall hieght of the engine. I think I could do a custom drysump pan out of billet with four suction ports. THis would give me a pan height of about 2 inches max, plus my design would have maximum rigidity for the bottom of the block.
 
rms,
ok, i give - no flat plane crank. darn.
the engine in Garvie's DRB gt40 is a 4.6 mod ford engine. very large heads. i purchased a rcr gt40, alum monocoque chassis. tried the 4.6, way to big. switched to the 4.0 lexus. still pretty tall. will have to modify the rear deck lid. check out this website:www.gt40s.com/forum/gt40-australia/19483-lances-build-part-5-a.html
i need itb that do not stick up very high. any ideas? what about increasing the bore on a 4.3L? any room to sleeve it?
wes

Wes, these guys: http://www.a1turbos.co.nz/ build a very compact ITB setup for the 1UZ motor, but they're not vertical, and I'm sure you're looking for vertical ITB's for a GT40.

You think you have height & space problems? Look what I'm trying to stuff into my GT40 project:
 
GT40PNHD - Don't try to bore or stroke the UZ, just no sensible gains to be had. A mate has done the modelling and it's a very very poor mod on the bang for buck scale, not to mention if you get it wrong you'll go backwards.

Why not turbo or SC if you are looking for grunt? Just the stock motor produces fantastic results with either. SC will be in keeping with the genre of car but seeing you have already gone multivalve and twincam why not go the whole hog and go twin turbo? 400rwkw is dead easy
 
Have any of you guys tried working with any larger liter V8 engines? The Xuz-fe family of engines are really small V8 engines compared to let's say the alluminum block GM motors, etc... Are you guys building these engines up because you are in comp builds, or is it that you don't have good access to let's say the LS1 engines in Australia, that with performance cams and exhaust mods deal out 400whp easily - N/A....

An example: Ls1 motor is actually smaller and lighter in weight then any Xuz-fe motors....Just curious? Or is it a just a preference (dual over head cams maybe?)
 


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