1UZ vs. 3UZ Heads (Worked ie: Ported)

[Lextreme II]

As I asked of my second question about the stage 1 porting, I was asking what possible HP could be acheived ? And if anyone has actually done this and what was the result. I kinda of have a issue with this, as I know that a correctly ported head and valve work can improve the HP of a stock engine.
Just for refference I talked with Chris of AARP http://www.anderson-audio.com/projects.html. He owns many track records for Supra's and builds many 1000 + HP Toyotas. He thought that saying your could not acheive HP with porting and bowl work on the Non VVTI 1UZFEwas totally incorrect. He also mention that the NON VVTI V8 , N/A motors responded even better to porting and bowl work than others and would produce a true HP gain if done the right way.

My post was an inquire of anyone who has actually done this type of head work or know of, on the 1U- Non VVTI and there comments and actual results. I respect anyone's guess, but was seeking someone who may have actually done this on their car. Not someone who had a inexperienced opinion, and untested feedback. If edma65 has actually flow bench ported and worked the heads, and experienced results that dynoed 0 gain, then I guess I misunderstood or the heads were done incorrectly.

Sorry sincerely did not mean to confuse or flame.

BTW I have a 97 SC400 w/ BFI, X Dual, Unichip, 125 Shot Zex, and a few other Mods.

The answer will be NO.

* Different piston configuration
* Different head angle

However, if you can get a complete VVTi upper (heads and up) then it would work, but again you would have piston issue. To concluse your question, its not worth the money and time. If your desire is to have the 3uzfe, then you can do this:
1. complete heads and uppers (intakes and others)
2. Custom pistons to suite the 3uzfe heads
3. Other issues (VVti, fuel and ECU)

The cost might run up to 5k or so.....

 

[WDoherty]

jgscott- i remember a long while back someone did there own port work on their 1uz on this forum. You might search for porting or something similiar and come across this old thread. Then you could pm him and see what his results were, probably seat of the pants, or hopefully he would have the dyno. I know this is frustrating cause i would like to see some figures too, but this engine is in its infancy of modding in the u.s. and because of its small displacement people go straight to the forced induction due to cost per hp or max hp etc.

 

[ed_ma61]

stage 1 porting, isnt really 'porting' its simply to clean up casting dags and blend the valve seat machine marks etc. it will do close to sweet bugger-all for top end hp. it improves throttle response and low lift flow though.

no, ive never specifically ported a <97 1uz head in this minimal way though.

 

[ed_ma61]

1uz vvti pre and post port

1uz non vvti stock (also note, that the ported figures, whilst not listed, still dont even make it to the level of the vvti stock flow)

 

[Peewee]

So, the VVTi head has gone from 250 to 275.
That a 10% increase.
Is this considered huge?
Is it worth the $$?

 

[ed_ma61]

on an NA engine - yes. remember, every ounce of improvement builds together. thats the ony way to get the +110hp/L figures that define a truly beserk na engine. and yeah, 10% is very significant, with the important lack of low lift losses

forced induction? nup, i wouldnt bother with this level of porting and cost unless youwere wringing the last 2hp out of the thing

 

[turboandrew]

Thanks a lot for those numbers Ed. It looks like a stock 1998+ vvti head might be just fine for me with a .350 lift, ~235 cfm, which hopfully supports ~480 HP NA. That's what I'd like to see before adding a supercharger, around 400 rwhp, hopefully somewhere around 7500 RPM HP peak.

 

[jgscott]

OK hope Peter does not mind but.... this is very interesting. Porting is a art. Ed thanks for the info. Lets see another example listed here. OK whats the diffrence because it seems like your chart and person who ported shows less that 10% gain in flow.

Check out this other pre 97 1UZFE head porting example:

"The second very interesting bit is head porting. A 1UZ-FE head is flowbenched before and afterward being ported. Increases in flow on the bench usually relate directly to horsepower increases. After porting the intake flow increased by 19 percent and the exhaust by 14 percent!!! These are actual flow bench figures. Not only that but there are 12 full colour photos of before and after closeups of all the critical parts to pay attention to when porting. An extimated 20 hours was spent porting both heads.

http://www.clublexus.com/forums/showthread.php?t=31936[/QUOTE]I've seen this happen before, it depends on Who, does the porting and How they do it. 14 - 20 % is a diffrence.

 

[madboats]

Just some info on the flow of yhe 1UZFE heads. In standard form the heads flow 428 hp flowed at 28 inches of vacuum. With no more than 10 mins my mate who runs a head shop had the inlets at 548 hp. The problem we found was the exhausts were only flowing 62.5% of the inlets so to cure this we are looking to source bigger xhaust valves. Anyone know if there is an OEM valve that I could use to suit this application. ?

 

[rarson]

The characteristics of intake charge versus exhaust charge are monumentally different. There is a reason the valves are different sizes from the factory.

 

[Turbo4L]

quick question but would the 1uz (non vvti)heads fit the new 5.7?
and is the 5.7 block the same set up as the 1uz.
Which companies offer big cams for the non vvti 1uz.
Cheers

 

[toyotasrfun]

I don't know man, 500rwhp gets slow very fast. I know a few people with 650rwhp that can't believe how old it's gotten. One thing about the HP bug is that it keeps on biting, and demands more every time. I have a strong suspicion that when the Supra crowd gets a hold of this, they're not going to accept a cut in HP due to bad heads. We're pretty spoiled in the a lot of us run around town with 1000HP machines.

I've seen a few times where it's been theorized that the swap is complicated, but nothing ever shown. What is the basis of the difficulites, in your opinion? My 1uz is already at the machine shop with 2uz heads attached, all that would be needed a clean set of coil packs, an ECU, and a harness. All of which can be had for around $500.00. Is there somthing I'm missing?

Thanks man,

tell them to put it in a smaller car

 

[jibbby]

Is there any swapable bolt on heads out there that will perform better then the stock early model 1uz-fe heads on an N/A motor? Tundra heads on an early model 1uz-fe won't increase hp's over the stock 1uz-fe heads? I am reading this thread and it appears there is no need to upgrade the early model 1uz-fe heads if it is not AFI? Is this correct?

 

[mycarhasposessedme]

What is AFI

 

[jibbby]

Air Forced Induction....AFI (turbo, supercharger) or forced air induction. Is that right? Maybe I just made up that abbreviation...

 

[UZZ30-Québec]

Even if you'd swap VVTI heads, you couldn't use the VVTI so you'd always be stuck with the conservative cam timing. you might have a lot more low-end grunt, but forget about the 290HP.

also, the VVTI has 10.4:1, maybe a better exausth system, better injection system etc etc etc...

all this for a little 40HP ? just add headders/intake/exausth and maybe an aftermarket ECU and you'll have your 40HP. Also the intake is probably different because of the intake ports, probably the same thing about exausth ports. Now you've got a different intake, throttle cable, EGR, sensors and everything else is not the same...

Just thinking about this head swap and i'm getting sick trying to start the engine. You'd better buy a set of normal 1UZ and do a high quality port job on it. Yes, the heads can flow 550HP, but try to make that with a 4 liter engine, i don't think you wanna rev your car 9000RPM, especially with the auto trans.

it's just too much trouble to worth the swap IMHO.

 

[UZZ30-Québec]

oops, forgot to read past the 3rd page sry!

 

[jibbby]

Thanks for the reply, and that is what I pretty much thought.... Just making sure.....

 

[SuperRunner]

i'm not sure of the cam profiles, this is something i am curious about. Yet, i don't think there would be that drastic of a difference because they still needed the 2jz to idle like a lexus.
Also, most dynos that i have seen for auto sc300 is the low 170's and most sc400's in the high 170's, we are talking 5hp or so maybe. Those 1uz's i have seen with 200rwhp on manual conversions usually also have some sort of exhaust which accounts for a good deal of that increase, remember the 2jz is also working through that same bottleneck. I really want to hear from a head expert.

haha.. I have a GS300 with a NA-T conversion. With only 30 minutes of tuning on the dyno and 230,000 miles on the engine, I put down about 380RWHP on 11 pounds of boost before my boost controller fried. But that is a turbo, not the N/A.

 

[djr48312]

no need to flow more the 124cfm (per cylinder) unless you plan on making more then 600 flywheel HP. Typically it takes roughly about 1.5 to 1.6 cfm to to produce 1hp, so if each port could flow 124cfm, that that would give you 992 cfm total engine flow. with that said, 992/1.5 = 661 HP and 992/1.6 = 620HP again, these are rough flywheel numbers. obviously these are not exact as barometric pressure, temperature, humidity, ect. are going to effect this but it does give you pretty good idea.

As stated and or implied by Chris and Eric, to large of ports to get big flow numbers end up killing port airflow velocity and therefor causes major lowspeed and off boost (FI applications) drivability issues

124 CFM would support around 250HP naturally aspirated.