Cisco60

E.L. Prototypes in baldwin park makes a block guard for the xa/xb engines. their website is www.elprototypes.com and their blockguard goes for $175.00.

rebelMan

you're doing some nice work, i'm going to link this thread over to the forum so the echo guys can read up, i'm sure they'll enjoy the read.

keep it going dood m(__)m

sensez

sweet.

keep us updated.

sen-

aireck

all i can say wow... i can't wait to see what you get in the next couple of weeks....

KangaRod

Thats exactly right. I came from the Honda scene, and lots of guys would run the VAFC instead of the Uberdata and I'd always try to explain to them how its bad to try and trick the ecu - mainly because they (the ecu's) are so smart, and will often compensate for less load/hotter temps by adding timing, or vice versa
The safest way is to go with a standalone, but as you can imagine thats not always in the budget. LoL.

Nice write up, its really good to see some guys that are seriously into the performance aspect of Scion - its honestly depressing to come from a scene as hardcore as the Honda one and join a scene full of ricers (for the most part).
I dynoed my Vitz when it was basically stock to the tune of 93.6 whp. I have since added an AEM cold air intake and DC sports 4-1 header. I plan to hit the dyno again soon, the car certainly feels like it has another 10 horsepower.

I plan to add the TRD/Borla exhaust shortly - so I'm excited to see how much power that adds aswell.

uberscionofglendale

honda=hardcore? are we talking about the same honda and where did you get a vitz? i want a vitz.....but alas, we have to wait till next year. but, it is coming...woohoo.

BrianxB

Twiddler- being that you live in California, I would advise against milling the head to raise the factory compresion ratio. The best gas you can get is 91 from the pump and you have to travel miles to get anything better unless there is a Sunoco around you. Either way, your goals are quite optimistic but I think they are out of reach.

Xbilly

Oh, a naysayer... I think you should wait and see what kind of results he gets, the only reason to post negatively in this thread is to say "i told you so" some one has to try this stuff, or we'll never find out what works and what doesn't. don't discourage him.

sunoco is everywhere, and you dont know that he doesn't live only 10 minutes away from nevada or arizona. i dont know im just sayin

Twiddler

After the camcon unit produced 1hp, when I had hoped for 8hp, I would have to agree that 24hp is most likely out of reach at this point. I enjoy the science of testing and am still curious where things will end up. With a new AF unit, I think I can find 3-5hp. With clean ported heads, I think I can find 5-8hp. If this ends up being true, trying for 24hp and hitting 18 or more will still be a reasonable accomplishment. Getting more power out of the 1.5L is difficult at best. These engines are already tweaked hard. My friend "Bruce the Engineer" did a little math to show how advanced our little engines are.

Bruce the Engineer writes...
I did a quick scan of some specs looking at specific output, ie. hp/litre, to get an idea of how efficiently engines produce power. Here's a sample:

Scion Xb: 72.2 hp/l
Porsche Boxster: 88.9
Honda S2000: 111.3
These are impressive numbers. Now let's look at some less exotic engines:
Chev. Truck, std V8: 59.3
Monte Carlo V6: 53.9
Whitey's old 84 vette ( 5.7L, 230hp ): 40.4
2005 Mustang GT: 65

You can see why people modify these engines (big american V8s) and get impressive numbers. There is just so much potential that is not being used. And, like the stock market, people love talking in absolute gains in hp, rather than percent gains.

If we can find 20whp on an 88hp base, that's a 22.7% gain and pretty cool if you ask me.

Now with regards to 91 octane and detonation...what most people don't realize is...every engine will detonate at a given timing level. If you can control timing, there is a tradeoff that exists where you can often find more overall HP by increasing compression and backing off on timing. The power lost in timing is more than gained in compression.

As Westech Tom showed me at the dyno, the toyota timing is very conservative from the factory...remember these cars are built to go 300,000 miles. Even more proof that the timing is conservative is the fact that some supercharger companies offer bolt on at 6psi...this has to be sending compression levels up a few points.

There is an engine building competition called the "Jeg's Engine Masters Challenge" where one of the main rules is "the engine must run on pump gas". They use 92 octane and the engine that won in 2002 was 13.5:1. The engine that won in 2003 was 13:1, and the engine that won last year was 12.5:1. Yes these are purpose built race engines, but 11:1 in a street car is not that scary once you've seen 13. As long as you can test on the dyno and control timing, higher levels of compression can be used to find some power.

That being said, after discussing it with the lads at the dyno, I most likely won't shave my head for other reasons. I don't know the piston to valve clearance and I don't want to get that deep into a rebuild. It's more than I want to do. More importantly, I still don't know a good way to control timing.

On a side note, there are a couple other tricks to help reduce the chances of detonation when building a race engine on the edge:

1. polishing combustion chamber
the less rough surface, the less chance of a heat spot which could ignite the air fuel misture.

2. ceramic coat
ceramic coat the piston and the chamber and the valve heads to reduce surface temperatures to insure no hot spots. I just got a set of valves for my head and they look to be black ceramic coated right from toyota.

3. sand all piston edges
any rough hard lines on the piston top can be sanded smooth to again prevent hotspots from forming which could get unstable at the higher compression level.

4. drop the plug temp 1,2 or 3 levels
running with a cooler plug can often thwart detonation.

Again, every engine will detonate if you give it enough timing, the key is to find that optimal point of maximum timing at a safe area where you are maximizing power but not detonating.


hope these stories are amusing

Andy

Iheartdabox

just wondering what the engine life would be

hotbox05

what the engine life would be with what mods? probably close to the same. hey twiddler how much dide the head porting and valve job run ?

Newtmaker

This all brings back some fond memories! In 72 I bought a 72 Corolla with the 1600 "hemi" engine. A couple years later I was sent to Guam and took the car with me. Over there parts in the junkyards were cheap and plentiful. I got a used head, a 71 manifold (tri-Y design), and some larger carbs from other Toyotas. Ordered a cam from Crower and an intake from Edelbrock. Then I switched to dual side draft Webers! All in all I had agreat time and before it was over I had times in the 14's and a very upset wife!! She has since forgiven me ;-)
I look forward to more on this project as well. I just bought the factory manual and have been studying the engine sections. It is indeed a very impressive little engine. One spec says the engine is 187 lbs! Can that be right??
BTW, when I got rid of the car at 150K miles, the engine still did not burn oil and was strong. However, severa months later the oil pump did fail.

Walt

Twiddler

Iheartdabox, in terms of engine life, I think you are asking based on higher levels of compression? I tend to think the life would be similar to that of a superchargers. I don't see it being that much different than stock. In the old toyotas I've had, the engines tend to get loose after 200k+. You just end up adding more oil. Eventually you rebuild the engine which is basically new piston rings and bearings, maybe valve springs and maybe a valve job. If you mean engine life based on the current mods, like hotbox05 said, probably the same.

hotbox05, I haven't got a bill yet since the parts aren't back from EH. Here is their price list.
http://www.extrudehone.com/price_list2.pdf

The new valves were pricey...I think $300 for 16. I really didn't need to buy them but I am buying doubles of some things because I don't want a ton of down time when we start taking things apart. I just want to be able to swap heads out in a day and test the same day or next if possible. I'll lap the valves myself and take a few pics when I do since it's not too hard.

I also just bought the race injen, trying to snag maybe 2 more HP. ;) The length of the header/header extension combo often determines where peak power is made. The same is also true on the intake manifold/air intake side of things. Shorter pipes make for higher revving peaks and longer pipes make for lower revving. I don't know the science behind this but I believe it probably has to do with the air wave accoustics...maybe like a short flute makes higher notes and longer flute makes lower. If you look at our headers...they are relatively short. This makes good power at like 7-8 grand. LoL If there was more room before the cat, we could test different lengths. Some people do try spirals like on some of those muffler pics I saw in a different post. Really there is not much we can do on the exhaust side given room limitations.

But on the intake side, there are 2-3 intakes offered that are long. A lot of people think these make power because the air is colder. Cold air does make more power, but we are talking 2-3 degrees here and that is not gonna make a big difference...really the power in these units comes from their length...they are much closer to optimum length size for our given engine and 6500 redline.

I might get this on and be able to baseline with it before we head swap, or I might not. I'd like to...just depends on how much time and energy I have. I tend to think it will be worth 1-2 over the shorter injen.

Here is a optimum header length calculator for example
http://www.thedirtforum.com/headercalc.htm

since our engines are 1.5L (thank you to killerxromances for correcting me since I keep spouting 1.3 lol), I think that is about 92 cubic inches? Someone please correct me if I am wrong on this. Now say we want to turn 6000. Hmm I forget what our header pipe diameter is...maybe 1.25 or 1.5? Wow! Are headers are very close to optimal. I'm a little surprised. Seems to be in the 12-13" range.

Iheartdabox

i was thinking of supercharging my xb but im afraid that my reliablility of my engine will wear sooner.plus,i'm wondering if it will be worth the 3 g's

deviousXA

have you looked into the MEGA SQUIRT stand alone unit twiddler....i know on my last forums (mx6.com/probetalk.com) anyone porting/boosted/N2O would run this unit...im not sure how well it would preform on our engines but with the KL engine series they helped ALOT when it came to changing A/F ratio and adjusting the VRIS points on our engines just thought i would shed some light on another avenue if you didnt know about it already....i hope your able it hit your mark i would love to back up your progress with my own once all the preliminary trial/error are done

FrankenScion

Twiddler is my new hero.

jct

i think thats just the bare block alone

echocrazy

Good work! Having been around this engine and attempts to get more power from it for over 4 years I'm following this post with interest.

I have a couple of comments. Where did you get baseline of 88 WHP? I have seen properly dyno'd cars with this engine typically hit low to mid 90-95 WHP in stock form.

Your gain to 100 WHP is consistent with most header/exhaust, intake modifications I have seen on the car. Do you have the actual dyno charts? It would be intersting to see torque and HP curve differnces as you do these mods. Are you losing much low end torque? My concern has always been that you might get great peak hp numbers, but only have a small band of that power compared to the stock car.

27 hp with a 1.5 may be optimistic although increased compression might get you close if you can get timing and fuel management to cooperate and if you run race gas. Youre probably better off doing comparisons to other highly effecient small displacement engines in projecting anticpated power increases. Not a lot can be gained on this engine from what I have seen, but I would love to be proven wrong! Think I was looking at 12 whp for intake, throttle body. porting and header/exhaust. That would leave another 15 for compresion increase and better fuel management. I think thats a stretch on this engine especially if you start from more realistic low 90 hp for base rather than 88 hp.

Here are some other things to think about. If your increasing flow the throttle body can be a pinch point. Have you considered boring out the throttle body? I have also heard of some using injectors from the Corolla as the injector spray pattern is a littl more aggressive - may be urban legend, but sounds intersting.

When your talking about whp dont forget about some things that might help beyond the engine. Ligtened flywheel should equate to 1 or 2 hp at the wheels. Curious to know what kind of wheels/tires your running during dyno tests?

Twiddler

Hey echocrazy, you made some great points. Here are a few comments

<Base Figures>
I forget where I got that 88 figure. I thought I saw a couple charts on here but I might be mistaken. Let me check that magnaflow base test chart...hmm they went 97 to 102 in that article but perhaps started with an intake. I tend to think your 90-95 figure is accurate. I guessed that I was near 8hp because the magnaflow test picked up 5, and I felt that the injen and the headers probably picked up 3. So at 100, I figured I had picked up 8 which would put base in the 92 range.

I'm always concerned about peaks as well and also "curve teeter tottering". We were watching on the graphs for continuous gains. There is also a feature on SuperFlow dynos where you can average HP or TQ for any given dyno range. I usually average it for 2000-6000 and 4000-6300 or so to see if we really did make more under the curve power, as opposed to raising one end of the curve and lowering the other.

<optimistic>
Yes, I think 27 is optimistic at this time and 15-20 may be a better target. It most likely would take compression to get to 24+. My original goal was 8 8 8 and that was bolt ons, camcon, and then porting the head and intake and header. The electronic portion came up nil and so with a new AF computer on the way...that number may be 2-3 instead of 8. I am really not sure where the ported head will come in.

<throttle body>
I thought about this but they are over $700 at the dealer and I did not want to buy a second one at that price, nor screw up my existing one. I can only hope that it is not a huge choke point. I may look at it when the engine is apart.

<flywheel>
There might be some power here but I think light flywheels tend to help with acceleration, rather than total power..once the mass is spinning, it's not that much effort to keep it spinning or slowly acclerate it on a controlled dyno.

<wheels>
17" and was running 55lbs pressure. Pressure does matter on wheel dynos.

<power secrets>
In all truth, 95% of total power is the big three: heads, cam and compression. These are the heavy determanints to an engine's total power. Because this engine has variable timing, it makes changing compression and cams more difficult. With the engine apart, I might consider trying to make duplicate cams, with higher lifter acceleration rates (a more aggressive profile). This starts to lead into a chain of events though...then I need to run better springs. Can the little valves take more spring pressure? This is the world of unknown scion testing and starts to push the envalope and I'm not sure I want to be that radical on my daily driver. I'd like to play with compression, but we talked about it at the dyno and the piston to valve clearance with adjustable cam timing will be hard to calculate. I think we also wondered if the engine sensed more compression, would it try and compensate by taking out timing, thereby cancelling the gains?

<updates>
Just got the two giant factory scion manuals. These are cool $130 or so for both. I'll be away this week but I hope to have my parts back from extrude on the second week of july. Westech Tom is still waiting on the laptop adjustable AF unit. My guess is that we will be testing mid to late july.


Andy

Lip

Tom at

http://www.portflow.com/

Dave at

headgames...looking for site url

http://www.headgamesmotorworks.com/