Turbo And Fuel Economy Discussion :P

[legend]

Nitrous Oxide

[The Last Streetfighter]

Let's first assume that you have fresh oil, fresh filters, good plugs, good leads, Good Dizzy, No dizzy oil leak, Fresh Gear oil, good fuel. Take care of the baby before you spend money spanking her!

I paid $400 for a full E-manage and looms and PC connectivity + $165 for dyno time to tune it up. (Home install of the emanage) and got good gains throughout the rev range. Min 2 kw (@4400) and Max 9kw (@ 6200). This includes ignition advance adjustment, fuel adjustment and air adjustment. And I have the peace of mind of knowing that my AFRs are now all where they should be.

A lightweight (4.5kg?) flywheel might cost you $450 to buy + $450 to install. Car will not be anymore powerful but will be noticibly faster through the gears. If you need a new clutch, use the opportunity to put the light flywheel in. Save on Labour cost.

Cheapest gain for buck would be a Decent CAI.

Biggest kw gain per $ will still be Turbo. Have a look at Talasas ride in the Member's Rides section.

[oldeskewltoy]

Many good thoughts and recommendations so far....

In recent months I've noticed that a 1.4 point jump in compression(very close to 11 to 1) seems to gain the most for "simple" power mods. I know two people who put down 118hp and 103 torque... at the wheels in AE86s(rwd) running stock cams with stock TVIS heads with compression at or close to 11 to 1. Stock compression AE86s usually put down about 103hp and 94 torque @ the wheels. 15hp and 10 # of torque are substantial gains when talking about 4AGE engine. Compression boost of only 1 point does improve power some, but getting closer to 11 to 1 seems to make a bigger difference than just going from 9.4 to 10.3.

Cams DO improve 4AGE power. Stock 4AG cams tend to fall off at 6600 rpm. Many of the drop in aftermarket cam models do help make additional power, especially after 6600. Power made below 6600 is usually improved some, but not by leaps or bounds(again this is for the "drop in model" of cam upgrade). Most drop in cams will add 1 or 2... maybe 3hp per rpm point too 6600.

[suss_slide]

hey micheal, ill give ya some money if you selling me them deep dish rims you were talking about...

[feral4mr2]

oldeskewltoy, are these guy's just running a thinner HG the acheive the higher c/r? i have the smallport pistons in the vermin, my 'butt' dyno feels this is much better than before with 9.4:1 jobbies i still need more for the short superkhana events i'e had it in. like i need shorter ratio 1st and 2nd gear!
though i think as bill said with the lighter flywheel is what i really need.? help it rev quicker.

[The Witzl]

upping compression is not something i would suggest for someone new to playing with cars.

If i were you, and Im being deadly serious, I would not bother with the engine, and concentrate on making your car handle better.
- swaybars
- springs
- shocks
- bushes
- camber bolts

Maybe buy a K&N replacement panel filter. The stock intake system is actually quite good (on the AE92 SX/GTi models especially).

If you still want more, then buy yourself a C56 gearbox (from a 20V 4age) and the matching driveshafts. They have a shorter 3rd and 4th gear which make driving more fun

You can add an exhaust, but it will sound like an amplified fart resonator. Seriously.

I have a 20Valve motor in my AE92 SX seca, and it has a stock exhaust. I am sooooo happy it does, because i dont get a headache from driving it.


The only good value $$/horsepower gain worth doing is a turbo or a full conversion to a supercharged 4A-GZE.

[MR22ZZ]

If i were you, and Im being deadly serious, I would not bother with the engine, and concentrate on making your car handle better.
- swaybars
- springs
- shocks
- bushes
- camber bolts

Quoted for truth... the handling of a car improves the driving experience so much. Trust me when I say you will always have more fun in the twisties then you do in a straight line with a 4A-GE.

[o_man_ra23]

Panel filters in many cases will outdo pod's due to the box design. And as mentioned, Toyota standard boxes on performance motors are generally quite good. Duct cold air into the box's intake (a funnel and polypipe is all you need) and you will get noticeable gains for no more than 20 squid.

Another good brand of panel filters (arguably better even) is Unifilter... just so you have options when you get to the shops.

I agree on the zorst... but would impose a 2" limit for NA and 2.25" for turbo when your dealing with a 1.6Ltr.

Fully agree with Witzl though, make the car corner and stop first, then worry about getting it faster.

[Michael]

Hey thanks for all the replies!

The deep dish rims arnt mine so sorry

One of the main reasons I want to improve the engine is because I would LOVE to be able to pull up next to a commodore or falcon etc and rip them to shreds at the lights. The other day I had a couple of guys in a holden ute shout out to me and told me to get a real car??

I figure turbo is a must if I want to be able to accomplish this, but on my budget its going to be a slow process so I think I might start of with the small things like new filter, cold air intake etc which I can afford (sort of haha)

The car seems to handle well, I dont intend on racing it too soon so Im not too worried about taking corners super fast etc atm.

Could you supply more info on how to duct cold air into the boxs intake? I think I know what you mean tho.

Also, I live in Adelaide where would a good place be to get the car tuned and dyno'd (or just dyno'd) I'd like to see how much difference I can make to the power over the year or something.

I intend on leaving the car looking stock (maybe different wheels if I want them wider and exhaust) just faster

Thanks, Michael

[oldeskewltoy]

oldeskewltoy, are these guy's just running a thinner HG the acheive the higher c/r? i have the smallport pistons in the vermin, my 'butt' dyno feels this is much better than before with 9.4:1 jobbies i still need more for the short superkhana events i'e had it in. like i need shorter ratio 1st and 2nd gear!
though i think as bill said with the lighter flywheel is what i really need.? help it rev quicker.

both are running thinner gaskets(without adjustable timing gears) one has high comp pistons fitted to low comp rods(rod was overbored to accept 20mm pin) The other had the block decked and the head shaved, the one with the high comp pistons also had his head shaved, but the block remained unchanged.

The down side to that much more compression... tough to tune(especially with stock ECU) requires the higest octane AND some ignition timing changes.

I run 10.3 to 1 now, in my car, I can run it on mid grade fuel(89 in the USA) with the stock ECU and stock timing. I'm currently putting down about 110-112** @ the wheels with a 94# torque reading. I'm using the very mild Web 294 grind camshafts (214 degree @ .050" lift. Total lift is 8.18mm) My dyno chart is posted in the "A" dyno pages.

** - part of my observations on the hp produced by drop in cams is based on my experience with Webs cam. the stock cam noticeably falls off after 6600 rpm. Every dyno I've seen on a stock 4AGE shows peak hp at 6600 with fall off after. The Webs don't fall off at/after 6600, they peak closer to 6900... BUT there is no noticeable drop off after that, even when I pull to 7300

Bill's suggestion... as always... is one of the best. #s at the dyno mean little except bragging. The flywheel upgrade is something you'll feel, as much... or more than the compression boost. There are many flywheels out there... and you can drop a fortune(OS Giken flywheel/clutch combo cost in excess of $1300). The easiest... safe... cheapest would be a simple upgrade to a blacktop (AE111) flywheel. The original 200mm clutch 4AGE flywheel has a mass of 7.2 kilos. the later fwd 4AGEs use a 212 clutch and a 7 kilo flywheel. The AE111 flywheel is a "svelt" 6 kilos. That is a substantial savings in mass... albeit you can get mass down to under 4 kilos with aftermarket flywheels. The reason I recommend the AE111 unit... mass savings and cost savings. I paid only $213 for my blacktop flywheel. Most of the name brand units out there(Jun, Toda, Tomei) will run in excess of $400.

[The Witzl]

Michael,

the response to the bogans in the commodore is simple..... "Hey, i dont need a massively oversized car to make up for whats in my pants"
Then, if you make your car handle, you can go around corners a lot faster than they can, because a commodore is a barge.

Save your pennies, and make the car corner and stop. Driving will be a lot more fun - especially with the adelaide hills in your backyard.

[o_man_ra23]

Witzl is right, no need to go faster to impress bogans... blowing them off wont show them up, it will just make them say other things. Build the car to how you want it, but it is most definitely important to make the car corner and stop better before engine improvements... as its for your own safety. Also if you really think your car handles well, go take an IS200 for a burn... you will realise then that it doesnt (I used to think my stock RA40 handled well... because it handled better than my brother's stock VH commo... how wrong was I??

If the bogans annoy you again, ask them to race... at a race track (racing on the streets is dangerous mmmmkay), and pick the tightest track with no straights. Your stock car will flog them.

[feral4mr2]

cheers oldeskewl, everything in mine is the stock 7 rib bigport bar the 10.5:1 c/r smallport jobbies. runs on the stock ecu etc. well. i do have a custim lightened 225mm 4agze flywheel, pressure housing with a performance 4age clutch plate. now i never weighed this over the stock 212mm flywheel i replaced as i didnt have any scales, but it did feel lighter for sure. i still dont get the zip i want in the first 2 gears. lower ratio diff perhaps......

or i'm expecting too much from a heavy car, havnt put it on a jenny craig diet yet.

[o_man_ra23]

Feral, if your racing, start removing excess carpets and interior trimming... anything that quietens the road noise is bad for performance... so all that must go (dry ice is great for removing sound deadening, there was a writeup on it somewhere)

[Andrew162]

Some damn good ideas in here, but Witzl's hit it on the head. My bog-stock-engined Celi can match it with the best of them round corners, and it doesn't even have to be lowered - just firmer with newer components. Swaybars make for good upgrades in handling as well as urethane bushes. My ride is damn fun to drive between here and the back roads to Lismore - some long straights and twisty corners that you could take at 100km/h if your car was handling properly (however the condition of the road there leaves a lot to be desired).

CAI (even a home-made jobbie) is a cheap upgrade, but this suits a pod filter better than a stock air inlet modification. K&N make replacement panel filters as well, so if you wanted to stick with N/A then at least you'd get a better air inlet flow. After the air is taken care of (if you kept it N/A) you can move onto plugs, dissy, leads, rotor, coil/igniter, etc.

Freeing up the exhaust is another way to make the car feel faster, ie. making it breathe better in order to match the intake and the ignition enhancements. "suck, squeeze, bang, blow"... if you've got the forst 3 sorted then the last one has to be factored in as well. You don't want a HUGE exhaust for N/A because they require back-pressure, and opening up the pipe diameter too far will make your car feel like it's getting nowhere through to somewhere in the mid rpm, then suddenly a burst of power as the exhaust flow and back-pressure is enough to catch up to the rest of the engine. Extractors are a simple mod, but make sure the primary and secondary pipes are a generous diameter (like about 1/4" - 1/2" bigger than stock, and the rest of the exhaust piping the same diameter (maybe 2") the whole way through.

This might sound silly, but it's a preventative maintenance measure - check all your connections are tight esp. vacuum, and replace frayed hoses. These often go unnoticed and unchecked, but they can cause havoc if you're chasing HP and working around these essential lines, and one gets unplugged or snaps off... your car hesitates or doesn't wanna idle properly, and you can't figure out why. The 'performance increase' you're chasing comes from all these other components too, working together... it's just basic stuff that shouldn't be overlooked.

But yeah, if you have the rest of that stuff sorted and wanna chase big numbers for dyno N/A bragging rights, THEN go with the engine mods. And yes, comparatively, turbos are less $$ to install than a decent (fiddly and time-consuming) N/A setup.