Why 3.0 sucks? - Page 2

Praufet · 06-03-2003, 11:31 PM

Output of toyota engines

According to this, turning the 3vz-e to a 3vz-fe would boost hp by 50 and ft/lb buy 20! This would give more hp than a stock 5vzfe, but less torque. I still looking into the possibilty of this.

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stanley · 06-04-2003, 01:18 AM

Hi everyone, I'm new here and just found this board. Actually I was referred here from another bulletin board. Anyway, I have a 1988 runner 5sp and I have been disappointed with my gas mileage too. What is the intake tube mod that I have heard about? I did a search for it and didn't really come up with much. Also, does a less restrictive exhaust do much to help with power or gas mileage? I am basically looking for the best bang-for-buck mods that I can do to increase my gas mileage.

Thanks,

Scott Stanley

rimpainter.com · 06-04-2003, 07:13 AM

Quote:

Originally posted by Praufet
Output of toyota engines

According to this, turning the 3vz-e to a 3vz-fe would boost hp by 50 and ft/lb buy 20! This would give more hp than a stock 5vzfe, but less torque. I still looking into the possibilty of this.

Have you guys ever driven a heavy vehicle with high HP and little torque? Yeah, it doesnt go anywhere at low RPM's. By all means, go for the swap, but when all is said and done, you are going to really need more torque.

My old 95 Civic SI with 4 people in it comes to mind. It was around 160HP with about 110ft-lbs of TQ...at 6K RPM! Yeah, city driving was really fun.

Let's be realistic here guys. We still have to match up the head design, oil passages, coolant passages, etc. Someone needs to get a headgasket from each engine and compare.

livelarg · 06-04-2003, 08:48 AM

Stanley:

First we need to know what engine you are running. The 4 cylinder, or V6.

as far as gas milage goes, It will never be great, but there are a few things you can do to get it better.
1) Tune up
2) Intake silencer removal mod. ISR mod
3) modify your driving style. In other words, The truck will only go so fast, mashing the throttle will just use more gas.
4) Free flowing exhaust.

on the front page of the website, there are a bunch of stuff if you scroll down, and a page dedicated to mods, check them out, they are great.
front page

Now back to the DOHC mod. This is something that we need to follow up on. I am going to talk to some toyota mechanics here, and see if I can get a head from a salvage yard cheap to compare.
If anyone has info, let us all know.

Robinhood150 · 06-04-2003, 09:31 AM

The 3.0L is a great engine...if you're living in Japan. I found this out when I went there last year. The Toyota engineers and managers are Japanese and grew up in Japan, they've never driven here in America. Their speed limit is 50mph, they have no hills like our rockies or sierras, and they don't tow anything. They have no concept of what we have to deal with here and are way too conservative to take risks by making bigger engines, they're going to stick with what they know and that's making small, relatively fuel efficient engines vehicles. Only now are they figuring out that americans want power and that's why the tundra is such a big hit. Nissan will likely find that out too with their fullsize truck.

beary58 · 06-04-2003, 11:20 AM

HI All

I’m new to this forum as my son (fooddude) owns a 94 4runner. I’m not a Toyota engine expert, but I do know a little in general about engines. In general, SOHC have better torque at the lower RPM range than the DOHC. I can see the DOHC work for everything except 4 wheelers who enjoy crawling through mud and over big rocks at lower RPMs. With that said, I enjoy mods like head swaps and making them work. So I’m not discouraging the idea, just giving some light to why the 4runner might be a SOHC.

Beary

Praufet · 06-04-2003, 01:08 PM

Seeing as I am not much of a 4 wheeler and my runner is just my transportation I am seriously lookign at this for a little more oomph and better mileage. Now if only I could get a job....

It's rough here in fort worth.

rimpainter.com · 06-04-2003, 01:08 PM

Quote:

Originally posted by beary58
HI All

I’m new to this forum as my son (fooddude) owns a 94 4runner. I’m not a Toyota engine expert, but I do know a little in general about engines. In general, SOHC have better torque at the lower RPM range than the DOHC. I can see the DOHC work for everything except 4 wheelers who enjoy crawling through mud and over big rocks at lower RPMs. With that said, I enjoy mods like head swaps and making them work. So I’m not discouraging the idea, just giving some light to why the 4runner might be a SOHC.

Beary

I agree with your theory - generally speaking. But explain to me why the D16Z6 (1.6 SOHC VTEC, 106lb-ft TQ ) has less torque than the B16A (1.6 DOHC VTEC, 111lb-ft TQ) then?

I dont think the SOHC/DOHC comparison is a rule of thumb.

oly884 · 06-04-2003, 02:59 PM

Ok, I've heard a lot about different engines, and bad gas mileage from the 3.0 L V-6. I know that those numbers don't mean much when looking at them in general, but I'm asking what, in the engineering, caused the Toyota 3.0 L V-6 to be crap. Along with the, dare I say, Ford 3.0 L V-6? Is it fuel injectors, a low compression ratio, or even just the valve lift? I still love my engine, I just want to know WHY it's the way it is.

fooddude · 06-04-2003, 03:56 PM

>>I agree with your theory - generally speaking. But explain to me why the D16Z6 (1.6 SOHC VTEC, 106lb-ft TQ ) has less torque than the B16A (1.6 DOHC VTEC, 111lb-ft TQ) then?<<

Hi 96

At what RPM are your numbers. Torque and horsepower change as a function of RPM. Other things are a factor also, but as a general rule, all things being equal, DOHC torque curve is lower at low RPMs but raise faster because of larger volume or air being pulled through from two sets of valves. That is also why dragsters prefer super chargers over turbos. Super chargers pump more air at low RPMs raising the hp and torque at the low end. Turbos generally kick in at the higher RPMs.

>>I dont think the SOHC/DOHC comparison is a rule of thumb.<<

NO it's not a hard firm rule, but it is a good rule of thumb. I don't knw why the 4runner 3.0 is a SOHC. I was just speculating that 4 wheelers in general need more power at lower RPMs.

Have great day

Beary

rimpainter.com · 06-04-2003, 04:04 PM

Quote:

Originally posted by fooddude
[BAt what RPM are your numbers. Torque and horsepower change as a function of RPM. Have great day

Beary [/b]

D16Z6 (SOHC) 106lb-ft TQ @ 5200RPM

B16A1 (DOHC) 111lb-ft TQ @ 7000RPM

KING · 06-04-2003, 05:32 PM

You guys make me hate my '94 TOYOTA PICK-UP 3.0 L V6 ever more than what I hate it now.

Bumpin' Yota · 06-04-2003, 09:21 PM

well I happen to LIKE my 3.slow...

gwhayduke · 06-04-2003, 09:27 PM

King...
I can't stand to see you unhappy. I'll give you $500 for yours and you can go get that new 3.4 in a Taco.

oly884 · 06-04-2003, 10:02 PM

Quote:

Originally posted by oly884
Ok, I've heard a lot about different engines, and bad gas mileage from the 3.0 L V-6. I know that those numbers don't mean much when looking at them in general, but I'm asking what, in the engineering, caused the Toyota 3.0 L V-6 to be crap. Along with the, dare I say, Ford 3.0 L V-6? Is it fuel injectors, a low compression ratio, or even just the valve lift? I still love my engine, I just want to know WHY it's the way it is.

I'm going to refer back to my previous post. I love my engine, it gets me where I want to go, and does good off road. I'm not bad mouthing this one bit, but I do want to know what causes it to be so bad. I know that it can't be just because it has a SOHC.

williemon · 06-04-2003, 10:10 PM

Bumpin Yota, Ive just been down your way to Ft. Meyers. Yall dont HAVE any hills.

I think the 3.0L is not powerful due to the head design and valve timing. You can get them to flow more air by modding the heads and exhaust and intake, so this helps HP, but I think to get the torque up there requires a different camshaft design. One of my cars (RIP) had a chevy 305 in it. About 140 to 150 HP at around 4500 RPM, but something like 220 to 240 lbs/ft of torque at 2400 RPM. Yes, it could make you feel pinned to the seat, but only up to 2400 rpm. Past that and it dogged out. It had a head and cam setup to max torque at the low rpms for a fuel effecient grocery getter. Now same engine, but designed for higher HP and a higher operating rpm was used in some Monte Carlos SS and some Camaros. Something like 190 HP but much less torque.
I say, give the 3.0L a better valvetrain and the performance can be there. Of course, a little more displacement wont hurt either.

oly884 · 06-04-2003, 10:15 PM

Ok, thats good to know. I knew that the heads arn't the best part of these engines.

gwhayduke · 06-04-2003, 10:16 PM

My personal opinion is that the problem is mainly due to intake and exhaust problems. The intake takes air in from behind the headlight (obstruction #1), air enters the airbox where the opening of the air meter is pretty small (obstruction #2), the air flow then passes through a maze (obstruction #4) on it's way to the plenum. On the exhaust side, the drivers right bank exhausts and crosses over to the left bank and enters upstream against the flow of the exhaust trying to exit the manifold. It then enters a pipe that is smaller than is optimum and then the Toy muffler is restrictive as well.

The restriction that most modifiers haven't either noticed or figured out what to do with is the restrictive opening of the air flow meter.

I'm still trying to figure that one out.

oly884 · 06-04-2003, 10:17 PM

BTW: Williemon, how much HP did you get from your head work?

oly884 · 06-04-2003, 10:19 PM

Quote:

Originally posted by gwhayduke

The restriction that most modifiers haven't either noticed or figured out what to do with is the restrictive opening of the air flow meter.

I'm still trying to figure that one out.

SAME HERE!!! I've looked through many different toyotas and havn't found any that will flow more air. I'd have to be a new unit, but of course that'd be cheap.

williemon · 06-05-2003, 06:02 AM

Oly, the head port and polish is rated by DOA to provide about 33 HP and the addition of the reground cams will provide maybe 8 HP more. So, around 40 HP more. The torque gains were not rated as being very much more than stock. Maybe 20 lb/ft more, but coming in a little sooner. This way, you feel the power come on at around 2200 or so, but you get a big kick when you hit 3000, and it seems to pull on up to 5000. I had to have a full 2.5" free flow exhaust to make the end results be as DOA designed. I have not modded the intake yet. Problem though is that I do like the added HP, I also wanted more torque boost down at 1500 and 2000 rpm which could not be had. I think this is due to that you have to modify the existing cam, and cant replace it with a cam that is really optimized for more low end torque. I may be wrong, but I like to think im right.

Praufet · 06-05-2003, 06:10 AM

Quote:

Originally posted by gwhayduke
The restriction that most modifiers haven't either noticed or figured out what to do with is the restrictive opening of the air flow meter.

I'm still trying to figure that one out.

Could you not do the ISR modw/ a cone filter and just stick a later model air flow meter on to the new intake pipe between the conefilter and the pipe. Personally it seems to me that the ISR + CONEFILTER = K&N FIPK.

livelarg · 06-05-2003, 06:14 AM

My 88' 3.0 has 250,000 miles on it, and it still runs perfect. And I have seen many other posts of guys with high milage 3.0's that are still running well.
I think that there is a trade-off with engines. Power or longevity. The more you soup up with power, the more sensitive the engine becomes. And I think Toyota wanted an engine that would last forever without much problems. This is especially important for people wanting to go in the backwoods. So do you want power or dependability?
Of course, Toyota prolly could have put a bit more power without hurting the engine. But we are also talking about and engine that was designed almost 20 years ago.
I also agree with the SOHC vs. DOHC discussion. Torque does come on earlier with the SOHC engine. But since I am on the road more than off-road, and it is my daily driver. I am interested in the DOHC mod if it can work out. I wonder if DOA has some opinion on it?

gwhayduke · 06-05-2003, 06:26 AM

The restrictive opening I'm talking about is the entry into the air-flow meter. Take the top off your air filter. Now tilt it back as far as it allows and look at the opening into the air flow meter. Unless I'm looking at it wrong, it looks like it's a much smaller cross section than the pipe leading from the AFM to the plenum. It seems to me that most of the mods are focused around getting more air into the air box. But none have looked at gettng more through the AFM.

Lucky · 06-05-2003, 06:33 AM

From my memories of engine tuning, 4 Valves per Cylinder doesn't always make a great deal of difference (and actually can make a negative difference) unless you are running high RPM. Larger Valves on a 2 valve design at lower rpm can actually be better and can often have a greater impact on Torque than more valves.

Probably more at stake here is the combustion chamber design or shape not creating the correct burn characteristics.

A decent tuner could probably mod the shape of the cimbustion chambers, port the valves, maybe rough up or smooth out the combustion chamber itself to create a different burn.

Quite often increasing the air available by supercharging, turbocharging or intercooling the engine can help but often the cimbustion chamber design is a limiting factor that makes the engine incapable of using that extra air drawn in.

With the DOHC heads you will probably find a considerable difference in combustion chamber shape, you may even find that the piston crow shape is different on the newer engine so just doing a straight swap may not be so easy as compression ration, burn characteristic etc maybe badly compromised.

I guess all engine design is a list of compromises and if you build an engine that lasts for 300K then I guess there will be a few compromises on the power, efficiency etc.

Remember some seriously powerful drag engines have been built out of motors that are basically truck engines, SOHC or even In block cam types but by concentrating on what the engine does with what it has to play with rather than worrying about the technology on board, they can come up with huge power outputs. Mind you they only last for seconds and you wouldn't want to drive one on the road.

Now the guy at Toyota who designed the 2LTE (2.4 Turbo Diesel) ought to have been taken out and shot - there are so many issues of head cracks after 50 - 60K miles that the guy must have been an idiot.

Cheers

06-04-2003, 08:48 AM	#29 (permalink)
livelarg Contributing Member Join Date: May 2003 Location: Oklahoma city Posts: 308	Stanley: First we need to know what engine you are running. The 4 cylinder, or V6. as far as gas milage goes, It will never be great, but there are a few things you can do to get it better. 1) Tune up 2) Intake silencer removal mod. ISR mod 3) modify your driving style. In other words, The truck will only go so fast, mashing the throttle will just use more gas. 4) Free flowing exhaust. on the front page of the website, there are a bunch of stuff if you scroll down, and a page dedicated to mods, check them out, they are great. front page Now back to the DOHC mod. This is something that we need to follow up on. I am going to talk to some toyota mechanics here, and see if I can get a head from a salvage yard cheap to compare. If anyone has info, let us all know. __________________ LIfe's short, Drive Hard! 88' 4Runner. ISR Mod, Airbox Mod. Kenwood CD with Hardwired Ipod 40 gig Infinity 6.5 seperates with Infinity Basslink Sub 91' Landcruiser 80 series 2" body lift 32-12.5 Swampers Hi-lift Jack Kenwood CD with Hardwired Ipod 40 gig

06-04-2003, 09:31 AM	#30 (permalink)
Robinhood150 Contributing Member Join Date: May 2002 Location: Wandering around Phoenix Posts: 6,043	The 3.0L is a great engine...if you're living in Japan. I found this out when I went there last year. The Toyota engineers and managers are Japanese and grew up in Japan, they've never driven here in America. Their speed limit is 50mph, they have no hills like our rockies or sierras, and they don't tow anything. They have no concept of what we have to deal with here and are way too conservative to take risks by making bigger engines, they're going to stick with what they know and that's making small, relatively fuel efficient engines vehicles. Only now are they figuring out that americans want power and that's why the tundra is such a big hit. Nissan will likely find that out too with their fullsize truck. __________________ Steve. '93 4Runner V6 Auto 4x4 Robinhood's Lair. \|\| Gettin' Off 4wd Club member Lots for sale:5.29 ARB IFS third member... Click Sierra Club policy: [A reason to close trails] ...Physical soil damage, often readily visible, resulting in: a. Erosion, causing soil loss and damage to stream banks, streams, and fish habitat... Lesson...Stay on the TRAIL!

06-04-2003, 01:08 PM	#32 (permalink)
Praufet Contributing Member Join Date: May 2003 Location: Fort Worth/College Station, TX Posts: 835	Seeing as I am not much of a 4 wheeler and my runner is just my transportation I am seriously lookign at this for a little more oomph and better mileage. Now if only I could get a job.... It's rough here in fort worth. __________________ --Brian '94 4Runner SR5 4WD 285 Terra Grapplers on FJ80 wheels\|Rancho 9000s on all 4 corners\|Cruiser coils\|Marlin Rear brake line Stereo CDT Audio CL-61A\|CDT Audio CL-6X\|Profile 640 and Profile 600M\|Audiobahn 100Q

06-04-2003, 03:56 PM	#35 (permalink)
fooddude Registered User Join Date: Jan 2003 Location: Edmond OKlahoma Posts: 737	>>I agree with your theory - generally speaking. But explain to me why the D16Z6 (1.6 SOHC VTEC, 106lb-ft TQ ) has less torque than the B16A (1.6 DOHC VTEC, 111lb-ft TQ) then?<< Hi 96 At what RPM are your numbers. Torque and horsepower change as a function of RPM. Other things are a factor also, but as a general rule, all things being equal, DOHC torque curve is lower at low RPMs but raise faster because of larger volume or air being pulled through from two sets of valves. That is also why dragsters prefer super chargers over turbos. Super chargers pump more air at low RPMs raising the hp and torque at the low end. Turbos generally kick in at the higher RPMs. >>I dont think the SOHC/DOHC comparison is a rule of thumb.<< NO it's not a hard firm rule, but it is a good rule of thumb. I don't knw why the 4runner 3.0 is a SOHC. I was just speculating that 4 wheelers in general need more power at lower RPMs. Have great day Beary __________________ 95 SR5 4x4 4runner Sony Xploid cd player(not sure which one) Rockford fosgate 900 watt 2 channel amp, 2 600 watt kenwood 10 inch subs. Some cheap cb from walmart Surco safari rack with 2 KC Daylighters 15x8 tech 1 rock crawlers Spintech exaust external fuse box mod. Airbox MOD. K@N Air Filter. ISR MOD Downey HD's

06-04-2003, 09:21 PM	#38 (permalink)
Bumpin' Yota Registered User Join Date: Feb 2003 Location: Sarasota, FL Posts: 3,639	well I happen to LIKE my 3.slow... __________________ 3vze, 4x4, sr5, 90, auto, LSD 2x dB Drag World Finalist 2003 Nopi Nat. Street B champ 2004 SBN Street C champ 2004 SBN Advncd NW Champ 2004 Former WR Holder in NW. SPL: 159.8db @ 42hz In loving memory of Jamie Riggs 5/15/85 - 10/8/04

06-04-2003, 01:18 AM	#27 (permalink)
stanley Registered User Join Date: Jun 2003 Location: Davis, CA Posts: 27	Hi everyone, I'm new here and just found this board. Actually I was referred here from another bulletin board. Anyway, I have a 1988 runner 5sp and I have been disappointed with my gas mileage too. What is the intake tube mod that I have heard about? I did a search for it and didn't really come up with much. Also, does a less restrictive exhaust do much to help with power or gas mileage? I am basically looking for the best bang-for-buck mods that I can do to increase my gas mileage. Thanks, Scott Stanley

06-04-2003, 11:20 AM	#31 (permalink)
beary58 Registered User Join Date: May 2003 Location: Oklahoma City Posts: 7	HI All I’m new to this forum as my son (fooddude) owns a 94 4runner. I’m not a Toyota engine expert, but I do know a little in general about engines. In general, SOHC have better torque at the lower RPM range than the DOHC. I can see the DOHC work for everything except 4 wheelers who enjoy crawling through mud and over big rocks at lower RPMs. With that said, I enjoy mods like head swaps and making them work. So I’m not discouraging the idea, just giving some light to why the 4runner might be a SOHC. Beary

06-04-2003, 02:59 PM	#34 (permalink)
oly884 Contributing Member Join Date: Dec 2002 Posts: 4,703	Ok, I've heard a lot about different engines, and bad gas mileage from the 3.0 L V-6. I know that those numbers don't mean much when looking at them in general, but I'm asking what, in the engineering, caused the Toyota 3.0 L V-6 to be crap. Along with the, dare I say, Ford 3.0 L V-6? Is it fuel injectors, a low compression ratio, or even just the valve lift? I still love my engine, I just want to know WHY it's the way it is.

06-04-2003, 05:32 PM	#37 (permalink)
KING Registered User Join Date: Apr 2003 Location: PEORIA, AZ Posts: 1,853	You guys make me hate my '94 TOYOTA PICK-UP 3.0 L V6 ever more than what I hate it now.

06-04-2003, 09:27 PM	#39 (permalink)
gwhayduke Contributing Member Join Date: Dec 2002 Location: El Paso, TX Posts: 1,576	King... I can't stand to see you unhappy. I'll give you $500 for yours and you can go get that new 3.4 in a Taco. __________________ '99 4Runner SR5 4WD, 5-SPEED. Abzug's vehicle for urban expeditions, navigating flash floods and debris flows (try 12-15 inches of rain in one week). It always gets her home. '95 4Runner LIMITED 4WD, 5-SPEED, over a quarter million on the original 3vze & headgaskets. TRD heavy duty clutch, TRD heavy duty flywheel, OME 900 springs and shocks. This old gal has gotten me out into the field, and back for 8 years, never failed to start or gotten stuck.

06-04-2003, 10:10 PM	#41 (permalink)
williemon Registered User Join Date: Jun 2002 Location: Georgia Posts: 811	Bumpin Yota, Ive just been down your way to Ft. Meyers. Yall dont HAVE any hills. I think the 3.0L is not powerful due to the head design and valve timing. You can get them to flow more air by modding the heads and exhaust and intake, so this helps HP, but I think to get the torque up there requires a different camshaft design. One of my cars (RIP) had a chevy 305 in it. About 140 to 150 HP at around 4500 RPM, but something like 220 to 240 lbs/ft of torque at 2400 RPM. Yes, it could make you feel pinned to the seat, but only up to 2400 rpm. Past that and it dogged out. It had a head and cam setup to max torque at the low rpms for a fuel effecient grocery getter. Now same engine, but designed for higher HP and a higher operating rpm was used in some Monte Carlos SS and some Camaros. Something like 190 HP but much less torque. I say, give the 3.0L a better valvetrain and the performance can be there. Of course, a little more displacement wont hurt either. __________________ 90 4 Runner 4x4 V6 Auto, Westin step bars, Eagle rims, DOA head port and camshaft. 94 Toy truck 4x4 22RE 5sp, 31x12.5 BFG muds, eagle rims, Rancho RS9000s, nerfs, ext. shackles. SOLD http://community.webshots.com/user/williemon

06-04-2003, 10:15 PM	#42 (permalink)
oly884 Contributing Member Join Date: Dec 2002 Posts: 4,703	Ok, thats good to know. I knew that the heads arn't the best part of these engines.

06-04-2003, 10:16 PM	#43 (permalink)
gwhayduke Contributing Member Join Date: Dec 2002 Location: El Paso, TX Posts: 1,576	My personal opinion is that the problem is mainly due to intake and exhaust problems. The intake takes air in from behind the headlight (obstruction #1), air enters the airbox where the opening of the air meter is pretty small (obstruction #2), the air flow then passes through a maze (obstruction #4) on it's way to the plenum. On the exhaust side, the drivers right bank exhausts and crosses over to the left bank and enters upstream against the flow of the exhaust trying to exit the manifold. It then enters a pipe that is smaller than is optimum and then the Toy muffler is restrictive as well. The restriction that most modifiers haven't either noticed or figured out what to do with is the restrictive opening of the air flow meter. I'm still trying to figure that one out. __________________ '99 4Runner SR5 4WD, 5-SPEED. Abzug's vehicle for urban expeditions, navigating flash floods and debris flows (try 12-15 inches of rain in one week). It always gets her home. '95 4Runner LIMITED 4WD, 5-SPEED, over a quarter million on the original 3vze & headgaskets. TRD heavy duty clutch, TRD heavy duty flywheel, OME 900 springs and shocks. This old gal has gotten me out into the field, and back for 8 years, never failed to start or gotten stuck.

06-04-2003, 10:17 PM	#44 (permalink)
oly884 Contributing Member Join Date: Dec 2002 Posts: 4,703	BTW: Williemon, how much HP did you get from your head work?

06-05-2003, 06:02 AM	#46 (permalink)
williemon Registered User Join Date: Jun 2002 Location: Georgia Posts: 811	Oly, the head port and polish is rated by DOA to provide about 33 HP and the addition of the reground cams will provide maybe 8 HP more. So, around 40 HP more. The torque gains were not rated as being very much more than stock. Maybe 20 lb/ft more, but coming in a little sooner. This way, you feel the power come on at around 2200 or so, but you get a big kick when you hit 3000, and it seems to pull on up to 5000. I had to have a full 2.5" free flow exhaust to make the end results be as DOA designed. I have not modded the intake yet. Problem though is that I do like the added HP, I also wanted more torque boost down at 1500 and 2000 rpm which could not be had. I think this is due to that you have to modify the existing cam, and cant replace it with a cam that is really optimized for more low end torque. I may be wrong, but I like to think im right. __________________ 90 4 Runner 4x4 V6 Auto, Westin step bars, Eagle rims, DOA head port and camshaft. 94 Toy truck 4x4 22RE 5sp, 31x12.5 BFG muds, eagle rims, Rancho RS9000s, nerfs, ext. shackles. SOLD http://community.webshots.com/user/williemon

06-05-2003, 06:14 AM	#48 (permalink)
livelarg Contributing Member Join Date: May 2003 Location: Oklahoma city Posts: 308	My 88' 3.0 has 250,000 miles on it, and it still runs perfect. And I have seen many other posts of guys with high milage 3.0's that are still running well. I think that there is a trade-off with engines. Power or longevity. The more you soup up with power, the more sensitive the engine becomes. And I think Toyota wanted an engine that would last forever without much problems. This is especially important for people wanting to go in the backwoods. So do you want power or dependability? Of course, Toyota prolly could have put a bit more power without hurting the engine. But we are also talking about and engine that was designed almost 20 years ago. I also agree with the SOHC vs. DOHC discussion. Torque does come on earlier with the SOHC engine. But since I am on the road more than off-road, and it is my daily driver. I am interested in the DOHC mod if it can work out. I wonder if DOA has some opinion on it? __________________ LIfe's short, Drive Hard! 88' 4Runner. ISR Mod, Airbox Mod. Kenwood CD with Hardwired Ipod 40 gig Infinity 6.5 seperates with Infinity Basslink Sub 91' Landcruiser 80 series 2" body lift 32-12.5 Swampers Hi-lift Jack Kenwood CD with Hardwired Ipod 40 gig

06-05-2003, 06:26 AM	#49 (permalink)
gwhayduke Contributing Member Join Date: Dec 2002 Location: El Paso, TX Posts: 1,576	The restrictive opening I'm talking about is the entry into the air-flow meter. Take the top off your air filter. Now tilt it back as far as it allows and look at the opening into the air flow meter. Unless I'm looking at it wrong, it looks like it's a much smaller cross section than the pipe leading from the AFM to the plenum. It seems to me that most of the mods are focused around getting more air into the air box. But none have looked at gettng more through the AFM. __________________ '99 4Runner SR5 4WD, 5-SPEED. Abzug's vehicle for urban expeditions, navigating flash floods and debris flows (try 12-15 inches of rain in one week). It always gets her home. '95 4Runner LIMITED 4WD, 5-SPEED, over a quarter million on the original 3vze & headgaskets. TRD heavy duty clutch, TRD heavy duty flywheel, OME 900 springs and shocks. This old gal has gotten me out into the field, and back for 8 years, never failed to start or gotten stuck.

06-05-2003, 06:33 AM	#50 (permalink)
Lucky Contributing Member Join Date: Mar 2003 Location: Hemel Hempstead, UK Posts: 88	Gas Mileage and Power From my memories of engine tuning, 4 Valves per Cylinder doesn't always make a great deal of difference (and actually can make a negative difference) unless you are running high RPM. Larger Valves on a 2 valve design at lower rpm can actually be better and can often have a greater impact on Torque than more valves. Probably more at stake here is the combustion chamber design or shape not creating the correct burn characteristics. A decent tuner could probably mod the shape of the cimbustion chambers, port the valves, maybe rough up or smooth out the combustion chamber itself to create a different burn. Quite often increasing the air available by supercharging, turbocharging or intercooling the engine can help but often the cimbustion chamber design is a limiting factor that makes the engine incapable of using that extra air drawn in. With the DOHC heads you will probably find a considerable difference in combustion chamber shape, you may even find that the piston crow shape is different on the newer engine so just doing a straight swap may not be so easy as compression ration, burn characteristic etc maybe badly compromised. I guess all engine design is a list of compromises and if you build an engine that lasts for 300K then I guess there will be a few compromises on the power, efficiency etc. Remember some seriously powerful drag engines have been built out of motors that are basically truck engines, SOHC or even In block cam types but by concentrating on what the engine does with what it has to play with rather than worrying about the technology on board, they can come up with huge power outputs. Mind you they only last for seconds and you wouldn't want to drive one on the road. Now the guy at Toyota who designed the 2LTE (2.4 Turbo Diesel) ought to have been taken out and shot - there are so many issues of head cracks after 50 - 60K miles that the guy must have been an idiot. Cheers __________________ Andy 1993 Toyota Hilux Surf (Japanese 4 Runner), 2.4 Turbo Diesel, Custom flush mount rear fog lamps, Ring front fogs and spots, Thule Roof Rack, Arrigoni and De Angelis roof rails, Sony Double DIN stereo, IPAQ GPS system.

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