Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

yabaiani
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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby yabaiani » Sun Feb 16, 2020 3:21 pm

oldeskewltoy wrote:Sorry this is my first appearance... I typically avoid ITB threads... they aren't often needed(my 140+ whp smallport runs just fine on a single T/B), and if not done correctly can and often does cause operational issues do to poor set-up (mechanical, as well as from a management POV)

yabaiani wrote:
I am absolutely doing the headwork right now too, no worries. :)


would love to see your work.......


yabaiani wrote:
Let me go ahead and update everyone on the parts and build on what I decided to do. I am:

* Rebuilding motor with higher compression, new forged pistons, rods, valve springs, retainers, etc
* new Tomei Poncams
* Toda cam gears
* Toda timing belt
* MRP ITB Kit w/ new injectors, fuel pressure regulator, vacuum block, etc (https://www.mrpltd.co.nz/product/mrp-4a ... le-bodies/)
* Fujitsubo super EX headers
* Fujitsubo legalis-R exhaust
* standalone ECU and new wiring harness


What springs? Why retainers if you are running such mild cams?


yabaiani wrote:random note...does anyone know of a good set of pistons and rods (not from MRP)? My machine shop said they would look, and I look at CP and only found pistons, not rods. Went to Brian Crower and found Rods. Don’t know if anyone makes both.

Arias just makes pistons...



Molnar Rods... they run about $450 per set... They have 2 different rods depending on which crank you have....

As to pistons, plenty of places make them... not many that you can trust - if you are going to spend $$ on forged pistons - get the right ones! But for your build level(cam choice) you don't need fancy pistons......


I probably put more things for generic engine rebuild stuff on things that I decided to not go with. Do you have any recommendations? Here is my compiled list so far...


Pistons:


Valve Springs


Cams:

Connecting Rods:


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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby Nick94tt » Sun Feb 16, 2020 6:37 pm

Fuel type, goals, driving style.

Running Pump 93, E85, or race gas?

Hp/tq goals?

Daily driver, road race, drift, drag, mix, etc?

Really basic oversimplified questions but they set the table.

Not trying to nag or be a pita at all. Narrowing these things down first just makes victory more likely. ^_^

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby yabaiani » Sun Feb 16, 2020 6:47 pm

Pump 93, daily driving (really once a week on weekends to cruise around), HP goal, maybe around 140-170 ish.

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby yabaiani » Sun Feb 16, 2020 6:47 pm

Nick94tt wrote:Fuel type, goals, driving style.

Running Pump 93, E85, or race gas?

Hp/tq goals?

Daily driver, road race, drift, drag, mix, etc?

Really basic oversimplified questions but they set the table.

Not trying to nag or be a pita at all. Narrowing these things down first just makes victory more likely. ^_^


Pump 93, daily driving (really once a week on weekends to cruise around), HP goal, maybe around 140-170 ish.

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby Nick94tt » Sun Feb 16, 2020 6:58 pm

Occasional track day/drift/autocross?

Jondee was 1000% right btw. Street cars are fun. Race cars are way too serious. :D

I can vouch for this. I've got a big single turbo alcohol injected car. The couple times a year I actually let the thing eat, it's epic. The rest is really loud cruising waiting to get pulled over. :lol:

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby yabaiani » Sun Feb 16, 2020 7:08 pm

Nick94tt wrote:Occasional track day/drift/autocross?

Jondee was 1000% right btw. Street cars are fun. Race cars are way too serious. :D

I can vouch for this. I've got a big single turbo alcohol injected car. The couple times a year I actually let the thing eat, it's epic. The rest is really loud cruising waiting to get pulled over. :lol:



More like a high quality build for street. If I want to go on the occasional track day, I don’t want to worry about the motor

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby Nick94tt » Sun Feb 16, 2020 7:14 pm

yabaiani wrote:More like a high quality build for street. If I want to go on the occasional track day, I don’t want to worry about the motor


That, the resident engine gurus can work with. ^_^

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby yabaiani » Sun Feb 16, 2020 7:15 pm

Nick94tt wrote:
yabaiani wrote:More like a high quality build for street. If I want to go on the occasional track day, I don’t want to worry about the motor


That, the resident engine gurus can work with. ^_^


I definitely want to be able to push it up on the redline but not feel like the motor can’t handle it. Or that something will break in it. My motor is already completely disassembled so I want to do it right once.

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby Nick94tt » Sun Feb 16, 2020 9:32 pm

Good bearings, balanced internals, and an uprated valvetrain will raise the "safe" rev limiter.

Build for 9k, rev to 8k... No point revving that high if the powerband already dropped off though.

Nothing you're after here is crazy.

That said, I keep hearing "K swap" in my head. :lol: ~200hp/~165tq for a stock Acura tsx motor.

Sound wise - no contest.
Drive wise - Massive torque (by comparison) wins.

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby oldeskewltoy » Mon Feb 17, 2020 8:14 am

yabaiani wrote:
I probably put more things for generic engine rebuild stuff on things that I decided to not go with. Do you have any recommendations? Here is my compiled list so far...


Pistons:


Valve Springs


Cams:

Connecting Rods:



NOTE: The Molnar rod you chose is special, please verify that is the one you need.... It is special because it is the only aftermarket rod that fits the "small" 40mm rod journal crank, and yet still allows a 20mm wrist pin (more common piston options)


JMHO....


Rods: You don't need the BC rods with the upgraded bolts, the ARP2000 bolts are just fine. The rest of the rods are all pretty much interchange-able. For point of reference... my smallport uses a "small" crank (40mm rod journal) and the "small" crank's rod (40mm big end, 18mm small end). So, if you have a nice set of OEM rods... you don't need new ones - although I would recommend new rod bolts. The biggest advantage to new rods, is saving on mass. One exception if you indeed have the small crank, the Molnar rod you listed is the best option.

Valve springs: Of those you listed I prefer the Toda, they work for many cams. The HKS springs would work in your build too, I just prefer the Toda.

Pistons: BRRRRRRR...(nearly all aftermarket piston listings are built off inaccurate information!!) For your build... of all your choices.... I'd either go with the smallport piston... OR CP 373102, or the custom piston from JE, or any other piston maker really... as long as it is custom. The CP373102 has the right dome volume for your particular build - as long as your head porter doesn't add too much volume to the chambers.


Cams: .... The Poncams should get you where you want to be 140-160hp, although if your head is properly ported there is no need to limit lift to under 8mm. There are other cam makers, Web Camshaft in the USA, and Cat cams in Belgium both make a "264" type cam with lifts over 8mm. I would recommend adjustable timing pulleys and using them to set cam timing.

Nick94tt wrote:Fuel type, goals, driving style.

Running Pump 93, E85, or race gas?

Hp/tq goals?

Daily driver, road race, drift, drag, mix, etc?

Really basic oversimplified questions but they set the table.

Not trying to nag or be a pita at all. Narrowing these things down first just makes victory more likely. ^_^

yabaiani wrote:Pump 93, daily driving (really once a week on weekends to cruise around), HP goal, maybe around 140-170 ish. More like a high quality build for street.



The formula isn't all that hard.... 1) 10.5:1 to 11:1 (calculated on YOUR build), 2) get the squish gap down to between .8mm(.032") to .9mm(.036"). 3) Don't overcam the engine - most "272" type cams are excessive for a mostly street build, they make peak power at, or above 8500 rpm, where as most 264 type cams pull to about 500 rpm less, yet usually offer more mid ranger power.

yabaiani wrote:If I want to go on the occasional track day, I don’t want to worry about the motor


OIL..... if you want a 4AG to survive.. it needs a large oil supply, along with an appropriate cooler. The only one making a nice big oil pan is MRP. As to coolers, go with something that is thermostatically controlled. If using a largeport head - the addition of an intake side oil drain will help. Finally, Toda makes steel oil pump internals - more stout then the original internals.
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby oldeskewltoy » Mon Feb 17, 2020 8:20 am

one quick note... When talking about cams you will see me put a number in quotes, followed by "type", as in "264" type. Not all cams are equal. because of this I tend to look at a cams duration numbers based on what duration they are at either .040"(1mm), or .050" lift. This measurement tends to be a bit more telling of the cams operational range
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby yabaiani » Mon Feb 17, 2020 10:53 am

oldeskewltoy wrote:one quick note... When talking about cams you will see me put a number in quotes, followed by "type", as in "264" type. Not all cams are equal. because of this I tend to look at a cams duration numbers based on what duration they are at either .040"(1mm), or .050" lift. This measurement tends to be a bit more telling of the cams operational range


Got it on everything. And one clarification, when you mentioned the piston recommendation, either smallport, JE custom (or any custom), or the CP 373102, do you mean Arias 12.0:1 Pistons (3731320) - $569 USD?

https://cp-carrillo-catalog.cld.bz/CP-C ... /10#zoom=z


Or did you mean this one:

Image



Also, updated my list with some new parts that I would love some thoughts on by your oldskeyltoy or jondee86.

Pistons:



Valve Guides:

Valve Stem Seals:

Valves:

Last edited by yabaiani on Mon Feb 17, 2020 5:41 pm, edited 1 time in total.

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby jondee86 » Mon Feb 17, 2020 1:19 pm

This discussion is out of my league now. My ITB engine was an unopened factory
stock AE92 smallport with about 60,000 miles on it that I bought from a wrecking yard
I ran the factory AE86 cast iron exhaust manifold and a 2" exhaust; dropped in some
second hand 272/268 cams with around 8.5mm lift; built my own intake setup with
used AE101 throttles and added a basic aftermarket ECU.

I figured that would work good enough for what I needed as Toyota built the 4AGE to
take a beating :) I probably put more than a thousand hours into putting all the pieces
together and tuning it myself. That was the real challenge and the most rewarding part.
It would have made more power with a bunch of engine work and new parts, but my
goal was to prove that you could have fun with a bog standard engine and a few bolt-ons.

https://www.youtube.com/watch?v=4MSwjxtLPLE

Engine redlined at 8000rpm, made peak torque at 6000rpm and max power at a little
over 7000rpm. It started, idled and drove almost like stock and would pull 4th gear on
uphill grades down to 2000rpm if I used the throttle gently. So if there is a lesson to be
learned it is to make sure all the components you purchase will work in harmony with
each other. Decide where you want your engine to run best and choose camshafts,
compression ratio, exhaust and intake systems that focus on that part of the engine
speed range. Don't go for more than you need... therein lies frustration and tears !!!!

Cheers... jondee86
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persists in trying to adapt the world to himself. Therefore, all progress
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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby yabaiani » Mon Feb 17, 2020 1:50 pm

jondee86 wrote:This discussion is out of my league now. My ITB engine was an unopened factory
stock AE92 smallport with about 60,000 miles on it that I bought from a wrecking yard
I ran the factory AE86 cast iron exhaust manifold and a 2" exhaust; dropped in some
second hand 272/268 cams with around 8.5mm lift; built my own intake setup with
used AE101 throttles and added a basic aftermarket ECU.

I figured that would work good enough for what I needed as Toyota built the 4AGE to
take a beating :) I probably put more than a thousand hours into putting all the pieces
together and tuning it myself. That was the real challenge and the most rewarding part.
It would have made more power with a bunch of engine work and new parts, but my
goal was to prove that you could have fun with a bog standard engine and a few bolt-ons.

https://www.youtube.com/watch?v=4MSwjxtLPLE

Engine redlined at 8000rpm, made peak torque at 6000rpm and max power at a little
over 7000rpm. It started, idled and drove almost like stock and would pull 4th gear on
uphill grades down to 2000rpm if I used the throttle gently. So if there is a lesson to be
learned it is to make sure all the components you purchase will work in harmony with
each other. Decide where you want your engine to run best and choose camshafts,
compression ratio, exhaust and intake systems that focus on that part of the engine
speed range. Don't go for more than you need... therein lies frustration and tears !!!!

Cheers... jondee86


well said sir. I'll shoot oldskewltoy a note and see if he can take a look at the thread and chime in. I love everyone's perspective. I dont want to mess this up!

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby oldeskewltoy » Mon Feb 17, 2020 5:42 pm

yabaiani wrote:
oldeskewltoy wrote:one quick note... When talking about cams you will see me put a number in quotes, followed by "type", as in "264" type. Not all cams are equal. because of this I tend to look at a cams duration numbers based on what duration they are at either .040"(1mm), or .050" lift. This measurement tends to be a bit more telling of the cams operational range


Got it on everything. And one clarification, when you mentioned the piston recommendation, either smallport, JE custom (or any custom), or the CP 373102, do you mean Arias 12.0:1 Pistons (3731320) - $569 USD?

https://cp-carrillo-catalog.cld.bz/CP-C ... /10#zoom=z


Or did you mean this one:

Image


this is the piston you can add as a choice



Also, updated my list with some new parts that I would love some thoughts on by your oldskeyltoy or jondee86.

Pistons:



Valve Guides:

Valve Stem Seals:

Valves:




STOP... breath....

1) Pistons: 30.5mm, or 1.201" = compression height. you don't want more, less can be dealt with. Fully skirt, you don't want a narrow, or partial skirt. Dome volume: minus .25cc should equal a smallport piston - avoid dome volumes larger then +2cc. You want the valve reliefs to match the valves... since you don't need oversize valves, you don't want pistons with oversize valve reliefs - make sure the piston you choose is designed around the valves you use.
2) do you know the valve guides are bad? In over 40 4AG heads, I've had to replace 2 guides... not 2 heads worth of guides... just 2 guides total.
3) Adding oversize valves gets VERY costly, and unless you are building something besides what you stated, are not needed. Stock Valves work fine on stock seats especially for this build level.


When it comes to the 4AG... no wiser words.....
jondee wrote:So if there is a lesson to be
learned it is to make sure all the components you purchase will work in harmony with
each other.
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby yabaiani » Mon Feb 17, 2020 8:01 pm

Breath taken sir. So question for you then, to simplify everything. What do you think about this option:

Red top pistons
MRP stainless steel valves - https://www.mrpltd.co.nz/product/4age-1 ... ves-0-5mm/
Stem seals
MRP connecting rods - https://www.mrpltd.co.nz/product/4age-b ... m-conrods/


And any thoughts on Matrix Garage pistons : http://www.matrixgarage.com/products/mg ... -largeport

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby oldeskewltoy » Tue Feb 18, 2020 10:30 am

yabaiani wrote:Breath taken sir. So question for you then, to simplify everything. What do you think about this option:

Red top pistons
MRP stainless steel valves - https://www.mrpltd.co.nz/product/4age-1 ... ves-0-5mm/
Stem seals
MRP connecting rods - https://www.mrpltd.co.nz/product/4age-b ... m-conrods/


And any thoughts on Matrix Garage pistons : http://www.matrixgarage.com/products/mg ... -largeport



Those oversize valves will work on stock seats, so the cost to use them is only the cost of the valves, and the cost of the valve job to fit them.... BUT, you would want to get a custom piston, as the Traums you listed are for std valves. You might be able to get the Traums opened up (custom fitted for 1/2mm oversize valves)

Again... you don't need oversize valves for your goals... a properly ported head will go a lot further.........
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby yabaiani » Sun Feb 23, 2020 6:42 am

oldeskewltoy wrote:
yabaiani wrote:Breath taken sir. So question for you then, to simplify everything. What do you think about this option:

Red top pistons
MRP stainless steel valves - https://www.mrpltd.co.nz/product/4age-1 ... ves-0-5mm/
Stem seals
MRP connecting rods - https://www.mrpltd.co.nz/product/4age-b ... m-conrods/


And any thoughts on Matrix Garage pistons : http://www.matrixgarage.com/products/mg ... -largeport



Those oversize valves will work on stock seats, so the cost to use them is only the cost of the valves, and the cost of the valve job to fit them.... BUT, you would want to get a custom piston, as the Traums you listed are for std valves. You might be able to get the Traums opened up (custom fitted for 1/2mm oversize valves)

Again... you don't need oversize valves for your goals... a properly ported head will go a lot further.........



As I am building everything, my engine will be built first, but with my cams, pistons, valves, etc will be before I install my ITB Kit from MRP. Can the stock JDM 16v ECU run the car ok? I also added a lightened flywheel as well.

My compression should be somewhere between 10.3:1 to 11.0:1.

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby oldeskewltoy » Mon Feb 24, 2020 7:07 am

yabaiani wrote: Can the stock JDM 16v ECU run the car ok?


"Ok" - a lot would depend on what ok actually means... but it should run on stock JDM management, how well is another story... The stock computer uses a whole bunch of different parameters(stock engine), you have changed many of those... so, it should run, but with an aftermarket ECU, you can optimize the tune - you can do more then the stock allows...
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby yabaiani » Mon Feb 24, 2020 8:52 am

oldeskewltoy wrote:
yabaiani wrote: Can the stock JDM 16v ECU run the car ok?


"Ok" - a lot would depend on what ok actually means... but it should run on stock JDM management, how well is another story... The stock computer uses a whole bunch of different parameters(stock engine), you have changed many of those... so, it should run, but with an aftermarket ECU, you can optimize the tune - you can do more then the stock allows...


I guess that was my question. Will there be any potential engine damage for driving around with a vehicle that is not properly tuned (not for very long), but am assuming at least 100-200 miles before the ITB kit and the standalone ECU is installed.

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby oldeskewltoy » Mon Feb 24, 2020 12:19 pm

yabaiani wrote:
I guess that was my question. Will there be any potential engine damage for driving around with a vehicle that is not properly tuned (not for very long), but am assuming at least 100-200 miles before the ITB kit and the standalone ECU is installed.


being 100% honest... I don't know...odds are there will not be a problem... but after spending thousands on a build... do you really want to experiment?
OST Cyl head porting, - viewtopic.php?f=22&t=300

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby jondee86 » Mon Feb 24, 2020 12:29 pm

yabaiani wrote:Will there be any potential engine damage for driving around with
a vehicle that is not properly tuned (not for very long), but am assuming at least 100-200
miles before the ITB kit and the standalone ECU is installed.

If you want to do that for engine break-in purposes, I would recommend that you
use stock cams rather than cams with increased lift/duration. The factory MAP ECU
uses manifold vacuum for load calculation and aftermarket cams typically don't make
as much idle vacuum as stock cams.

This means the engine will idle rich and run rich at low engine speeds as the ECU will
see the reduced vacuum as increased load and add fuel. This creates the possibility of
bore wash and impaired cylinder lubrication which is not what you want on a new engine.
Use the factory cams for break-in and change them out when you are ready to install
and tune with the ITB's and aftermarket ECU.

EDIT: The above comments are based on my experience with the cams I was using
with a factory MAP ECU. The PON cams are said to drop in and work with a factory
ECU, but I don't know if they are talking about a stock AFM ECU (should be OK) or MAP
ECU. The lift and duration of the PON cam is less than I was using so the affect on
manifold vacuum will be less. Probably worth a try... just keep the idle around 1000rpm
and check the AFR once the engine gets up to temperature.

I also recommend that you get your WBO2 gauge installed before you run the engine
so that you can check that the factory ECU is keeping your AFR within a safe range.

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby yabaiani » Mon Feb 24, 2020 4:34 pm

jondee86 wrote:
yabaiani wrote:Will there be any potential engine damage for driving around with
a vehicle that is not properly tuned (not for very long), but am assuming at least 100-200
miles before the ITB kit and the standalone ECU is installed.

If you want to do that for engine break-in purposes, I would recommend that you
use stock cams rather than cams with increased lift/duration. The factory MAP ECU
uses manifold vacuum for load calculation and aftermarket cams typically don't make
as much idle vacuum as stock cams.

This means the engine will idle rich and run rich at low engine speeds as the ECU will
see the reduced vacuum as increased load and add fuel. This creates the possibility of
bore wash and impaired cylinder lubrication which is not what you want on a new engine.
Use the factory cams for break-in and change them out when you are ready to install
and tune with the ITB's and aftermarket ECU.

EDIT: The above comments are based on my experience with the cams I was using
with a factory MAP ECU. The PON cams are said to drop in and work with a factory
ECU, but I don't know if they are talking about a stock AFM ECU (should be OK) or MAP
ECU. The lift and duration of the PON cam is less than I was using so the affect on
manifold vacuum will be less. Probably worth a try... just keep the idle around 1000rpm
and check the AFR once the engine gets up to temperature.

I also recommend that you get your WBO2 gauge installed before you run the engine
so that you can check that the factory ECU is keeping your AFR within a safe range.

Cheers... jondee86


Yes, I did the Tomei Poncams to just drop in since I didn’t want to do super aggressive cams...so I was hoping it would be manageable, but I may tow it to the dyno for the ITB Kit and standalone ECU install,

Thank you oldskewltoy and jondee86. Ill think it over and figure out the best think to do.

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jondee86
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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby jondee86 » Tue Feb 25, 2020 2:57 am

yabaiani wrote:Yes, I did the Tomei Poncams to just drop in since I didn’t want to do super aggressive cams...

Looking at the graphs for the PON cams they seem to be quite similar to some 261deg / 8.27mm
lift cams that I ran for a while some years back. The TVIS engine idled and ran just like stock on the
factory MAP ECU. The engine was otherwise completely stock with standard bigport compression.

The increase in power was barely noticeable in the low and midrange, but it did rev out nicely
and definitely had a better top end than stock. I think that they would have done more with
a bit more compression, and the PON cam graph also suggests that more compression will get
you a better result. So you are on the right track.

The general concensus is that 272deg cams are too long for the factory ECU. The engine can be
made to run but it won't idle and will run like a bag of excrement. Around 265deg seems to be
the longest cam that will run kind of OK, but fueling and timing will not be optimum. Running
an aftermarket ECU with cams is always a good idea :)

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

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Re: Newb question on how to guide for ITBs on JDM 4AG Bluetop w/ MAP

Postby Nick94tt » Tue Feb 25, 2020 2:29 pm

With the higher compression I'd dial back the timing a few degrees at minimum if you're planning on driving it hard to break in the engine. Ditto Jondee on the wideband, though that'll only tell you how far off you are. Without an adjustable fuel pressure regulator or fueling controls you're at the mercy of what the map ecu can do with your fuel setup. Even then, trying to adjust fueling like that on the street usually results in screwing up or a long and unpleasant encounter with the local police. :lol:

Honestly be more comfortable just towing it to the shop (or just leaving it there if you're not doing the assembly at home) and having them run the thing in on the dyno with the usual oil/filter change progression.

As deep as you are into this setup, I'd rather have it all together and at the tuner.

A lot of it comes down to which school of thought you are on break ins - Hard and fast vs extended progressive loading. Be a really good question for your engine builder/tuner.

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