For those who don't know my setup, I'm running 12:1 compression Wiseco pistons with Eagle rods, W41 HG2 cams (.430" and 224*) and 2.5" ehxaust. Going down the strip is a shame. Got a best of 16.3 at 80mph ( I let off before the line) and even with holding it I can't get faster than 84 mph. NO tire spin, the car doesn't have enough power to make them spin. The engine was almost stalling even with reving at 5k.

I was doing a bit better last year with 3.5 cylinder

So now I don't know if it's because the cams need to be timed differently or if I need more tuning on the chip.

The best run was done on a stock 92 Scx chip. BAKS. Even at 7k the car doesn't have much power. At 8 000rpm it feel the same at 7k. There's a big gain of power at 5000 because of the cams but after that it doesn't seem and it's not fast.

So Todd (really looking for your help) , Brian (all of them), Chris and all the 2.3 guys, I need your help.

I sold all of my Ho cams and I'm looking to get another set to see how the engine will react with smaller cams. Cammed idle is nice but not worth the big lost of power.


Gilles
2.3 Ho

Wow...that sucks Gilles. Do you have any idea what kind of overlap the HG2's have? How much total advance are you running on what octane?

Also, I don't know what size TB you have, but if it's the stock 56 mm, you might want to invest in something a little larger (maybe a larger exhaust too), as it sounds like your starving the top end.

Lastly, have you done a compression check recently?


-

"Youth in Asia"...I don't see anything wrong with that.

what MV is it at? i dont think timing is a problem. to much fuel... what kind of exhaust?

because the motor is less effesent below, say 4500, PE should be redused, stay the same alittle higher, and incresed topend. some time with a scan tool and a wide band will help get it diled in. Email me your .bin's and def files.

Chris


'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08

I still have the cam card if you want the numbers. I don't have a definition file for the bin I have. I had somebody burned me a few chips. The one I did the best time is the stock W41 chip. The modified chip I was running has 10* less in PE cause I have alot of problem with knock and misfire when it's cold outside. When it's hot outside it's fine.

I still have the same Tb but it shouldn't be enough to slow down the car almost a full second slower than the stock engine. I was running 15.5 at 92mph when I had the stock engine.

A 2.5" mendrel bend exhaust cut in front of the back tire should be plenty for that engine.

The last compression test I did was last spring before starting the car. I could do another one to be sure. In case you are wondering, it had 285psi of compression.

I am running a mix of 91 and 94.

I don't have a wideband. Just a narrowband being well on the rich side.


Gilles
2.3 Ho

HMMMM hows it run on the W41 PROM? if it where mine, i would copy\past the fuel cells from your moded .bin, and use the timing from a OE BAKS.

are all the sensors OK? wonder if it could be a crapy knock sensor\ MAT sensor.

BUT, even with my 10.5:1 flat top pistons, the Rocket parts tune Knocked... i could hear it. sounded like marbles on the top side of the motor.

you dident deg the cams did you?

Chris


'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08

The cams are set to 0. The fuel is not suppose to be changed on the chips I have. All the sensor seem ok unless the knock sensor is seeing the cams as knock. When it knock when the temperature outside is cold, it's run like in batch like the idle and you can hear it knock. Kinda like a big hammer hitting the engine.


Gilles
2.3 Ho

maybe you need to degree the cams

that sucks , its running worse

Compression is good. I just checked it.

I don't feel like spending hours after hours on the dyno trying to time those cams. Also, the adjustable gear are pretty gone. I need to make my own.


Gilles
2.3 Ho

Does it feel kinda like a kick in the nads? Running slower than you did stock? I sure hope so. BUT DON'T GIVE UP!!!!!! Keep at her man, you will figure it out. It is absolutely impossible to have less power than you did before as long as you upped compression, have a higher flowing intake and exhaust, getting the right amount of fuel, and your cams are cooperating.

Quote:

I don't have a wideband. Just a narrowband being well on the rich side.

Please, Please, please, at least by a wideband O2.

I dont know how you can even think of burning new fuel maps if you dont really know where you are now?

My guess is you are running really rich, with the specs on your motor you should have tones of power.

As well, if your going to tune this thing propperly, the cheap way is to do a street tune with a wide band, the expensive way is to hit the dyno. I would hit the dyno for a couple runs just to verify your street tune.

Have you considered maybe getting a stand alone? Even Megasquirt? I dont see how burning chips is going to be accurate based off a narow band reading.... you will be guessing.




"Go Before Show Yo."
CARCUSTOMS.NET, THE BEST SERVICE ON THE ORG!!!

bmxludwig wrote:Does it feel kinda like a kick in the nads? Running slower than you did stock? I sure hope so. BUT DON'T GIVE UP!!!!!! Keep at her man, you will figure it out. It is absolutely impossible to have less power than you did before as long as you upped compression, have a higher flowing intake and exhaust, getting the right amount of fuel, and your cams are cooperating.

Yes it's a big kick in the nuts. I'll figure it out. The first thing I'll hit is the knock sensor. I have a second one so I got some testing to do. Cam timing is the essential but $$$$$ .

Quote:

Please, Please, please, at least by a wideband O2.

I dont know how you can even think of burning new fuel maps if you dont really know where you are now?

My guess is you are running really rich, with the specs on your motor you should have tones of power.

As well, if your going to tune this thing propperly, the cheap way is to do a street tune with a wide band, the expensive way is to hit the dyno. I would hit the dyno for a couple runs just to verify your street tune.

Have you considered maybe getting a stand alone? Even Megasquirt? I dont see how burning chips is going to be accurate based off a narow band reading.... you will be guessing.

As for the fuel, it would be leaner, not richer. Using stock maps and injectors, there's no reason it would be richer. The engine seem to be on the perfect side for fuel. The plugs are clean. The base as a bit of black but the rest is like a new plug.

Using a full stand alone system for a set of cams and 2 points more of compression? You sure dont know much about burning chip. It's the same thing and just as accurate.

Also, there is no freakin way I'm going to be doing WOT pull on the street. I'm not dumb enough for that.




Gilles
2.3 Ho

Quote:

As for the fuel, it would be leaner, not richer. Using stock maps and injectors, there's no reason it would be richer. The engine seem to be on the perfect side for fuel. The plugs are clean. The base as a bit of black but the rest is like a new plug.

Using a full stand alone system for a set of cams and 2 points more of compression? You sure dont know much about burning chip. It's the same thing and just as accurate.

Also, there is no freakin way I'm going to be doing WOT pull on the street. I'm not dumb enough for that.

Ok...... according to what you have said you are using a narrow band o2. How can you expect to get a propper air fuel reading with this? You need to buy a wide band. Your right I dont know alot about burning chips but how do you expect to know where your air fuel is without putting it on a dyno or at least buying a wide band o2 sensor.

Wot pulls on the street? OMG! You just said that you went to the drag strip?! You would have accurate data logs already and you would KNOW where your fuel is exactly from your runs on the strip if you had a wide band. Im sorry, looking at the color of a spark plug does not replace air/fuel numbers.

Quote:

Using a full stand alone system for a set of cams and 2 points more of compression? You sure dont know much about burning chip. It's the same thing and just as accurate.

Im using a TEC3R for my High comp build because I dont want issues where im guessing whats wrong so I would say its worth it.




"Go Before Show Yo."
CARCUSTOMS.NET, THE BEST SERVICE ON THE ORG!!!

Sounds like your in the same boat as Paul (N/AMadness)......

I'd double check the cam timing (just to make sure its on, not one tooth off either way), a wide band would be a great thing to have.

Its hard to say what the issue would be, hard to diagnose over the internet.




SPD RCR Z - '02 Z24 420whp
SLO GOAT - '04 GTO 305whp
W41 BOI - '78 Buick Opel Isuzu W41 Swap

Thanks Brian. I was thinking about the timing too. Those pistons have relief for alot of lift so the timing could be off a bit without causing trouble. The other thing I was thinking would be the knock sensor seing false knock because of the cam.

My other idea would be valve float because of the lift. I have some stronger spring that I can use but I need the base to hold them in place.


Wideband would be nice but if somebody has 300$ to give me to get one, go ahead.


Gilles
2.3 Ho

I had a tought that maybe the spark is not strong enough with that compression and high rpm. The 2.2 coil swap would be a good thing.



Gilles
2.3 Ho

Does it feel like its mis-firing? I can feel it when my car does it.

It just seems like the timing is one tooth off or something, if you have no real power at all.

Keep your eyes pealed on Ebay for a wideband.... I've seen them go pretty cheap some times (I did drop $300 on my PLX one though)

If you can get your hands on a OBD-1 scan tool, you can keep an eye on the Knock counts, and Timing....... would help in ruling that out.




SPD RCR Z - '02 Z24 420whp
SLO GOAT - '04 GTO 305whp
W41 BOI - '78 Buick Opel Isuzu W41 Swap

I am going to lean towards cam timing.

When I did the w41 slowfire swap, we went from over 250hp to 160hp with the cams installed at "zero" per the GM setup locations. qtr mile times suffered equally.

I did not have time or tools to properly check to see if they were degree'd in. Instead I took the easy way out and changed them back. But I am fully conviced that they were mis-degree'd. I have never had an opportunity to remove a set from a running engine to check if they were installed "correctly" or not from the factory.

sig not found

ive never understood 'degreeing' im sure im missing something, here but dont the cams just go in one way, you put a line up bolt through the cam gear and into the timing cover and it aligns the cams... correct?

idk, i just dont understand the whole thing, its basically the only thing i havnt done to a 2.4 yet.

Could you post what the cam card says? It would be a big help in my quest to get that info for desktop dyno.

Also, what were the exact compression test numbers? Sortta wondered as my built quad is at 11:1 and was pushing 250-260 psi.





13.934 @ 97.82 ALL MOTOR

protomec wrote:When I did the w41 slowfire swap, we went from over 250hp to 160hp with the cams installed at "zero" per the GM setup locations. qtr mile times suffered equally.

I remember that. When I pull my W41 apart, I will take a look at the cam gear to cam relationship.




SPD RCR Z - '02 Z24 420whp
SLO GOAT - '04 GTO 305whp
W41 BOI - '78 Buick Opel Isuzu W41 Swap

because the stock air box is ugly and i dont want to pay $200 for a real intake

lol

i dont know how that post got into this thread but disregard it, it was meant for another thread sry

z yaaaa wrote:ive never understood 'degreeing' im sure im missing something, here but dont the cams just go in one way, you put a line up bolt through the cam gear and into the timing cover and it aligns the cams... correct?

idk, i just dont understand the whole thing, its basically the only thing i havnt done to a 2.4 yet.

a cam is designed to work in specific time with the rotation of the crank.
Since the crankshaft is rotating, the rotation is measured in degrees... 0 to 360. Because it is measured in degrees, timing of anything related to it, ignition timing, cam timing, balance shaft timing, etc, are also expressed in degrees.

The camshaft is designed to open the valves at specific degrees of crank rotation. Altering the timing of the cam can gain/lose power and change the rpm band the engine makes that power.

Factory engines are generally designed to accept a wide range of timing from its intended cams, chains/belts/gears, and sprockets. Performance engines are usually very specific to locate the timing of these parts exactly where they designed to be.
The process of checking and setting this up is known as degreeing the cam. To do it correctly, specific information needs to be known about the cam... valve opening and closing points, or valve lift centerlines. Then you can check to see if its where its supposed to be and adjust accordingly if its not.

Almost all cams will be timed correctly if the factory marks and locators are used. The biggest usual concern on OHC engines is a change in deck height or head thickness (decked block, different thickness head gasket, milled head). This will change timing because the distance from the crank to the leading edge of the cam sprocket has gotten larger or smaller rotating the cams to take up the change. this can be checked and corrected with adjustable gears and such.

A bigger possible problem though, and the one I think is happening here, is when differently designed parts are used together. GM may have used cam gears with differently located cam pin or line up hole locations on some w41s. Or they could have put the pin in the cam in a different location. Or even yet, they may not have used the guide pin location to align them at all.
There is no way to know without "degreeing the cam".

For this situation, really specific specs aren't required. Almost all factory cams have an intake centerline of 112 to 114 degrees. If its checked and its 8° or more off, then something specifically different was used.

Back to the changing the powerband issue. The W41s in the slowfire made only 168hp @5800rpm but it also made 285lb-ft @2k. This screams that the cams were many degrees off even though all the stock "marks" were lined up.

sig not found

wow, great explantion-thanks man!

(sorry to jack, mfk)

im hopefully going to be running a HO exhaust cam and either an LZM stage 2 intake cam or a JBP stage 2 intake cam along with it. do you think i'd be ok just using the stock 2.4 cam sprokets and line up holes etc? or would it be a must to degree them? my dad has a moroso degreeing wheel for use in v8's... would i even be able to use this, or what?? what should i do..?

also, the head i'll be using was decked .002, i doubt that would a difference tho... or would it?

Todd - thanks for the explanation. I remember the timming being off by maybe 2-3 degrees on the crank. The cam gear were locked and the crank had 2-3 degrees more to take the slack of the chain. The chain is new so I know it's not stretch.

So if I understand you right, I would need adjustable cam gears so that I can set the crank right then adjust the cam. The cams are from Comp Cams. They had the same spec has the Crane cams.

I'll check to see if the gears I have now are the same as the OEM. I bought a timing set from Fel-Pro but I remember seeing people on Q4forum saying the OEM gears had different settings on them. IE the locator hole was placed differently on the intake and the exhaust gear.



Brian - The car doesn't seem to misfire. It has some power but not much. 3rd gear has NO POWER at all. There's 10* retard for now in PE mode on the chip I'm using. But even a stock W41 chip doesn't give much more power.



The compression is at 250psi on all 4. I'm sure tough that it was higher than that before.


Gilles
2.3 Ho