how to improve the performance of 4G13 stock engine

LimauKanker

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LimauKanker

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webber, if do not have the know how tiuner near you... I don't think it will have any effect. worse are, high fc, no power.

having a 60whp (I guess for this islala), 80-90whp and 300whp.

my experiences of driving the 60whp to 300whp, I appreciate the latter more. but the earlier has more fun in cucuking. bcos the latter, unless the same fleet/category, otherwise people will say big bully. I used to 300whp, to me is underpowered. now having 60whp, then drive 300whp... wa wa wa... appreciate it so much.

touching up the islala bill up to date rm3k and counting. I guess another rm2k to go for interior clean up, radio up, and most taxing is the aircon. dem curse item in my fleet of cars.

I saw in mudah people selling islala with 4g61 N/A for Rm5k yet I'm spending rm5k just to purified the 4g13p, but the memories on this islala are simply priceless...
wow bro, what are you driving that is 300hp?
 

y2188

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y2188

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My Wira has changed to 4-2-1 extractor for RM265 and that one is worth my money I would say. The improvement in torque is very much noticeable and that is good enough for me. As for the midbox + 1.7 inch piping mod for RM220, that I can't feel much improvements other than perhaps slightly smoother RPM on higher revs. But for that one, the pipe mod was not a totally useless mod because my original piping is already heavily rusted with holes here and there. A lot of weld patching was done to it before this and by the looks of it, the original piping can't last much longer until another crack or hole appears. So, instead of going for stock piping, I just go for that 1.7 inch piping + midbox. As for rear muffler, I am using stock Wira 1.8 twin tip muffler. I don't bother about changing to aftermarket muffler because of the noise they make and from what I think, if the twin tip muffler was already designed to allow the higher volume of exhaust gas flow for the larger 4G93 engine, it is good enough for my stock 4G15 engine exhaust gas flow. Exhaust sound was almost same as stock exhaust during idling, just when I rev it, the sound is a bit sportier.
You should've gone for 2" piping
 

LittleWhiteWagon

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LittleWhiteWagon

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good morning,

i know it is an old thread that i dug out but just dont want to restart any new thread as basically it is same. yes, now is 2018, im taking over a 1994/1995 Iswara A/B manual gear, with 4G13P as it heart ever since. it has done top overhaul few years back to fix up the white smoke and the engine oil reduction/top up issue.

objectives:

1. better performance without cost of an arm or leg, understand that each HP come with dollar n cent, let's work around Rm3k +/- as budget, just for the engine enhancement.

2. not overenthu toward changing engine as finding 4G61 which is very old engine reliability/condition of it, 4G9x/sohc/dohc/mivec need to alter/mod the engine mounting. as uncle that going thru mid life crisis, really do not have the patience to let the car sit in workshop more than i'm driving it.

3. using it as town driving and if condition allow, do not mind some distance driving like jb-kl, tahan in jam for hours, etc.


now, my questions are below, really appreciate the kind wording from any of you that have done it, been there, learn it, etc that so kind of you taken your precious time to read up and answering (if you can).

1. 4G13P can fit in 4G15P block assuming the head is the same (correct me if I'm wrong), will the oem piston/conrod too small for 4G15P block? If yes, meaning to say need to find the full set piston/conrod? are they sharing same crankshaft, bearing, etc?

2. If chose the option of 4G15P block, internal enhancement on piston/conrod/crankshaft of 4G18P, this will need to bore the 4G15P block, if running on high rpm, which i usually do bcos the other car im driving is turbo, hence my driving style will always high rpm and turbo kick and the g-force feel, of course not applicable in this 4G13P but still wanted to ask whether such stroker kit + my driving will eventually crack the block or my head 1st. Yeah, this Q defying my objectives, but really wish to know what's the outcome. Thanks.

3. Current gearbox, hmmm... can engaging gear but at times it feel like the box wanted to drop off... to solve this, by overhaul the gearbox?

4. Performance Carb, after some reading it seem like if no patience dont go for it as a lot of tuning/tweaking needed. If so, finding 4G15P block + EFI will be better option, as OEM carb engine, if add on EFI, extra wiring + ecu needed, hence will it be extra headache? or stick to oem carb, anything to do to for enhancement?

5. This car really like an old man on ciggarettes for long long time, each morning wake up, it will choke as if engine dropping off until it warm up, relatively acceptable level. It can't immediately action like drop off pant and viola, and need long foreplay (too long in my opinion) before actual action. Read up some, it says carburetor, fuel line, spark plugs, distributor, etc, really would like to rectify this.

6. Clutch... is due... overdue actually... any recommendation?

7. Brake, if enhancement done, this need to relook as safety 1st always important. I lurked around saw Nissan brake servo double layer pump can PNP, is it better than oem servo? or just add on the brake booster pump? I have bad experience taking over those bigger brake kit from half cut, etc... it jammed and lots of headache.

8. Lastly, i'm from JB, hence those recomendation has to be done in JB. Any highly recommended, trusted, reputable and done before such trivial modification really appreciate your kind gesture to inform me.

Finally, to sell the car, it do not worth much. to fix it up, run errand, go deeper inner road for trial/jungle runs, bike racing, dirt plantation, will be good using such car of course reliability as well, as stranded in middle of nowehere really no eyes see...

thanks in advance for your kind inputs
Regarding the engine question, yes the 4G15 block should bolt on to the 4G13 head just fine. If you can get a block where the head studs are Allen Key type it’s also a bit better, studs are slightly larger so you have a bit more clamping force.

If you want just a bit more pep for the car you can just do the combo of what the guys said: Waja crank, 76mm FLX/BLM pistons, and a 1mm head gasket. The compression ratio you’ll get will be somewhere within the high 9’s or low 10’s depending on your head whether it’s been skimmed and modified in the valve area. Good thing about this is you can run ron95 with no issues... I would suggest just slightly porting the head more to the exhaust side & lightening the flywheel to have a bit of fun. Once your ignition timing & fueling is settled the car will be pretty fun to drive. I would suggest an adjustable cam gear also to adjust your powerband where you’d like it to be.

If you’re itchy for a bit more power a mild cam is pretty fun also but slight cost of FC and bottom end power.

For exhaust just go for a full 2” from extractor till the rear. If you want even more power you can get a thinner HG and more aggressive cams and pistons & a 2.5” exhaust, bit you’ll definitely run into fueling and timing issues at this level... efi would be a lot more ideal but that’s $$$$. Don’t bother listening to Renesis’s theory about 4-2-1’s being for ‘pickup’ and 4-1’s for ‘top end’, it’s not so general. Generally the typical off the shelf 4-2-1’s work fine, just match the diameter from front to back and you’ll be fine... and stay away from S-flow mufflers.


For brakes just change your front calipers to perdana calipers and discs, leave the booster and cylinder alone. It feels very very nice, stops hard too.
 

RENESIS VIII

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RENESIS VIII

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lol then whatever floats your boat man. if the car meant so much for you, then just dont bother modding it is the best choice, then again, you're also not learning anything if you never go thru all this stuff.
The mods I am doing are just minor mods which improves the original characteristics of the car. I would say even FC improved a bit from the exhaust mod. So, there isn't any downside to those kind of mod. If I want to go for serious high performance mod, I will pick another car, not this one.

Your car runs on "pilot jet" normally, the secondary needle u talked about its called "main jet". Nice display picture by the way, can intro?
How to intro,not somebody that I know, lol.

You should've gone for 2" piping
Too big for my stock engine. Might loose pressure if I go 2".
 

LimauKanker

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LimauKanker

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The mods I am doing are just minor mods which improves the original characteristics of the car. I would say even FC improved a bit from the exhaust mod. So, there isn't any downside to those kind of mod. If I want to go for serious high performance mod, I will pick another car, not this one.

Too big for my stock engine. Might loose pressure if I go 2".
idk man, you're the mod car sifu. why 2" loose pressure tho?
 

RENESIS VIII

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RENESIS VIII

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To, Firezy, in case someone earlier misquoted me for something that I did not write or say in this thread, do ignore that statement as I did not write anything stating about 4-2-1 for pickup and 4-1 for top end over here.
"Don’t bother listening to Renesis’s theory about 4-2-1’s being for ‘pickup’ and 4-1’s for ‘top end’"


idk man, you're the mod car sifu. why 2" loose pressure tho?
The piping diameter is too large where exhaust gas might cool down faster where it might affect the gas flow speed to exit the piping.
 
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LittleWhiteWagon

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You should've gone for 2" piping
To, Firezy, in case someone earlier misquoted me for something that I did not write or say in this thread, do ignore that statement as I did not write anything stating about 4-2-1 for pickup and 4-1 for top end over here.
"Don’t bother listening to Renesis’s theory about 4-2-1’s being for ‘pickup’ and 4-1’s for ‘top end’"




The piping diameter is too large where exhaust gas might cool down faster where it might affect the gas flow speed to exit the piping.
Want me to screenshot when you’ve said it? You already said it in the vios thread earlier this month... you didnt say it over here but you’ve said it before in other threads. It’s getting kind of old la.

Btw pls go out and get some experience IRL. It’s 2018, 2” isn’t too big.

I dare you to run 2” and grab your exhaust tips after driving and say the gas flow cools down ahaha.

Next you’ll probably give a chart of what piping size to HP to follow... but since you can feel a lot of stuff, how do you determine exhaust sizing for cars?
 
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RENESIS VIII

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RENESIS VIII

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Want me to screenshot when you’ve said it? You didnt say it over here but you’ve said it before in other threads.

Btw pls go out and get some experience IRL. It’s 2018, 2” isn’t too big.

I dare you to run 2” and grab your exhaust tips after driving and say the gas flow cools down ahaha.

Next you’ll probably give a chart of what piping size to HP to follow... but since you can feel a lot of stuff, how do you determine exhaust sizing for cars?
In case you missed the fine print, I did mention that this is not something that I write or say in this thread. Feel free to screenshot what I said it in other thread if you want.

Go out and get some experience IRL? Now that is quite an assumption that you are making there but it is up to you on what you want to think about me.
 
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LittleWhiteWagon

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To, Firezy, in case someone earlier misquoted me for something that I did not write or say in this thread, do ignore that statement as I did not write anything stating about 4-2-1 for pickup and 4-1 for top end over here.
"Don’t bother listening to Renesis’s theory about 4-2-1’s being for ‘pickup’ and 4-1’s for ‘top end’"




The piping diameter is too large where exhaust gas might cool down faster where it might affect the gas flow speed to exit the piping.
In case you missed the fine print, I did mention that this is not something that I write or say in this thread. Feel free to screenshot what I said it in other thread if you want.

Go out and get some experience IRL? Now that is quite an assumption that you are making there but it is up to you on what you want to think about me.

Well I’m glad you can point that out. I’m also giving people a heads up to take your advice with a general pinch of salt cause you just glazed over the rest of what I asked. You use butt feel and theories which are amusing.

Oh don’t worry, it’s not an assumption. You’re pretty vocal enough to show people how little you’ve experienced... but it’s quite fun la reading about you getting your first extractor. Don’t spray paint it ya haha.
 
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Hi, long time lurker, first time poster. It's 2018 and people are still doing the whole "4-2-1 for mid range and 4-1 for top end"? Properly designed 4-2-1s that can fit within space constraints are always better, and tuned for the right operating rpm range they make more torque and more power. Picking badly designed 4-2-1s to go against relatively generic but higher flowing (by accident) 4-1s is cherry picking data.

Oh lord, here we go again with backpressure. Welcome back to the 1990s, when internet was dial-up and information was misinformation.
 

RENESIS VIII

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RENESIS VIII

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Well I’m glad you can point that out. I’m also giving people a heads up to take your advice with a general pinch of salt cause you just glazed over the rest of what I asked. You use butt feel and theories which are amusing.

Oh don’t worry, it’s not an assumption. You’re pretty vocal enough to show people how little you’ve experienced... but it’s quite fun la reading about you getting your first extractor. Don’t spray paint it ya haha.
From your detailed description in your posts, indeed you are the one with more experience in 4G15 modding. You are right, about me using butt feel and theories which are just solely my own baseless assumption. As a person without any true hands on experience at all, I advice every one here to take what I said with a pinch of salt. I guess a keyboard warrior like me who only types and writes but without any real knowledge about cars should just be more quiet when seniors are giving out helpful advice.

A very well write up there earlier. It finally cleared some of my clouded thoughts and misconceptions about modding a 4G15. Thank you very much for your detailed explanation earlier as it enlightens with more knowledge about engine modding. I admit that all that I have said earlier are just misguided wrong information which was all made up by myself.
 

LimauKanker

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LimauKanker

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walao eh.. i heard from people that i can find the one true master RENESIS here. i purposely risk my life, climb mountain, swim river, login zth from office pc just to learn from RENESIS sifu.. now he say he duno anything out of no where. :emoji_disappointed_relieved:
 

parakey

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parakey

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walao eh.. i heard from people that i can find the one true master RENESIS here. i purposely risk my life, climb mountain, swim river, login zth from office pc just to learn from RENESIS sifu.. now he say he duno anything out of no where. :emoji_disappointed_relieved:
Perhaps tone it down. Dah cukup already
 
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LittleWhiteWagon

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From your detailed description in your posts, indeed you are the one with more experience in 4G15 modding. You are right, about me using butt feel and theories which are just solely my own baseless assumption. As a person without any true hands on experience at all, I advice every one here to take what I said with a pinch of salt. I guess a keyboard warrior like me who only types and writes but without any real knowledge about cars should just be more quiet when seniors are giving out helpful advice.

A very well write up there earlier. It finally cleared some of my clouded thoughts and misconceptions about modding a 4G15. Thank you very much for your detailed explanation earlier as it enlightens with more knowledge about engine modding. I admit that all that I have said earlier are just misguided wrong information which was all made up by myself.
I wouldn’t say everything you post is 100% wrong, but it’s very generalized. I would suggest trying out more stuff on your own car so you can use more updated info for your posts in the future.

The reason why I left that line there is so that if people do come across this and want to copy the setup there’s room for them to think as well instead of just applying outdated theories for headers. There’s still room to improve and update your theories.

But regarding the write up, you’re welcome. I hope the info was useful to whoever comes across it. I also have this stubbornness to stick to the 4G15 so I’m willing to share a very very vague guideline of what works. There’s still a lot of specifics I didn’t mention because I myself have no experience with it.

And just remember la, you’re a very vocal person. It’s hard to hide when you’re prominent... it’ll be nice if you keep the forums alive with accurate information.