# Boosting w/ stock injectors and MAF



## dreadsword (Dec 2, 2002)

Just wondering - according to other threads, the stock injectors are 197's, and should max out around 115 whp. That is to say, can't really boost with these injectors. That being said, has anyone done it?

It would be great to get low-psi boosted for the summer (i.e.: 5 psi, via Hallman MBC), which I'm in a position to do. I can't, however, afford to do the MAF/Injectors/JWT upgrade at the same time.

So - are the above numbers right? Has anyone successfully boosted an otherwise stock GA?


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## NotAnotherHonda (Aug 7, 2003)

if you wanna boost without going over 115whp, it would prolly work...


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## chimmike (Oct 17, 2002)

if you can't afford to do it right, don't do it at all. Thats the best advice that can be given.


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## dreadsword (Dec 2, 2002)

Fair enough, chimmike, but there is something to be said for a staged upgrade program, as are available on many cars with superior aftermarket support. What I'm trying to figure out is if the stock GA16 injectors can support *any* kind of upgrade, or if they're maxed already. 

I know the MAF will meter up to 7psi (as experienced by NPM), so it stands to reason that the injectors and MAF would be in sync in terms of their capabilities. However, discussion elsewhere in this forum seems to indicate that this is not the case.

So -- seeking clarification.


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## NotAnotherHonda (Aug 7, 2003)

dreadsword said:


> What I'm trying to figure out is if the stock GA16 injectors can support *any* kind of upgrade, or if they're maxed already.


.

maybe im not understanding, but if an injector maxes out at about 115whp, it means that it can only support up to 115whp...i dont see the problem...am i not getting something? sorry 

you cant go and dump on a turbo on stock injecotrs, but you "can" with a MAF...thats what im doing now, until i can afford another JWT ECU upgrade...


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## dreadsword (Dec 2, 2002)

Not sure I follow you, notanotherhonda.

What I'm asking is, who has "real world" experience with these injectors? Is that 115 whp number substantiated? I got that from someone's calculations, but those same calculations showed that 370's were maxed at 218whp .... which they clearly aren't. So - is "115" just a number?

Now - your turbo - you're using a JWT ECU with the stock MAF and 370CC injectors? Do I have that right?


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## aminidab (Apr 30, 2002)

> What I'm asking is, who has "real world" experience with these injectors? Is that 115 whp number substantiated? I got that from someone's calculations, but those same calculations showed that 370's were maxed at 218whp .... which they clearly aren't. So - is "115" just a number?


The 115 hp is just a calculation, an estimate. I'm sure you could get more than 115hp out of the stock injectors, maybe 125, 130? I don't think anyone has a dyno running the stock injectors with more than 120 HP though.


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## NotAnotherHonda (Aug 7, 2003)

dreadsword said:


> Now - your turbo - you're using a JWT ECU with the stock MAF and 370CC injectors? Do I have that right?



yep...


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## dave_f (Dec 11, 2002)

its an estimate that takes in to account a very fat duty cycle.... I would be very leery about running injectors near 100% duty cycle. especially without a way to monitor it.
-dave



aminidab said:


> The 115 hp is just a calculation, an estimate. I'm sure you could get more than 115hp out of the stock injectors, maybe 125, 130? I don't think anyone has a dyno running the stock injectors with more than 120 HP though.


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## aminidab (Apr 30, 2002)

dave_f said:


> its an estimate that takes in to account a very fat duty cycle.... I would be very leery about running injectors near 100% duty cycle. especially without a way to monitor it.
> -dave


Yeah if you wanted to do this it would be a good idea to have a means of monitoring the A/F ratio, either a A/F gauge with a wideband O2 sensor or an EGT gauge. That would add some $$. 
It would be interesting to see where the stock injectors really max out at though.


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## NotAnotherHonda (Aug 7, 2003)

aminidab said:


> It would be interesting to see where the stock injectors really max out at though.


yea, cause if i bought my 370's for nothin, im gonna be pissed hahaha


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## chimmike (Oct 17, 2002)

aminidab said:


> The 115 hp is just a calculation, an estimate. I'm sure you could get more than 115hp out of the stock injectors, maybe 125, 130? I don't think anyone has a dyno running the stock injectors with more than 120 HP though.



why would you want to try this? Honestly? When you can get stock sr20 259cc injectors for like $50....................honestly?

I think its stupid to try and push the boundaries of injectors that will probably only support that 115whp.........which is what, full bolt ons and head work?


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## aminidab (Apr 30, 2002)

> yea, cause if i bought my 370's for nothin, im gonna be pissed hahaha


Well I assume you're looking to put out a lot more than 115 HP...



chimmike said:


> why would you want to try this? Honestly? When you can get stock sr20 259cc injectors for like $50....................honestly?
> 
> I think its stupid to try and push the boundaries of injectors that will probably only support that 115whp.........which is what, full bolt ons and head work?


Hey it's his idea not mine, but with new injectors he couldn't use the stock ECU, which means a lot more than $50.


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## dave_f (Dec 11, 2002)

aminidab said:


> Yeah if you wanted to do this it would be a good idea to have a means of monitoring the A/F ratio, either a A/F gauge with a wideband O2 sensor or an EGT gauge. That would add some $$.
> It would be interesting to see where the stock injectors really max out at though.


A tectom will also record peak injector pulse width. You just have to back calculate the duty cylce with engine RPM. I'm guessing you can toast your engine in the time it takes you to punch those numbers into your calculator. I think the general consenoius is :run properly sized injectors for your application (whatever that may be 115hp, 200hp, 300hp... etc). 
-dave


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## chimmike (Oct 17, 2002)

aminidab said:


> Well I assume you're looking to put out a lot more than 115 HP...
> 
> 
> 
> Hey it's his idea not mine, but with new injectors he couldn't use the stock ECU, which means a lot more than $50.



Well, I was running 310cc injectors in my car for a few days without any adjustments. Sure, it ran rich, but after like 6 days it started to get used to the injectors and lean them out a little bit........the car felt peppier. if you're running turbo anyways, you better be using some sort of management.


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## wes (Apr 30, 2002)

This is pointless. Don;t even try to boost your car on stock injectors. I believe in the staged upgrade program but this is NOT the way to go about it. Start out with at least 370's and a stock MAF. Hell just get the 240 MAF since they can be found pretty cheap. Your going to want to run the JWT ecu anyway so just save your $$$ and do it right one time rather than being impatient and frying something because you boosted on the stock injectors.

FWIW Mike Saiki's car made 119 WHP on the stockers so they have supported at least that in a real world application. You will have to run less than 4 PSI to make this run even close to safely, problem is not even the factory wastegate can be adjusted that low. 

Like I said a waste of time and $$$


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## dreadsword (Dec 2, 2002)

Hey Chimmike - I think it was aminidab that captured my point. Injectors? Cheap. JWT ECU? Not cheap. For me up here in Canada, it'll be prolly close to $1000 CDN. So - point being, if there's a "Staged" option I'd take it and run it low boost if I could do safely for a year. However, consensus appears to be that the stockers are to close to maxed as is.

FYI - I've got bits and peices of this setup all over the place here - including a 95 240SX MAF, Starion IC, 95 SE-R TB, etc. Injectors wouldn't be a problem to get a hold of, but I won't be able to afford the manifold/DP *and* JWT ECU both in the same season --- so looks like I'll keep on waiting.


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## dreadsword (Dec 2, 2002)

Wes - it wouldn't be a waste of time or money if the stage concept worked on our motors. That being said, this doens't appear to be the case (thanks for your input!), so like I said in my last post - I give up (for this year!). Unless JWT has a garage sale.


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## NotAnotherHonda (Aug 7, 2003)

just save up every day...its not that expensive... well...

its worth it in the sense that it doesnt cause headaches down the road...its plug and play of course, and it is certainly easy to use...

go with whats tested...use your 240 MAF, 370's, and jwt ecu...youllbe glad you did


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## chimmike (Oct 17, 2002)

dreadsword said:


> Hey Chimmike - I think it was aminidab that captured my point. Injectors? Cheap. JWT ECU? Not cheap. For me up here in Canada, it'll be prolly close to $1000 CDN. So - point being, if there's a "Staged" option I'd take it and run it low boost if I could do safely for a year. However, consensus appears to be that the stockers are to close to maxed as is.
> 
> FYI - I've got bits and peices of this setup all over the place here - including a 95 240SX MAF, Starion IC, 95 SE-R TB, etc. Injectors wouldn't be a problem to get a hold of, but I won't be able to afford the manifold/DP *and* JWT ECU both in the same season --- so looks like I'll keep on waiting.




Like I said before though, if you have no form of engine management, you shouldn't be running a turbo setup, or even just larger injectors. Stuff like this isn't cheap to do.


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## morepower2 (Apr 19, 2002)

chimmike said:


> Like I said before though, if you have no form of engine management, you shouldn't be running a turbo setup, or even just larger injectors. Stuff like this isn't cheap to do.


Yes, if you can't afford engine managment, you can't afford a turbo. You'll just end up doing even more expensive damage.

Mike


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