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my dad and i have been thinking about doing up one of my 5m heads. it seems the ports are really good, but maybe too big for the valves. can you go with bigger valves? the stock ones are already a decent size so idk.
 

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yes i had 1mm on mine and wow but i sugest getting a cam if you do this

you will also need to port polish head 210 injectors piggyback and 3 inch intake with a modified afm and a enlarged intake if you want to get all that power
the power difference is amazing

you will be amazed by the power lol
 

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Something like a safc!!!
thanks scott
yes and adjustable cam gears you will have a amazing jump in hp then tune.
Guys im thinking with this type of setup you would achieve 15 to 25 rwhp what do yall think? And lets say with advanced timing.
 

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yes i had 1mm on mine and wow but i sugest getting a cam if you do this

you will also need to port polish head 210 injectors piggyback and 3 inch intake with a modified afm and a enlarged intake if you want to get all that power
the power difference is amazing

you will be amazed by the power lol
Personally I don't agree with the other requirements. I probably wouldn't even invest in oversized valves unless I damaged some. Just adding oversized valves will not mean you need to buy all that other stuff too. I'm sure that most of them would build more power together, but by the sounds of it, he is only guessing. Why add a SAFC or bigger injectors? I'd be surprised if you maxed out the AFM and it wasn't able to keep a good A/F. Sure tweaking is nice, but just adding a set of cams, OS valves, and a better intake/exhaust likely won't require Fuel system modifications. Plus how would you tell if you are doing good with the SAFC with a wideband or dyno tuning?
 

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Im just taking it to the extreme. lol This setup would be a cool setup! The reason i said a safc which wouldnt be needed is to push more fuel to air for the valves and the cam unless i am wrong then please chime in. thanks
 

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If you do something to the engine to make it suck more air in, the AFM will read it and add more, as far as I know. If you are really power hungry get a wideband and see what your motor is doing before blindly dumping in more fuel.
 

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Donn29 posted
"If you do something to the engine to make it suck more air in, the AFM will read it and add more"

Not quite true. We're talking about wot. The AFM is designed to fully open at 6500 rpm at wot on a stock NA engine. As more airflo capability is added the AFM will fully open at wot at lower rpm. The ecu will probably partially compensate adding some additional fuel since the ecu thinks that the AFM is out of calibration because the AFM opens fully at lower rpm. Tightening the AFM spring and going up to 210 injectors should let the ecu operate closer to normal A/F ratios.
 

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Donn29 posted
"If you do something to the engine to make it suck more air in, the AFM will read it and add more"

Not quite true. We're talking about wot. The AFM is designed to fully open at 6500 rpm at wot on a stock NA engine. As more airflo capability is added the AFM will fully open at wot at lower rpm. The ecu will probably partially compensate adding some additional fuel since the ecu thinks that the AFM is out of calibration because the AFM opens fully at lower rpm. Tightening the AFM spring and going up to 210 injectors should let the ecu operate closer to normal A/F ratios.
I really shouldn't comment as I haven't really too much AFM knowledge outside of toying with my 5M-GTE. I hope to data-log it once I get the car up and running again to learn a bit more about when it maxes out(which was TPS based I thought, unless the AFM is maxed out, or perhaps the ECU can't tell its maxed out but that wouldn't happen unless you are at wot?).

However, adjusting the spring tension is probably a better idea than a SAFC, however it is still a bit crude unless you are using a WB or something. My thoughts are this. If the engine is bringing in a touch more air, and the ecu is set to be rich at wot, you'd be getting closer to stoich, thus making more power than adding more fuel may yield. Of course, I'm only talking out of my ass, LOL. Most of my theories are based on Reading between the lines of the TSRM and deciphering what I've read from the forum.
 

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But with too much air and too little fuel wont this lead to detonation even though it is not turbo'd?
The only reason I said safc is because you can control how much air and fuel the engine recieves!
 

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But with too much air and too little fuel wont this lead to detonation even though it is not turbo'd?
The only reason I said safc is because you can control how much air and fuel the engine recieves!
I'd be surprised. But Either way I'd use a wideband to determine the amount of lean-ness before adding or making adjustments on a SAFC.
 

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good point!!!!!!
Im gonna build me up a full out head for my 7m like I explained.
but I'd assume it would be safer to run it on the rich side even with the loss of hp.
 

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You'll never know without a wideband if you are just wasting fuel or making the most of those cams and other parts.
 

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Well I remember seeing/reading that you just cannot throw cams in! Sopposely
you will feel a difference but you will never achieve all off the power the cams have to offer without further mods. please correct me if im wrong and this also goes for the valves. But i do agree on the wideband. At least you can see what your engine is doing then.
 

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...but you will never achieve all off the power the cams have to offer without further mods....
I would agree, but by themselves they probably won't hurt anything.
 

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I mean with just valves by themself you would fill a kick in the engine. But I dont see more then a 4 to 8 hp gain I could be wrong on my num just a gestimation.
 
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