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Hey all!

Is there any way to increase the HP in the DOHC without replacing the whole engine?
My budghet dont quite cover an enginge change right now but i would still like to get a little extra out from my car

Theres not much you can really do to the DOHC motor. No headers are available unless you want to go custom. A cold air intake and exhaust are probably the only mods you can do to increase the power of your stock motor but these gains will be minimal. Not many performance add ons for this motor that is why many people swap them out. Hope that helps my friend!!

Originally posted by Redlined:
Theres not much you can really do to the DOHC motor. No headers are available unless you want to go custom. A cold air intake and exhaust are probably the only mods you can do to increase the power of your stock motor but these gains will be minimal. Not many performance add ons for this motor that is why many people swap them out. Hope that helps my friend!!

Not to disagree, there is quite a bit you can do but you have to do reserach ahead of time and think a bit outside of the box.

What type of budget are you looking at and how much power are you trying ot gain?

im tryin to gain a good 200 HP on my 100$ budget... wanna help me lol

I'm not aiming at anything specific since i know you cant get very high without spending much money, if it was as cheap here as it is in the states i would have already changed my engine but now i dont have that luxury so i'll have to do with whatever enhancements i can!

For example i already fixed my DOHC engine for about the same price as i see you guys getting your BPT and ZE swaps and whatever done and i got away cheap. This was just a replacement dohc and installment.

weight reduction-- free
port/polish heads $~600
different cams
msd ignition/spark plug wires/plugs
rx7 vaf

weight reduction will make you feel like you gained a lot of horsepower for almost nothing. weight reduction makes a nice difference in mileage, handling, and acceleration.

port/polishing can also be free if you have the right tools. there are plenty of how-to's online for port/polishing almost everything from header to head internals to intake manifold to throttlebody. as long as you know how to take apart the engine and reassemble it, it can be free.

for now i'd go with your basic bolt-ons first. exhaust, intake, maybe some new injectors, rx7 maf and fuel pump.

oh forgot you can advance/retard the timing too.

Have you guys forgotten about NOS? Lorco had a special on not too long ago for a universal 4 cyl ZEX kit. up to a 75 hp gain, and if you are planning on eventually doing a motor swap, then not to be worried about wrecking the stock engine. I know someone with a stock probe(not a gt)and juiced it with a 150 hp kit, and he never ever had any engine problems. maybe this could be an add on for you. If nothing else when you show off the system, it will make some of us drool!!=)

well intake
exhaust

the dohc doesnt need the rx7 maf b/c its not the trap door style

remeber the DOHC i4 has 105 HP

u can source alot of stuff

i personally dont like NOS b/c it seems the easy way to HP

Originally posted by monty73741:
i personally dont like NOS b/c it seems the easy way to HP

and you prefer the hard way??

Originally posted by marshmallow15:
oh forgot you can advance/retard the timing too.

Remember that if you advance the timing, you'll have to run w/premium grade fuel to avoid "engine knock" which will damage your motor. Definitely worth it IMO where I live because gas is cheap in the states compared to Europe, but still a cost factor you might want to consider. btw, I found this to be a nice little 1.6L DOHC seat-of-the-pants performance enhancement costing nothing but the higher grade fuel. Helps maintain respectability around all the pimped-out Civics around here too...

Actually, According to Chiltons, The I4DOHC is 105, If you have an automatic, It is 116HP in a 5speed Model.

Nope, I4 DOHC is 105 in both models. Same ECU, Same motor, everything. Only difference is the ATs have an ATCM.

as to the easy way of HP
i dont like Nitrous b/c the hook up is way too easy for me
i rather do a custom turbo etc....its more techincal & its more work...i enjoy the workin on the car as apposed to just havin a kit