i have a 87 SE maxima and was curious what i could do to get more power. I dont want to swap the motor or add a turbo or superchargers, i would just like to know some mods i could do to increase my power. thanx alot

 

Well lets see. You can build a CAI, build a custom 2.5" exhuast with high flow cat, or by a pacesetter catback system. There is the 240SX/U12 Stanza Throttle Body Swap, 87-88 300ZX ECU swap, port and polish your heads, get one of the high flow intake manifolds, upgrade your ignition system, Advance the timing to 24*BTDC (is that right?) and run 91+ octane fuel, and the last thing I can think of, though it can be very risky if done wrong...run N2O. Oh yeah, you can also probably swap some z31 headers in that match too, if they'll fit.

S

 

with the intake, exhaust, and advanced timing and the throttle body, with an auto, you should be able to hit 16 flat pretty easy, maybe better.

anyway, how the hell are those headers supposed to fit?? its friggen transverse engine fwd lol.

 

16's? damn my car can run mid to high 15's....I would think that stuff might put us into the mid to low 15's with the 5-speed. Then again...you did say auto. :P

S

 

That's why he said "If they'll fit". The headers for the Z31 may fit, but it's never been tried as far as we know. I've been trying to find a picture of a pair, to see if they will, but I haven't found any. It's possible, if they are routed correctly, but you would definately want to provide some form of heat shielding, to protect the hoses and wires running along the firewall, as well as those by the radiator.

 

Headers from the z31 should fit, its the same engine. Maybe the internals would be different because it would be alittle more performance based but its all the same on the outside. Hmm Local junk yard hunt will happen this weekend to check that out.

 

Hmm...guess I gonna have to find some z31 headers and do it on my car....gotta get money for that though...

S

 

Fitting to the engine will be a given, but will the headers be routed correctly to fit the Maxima chassis? That's the big question. Now, the ideal would be a set of headers, with like 1" primaries from the heads, with unequal, tri-y design leads that follow the path of the original manifold and crossover pipe, as this would allow the O2 sensor to still function properly, without having to re-wire and move it. They should merge into a 3" collector, which would then be necked down into a 2.5" inch head pipe, feeding a high-flow cat, to a straight pipe (ie. no resonator), and capped at the end with a single Dynomax or FlowMaster muffler. If you want the dual tips on an 87-88, then have the muffler mounted a little closer to the front, and use a "Y' type exhaust tip. If not, you could use one of the 3" resonator tips that has the baffles built in to help "tune" the sound.
Before these headers, or any headers, could ever be installed in our cars, they would have to have heat wrap wrapped around them, to reduce the heat generation, or we'd be burning our P/S pressure hose, P/S rack, and several smaller heater hoses and wires all the time...

 

Another option could be "Shorty" style headers, with a y-pipe type configuration, like in the 3rd gens...but that will require moving the o2 sensor downstream, so it can get a reading from both banks of cylinders.

 

I don't think the Z31 headers will fit. I read somewhere that the reason why the N/A Z31 puts out a few more horsepower than the 2nd gen Max is because they had to change the header design and make it more restrictive in order to fit inside the 2nd gen engine compartment.

-C-

 

You're right. That's what it said at http://secondgenmax.sifen7.com/artic...nd_mar_85.html "The same engine in the 300ZX makes 160 hp, the difference being in the intake and exhaust plumbing changes necessitated by the transverse arrangement." It seems that if Nissan could've put the headers on they would have.

 

yeah after I had posted that I remembered nismo87 telling me something about something not meeting up. So it wouldnt fit. So disregard my prev. post.

 

If only we had a way to have some custom fabricated for cheap...

 

Actually what you need is someone with a welder and some patience. I know the Z headers will bolt onto the heads on the maxima. However the front header would hit the tranny and the rear would hit the tranny as well. What I would do is buy a cheap pacesetter header for a Z31 and measure it. Next you have to figure out how your going to connect the rear bank to the front. To do this you have to run it simular to how it is from the factory. Otherwise you'll hit the oil filter (unless you relocate it and that isn't cheap)!

I can make a simple drawing describing my idea if it would help anyone out. Front would be the easiest though. Then you have to figure out how big/long to make the secondaries (downtube). I figure go with a design simular in dimension to the WSP Y pipe for VGs in 3rd gens. Then run a 2.5in collector to a 2.5in cat and you are all set. For this project expect to spend $200-800 if you can't DIY. If you knew some friends in a welding school this would be a good time to get their help for a "school project" .

 

Being a bit of a car n00b, would it be wise to start with just the throttle body and ECU swap? Those seem to be the simplest and cheapest modifications, but can they be done alone and still provide a noticable improvement in performance?

 

Definately....but remember if you do the throttle body mod, you have to...let me repeat this...you HAVE to bore out the inlet on the intake collector to 60mm to match the TB, or else it completely defeats the purpose of having it. Those will give you better throttle response and probably a few ponies if you add a cone filter. To get even more power...you want to run a CAI right off the throttle body....with room for the MAF sensor as well a ways to connect all the vacuum lines and PCV hose.

S

 

yup.. but seriously, upgrading the tb wont be as effective if everything upstream of it is still stock. not saying you wont notice a difference, you probly will, but i personally would start at the beginning of the air path and work towards the engine from there, as opposed to working from the engine out

 

I did the upgrade and the performance increase was very noticeable. Outside of the exhaust and intake it was the most noticeable mod. It improved my gas mileage and throttle response.

 

That is what I am trying to do. I know I will have to buy another intake mainfold after I hone the intake manifold to 60mm. In case I decide to sell my car.

 

Yeah, that is one of the things I will be doing fairly shortly too.

S

 

Would you really have to buy another intake? Couldn't we just put the old TB back on? Would anybody know the difference from the outside? I don't think that it would be dishonest to not say it had been done as it shouldn't affect performance or effeciency if the 50mm TB were in place. On the other side, if you properly explained to the potential buyer the modification and the fact that the 50mm TB negates the effect of the mod, would they care that it had been done?

Also, is the 300ZX intake plenum better than the Max's? If so, is it already 60mm or would the same modification have to be done (ie: TB swap, intake bore increase)? I have found a source for a 60mm TB, 300ZX intake and ECU, but the parts listing shows an upper and lower intake manifold. Do I need both to use the 300ZX intake manifold or do I just need the upper? The lower is listed "with injectors", so I'm thinking that it's the intermediate piece that goes between the plenum and the head. Is it necessary to use the 300ZX injector section? Is it any better than the Max's?

 

Well, here's the deal, 300zx intake plenum is a different design, there would be a lot of modification you would have to do. Plus you will run into clearance issues with the hood. Not to worry, the 300zx intake plenum is also 50mm. Both our intake manifolds are similar. There is an upper piece and lower piece. I believe the lower piece is the same for both, just a different upper intake. If you gonna do anything, you want get the 89-91 Stanza or 240sx. Also look at getting an 88 NA 300zx ECU if your going for the different ECU.

S

 

Thanks for clearing that up. It'll save me some money and worry knowing that the 300ZX intake is basically the same. The ECU I found is for a 5 speed NA 300, and my car is also a 5 speed, so I think I found the right one. Does it matter what year of 300? I think I found an 85, 86 and an 87, if memory serves.

Leigh

 

I am getting the exact year ECU. There may have been small changes in the ECU from 85 thru 87 even though the engine stayed the same.

And oh, SpecV, I am getting the other throttle body in case I screw up the other one. Can't afford to have a car down because of a modification your car won't accept. So if the TB mod causes my car to act funny, or lose gas milage, just put the original back on.