You are assuming that the intake tube is restricting the engine from making any more power, which isn't true.

The spacer doesn't have to significantly increase volume to increase flow. If all the spacer did was reduce temps, then there wouldn't need to be different sized spacers, with different results.

I have installed the spacer and MREV2, but according to your previous posts, the MREV2 can't possibly do anything (without changing intake tube diameter) because it is behind the MAF.

 

bump for so good info.

 

I'm not knowledgeable on the advantages of the MREV2 over the stock intake mani. I have the DE motor. I was under the impression the MREV was good because of the smoother internals allowing for less turbulence. Maybe you could school me on it. Look, I copied right from the Motordyne site. They didn't indicate from their description of their product anything that leads me to believe what you stated. Sure there is more air in the intake. That makes sense since it is thicker internally. But it still shouldn't run leaner simply because there is more air inside the intake plenum for the motor to take in. That makes ZERO sense. All of the air inside the intake was still metered through the MAF so the computer can adjust fuel and air trims to make the proper mixture. Accept that your comment there is not exactly factual. I'm not saying you're wrong, just not thinking that through.

Also what makes you think the intake tube isn't restricting the motor? A certain diameter tube can only flow so much air period. Otherwise what's the point of increasing the diameter? You ever tried drinking through a straw (rhetorical question, I'm sure)? If you suck hard enough (this could really be taken out of context) eventually the straw could collapse because the pressure pulling the fluid or air through the straw is stronger than the straw is overall. Now obviously intake tubes are quite strong and the fear of collapse under suction isn't a worry in the least bit, but there comes a point, even with the smoothest internal walls, that turbulence takes over and limits how much air moves through the tube. Eventually you have to increase the diameter to feed the motor enough air. Purse your lips and suck in then open your mouth and suck in. You're still moving the same amount of air since your lungs are a preset size. But the difference between the two procedures allows for less effort required to move the same amount of air. That alone can free up power with less engine load.

Believe me, I'm learning something here too. So don't get all defensive on me. I'm not attacking your intelligence. I have more tact than that. Teach me something about the MREV2 intake. I know little to nothing of it. But also read through what I post and see where I'm coming from. I have no formal education in this subject, but I am an educated man. I've built old-skool cars as well as modern, electronic tuned cars.

 

I'm sure you realize that the 1st gen spacers that Motordyne developed and still sell are marketed simply as a spacer with no mention of thermal isolation? And that subsequent versions are still "spacers" despite the addition of thermal isolating gaskets and coolant control valves?

I'm no physics expert but can see that they claim to add 11-13 HP with the basic spacer and 12-14 HP with the isothermal version. That suggests that the biggest benefit comes from improved air flow rather than attempts to reduce heat soak.

http://www.motordyneengineering.com/index.php?cPath=1_5

 

What's your point? Because they don't mention any cooling benefits means that it doesn't. Please! You realize that there is nothing in the Iso-thermal kit that's different other than an addition of a few gaskets and a coolant control valve for the throttle body? I can see how those couple pieces suddenly offer it improved cooling characteristics (sarcasm inserted here). Either "spacer" is inserted between the upper and lower plenum.

 

i see and hear alot of people getting BC coilovers but also see complaints etc of creaks and stuff so im looking into coilovers, i have heard a good brand if dont mind spending a bit more than BC's is Apexi Coilovers.

anyone got them? had them? got remark about them? i dont mind paying the little extra cost over BC if it means me getting a better quality and less issues.

thx

 

I was going to stay out of this - but it keeps going around in circles...

His point is; the plenum spacer's performance characteristics is not from lowering temps (as you stated earlier) - it is from volume... it is the same principal that the Crawford plenum used (prior to spacers), which is actually what prompted Tony to design a spacer as a cheaper alternative (this was before he developed Motordyne, the prototype was for his personal use).

The original Kintetix plenum had the same concept (taller for volume) but also had slight thermal benefits from being made from composite rather than aluminum.

 

Then why does the MD site state the thermal cooling benefits for the Iso and the Iso Copper? I'm not making this stuff up. True, the regular one doesn't. But the step-up kits do. Again, where does adding volume to the intake plenum help make power when the motor (piston down, piston up) has a preset amount of air capacity? I'm not arguing simply for the sake of arguing. Generally I don't get involved in any thread unless I have something to input. But all this is just bad math unless someone can show me something scientific that supports how the increase in volume in the intake (before any work is performed) helps make more power. I'm open for anything so long as it has something tangible to understand.

 

The "Iso-Thermalmal Kit" is not the spacer itself - it is a combination of ancillary pieces (lower manifold gasket, and coolant control valve either the manual valve shutting off the coolant flow to TB or the copper unit that automatically stops flow based on temps), the plenum spacer is exactly the same whether you buy it alone or with the Iso Thermal kit.

The concept of the spacer is relatively common knowledge these days... there have been many interation of the concept (Crawford plenum, Kintetix plenum, APS tall boy, a various spacers) - the slope of the upper plenum restricts airflow to the front intake runners - adding a spacer (or taller plenum) allows for more air to flow to the front runners (so yes, it is about volume)... All of this has been discussed at length in many other threads (probably old threads by now, because like I said it's common knowledge these days).

I'm not interested in going in circles here with you... in fact, this is the kind of stuff that has made many of us less interested in this forum anymore... but you really should be better versed on the topic before you post such advise.

 

Point taken. As I said - I'm not being a smart a$$ here. Since you spoke of it the way you did it makes sense if it's to correct a flow issue with certain cylinders. Maybe it is common knowledge. In my defense, I've owned this car for a shade over 1 year and a member here less than a year. With umpteen thousand threads to go through and decipher worthless banter from valuable information is next to impossible on here. From all the various designs of cars and trucks I've modded, this particular quirk didn't exist. With nearly every such application, the spacer was intended for cooler air, not volumetric increases. Many of the spacers I've dealt with were phenolic blocks to isolate particular intake parts from the heated generated from the motor. So don't add me to the list of people that make this place less interesting. Someone asked a question - I answered based on the knowledge and experience I have. If people can't maintain an argument as simply a difference in knowledge levels or opinions and has to get hurt over it, fine. I'm not like that. I can argue as well as admit when I'm not totally informed. Your explanation was what I was looking for - someone to break down why in this application the spacer benefits more than just cooler air.

For what it's worth - I still can't see how adding this spacer will lean out the fuel trim. All 6 cylinders are pulling from the same storage of air. If 2 cylinders were restricted as you stated, you would think it would run fat on those 2 cylinders with stock intake manifold and then lean out to a normal fuel/air mix with the spacer added. All the air still comes through one meter. Do I need to go through really old threads before asking this question to see if my rookie eyes missed something else that's now common knowledge?

 

I dont want to search through old threads either... so here are a few links instead (you can argue with them about the merits of a plenum spacer)

http://www.z1motorsports.com/350_g35...oducts_id=2854

http://www.stillen.com/product.asp?i...SAN&model=350Z
(note this one is composite, which is why they add that is lowers intake temps - in addition to what you seem not to accept (volume).

I could go for days with different sources... but instead I'll just leave you with this last one - since you like referencing Motordyne:

http://www.motordyneengineering.com/...pID=8&CDpath=0

can we end this now.

 

Hey man i got a 05 g35 sedan as well just black w/ factory spoiler and im a teen as well, only 18 ha ur reply was way helpful just how much hp u gain from all ur engine and exhaust mods and how much did it all cost???

 

Hey guys I got an 05 G35 6MT sport sedan. wondering is it worth getting the coupe mid pipe and y pipe? would I see any real gains? sound difference?

 

i think the coupe mid pipe is almost the same as the 05-06 sedan mid pipe. the y-pipe is exactly the same, you could get an HR y-pipe

 

Coupe middy was a few pounds less due to the smaller resonator on it compared to the sedan pipe. I too was informed the Y-pipes are the same.