Crawford Plenum - Ill be the first to say something.
11-01-2003, 03:01 PM
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Crawford Plenum - Ill be the first to say something.
So we here in cali went to dyno our cars at a shop today.
Suprizingly the man running the dyno was very intelegent and really know what he was talking about.
We were all anxious to see a car with a Crawford plenum. And WOO WOO! We saw one had one once it went on the dyno! So we all got excited to have a looksie...
If I remember correctly, it had a Pop Charger / Crawford Plenum / High Flow Cats from Lemar? / Borla TD...
It dyno'd with not a very impressive horse power rating but with higher TQ numbers.
After this we were talking with the man about the plenum and how it was designed.
He explained how a Flow Bench test's with a high constant flow of air with a vacum to test the flow of the plenum. But he then explained that engines dont work that way, its a burst of air then none then a burst then some. Something a flowbench cant duplicate. Plus the engine doesnt suck in as much air as a flowbench would measure.
Now. If you take the stock plenum and put it on a flow bench and force tons of air threw it of course you are going to see a difference in what is getting to some cylanders...
Its like with the Track model and its Underbody Diffusers... They change the drag what like 0.02%... you wont notice any difference on the road but at 200 MPH that will make a difference...
So what I see from all of this...
In a Normally Aspired engine set up the Plenum is not a good use of your time / money.
BUT how ever having a better understanding of how flowbenches work the Plenum will Improve air flow for a Forced Induction application.
From our dyno day. Best gains were shown from believe it or not. Underdrive Pullies...
There will be a threat posting all of our numbers and mods soon.
let the
begin 
Suprizingly the man running the dyno was very intelegent and really know what he was talking about.
We were all anxious to see a car with a Crawford plenum. And WOO WOO! We saw one had one once it went on the dyno! So we all got excited to have a looksie...
If I remember correctly, it had a Pop Charger / Crawford Plenum / High Flow Cats from Lemar? / Borla TD...
It dyno'd with not a very impressive horse power rating but with higher TQ numbers.
After this we were talking with the man about the plenum and how it was designed.
He explained how a Flow Bench test's with a high constant flow of air with a vacum to test the flow of the plenum. But he then explained that engines dont work that way, its a burst of air then none then a burst then some. Something a flowbench cant duplicate. Plus the engine doesnt suck in as much air as a flowbench would measure.
Now. If you take the stock plenum and put it on a flow bench and force tons of air threw it of course you are going to see a difference in what is getting to some cylanders...
Its like with the Track model and its Underbody Diffusers... They change the drag what like 0.02%... you wont notice any difference on the road but at 200 MPH that will make a difference...
So what I see from all of this...
In a Normally Aspired engine set up the Plenum is not a good use of your time / money.
BUT how ever having a better understanding of how flowbenches work the Plenum will Improve air flow for a Forced Induction application.
From our dyno day. Best gains were shown from believe it or not. Underdrive Pullies...
There will be a threat posting all of our numbers and mods soon.
let the
begin
11-01-2003, 03:59 PM
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my car is stock except for the plenum and I noticed a big difference in the upper rpm's. many like me have said the same. it is true that the plenum will probably help an fi setup more, but it's still a nice bump in power for an NA z.
Last edited by zeroday; 11-01-2003 at 04:02 PM.
11-01-2003, 04:37 PM
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Re: Crawford Plenum - Ill be the first to say something.
Originally posted by KONVERTER
But he then explained that engines dont work that way, its a burst of air then none then a burst then some.
But he then explained that engines dont work that way, its a burst of air then none then a burst then some.
11-01-2003, 05:51 PM
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An NA motor sees a constant influx of air....the performance itself is absed on how efficently the motor inhales. The more you can smooth out the runners and improve inconsistencies, the better the motor can inhale, and the better the overall power will be. With FI, you are forcing air through it, hence you can have a much poorer intake design, and it still will work very very well.
11-01-2003, 06:11 PM
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All numbers posted on this issue So Cal section
350Z4steve can you post your dyno sheet so we can see the high end vs the low end #s only plenum run today w/ popcharger
350Z4steve can you post your dyno sheet so we can see the high end vs the low end #s only plenum run today w/ popcharger
11-02-2003, 12:47 AM
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Re: Crawford Plenum - Ill be the first to say something.
Originally posted by KONVERTER
So we here in cali went to dyno our cars at a shop today.
Suprizingly the man running the dyno was very intelegent and really know what he was talking about.
We were all anxious to see a car with a Crawford plenum. And WOO WOO! We saw one had one once it went on the dyno! So we all got excited to have a looksie...
If I remember correctly, it had a Pop Charger / Crawford Plenum / High Flow Cats from Lemar? / Borla TD...
It dyno'd with not a very impressive horse power rating but with higher TQ numbers.
After this we were talking with the man about the plenum and how it was designed.
He explained how a Flow Bench test's with a high constant flow of air with a vacum to test the flow of the plenum. But he then explained that engines dont work that way, its a burst of air then none then a burst then some. Something a flowbench cant duplicate. Plus the engine doesnt suck in as much air as a flowbench would measure.
Now. If you take the stock plenum and put it on a flow bench and force tons of air threw it of course you are going to see a difference in what is getting to some cylanders...
Its like with the Track model and its Underbody Diffusers... They change the drag what like 0.02%... you wont notice any difference on the road but at 200 MPH that will make a difference...
So what I see from all of this...
In a Normally Aspired engine set up the Plenum is not a good use of your time / money.
BUT how ever having a better understanding of how flowbenches work the Plenum will Improve air flow for a Forced Induction application.
From our dyno day. Best gains were shown from believe it or not. Underdrive Pullies...
There will be a threat posting all of our numbers and mods soon.
let the begin
So we here in cali went to dyno our cars at a shop today.
Suprizingly the man running the dyno was very intelegent and really know what he was talking about.
We were all anxious to see a car with a Crawford plenum. And WOO WOO! We saw one had one once it went on the dyno! So we all got excited to have a looksie...
If I remember correctly, it had a Pop Charger / Crawford Plenum / High Flow Cats from Lemar? / Borla TD...
It dyno'd with not a very impressive horse power rating but with higher TQ numbers.
After this we were talking with the man about the plenum and how it was designed.
He explained how a Flow Bench test's with a high constant flow of air with a vacum to test the flow of the plenum. But he then explained that engines dont work that way, its a burst of air then none then a burst then some. Something a flowbench cant duplicate. Plus the engine doesnt suck in as much air as a flowbench would measure.
Now. If you take the stock plenum and put it on a flow bench and force tons of air threw it of course you are going to see a difference in what is getting to some cylanders...
Its like with the Track model and its Underbody Diffusers... They change the drag what like 0.02%... you wont notice any difference on the road but at 200 MPH that will make a difference...
So what I see from all of this...
In a Normally Aspired engine set up the Plenum is not a good use of your time / money.
BUT how ever having a better understanding of how flowbenches work the Plenum will Improve air flow for a Forced Induction application.
From our dyno day. Best gains were shown from believe it or not. Underdrive Pullies...
There will be a threat posting all of our numbers and mods soon.
let the
begin
You are the first person to say a bad thing about crawfords plenum (besides wahhhhh! I cant keep my stock stress bar
) Either its a good mod or all these peeps are trying to avoid buyers remorse by lying to themselves. I am inclined to believe that the plenum is a good mod. Now if indeed you are basing his power appraisal on a basline then I would have to say that he should lose the JWT pop charger. Look at the facts; all the crawford crew are running stock intakes. They say our airbox is pressurised. I also recall hearing that the pop charger lost HP on several occaisions. Gains or not perhaps the plenum works best with our stock airbox.
My opinions are based on what I read on this forum of course ,but as someone who is relatively saavy about cars i will say this... Crawford plenum might end up on my car but there is NFW I will be fiddling with my intake system. I think they are all worthless, and of them all I gather that the JWT pop charger is the most worthless of all!
Remember Im not flaming! Thats just my opinion if anyone gives a rats patootie!
Peace
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11-02-2003, 01:25 AM
#8
....for your health
Reading the results posted in the SoCal forum it looks like only one guy had the plenum and he came in third with 257 rwhp. Only 9 rwhp behind Jeff's and 1 rwhp behind zxsaint's. Looks like the plenum is good for some power to me.
My understanding is that the main advantage of the Crawford plenum is that it opens up and get more air to the forward most cylinders which are staved for air by the stock plenum. The engine is sucking in air and the more efficiently it can do this the more power it can produce.
Crawford did a GREAT deal of R&D and I would trust that Doug and the guys at Crawford know what they're talking about. I would be willing to bet that they have spent more time at the flow bench than the guy you spoke with will spend in his entire life.
Just my
My understanding is that the main advantage of the Crawford plenum is that it opens up and get more air to the forward most cylinders which are staved for air by the stock plenum. The engine is sucking in air and the more efficiently it can do this the more power it can produce.
Crawford did a GREAT deal of R&D and I would trust that Doug and the guys at Crawford know what they're talking about. I would be willing to bet that they have spent more time at the flow bench than the guy you spoke with will spend in his entire life.
Just my
Last edited by failsafe; 11-02-2003 at 01:42 AM.
11-02-2003, 04:23 AM
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Well we all know it had to happen, there had to be one, and after all this time - Here He Is. And he doesn't even have a Crawford, never even drove a car with one, just observed a "test" with the Crawford and some other stuff of dubious value.
I've said these things before, but one more time wont hurt.
First, the Zs intake is just about perfect, the large opening sits smack dap in a high pressure area at the front of the car and draws in cold air. The only way to improve it, is to drop a K&N into it.
Second, of all the mods today, the Crawford is the best bang for the buck out there. I know, I have one. I haven't done that much to my G. Put a Z tube intake on it, the K&N, ground wires, and a dual exhaust system. The plenum made itself known the first time I ran it through the gears above 3500 RPM. It flat out works, and anybody who says otherwise has his head up his butt. Sorry, but that's the way it is.
Oh yesterday, I changed my oil - put a chrome oil cap on it. Looks great and adds at least 15 HP.
Lou
I've said these things before, but one more time wont hurt.
First, the Zs intake is just about perfect, the large opening sits smack dap in a high pressure area at the front of the car and draws in cold air. The only way to improve it, is to drop a K&N into it.
Second, of all the mods today, the Crawford is the best bang for the buck out there. I know, I have one. I haven't done that much to my G. Put a Z tube intake on it, the K&N, ground wires, and a dual exhaust system. The plenum made itself known the first time I ran it through the gears above 3500 RPM. It flat out works, and anybody who says otherwise has his head up his butt. Sorry, but that's the way it is.
Oh yesterday, I changed my oil - put a chrome oil cap on it. Looks great and adds at least 15 HP.
Lou
Last edited by lowrider; 11-02-2003 at 04:26 AM.
11-02-2003, 06:10 AM
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Power is power. What Konverter was saying that a tured air delivery of the Crawford Plenum would have more value in a pressurized forced induction then a low pressure N/a delivery. Bench work and street work are two different things. The guys at Power Train Dynamics have been testing new things for magazines for over ten yours now. Some make hp and some talk about hp.
I think all of the guys except Jeff , This was there very first dyno. Ya it would have been better to have stock baseline data for all the cars, but we can't roll back time.
Zxsaint, I think has one of those very few exceptional cars. Luck of the draw and Richard 350z may very well have its twin but well have to see.
Except the numbers for what they are,
just numbers. Appreciate them, 10 guys paid $75 ea to get them for you.
I think all of the guys except Jeff , This was there very first dyno. Ya it would have been better to have stock baseline data for all the cars, but we can't roll back time.
Zxsaint, I think has one of those very few exceptional cars. Luck of the draw and Richard 350z may very well have its twin but well have to see.
Except the numbers for what they are,
just numbers. Appreciate them, 10 guys paid $75 ea to get them for you.
11-02-2003, 06:19 AM
#11
Originally posted by failsafe
Reading the results posted in the SoCal forum it looks like only one guy had the plenum and he came in third with 257 rwhp. Only 9 rwhp behind Jeff's and 1 rwhp behind zxsaint's. Looks like the plenum is good for some power to me.
Reading the results posted in the SoCal forum it looks like only one guy had the plenum and he came in third with 257 rwhp. Only 9 rwhp behind Jeff's and 1 rwhp behind zxsaint's. Looks like the plenum is good for some power to me.
He had Borla headers and a LBMS highflow cat, Borla exhaust, JWT popcharger and the plenum. The two mods in bold were omitted in Mr. T's first post. Steve has a lot of mods aside from the plenum and it's no surprise he came in third. Actually, I was expecting he would do much better than my runs considering he had headers and the plenum.
Consider my set-up. No headers, no plenum, the LBMS testpipes with resonator, the same Borla exhaust and the same JWT popcharger. Yet I posted numbers that were 1 hp less but a couple points more of torque.
This suggests to me either the plenum and Borla headers don't produce much or the LBMS testpipes with resonator produce more.
I don't know what the answer is about the Crawford plenum. I do know the dyno man knew his stuff. And, he was sceptical about the plenum. He did comment that with FI and more horses, the plenum might make more horses. But, from the dyno, there was nothing in the air/fuel ratio to suggest it was doing anything.
We need to consider people like RodH saying he feels the power gain. These kinds of subjective comments carry weight. And, more dynos will provide objective evidence of gains or non-gains.
11-02-2003, 07:17 AM
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Fact is you dont need to listen to me 
The dyno shop guy is making his educated guess... and I am making mine in agreeing with him...
Correct I never drove a car with a crawford plenum on it...
I have drivin other cars with upper intake manifolds bored out and polished and noticed improvements to the upper RPM range performance...
It still just strikes me odd that Nissan a company that spends millions in engine development wouldnt catch something like what the Plenum claims to improve...
Im not saying it doesnt improve anything...
Im not saying the plenum is a waiste of mone...
The plenum was designed on a flowbench which to my understanding does not work the way the Plenum recieves air on the engine.
I think they Greatly improved the plenum for use with Forced Induction. But for NA its an OK mod.
The dyno shop guy is making his educated guess... and I am making mine in agreeing with him...
Correct I never drove a car with a crawford plenum on it...
I have drivin other cars with upper intake manifolds bored out and polished and noticed improvements to the upper RPM range performance...
It still just strikes me odd that Nissan a company that spends millions in engine development wouldnt catch something like what the Plenum claims to improve...
Im not saying it doesnt improve anything...
Im not saying the plenum is a waiste of mone...
The plenum was designed on a flowbench which to my understanding does not work the way the Plenum recieves air on the engine.
I think they Greatly improved the plenum for use with Forced Induction. But for NA its an OK mod.
11-02-2003, 07:28 AM
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Richard where's Richard 350Z he can settle this. Reportedly 301hp before Crawford . Well he should be at about 320 now. lets hope when he gets well and dynos on" our dyno" he doesn't loose 70 HP???????
11-02-2003, 07:51 AM
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The Numbers themselves do mean something as in who's car is more powerful, but it's kind of pointless unless you have the baseline dynos. I don't care who has the most power cuz some Z's come out the box with 5 to 10 more wheel hp than the other, and nearly every single one will vary. I'm more interested in who gained the most hp from stock with their mods.
11-02-2003, 08:08 AM
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Enough now we now have 10 base lines to base future mods on. Lets get the guys together again in say 60 days and retest with all new stuff added. Who game?
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11-02-2003, 08:17 AM
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It was interesting to see all the z's out with the various mods getting dyno'd. Im not surprised by the results at least in my case with the plenum, reason I say that is because in my best educated guess prior to getting dyno'd and having only driven the car literally around the block a few times after install before yesterday it really didnt feel like it added anything but then again it didnt feel like it hurt anything either that Or my ECU has not adjusted completely because right after install I got a CEL. Im guessing forgetting the rubber plug didnt help so it had a air leak. Well anyway I reset the ECU and havent had the CEL go off since but then again I would say I havent driven more the 25 miles with the plenum install since reset. My point is prior to this each and every mod has felt like its been contributing to something in the power and the crawford was my last ( also to serve as a test to see whether investing any thing else
NA wise is worth it) That remains to be seen even those with CAMS Jeff and B18vudoo (both similar mods) yesterday did not put out numbers I would expect quite low in B18's case also my proof is a week prior to this I drove B18's he drove mine (this before my plenum)
He is all nismo -->(intake/headers/exhaust/CAMs/flywheel) all I had was Pop intake/headers/exhaust (borlas)/ free flow Cats)
Ask B18vudoo what he felt impressions between his and mine and I think he called it they felt mostly the same top end wise and not much diff power wise.So going back to this how long does it take for a ECU to adjust and optimise for gains and given a cars history when you reset the ecu does it negate anything even settings of a well broken-in car? What does suprise me with my gains is the Air fuel ratio ( I was expecting that to be all over the map given the above scenario and seeing how everyone there at the dyno was way crazy and not linear with few exceptions the guy with the flashed ECU (from techno) mine turned out decently <---- which I find odd and surprising so in that sense not counting pure numbers at least my car doesnt ping or knock and its very linear and smooth with the power it does have. Im off to SEMA and the next route is FI for me better payoff in the end when I decide to do it. My numbers look interesting enough like this setup
crawford setup
NA wise is worth it) That remains to be seen even those with CAMS Jeff and B18vudoo (both similar mods) yesterday did not put out numbers I would expect quite low in B18's case also my proof is a week prior to this I drove B18's he drove mine (this before my plenum)
He is all nismo -->(intake/headers/exhaust/CAMs/flywheel) all I had was Pop intake/headers/exhaust (borlas)/ free flow Cats)
Ask B18vudoo what he felt impressions between his and mine and I think he called it they felt mostly the same top end wise and not much diff power wise.So going back to this how long does it take for a ECU to adjust and optimise for gains and given a cars history when you reset the ecu does it negate anything even settings of a well broken-in car? What does suprise me with my gains is the Air fuel ratio ( I was expecting that to be all over the map given the above scenario and seeing how everyone there at the dyno was way crazy and not linear with few exceptions the guy with the flashed ECU (from techno) mine turned out decently <---- which I find odd and surprising so in that sense not counting pure numbers at least my car doesnt ping or knock and its very linear and smooth with the power it does have. Im off to SEMA and the next route is FI for me better payoff in the end when I decide to do it. My numbers look interesting enough like this setup
crawford setup
11-02-2003, 08:33 AM
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Steve are you in?? 60 days your plenum and ECU should have a college education by them... I'll call Power Train to set up So Cal Dyno Day 2 ".The revenge of the unsettled " Jan 3rd 2004 What say you guys??? I thing we'll get a better rate this time...
Last edited by Mr Twisted; 11-02-2003 at 08:38 AM.