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Vrooom PSHHHH
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harmonichonda has it and I believe took part in the development of it. I saw a dyno chart of it not too long ago and it was basically like stock in the low and mid-range but it carried power a good but further, it just kept climbing after where stock power usually drops off lol
 

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bangin' gears
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i still dont get why people use DH. I understand he used him but why? He has a crx that makes 300whp and it still runs 11's.....
 

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yea i saw that crx. the topmount kinda seems like a stupid setup. I wonder how it would do with turbo setups
huge gains in torque, period, weak ass motor like mine with 173ft/lb on first run, stock block still. God I hope the next one goes even better

I use dave's stuff because I like it and trust him; sorry if that really offends somebody as I have read the stuff on honda tech way back. I've had more nonsense with other more reputable places and atleast with dave, things get here, he can carry on a conversation about his ideas and pushes things through that may seem radical or like the comment above saying it looks like a stupid setup, etc etc. Go with who you trust but despite the stuff about him on honda-tech it has been nothing but great results and advise between here and dh-racing.
 

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bangin' gears
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huge gains in torque, period, weak ass motor like mine with 173ft/lb on first run, stock block still. God I hope the next one goes even better

I use dave's stuff because I like it and trust him; sorry if that really offends somebody as I have read the stuff on honda tech way back. I've had more nonsense with other more reputable places and atleast with dave, things get here, he can carry on a conversation about his ideas and pushes things through that may seem radical or like the comment above saying it looks like a stupid setup, etc etc. Go with who you trust but despite the stuff about him on honda-tech it has been nothing but great results and advise between here and dh-racing.
maybe he should try it on his own race car then. I hope you plan on racing your car at the track so we can see what it can do cuz some dyno numbers arent saying anything.
 

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maybe he should try it on his own race car then. I hope you plan on racing your car at the track so we can see what it can do cuz some dyno numbers arent saying anything.
not building a race car here, and maybe you should call him and say such challenges seems pretty dumb to type it on a forum; you should know that with all the comments you've made over the years in similar manners
 

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i really dont see how that thing can do much at all. it has practically zero plenum volume, and a very small gap for airflow between the plate and the manifold for runners 1 and 4. i think its definitely safe to assume that its kinda asking for engine damage, seeing as how cyls 2 and 3 will run a very large amount leaner than cyls 1 and 4, and not by the same amount universally, but by varying amounts throughout the rpm range, making it impossible to tune properly for.

the idea is a good idea, but the design i see in those pics looks horrible for replicating the idea. if it stood about 6 inches higher, then i would have nothing but good things to say about it. but it doesnt, it's like right there almost touching the runner openings.
 

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hmm guess i didn't put up the pictures, but the IM itself was ported out also, there are no longer 8 holes on top, 4 larger ports rather and the interior of the plenum itself was designed to give equal to all 4. The head was designed to coordinate with it as well, the entirety of the project flowbenched.
 

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i hate flowbenches. while they do a good job to tell you if a single runner flows similarly to the other runners, they are completely unable to test more than a single port at a time with seperate results for each port. flowbenches also test by blowing constant air through them. which has nothing to do with anything because thats not even remotely close to how an engine works. what needs to be tested but there isnt a machine for yet, is pulsed flow alternating from cyl to cyl in the exact fashion that an engine would pull the air.
flowbenching a single manifold by itsself is fine so you can see how even each port is for flow/restriction. but there is no way to test how the manifold/plenum/TB combo will actually perform on the actual engine, it simply cant be simulated and measured accurately by any means
 

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i hate flowbenches. while they do a good job to tell you if a single runner flows similarly to the other runners, they are completely unable to test more than a single port at a time with seperate results for each port. flowbenches also test by blowing constant air through them. which has nothing to do with anything because thats not even remotely close to how an engine works. what needs to be tested but there isnt a machine for yet, is pulsed flow alternating from cyl to cyl in the exact fashion that an engine would pull the air.
flowbenching a single manifold by itsself is fine so you can see how even each port is for flow/restriction. but there is no way to test how the manifold/plenum/TB combo will actually perform on the actual engine, it simply cant be simulated and measured accurately by any means
I always wondered why people put there manifolds on a flow bench when you're dealing with pulses.
 

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I always wondered why people put there manifolds on a flow bench when you're dealing with pulses.
not even just the whole pulse thing, but the whole engine characteristic thing;
people seem to think if a mani can flow more air, it will make more power. inconsistent edges, varying diameters, and sharp curves will all obviously lower the potential airflow. so flowbenching runners before and after doing a street port type portjob where all you do is smooth all inconsistencies is a good idea to see just how much difference it made simply by smoothing things. but flowbenching doesnt mean squat when doing major portwork. all a flowbench measures is how much air can get through before it starts getting restricted. and obviously bigger diameter will allow more airflow on a flowbench. so runners that are short as hell, huge in diameter, and as smooth as possible, will flow the best on a flowbench. but that is very rarely the case of what will make the best power. anyone that knows anything about custom manifolds or majorly re-working a stock type manifold, knows that you need specific diameter runners and specific length runners to make the best power in specific rpm ranges. while bigger flows more air on a flowbench, bigger will often cause a loss of power due to the loss of velocity.
and back to the pulse thing; power comes from the combination of airflow and velocity, and when the pulses create the highest pressure at teh valve head. the pulses themselves also have a huge effect on the airflow, and on the velocity. making good power requires proper airflow, proper velocity, proper strength pulses, and properly timed pulses. altering one of these things has a huge effect on all the other things, usually in a bad way, sometimes in a good way, sometimes barely noticeable. and considering a flowbench can only measure airflow under constant air flow, it's pointless, its stupid.

simple basic street port on a stock manifold: flowbench gets an A+, for telling how much better everything flows all still being the same exact sizes but without any inconsistencies/irregularities/flaws.
anything else, anything else at all: flowbench is just a paperweight

for the manifold thing pictured in this thread, of course a flowbench will say it flows better, look at where the TB is. the flowbench measures how much air IN TOTAL is passing through all 4 runners under constant consistent airflow. runners 2 and 3 are going to flow buttloads of air. what the flowbench wont tell you is that runners 1 and 4 are flowing less than stock, and runners 2 and 3 are flowing 400% more air than runners 1 and 4. meaning IN TOTAL yeah it probably flows more air than a stock manifold, but re-read the previous sentence...

using the thing in the picture would be like using 40mm ITB's with no filters on cylinders 2 and 3, and 20mm ITB's with tiny paper filters on cylinders 1 and 4
 

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Back 2 Hackin
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i still dont get why people use DH. I understand he used him but why? He has a crx that makes 300whp and it still runs 11's.....
Arent you the same person who claims that whp are just arbitrary numbers?





On another note, is there even a DOHC Crx out there, arent they all SOHC, so considering getting a CSX to 11's isnt bad at all IMO.

I dont particualary follow the CRX crowd, but my friend does, and I hear alot about the CRX movement from him.

Also, about the original topic. The only thing I see worth wild about that is the lower plennum volume on it. On a stock engine, or N/A application I think it might be worth it, rather than porting out your IM.

For a turbo application, is the only thing I would imagine, it might fail with.

All in all its not a bad Idea.
 

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well the crx dh-racing claims to have is a h22 swapped crx,,,, and it is cool if ur car only makes 150whp on the dyno and runs 11 sec times... it is un cool if ur car makes 300whp and only runs 11sec times...... but you are right the numbers mean nothing i just would be ashamed to claim 300whp in a crx and only run 11sec times
 

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Back 2 Hackin
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Well, how many ludes do you know of that have 300 even 400 whp that dont even touch on 11's.

The only diffrence between the 2 cars now is the curb weight.
 

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Well, how many ludes do you know of that have 300 even 400 whp that dont even touch on 11's.

The only diffrence between the 2 cars now is the curb weight.

that for one the curb weight is alot different
and if a prelude has 300whp n/a,,,it should get 11sec passes
 

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Back 2 Hackin
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Well, you just said yourself, that whp is irrelevant.

Frankly looking at it like this. Whats the fastest running prelude that we know about? Its either MD23vtec or Oaks Racing. Out of the 2 of them, they both have about 800 whp IIRC. And they are breaking 10's.

So you mean to tell me that having another 500 whp will only offer up 1 more second at the track vs a 300 whp lude? Mabey, it really doesnt matter.

And IIRC the curb weight isnt that big of a factor. What is the estimated weight vs time ratio? 100lbs = 0.01 seconds?

So if you have a car that is 3000 lbs vs a car that is 1900 lbs(using the lowest weighted stock CRX vs a stock fifth gen prelude weigth) were talking a whole whopping 1.1 second.

And the rest would vary on driver skills, and other various random elements.
 

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bangin' gears
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Well, you just said yourself, that whp is irrelevant.

Frankly looking at it like this. Whats the fastest running prelude that we know about? Its either MD23vtec or Oaks Racing. Out of the 2 of them, they both have about 800 whp IIRC. And they are breaking 10's.

So you mean to tell me that having another 500 whp will only offer up 1 more second at the track vs a 300 whp lude? Mabey, it really doesnt matter.

And IIRC the curb weight isnt that big of a factor. What is the estimated weight vs time ratio? 100lbs = 0.01 seconds?

So if you have a car that is 3000 lbs vs a car that is 1900 lbs(using the lowest weighted stock CRX vs a stock fifth gen prelude weigth) were talking a whole whopping 1.1 second.

And the rest would vary on driver skills, and other various random elements.

ive tried to be nice to people but you just never seize to amaze me. I dont know how many threads i have read and you have posted in that have just flipped it upside down and ruin it because you just dont get it.

you think outside of a broken box.
 

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Back 2 Hackin
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you think outside of a broken box.
or so you say

dont be mad there sir. I see you post a lot of crap that contradicts yourself, and you give people a hard time.

You are always claiming how whp is arbitrary numbers, but you still use these arbitrary numbers as so called weight to talk down on something, in this case the 300 whp crx.

And do not refer to me as "You People" I have a name
 
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