[QUOTE]Originally posted by 1stGenCRXer
[B]:eh: A mandrel bend is accomplished by inserting a mandrel the same size as your exhaust and using it to guarantee the inside diameter doesn't change. Are you thinking of crush-bent tubing? The difference between formed elbows and mandrel bends is so slight it's almost laughable.
but there is a difference, right? and since there is a difference, formed elbows are better. thank your for illustrating my point.
Let me put it this way. If it was so great, it would still be used in racing.
it is still used in racing. why? because it worked, and still works. If you want to talk about highly competative, look into the world of kart racing. It's gotten to the point in 4 cycle karting that high HP engines have about a 15* bend coming out of the head on an otherwise straight pipe.
is it a bend, or is the pipe set at a 15* angle?

when i registered to this board, i never read anything that said people can only speak about streetable engines.

and if you think i was belittling you, its your fault. you know what youre talking about and i would like to see your car make a run. but all in all, i can take a crx with its sohc vtec engine and make it run low 14's without ever putting an aftermarket part on the car. building sik qik cars is what i do.

 

read what you just wrote, read the very first 3 posts i made, than think about what you just wrote. i came here with no attitude and respected what other people said, til they started jumping on me like the black guy at a klu klux klan meeting. im a chill person too, i smoke too much not to be.

 

Perhaps you should consider your ability to take a suggestion. I'm trying not to be hostile here but you seem to be very quick to fall back on the defensive. You wanna smoke, great. Puff a bowl and relax, no need to be all high strung.

 

True there is a difference, that's all I'll say.The pipe is set at a 15* bend at the head on some headers, and bent to about 15* on others. Well that would be our fault then, wouldn't it. Here's a little hint then: If someone is talking about a theorhetical build, anything goes, if they're talking about a race engine, anything goes. For topics that don't fit those two, we normally double check on the intended uses before making suggestions. Personally I prefer sleepers, and BTW, CRX's didn't come with SOHC VTEC engines stock

 

I would suggest every one read "Scientific Design of Exhaust and Intake Systems" by Smith and Morrison.

The key to header design is pipe diameter and length matched to cam timing. Properly done headers will deliver a negative pressure pulse to the exhaust valve at opening enhancing cylinder scavenging. #bends and heat loss have very little to do with any but the most highly strung engines. Primary consideration is maintaining exhaust gas velocity.

 

I'm unsure of which advice to take on this point...

You came in with a 'my way or the highway' and a 'this is best' attitude. The fact of the matter is that there is never a 100% best solution. Every build, every application is different, and will require a different approach.

 

man im learning so much in this thread despite certain...things..



:bowdown: to the techies :thumbup:

 

If one has to ask, they haven't spent enough time "chatting" or conversing with others online. It's very easy to display feelings and have other people pick up on them, even through a screen. <--see

Cool, are you talking custom made parts or just tweaks with what's already there? I have a Prelude S with a F22 SOHC non-vtec that I don't want to put much money into right now cause I'm planning a swap sometime later on... but would love to get some more power out of it.

 

qtiger, ericks makes a good header, but if you follow their link to javiers head site, you will see why i said that. they claim larger valves, 5 angle or better, and p&p are detrimental to the honda's flow capabilities. which doesnt make any sense to me at all. and no i didnt come here with an attitude. i didnt bash anyones advice, simply added to everyone else's. i suggest to you to re-read my first 3 posts. now i could get really rude because you made a false statement, aka lie, but there is no need for it. just please re-read my very first post on this topic.

they didnt make si's with the vtec engines, yes, now i know. the car is pre-obd, and the first vtec appeared in 92 in obd-1 cars. well in that case, i can take the stock 1.6 and make it feel like it has vtec. in fact me and buddy just bench grinded his cam, while takin his head to the shop to get radius valve job done. then we got it back and p&p'ed it. had his valves heat treated as well. now we are about to drop the oil pan, pull out the rods, pistons, crank, work those over, and do an in-ca hone. and when i mean work the pistons, rods, crank over i mean-shot peen the rods, then zero out the rods and pistons, cut, balance, knife edge the crank, then put it all on a rotary balance and balance the assembly to 9000 rpms.

basically i love making cars fast, and when i talk tech, that is how i talk. i understand some people are satisfied making their car slightly faster than stock, quick off the line, or just fun to drive. but me, its not fun unless its fast, driving isnt proper unless your driftin, and racin balls to the wall in traffic should carry mandatory jail time.

 

How does he claim that P&P is detrimental to Honda heads? That is all he does! As for the 5 angle and larger valves, that has been clearly covered in the engine building thread and I will not reiterate here.

I believe this effectively sums up your arguments.