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gfrg88
07-09-2008, 08:57 PM
http://i19.photobucket.com/albums/b192/gfrg88/0617081019.jpg


what do you guys see wrong here??? the people with more experience let me know.. this is the fist manifold that ive actually built and people are telling me its not good enough :dunno:

labeledsk8r
07-09-2008, 09:00 PM
im still very noob on turbo manis but i would say the BOV is in a bad spot since the back presure is only on the 2 center exhaust ports ... the other outer ports have more pressure build up , im probably toatly rong or if im not i worded it rongly LOL

A18A
07-09-2008, 09:00 PM
the lack of whatever is supposed to be bolted on to that port under that round thing. and the missing nuts. and it's not on a a20a/b20a

seriously though i wouldnt have a clue

Civic Accord Honda
07-09-2008, 09:02 PM
ur missing a hose

gfrg88
07-09-2008, 09:07 PM
haha u guys are hilarious!!!

ok,
1. its not a BOV!!! its a WG(wastegate)
2. the dump pipe wasnt finished on there, it goes down onto the downpipe.

but yeah, labeledsk8tr kinda got it right.. everyone is telling me the wg is place wrong, but i dont know if it will really affect performance much... :dunno:

labeledsk8r
07-09-2008, 09:12 PM
haha u guys are hilarious!!!

ok,
1. its not a BOV!!! its a WG(wastegate)
2. the dump pipe wasnt finished on there, it goes down onto the downpipe.

but yeah, labeledsk8tr kinda got it right.. everyone is telling me the wg is place wrong, but i dont know if it will really affect performance much... :dunno:

wastegate w/e i just worrked 9 hours and am really really tired... how much boost are you planning to run on that? i would think lower psi wouldnt be as bad as higher

::edit:: i feel dumb now ... even if i am a turbo noob i cant belive i messed that up

gfrg88
07-09-2008, 09:29 PM
wastegate w/e i just worrked 9 hours and am really really tired... how much boost are you planning to run on that? i would think lower psi wouldnt be as bad as higher

::edit:: i feel dumb now ... even if i am a turbo noob i cant belive i messed that up

haha, its all good.. ive said dumb things before too without really thinking :lol:

planning on running about 12psi... whatever it takes to get to 11.5s no more than 15 pounds though... i thnk i have to relocate the wg.. i wasnt thinkng when i did that, i was more worried about turbo fitment and placing and crap...

Hans
07-09-2008, 10:31 PM
If I were you I'd also want to go with equal length headers. This allows the turbo to spool up with equal pressure from all 4 cylinders, thus decreasing spool-up time when. Someone correct me if I'm wrong.

AccordB20A
07-09-2008, 11:39 PM
i can see a turbo h22. thats not the wrong part. haha i had to look twice from what i was reading i thought you had a BOV installed where the WG was supposed to be.

gfrg88
07-10-2008, 06:47 PM
If I were you I'd also want to go with equal length headers. This allows the turbo to spool up with equal pressure from all 4 cylinders, thus decreasing spool-up time when. Someone correct me if I'm wrong.

yeah youre right.. but i didnt want to make it too complicated...

my brother took her out today, since i just came back out to cali last week. He said, DAMN!!! its fast :D it boosts up perfectly to 8psi and holds it. so it seems like everything is ok, and its stayin like this untill the engine doesnt like it anymore :rice:

MessyHonda
07-10-2008, 06:55 PM
when are u going to build the a20 manis?

bobafett
07-10-2008, 09:31 PM
wastgate placement is about as bad as it gets, and the collector is garbage.

however, the welds look okay, so if you were to design something better i'm sure you could pull off a good manifold.

the other main issue is that is it NOT an a20. ;-)

buy this book: http://www.amazon.com/Maximum-Boost-Turbocharger-Engineering-Performance/dp/0837601606/ref=pd_bbs_sr_1?ie=UTF8&s=books&qid=1215754201&sr=8-1

it is one of my current favorite. it has entire chapters on how to design and build turbo manifolds, and pros and cons of each design. its a very easy to understand book, and it constantly teaches me new things where I ask my self "it seems so obvious, why didn't i think of that?"

keep up the good work, just gotta work on getting the right design.

Oldblueaccord
07-10-2008, 09:36 PM
Yeah I missed the H22 part entirely.


wp

bobafett
07-10-2008, 09:43 PM
and just so i am not being totally useless in my post, an ideal wastegate position will allow venting from all runners, so the best place to put it somewhere in the collector.

as for the collector its best to try something like this:
http://www.p1-performance.com/files/4merge.jpg

gfrg88
07-11-2008, 04:43 PM
well it seems to be doing the job right now.. next, year itll be a different car.. or rebuild the engine, with high CR and turbo :D

TWOLOUDNPROUD
07-13-2008, 02:58 PM
What are you going to do with the old manifold? do you want to sell it?

http://i19.photobucket.com/albums/b192/gfrg88/0209081612a.jpg

gfrg88
07-13-2008, 11:09 PM
What are you going to do with the old manifold? do you want to sell it?

http://i19.photobucket.com/albums/b192/gfrg88/0209081612a.jpg

sold it already.. sorry bro..

Accordtheory
07-14-2008, 02:42 PM
http://i19.photobucket.com/albums/b192/gfrg88/0617081019.jpg


what do you guys see wrong here??? the people with more experience let me know.. this is the fist manifold that ive actually built and people are telling me its not good enough :dunno:

Well, if it works, it works, but I can give you a few pointers..
Fab work doesn't look bad, I would have been curious to see a close up of that before it got coated.
Well, your wastegate placement is not ideal, it should be at the intersect point of all 4 runners for a single scroll, or intersect between the 2 runners for a twinscroll, with a divider wall up to the gate, or 2 separate gates. (another day..) See where you have the 2 runners coming down to the turbo flange, after the intersect point of the tubes, the gate should attach right there on the outside of the radius, close to the flange. The way you have it, most of the exhaust going through the gate is coming from the 2 inside cylinders. Provided that you are actually able to attain the desired boost level without creep, you'll still have a little different exhaust backpressures for the different cylinders, which leads to diffferent a/f ratios and octane tolerances, and a little more conservative tune..not that big of a deal though.

Usually what will happen with wastegate placement like that which can be a big problem is boost creep, the wastegate simply won't be able to bypass enough air to control the boost, and it will increase dramatically with rpm. The problem is exacerbated by large turbine housings, since the manifold backpress will be lower, there will be less differential pressure across the gate, making it harder to bypass enough air.

What is the deal with the 2 runners going into the flange without joining together first, is that a twinscroll? If it is, you have the wrong cylinders paired together..you're trying to get firing impulses to be evenly spaced to each side of the turbo..in other words, every 180 degrees, one side gets an exhaust pulse, then the other side gets a pulse. To illustrate what I mean, look at how the cylinders are paired up on a typical 4-2-1 honda header, it's the same.

Hope this post helps you out a little..

gfrg88
07-14-2008, 11:42 PM
What is the deal with the 2 runners going into the flange without joining together first, is that a twinscroll? If it is, you have the wrong cylinders paired together..you're trying to get firing impulses to be evenly spaced to each side of the turbo..in other words, every 180 degrees, one side gets an exhaust pulse, then the other side gets a pulse. To illustrate what I mean, look at how the cylinders are paired up on a typical 4-2-1 honda header, it's the same.

Hope this post helps you out a little..

fuk, damn.. so this manifold is pretty much garbage then.. i never thought about the pairing cylinders shit... damnit, yeah thats right i paired them wrong... im gonna have to build another one soon...

Accordtheory
07-15-2008, 08:52 AM
Do you plan on running 2 gates or a divided collector to a single gate on the new setup?

Also, what kind of welder are you using, and what type of metal did you use?
Did you backpurge?

AccordEpicenter
07-20-2008, 10:20 AM
it looks pretty good except as somebody said the wastegate placement sucks. Id run it as is, and if if you have boost creep or spiking id move it around a bit. Ive seen worse but ive seen better. Anything is better than a log, esp when people build logs with the wastegate on one end and the turbo on the other end... gayyy. Prolly the worst commercially available manifold ive seen was those homo drag manifolds, with the wastegate primarily venting cyl 1 and not much else. Piss poor.

gfrg88
07-20-2008, 10:59 AM
http://i19.photobucket.com/albums/b192/gfrg88/Dyno1.jpg

need to tune it more... was running really rich..