What size of injectors should I use?
#1
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What size of injectors should I use?
Im going to be running a stock s4 t2 turbo, with full 3" exhaust and ported WG (35-40mm) along with a 3" TID. ported manifolds.
This is all on a high compression streetported NA motor. (for my turbo project)
I am planning on running a Maximum of 10PSI for the time being.
Should i Just get 4x720cc's? I heard the SAFC2 cant effectively control anything larger than that, i *think* i could go with 550's but its easier to tune fuel down, than up...
Any input would be great.
And another side question just for the hell of it..
Where do most guys with the stock turbo make their power? I notice my car right now, as an Na, makes its power above 4k RPMs and before that its pretty slow..
This is all on a high compression streetported NA motor. (for my turbo project)
I am planning on running a Maximum of 10PSI for the time being.
Should i Just get 4x720cc's? I heard the SAFC2 cant effectively control anything larger than that, i *think* i could go with 550's but its easier to tune fuel down, than up...
Any input would be great.
And another side question just for the hell of it..
Where do most guys with the stock turbo make their power? I notice my car right now, as an Na, makes its power above 4k RPMs and before that its pretty slow..
#2
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You could probably scrape by with 550's but they are going to be nearly maxed, with 4 720's properly tuned on the safc I think your afrs would be pretty happy. Not to mention if you go with that setup it gives you a bit of overhead in case you get bit by the speed bug that decides you need to run 12-14lbs one of these days
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#3
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Originally posted by pip
Not to mention if you go with that setup it gives you a bit of overhead in case you get bit by the speed bug that decides you need to run 12-14lbs one of these days
Not to mention if you go with that setup it gives you a bit of overhead in case you get bit by the speed bug that decides you need to run 12-14lbs one of these days
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But I dont know If i wanna run that much boost with high compression rotors, ill really have to monitor my **** to keep from destroying my engine..
#4
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I wouldn't think you'd need 4 720's, but you're right it is easier to tune down. My plan is to run 550cc primaries and 720/850cc secondaries on my current setup, and with a walbro, then getting a streetport later. I'll be data logging my a/f ratios to make sure it doesn't get too lean but I'm pretty sure I should be safe. I talked to SonicRat about his turbo'd n/a setup, here's a quote from it. Granted his setup doesn't have a streetport, but take it as you will:
"I go no higher than 12.0 past 4K rpm @ 10psi. 550/720's w/walbro 255 & RRFPR & an s-afc. Seems fine so far!"
Oh yah and my plans are to run about 12-13 lbs.
"I go no higher than 12.0 past 4K rpm @ 10psi. 550/720's w/walbro 255 & RRFPR & an s-afc. Seems fine so far!"
Oh yah and my plans are to run about 12-13 lbs.
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Oh yah, you could also do something like 680cc primaries 720cc secondaries, or 4x680's, or 550 prim 850 second, etc. All of those are less than 4x720's but more than 550 prim 720 second, so you have other options too. Also, I'm not sure that an s-afc could hand 4x720cc extremely well, I've heard that it CAN but it's cutting it close. I may be wrong, though.
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Well, since the turbo is generally only spooled for about 1000rpm before the switchover, I didn't find a need to go past the 550's in the primary position. I generally don't see higher than 12.2 at WOT from 2krpm to 4k, and that's with a pretty decent ammount of negative correction.
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Ok, It sounds like a more suitable setup would be 550primary 720 secondary. Thx for the input DD and sonic. btw sonic, do you have any pictures of your setup, just like general pics of the engine bay or something?
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DESERE, I am running 550cc all around on my 6 port Turbo T62. However I have it set for 8 lbs of boost with a 40mm wastegate. I generate most of my power after 4000 rpm. Before that it runs like a normal N/A would in 1st gear. Between 6000 rmp and 8000 rpm it spools super fast throughout gears. I have to watch the RPM otherwise I will over rev it.
On another forum "HONDAKILLER" (who has a setup like ours with a microtech) just blew his motor last week when he reached 15 PSI.
Here are some pics of my setup
http://img78.photobucket.com/albums/...r_on_hoist.jpg
http://img78.photobucket.com/albums/...port_turbo.jpg
http://img78.photobucket.com/albums/...tor_in_car.jpg
On another forum "HONDAKILLER" (who has a setup like ours with a microtech) just blew his motor last week when he reached 15 PSI.
Here are some pics of my setup
http://img78.photobucket.com/albums/...r_on_hoist.jpg
http://img78.photobucket.com/albums/...port_turbo.jpg
http://img78.photobucket.com/albums/...tor_in_car.jpg
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It is for a FD OBX/HKS style. I have no issues with clearances (LIM, Wastegate, Chassis.
I hope the pic helps.
http://img78.photobucket.com/albums/...otor_turbo.jpg
I hope the pic helps.
http://img78.photobucket.com/albums/...otor_turbo.jpg
#12
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Another question, I noticed your TB adapter, I used to see those on ebay but don't anymore. Is that where you got yours or do you know of somewhere else that sells them?
Glad to know the aftermarket manifolds out there clear the LIM that well, I'm assuming you didn't have to use any spacer either, right?
Glad to know the aftermarket manifolds out there clear the LIM that well, I'm assuming you didn't have to use any spacer either, right?
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Originally posted by DEZERTE
Thats a CRAZY big turbo your using with the NA engine, damn... nice pictures. Im planing on running the stock EXM with the Flange spacer.
Thats a CRAZY big turbo your using with the NA engine, damn... nice pictures. Im planing on running the stock EXM with the Flange spacer.
I was planning on that too, but I like this idea better. Seems that there are no clearance problems at all, either with the LIM or the fender. Granted with an s4 turbo there supposedly wont be as many clearance problems near the fender as with the s5, but I just won my s5 turbo off ebay and would rather have that one anyways. That manifold seems like it'd be a lot nicer than a spacer, of course way more expensive.
#15
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Originally posted by stacher
It is for a FD OBX/HKS style. I have no issues with clearances (LIM, Wastegate, Chassis.
I hope the pic helps.
http://img78.photobucket.com/albums/...otor_turbo.jpg
It is for a FD OBX/HKS style. I have no issues with clearances (LIM, Wastegate, Chassis.
I hope the pic helps.
http://img78.photobucket.com/albums/...otor_turbo.jpg
Is this the one you're using?
http://cgi.ebay.com/ebaymotors/ws/eB...category=33742
#16
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dDUB, Yes, that is the one. I got myne from E-bay as well but only paid $100. To specify and correct myself I said "I have no clerances issues" but that is because I used a spacer from the exhaust to the exhaust manifold. Sort of what aaron cake used but smaller. Two of the plates would of worked but it would of been to close (for me) to the LIM. This way I have about 1 1/2 - 2 inches. Something else to think abou....you will need longer studs. I used 2 3/4 long.
Ok...I don't want to steal the thread from DEZERTE, however if he keeps asking questions I will keep replying.
http://img78.photobucket.com/albums/...ust_spacer.jpg
http://img78.photobucket.com/albums/...st_spacer1.jpg
Ok...I don't want to steal the thread from DEZERTE, however if he keeps asking questions I will keep replying.
http://img78.photobucket.com/albums/...ust_spacer.jpg
http://img78.photobucket.com/albums/...st_spacer1.jpg
#19
what are you using to control these? if you're just using the stock ECU + an SAFC, I'd reccommend 460CC primaries and 880CC secondaries.. I've tried to start a n/aTII with 4x550CC injectors and it ran great but was a BITCH to start because of the extra fuel.. SAFC can't control crank fuel amounts
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SonicRat...Yes, it has been in since April. Right now I have about 1 in clearance. If I would of made my exhaust spacer a little smaller I would of had more space. If I would of used a smaller Turbo i would of had more clearance too. So far it has never hit the fender.
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Does anyone know if you can use that manifold with a s5 turbo and add a wastegate? And the listing say its supposed to fit an FD, but from what im seeing itll go in an FC?
#23
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Originally posted by RylAssassin
Does anyone know if you can use that manifold with a s5 turbo and add a wastegate? And the listing say its supposed to fit an FD, but from what im seeing itll go in an FC?
Does anyone know if you can use that manifold with a s5 turbo and add a wastegate? And the listing say its supposed to fit an FD, but from what im seeing itll go in an FC?
Originally posted by stacher
It is for a FD OBX/HKS style. I have no issues with clearances (LIM, Wastegate, Chassis.
I hope the pic helps.
It is for a FD OBX/HKS style. I have no issues with clearances (LIM, Wastegate, Chassis.
I hope the pic helps.
Yes it is for the FD and fits the FC just fine.
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I didn't use a turbo from an S5, however mine is bigger, I used a spacer and I used a HKS Standard wastegate. The view of this picture is from under the car.
http://img78.photobucket.com/albums/.../wastegate.jpg
http://img78.photobucket.com/albums/.../wastegate.jpg