TeamCapri

General => General => Topic started by: randyshear on June 01, 2009, 10:26:00 PM

Title: Boost control & rocketchip, please help me understand them....
Post by: randyshear on June 01, 2009, 10:26:00 PM
I have been researching turbos for the last several hours.. I have never had one, so I know nothing about them.. After research I have a much better understanding, but have a couple Qs.. Did Rocket design the rocketchip? LOL j/k that answer is obvious.. I have been looking at a few manual boost controllers.. Do the capris come with stock boost control (besides the waste gate LOL)or is this an aftermaret kit? It looks like boost controllers are aftermarket for all turbo cars.. Also am I understanding correctly that with the boost controller I will need a chip / EEPROM flashed to disable the fuel cut off and increase boost to 16PSI? (ie Rocketchip) How much boost does a stock capri push on average with no chip & no controller? What kind of HP gain can I expect from adding a controller & chip? How much boost will I be able to push with the stock setup, with only adding a chip & boost control?  Lastly.. How much boost can I SAFELY push with the controller & chip to avoid damaging the internals. Thanks guys!! I appreciate all your help.. I'm new to this site, and to TURBO...
Title: Boost control & rocketchip, please help me understand them....
Post by: moot on June 02, 2009, 04:08:00 AM
you can push 16 with the controller and chip internals should be fine
Title: Boost control & rocketchip, please help me understand them....
Post by: Gus Kelley on June 02, 2009, 07:07:00 AM
Hey Randy! When you buy a stock turbo capri it will boost 6-8 lbs. The boost controller interupts the pressure going to the waste-gate controller. The boost controller is adjustable, allowing you to adjust max boost obtained while driving. If you choose to run over 10-11lbs then a plug set-up in the engine compartment, on the firewall, behind the intake needs to be dis-connected. This controls an over-boost circuit that mommentarily shuts down the engine. the factory computer module not "mapped" for good fuel ratios above 11lbs boost. The car will lean out and will start to burn pistons for one problem and it only gets worse from there. The "Rocket-chip" is a re-mapped computer module that has the fuel ratios altered to run in the 11-1 range when above 11 lbs boost. This along with running the proper high octane gas should keep your engine together up to 16lbs boost. The Rocket-chip is mapped to allow good fuel ratios up to 19 lbs boost and is con-figured to raise the RPM red line above 7000 revs. Our stock turbos will boost to above 16lbs but do not sustain that. They start to die off. There-fore some have had custom turbos built using the stock exhaust side and the cold side of a vj-11. This gives a little more cfm in air-flow and the boost comes on a few rpm sooner almost gives a full 16lbs boost to redline in the upper gears. If you follow rocket and rci's posts, they talk a bit about other turbos. These are larger still but require custom exhaust manifolds.  Hope I answered a few questions and I'm sure others will pipe-in more comments.  Gus
Title: Boost control & rocketchip, please help me understand them....
Post by: randyshear on June 02, 2009, 08:41:00 AM
That info was very helpful. Thanks. I can't get ahold of the guy about the XR2 in Kansas City.. It's driving me crazy.. I am going to bump it up to about 16PSI, and buy the rocket chip. I really don't need more than that for now. Do you know what HP gain I will get bumping it to 16PSI, and adding a cone air filter to replace the restrictive stock box? Later on I will add a bigger less restrictive cat, and probably have some custom exhaust work done from the turbo back.. Thanks Gus, you're a big help!
Title: Boost control & rocketchip, please help me understand them....
Post by: Rocketman on June 02, 2009, 09:35:00 AM
Its  best to get an exhaust & intake along with the Rocketchip & boost controller, you'll see the best HP gains there. Also look to replace your bypass valve with an aftermarket bypass or blowoff valve.

You will see an extra 20-30hp depending on your setup, Yuri dyno'd in 151whp and 170ft-lbs of torque with a intake, exhaust, and chip if I remember correctly. I've had a customer with a pretty extreme setup make 190hp on a stock turbo, though he was pushing it over the safe 16psi limit.

-Rocketman
Title: Boost control & rocketchip, please help me understand them....
Post by: Gus Kelley on June 02, 2009, 11:36:00 AM
Hey Randy! On my silver Janis, I've run best two passes of 13.80s at 101-103mph. I have 21/2 exhaust from down pipe to back, drilled out air box, boost controller from tunerfixx set at 15lbs and re-mapped ECU and bigger tires(195-15-55). I burned that motor 2 weeks later while on the freeway opposing a Subie at 135-140mph.  Gus
Title: Boost control & rocketchip, please help me understand them....
Post by: Gus Kelley on June 02, 2009, 11:40:00 AM
Hey Randy! Also I've ridden in rockets car, quite impressing for horse power. It was a little nervy as the roads were icy and and we were in tight quarters road wise.  Gus
Title: Boost control & rocketchip, please help me understand them....
Post by: rcicustoms on June 02, 2009, 03:37:00 PM
ok, in all my experiences with 4 b6t engines in the festiva and 2 in the red capri...
this is what ive come up with....
with the stock ecu, turbo and injectors. and a walbro 255 pump. (sorry we defaultly allways put walbro pumps in our turbo cars first thing. sooo...all my experiences fall within having made that mod...) ive pushed 14psi and we cooked the first turbo on the festiva...it looked like an stove reamer, after a bearing went and put the coldside wheel into the coldside...
 
*festiva engine 1 turbo 2*...we found at the time that reich racing made an ecu for the b6t. so that was the next mod (you see we didnt know rocket or of rocketchips in 2007) then we found the corksport downpipe.. well little known to us were the modifications needed to run the downpipe...one of the modifications needed was to trim out the wastegate hole ...we didnt do that and the car stuck a wastegate in the downpipe (wouldnt open all the way) and our wastegate set at 17psi became 24psi in all high gears...and poof within 3 weeks we lost cylinders #2 all at once....
* festy turbo 2 engine 2* at this point we had the reich ecu, corksport downpipe, hard pipes a blitz bov and 18psi holding strong. the car was a rocket ( no pun intended) on this motor and setup, the 1800lb.festy with brians 200lb ass in it. ran a 12.5 at a stupid 109mph with rubber in the first 3 gears .... by fall our beating on a b6t with over 170,000 miles cought up with us...  one night just playin arround with the capri vs the festy.. (not fair my capri was on the dreaded 14psi mark with a stock ecu)
the festy tossed rod # 3 through the back of the block and oilpan...( i got to watch this take place.. about a car lengh behind and to the right of the festiva. it shot flames and sparks over 6 feet behind the car.. and i had a passenger that to this day i swear shit himself...)

*festy engine #3 turbo #3* ...yea engine 3 lasted about 10 minutes after startup and lost a piston at idle heating up (dont buy motors off the 323 performance forum, even if the guy says it has 50,000 miles on it)
 
*festy engine #4 turbo #3* at this point brian had started his new project, and was looking for an engine to put in the festy just to sell it.. i wasnt thinking, and i sold him the engine i had just harvested from my 88 323gt. and large rods and all went down the road....

*capri xr2 engine 1, and turbo 1, still on turbo 1* ok i had great luck with my first engine..
it lasted and accepted all mods i have done.
so ill just tell ya what did her in...

setup: corksport ecu, stock injectors,walbro pump, corksport downpipe, aftermarket hardpipes and j pipe, 2.5 inch high flow exhaust...

i got greedy and wanted to beat a supercharged fox mustang, so i bumped the psi to 21, and had no wideband to reference...
from what i can gather after tearing down the blown motor. the injector duty cycle tops out at 100% at arround 20 psi on the vj-11 and #1 being the last injector to see fuel leaned out enough to cuase a bad pre ignition scenario, and the engine pushed the piston through this explosion and cooked the right side exhaust valve too...

sooo i built the high compression ...
im currently running the same setup with dsm 450cc injectors, and the na high compression block.
im pushing 18psi everyday. and the afrs are staying at rich levels all the way through the
rpm band in all gears. the car pulls alot harder than the b6t did on 20 the night she blew ...

the new engine has a tightness ,a snappyness it never had on low compression... and a bit more rumble and breakup when you coast in gear up to a redlight. or slowing down it pops and snarls a bit more downshifting... and id say it spools about 250 rpm faster in all situations ( from dig ,, on off throttle,, and power downshifts on the highway...
of all the mods ive done, the one that yields the most gain, is by far the corksport downpipe.. im gonna say 30+ hp gain weather modded to the hilt, or just mildly modded, it will put a big shit eatin grin on your face..

the stock wastegate will not limit the car to 8psi with the cs downpipe, it jumps to 10 no matter if you run a hose to wg from intake with no boost controll it will hold 10psi....
Title: Boost control & rocketchip, please help me understand them....
Post by: Gostlrs on June 02, 2009, 05:15:00 PM
lets confuse him even more and start talking about dual boost controllers and getting electronic ones...LOL
Title: Boost control & rocketchip, please help me understand them....
Post by: rcicustoms on June 02, 2009, 06:07:00 PM
no no , just scenarios and statistics no part descriptions they already answered that above ...hehe...
Title: Boost control & rocketchip, please help me understand them....
Post by: Gus Kelley on June 02, 2009, 07:42:00 PM
Hey RCI!  Were you able to watch AFRs on the reich module? I still think that caused my piston melt. I've installed a gauge. I also have a higher volumne fuel pump, not a walbro and is rated at 190mlh not 240mlh. Also I agree about buying from the fairy forum. Russ at cougar bought a turbo from a guy known as "fastiva 608" I believe. He's frequently on that forum and represented it as a near fresh rebuild. As Russ stated it was a pile and it took him months of hunting the C sucker down with assistance from several of us on this forum. This all occurred just before your joining of this forum.  Gus
Title: Boost control & rocketchip, please help me understand them....
Post by: rcicustoms on June 03, 2009, 02:10:00 PM
unfortunately no, it prolly would have saved us face... but without what we done we wouldnt know now what to do...so it helped us learn, so im not gonna complain...

how many psi of boost were you running when it went???

we found the stock injectors to only be any good to about 19psi, and thats on the tiny vj-11..
with a real turbo i can only imagine that it would lean out earlier having more to do with flow than psi....

i would highly recommend fuel pressure controll
(adjustable FPR) and the dsm 450cc units.. you will need to make and run a resistor box.. but i have the radioshack part descriptions if you want to make one. also i have no problem telling ya how to wire it ...

PS.. the car will not even run on stock fuel pressure on 450cc units... you will need to turn the pressure down.. ive found 28psi to work well
Title: Boost control & rocketchip, please help me understand them....
Post by: Gus Kelley on June 03, 2009, 04:40:00 PM
Hey RCI! I take all intelligence highly. I've been told to run injectors from a RX7 N/A. I wouldn't need any electrical mods. Another words they are the same impedence? I have so much to learn as far electronic fuel injection and some to learn on turbos. As I've said before, I'm old school of carbs and rotor blowers.  Gus
Title: Boost control & rocketchip, please help me understand them....
Post by: Rocketman on June 03, 2009, 04:57:00 PM
There are high impedence DSM injectors arent there? I have a set laying around I'll test them.

I dont like dropping the fuel pressure like that...it screws with the spray pattern and who knows what else.

Once I figure out how to remap the ECU for larger injectors i'll let you know.
Title: Boost control & rocketchip, please help me understand them....
Post by: Gus Kelley on June 03, 2009, 05:56:00 PM
Hey Rocket! One set is high and the turbo is the other.  Once I get my car together the way I want it, I might entertain hauling to you and leave it for a week or so. I then can visit my grand-kids in Nashville. Maybe that would be enough time for you to burn a chip.  Gus
Title: Boost control & rocketchip, please help me understand them....
Post by: Rocketman on June 04, 2009, 10:40:00 AM
Sure just let me know we'll figure it out  (http://smile.gif)
Title: Boost control & rocketchip, please help me understand them....
Post by: rcicustoms on June 06, 2009, 08:52:00 PM
well we went out tonight, and took the capri out on the highway..its a cool dry night here...
 
on 30 psi fuel pressure,
 on the dsm units,      
at 17 psi, 5500 rpm, my afr was an 11.6
at 18 psi, 6000 rpm, my afr was a 12.2
at 19 psi, 6500 rpm, my afr was a 12.8
and at 20 psi just before redline (i let out at 7000 rpm)it hit a 12.6 ... witch means i hit the top of the turbos efficientcy and it actually got a hair richer cuase the turbo couldnt keep up...

and to think im doing this on a high compression N/A block...
 with just a corksport tune and
old fashion- listen, drive, frig, listen, drive, frig.. tuning... all i have is a base map, an adjustable FPR, and a boost controller. to tune with. and i know im losing power becuase im stupid rich thru the rpm band . but im pushing 20 psi on a na block. rich is safe.. ill change my oil if i get cylinder wash. as opposed to try to convince the wife i need another motor for my "cheap" toy...

oh and rocket, all the first gen (blue top) DSM injectors are low impedance.. but a resistor box is simple to make from 10.00 worth of crap from radio shack...

and gus, yes i looked at the rx7 injectors and yes there high impediance.... plug and play
but i believe there 380 or 400 cc units and i got a good deal on a spotless set of 450s
 
we had a project b18 civic turbo dynoed last week at 320whp.. with dsm 450 units so im not gonna run out of fuel with the bigger turbo im putting on soon...
Title: Boost control & rocketchip, please help me understand them....
Post by: randyshear on June 07, 2009, 12:43:00 PM
Well I am about to be on my way to pick up the XR2.. I will need the boost control & the chip. This is going to be fun.. I will have to pace myself, I can't overspend.. LOL..
Title: Boost control & rocketchip, please help me understand them....
Post by: Gostlrs on June 07, 2009, 05:34:00 PM
thats what i am doing as well. i am doing the supporting mods first before raising the boost. i have already put on a FMIC and Intake. Exhaust is next then gauges. after that i will get the boost controller and bump it to about 10 PSI then get the rocket chip and go all out
Title: Boost control & rocketchip, please help me understand them....
Post by: rcicustoms on June 08, 2009, 04:46:00 PM
rocket... i got on rc engineering and injectordoc sites.. and they say spray pattern is unaffected by pressure, and is built into the injector pintle... the flow rate is most effected by pressure and is why they say each psi fuel is equal to 10 cc flow ...
 for example if you were to obtain a 450cc injector which is rated at 450cc at 45psi and you run 50 psi your essentially running a 500cc injector... or 500cc fuel will flow out the injector each minute...450cc/min +5psi = 500cc flow...the other factor being pulsewidth is controlled directly by the ecu...

can pulsewidth be tuned for certain rpms at certain loads??? or is that preset into the ecus base map???

so essentially im running a 450cc injector rated at 450cc at 45psi and ive turned it down to 30 so im running a 300 cc flow per minute estimated.
more than likely higher, becuase my psi guage is located on the rail near #1 injector it reads how much pressure the #1 inj.sees so pump pressure should be higher ...ill sit down and do the math sometime and let you know more about the setup....Joe
Title: Boost control & rocketchip, please help me understand them....
Post by: Gus Kelley on June 08, 2009, 08:07:00 PM
Hey RCI! This is interesting. I was under same understanding as Rocket only because this subject has come up several times while speaking with race car guys. But I can't dispute your source.  Gus
Title: Boost control & rocketchip, please help me understand them....
Post by: rcicustoms on June 10, 2009, 05:13:00 PM
hey i could have been told wrong or misunderstood but all i could find says the spray pattern is determent by the injector itself... not pressure...
i also read up alot on low and high impedance..

 and the low impedance injectors are mainly used for larger applications, such as 500cc/min or higher.and for performance apps becuase of the faster responce, becuase a saturated injector takes quite a jolt of electricity to initially open it (hence the need for a resistor box ) it opens very quickly and responds quickly to changes in demand...

 high impedance use a much lower jolt to initially open the injector and only requires the power to hold that peak power level to stay open...(peak and hold) aka it dosent get as warm due to the low current, wich in turn increases longevity and reliability... and as an automaker your more concerned with longevity than responce... hence most mfgrs use a high impedance setup... where most of your higher performance models will run a low impedance for the responce of the injector...

another cool tidbit to note, is that a high impedance ecu will fry if you run a lower impedance injector....(without resistors)  an  ecu for low impedance injectors will run high impedance injectors flawlessly without mod or frying...
so essencially a dsm can run either kind without mod to anything ... all injectors are plug and play on them cool huh.....
Title: Boost control & rocketchip, please help me understand them....
Post by: Rocketman on June 10, 2009, 05:53:00 PM
Joe -

You've got your injectors mixed up a bit...low impedence are "peak & hold", high impedence are saturated type.

Low impedence have a high impulse current (peak) which slams the injector open - giving it better response - and require a lower current to hold it open (hold). These injectors require special drivers in the ECU to deal with the large peak currents. Running them in a normal saturated ECU will is possible with a resistor pack but they wont respond as fast. Running them without resistors will force an overdraw of current through the injector drivers and generally burn them up.

High impedence injectors require one single low current to open and hold them, nothing fancy. Our injectors are saturated type
Title: Boost control & rocketchip, please help me understand them....
Post by: rcicustoms on June 10, 2009, 06:37:00 PM
damnit rocket, you know what i mean ......
No, srsly. the rest of the non dislexic information is to the best of my knowledge correct....

(peak and hold)'mumbles" (saturated) "mumbles" (damnit rocket).....LOL

ok, my thinking when tuning the fuel system was this:
the ecu and pump do the same thing, no matter what valve is on the end...(injector).
so where the stockers ran lean, and the little turbo was heating air, it blew up ....
so this time, i was gonna get way more inj. than i needed.. and turn down the pressure to obviously get it to run normal on the idle ...then i could incrementally turn the boost, and fuel, up.. while watching the afr the whole time...
and as i posted in another thread (i think) im running 30 psi.(fuel) and still staying in the 12s afr all the way to redline.. with 20lbs. (out of efficientcy) boost (it crept there due to the vj-14s incredibly small wastegate hole)
the boost controller is set at 18psi with normal temp and humidity........