[Megs]

I currently have been thinking about a set of CTR pistons and stronger rods in my 94 gsr. I have I/H/E and not much else. Its a daily driver but not much more than 20 miles a day and looking to do mid to low 13's. What I was wondering is that if i use standard bore CTR pistons on a b18c1 and yeild like 12:1 compression with the stock head gasket. Would a vafc be able to handle the tuning necessary to run off of pump gas. ( I have access to 93 and 94 octane down the road, also 101 octane if absolutly needed about 10 miles away..)

I also realize that the stock cams would be severly undercammed so i was thinking of Toda B Specs but i want to keep it street friendly. so and my second question is are toda B going a bit to much or would they work well with that static CR?

Duration (lift mm)
SPEC B IN 250 (11.0) - 295 (12.0) - 250 (11.0)
EX 250 (11.0) - 285 (12.0) - 250 (11.0)

 

[MichaelDelaney]

those cam specs are advertised durations (duration at a valve lift just barely off the valve seat) from the Toda website. it's not the specs you use when you compare between cams when you shop. We have the 1mm lift durations (the import standard) in the VTEC cam specs article here.

secondly, you can't use your stock GSR ECU with Toda B's since they need to rev to 8800-9300 rpm. So although you can "get by" with a VAFC, it won't take you all the way. Those cams and the 12.3:1 CR with the CTR pistons in your GSR will need bigger injectors and a fuel pump move up.

 

[MichaelDelaney]

ok reprogrammed ecu 420 cc injectoers stock headgasket is a no one something a little thinker and metal. the apexi will handle ur needs fine. it will work on 93-94 and 101 gas. it will even work on 87. the only reason people use higher octane is because of all the water in the low octane but octane boost will fix it. u mainly need a high octane for a turbo/supercharger engine cuz ir gettin high output nad ur engine is tryign to scavange for fuel for the fire. so around 400cc injectors, remapped ecu, go with type r cams those will work great or civic type r cams, new cam gears adjustable gears will work great. get an external fuel pump that way if somehting happens its easy to fix unlike intank pumps. it might cast more now but will save in the long run. skunk 2 cams work great there are many appps avalible but remember with a longer duration of opening its less streetable it wont pass inspection and hard to drive on the road cuz of hte high idle range. wiht a fuel pump u cna go wiht a nos fuel pump those work well stay away from aem ur paying for name mostly and a venom/python pump will work.

can anyone tell me what he just said?

there's no such thing as 420 cc/min injectors in high impedance saturated type injectors which is what we use. Toyota pintles and RC (Lucas) disc jets are 440 cc/min. If you want to go to low impedance peak & hold, the sizing is 450 cc/min from the DSM injectors.

You don't need 440 or 450 injectors to run Toda B's. 310-370 cc/min saturateds are fine but the 370's force you to reprogram and recalibrate the ECU.

Bottomline, a VAFC and stock ECU is only a "get by" setup and not the proper set up with a 12:1+ CR Toda B package.

 

[mike5809]

I agree a AFC will get u buy and do the job;

But bigger inj/ fuel rail/ fpr will be what u would want for best tuning and to run the best. Maybe a fuel pump...and hondata would be better then an afc. But the afc would get the car to run good...I might also get a chipped ecu with some remapped fuel and timing...

And the car will pass inspection. Esp in PA i got a set of huge Crower cams in my LS and it passes...but PA is pretty leaniant on inspections but they are cracking down now.

 

[MichaelDelaney]

if you upgrade the injectors, it would be wise to recalibrate the ECU program's fuel tables for those injectors instead of making it think that it's still controlling 240 cc/min stock injectors. Otherwise you'll over fuel and run way too rich (killing your cat and washing your cylinder walls down with fuel and preventing a good piston ring seal...or compression).

many people don't understand when they need to upgrade the fuel pump. you only need a fuel pump if the fp is so high that it prevents enough fuel from reaching rail or the stock pump doesn't provide the minimum mass flow rate for your injectors. for the i/h/c/e crowd, an ITR /GSR/Civic Si fuel pump is plenty. It's only when you get up to 11.6-12.5:1 CR (or more) N/A OR FI that you begin to consider the fuel pump change.

 

[Megs]

thanks for the multiple replies it answers just about all i need to know and then some.

I already have a bigger aftermarket fuel pump that I got from a friend. I was wondering if a vafc would get me by because i dont know of a place that can fuel tune or even a dyno that is in the pittsburgh area. Is there any decent places I could send my ecu with a list of mods and they tune it at least in the ball park?

 

[MichaelDelaney]

many years ago, before hondata and aem ems came out, most people used the vafc only and settled for that plus a mail order best guess chip with a 9000 redline. the B's need the redline bumped up. the vafc can't do that.

also the max. VTEC switchover on the vafc is 7000 rpm...the toda b's sometimes need a 7300-7500 rpm switchover.

some people go the other way and run mostly on the VTEC lobe (switchover 3000-3500 rpm) especially with the right exhaust system but you need a reprogram with that to severely lean things down.

 

[BlueTeg]

I was wondering if a vafc would get me by because i dont know of a place that can fuel tune or even a dyno that is in the pittsburgh area.

If theres no way that you have access to a dyno to accurately fuel tune you might want to reconsider getting the VAFC. I can't think of any other way to accurately (and more imporatantly: safely) tune it for your setup.

My advice would be that if you're serious about modding your car (and it sounds like you are) to sack up and make the trip to the nearest dyno facility w/ oxygen sampling capability. You don't want to spend all this money on mods and short change yourself on the fuel tuning.

 

[Megs]

again thanks for the good and quick replys.
but I didnt say there is no way..i just dont know of any dyno that can sample oxygen around here, if its a 2-3 hour trip to ohio, NY, or to va thats no big deal, i just need the car to run till i get there

. We have one at school i could use but I dont think I would trust myself alone to fuel tuning my baby.

MD werent you running a similar setup? hows it been treating you? were you satisfied with the power gain?