I’ve read many post here on G2IC.com about the Gude head package on an LS, but nothing about it on a GSR. It might be old news to some of you but I just had some questions about it and those of you that have experienced the head package, please speak up and let me know of your feedback.
I have a 92 GSR and I’m currently having a local shop rebuild the motor and put on a Gude Head Package I bought from someone. The head package is for a Del Sol VTEC and i got it for $950. Thats pretty cheap since I didnt have to send back my old stuff for the core charge through the company www.gude.com What do you think of my set up and will it work w/ 91 pump gas since many of you said the head has a higher compression and rough idle. This package I got came w/ the ECU also though so will further fine tuning be needed still or will it still idle hard. Heres what I’ll be currently running:
Gude Head Package w/ ECU
PCT pistons (CTR)
Cometic head gasket
ACL Race mains,rods, and thrust bearing
ITR oil pump
New OEM timing belt tensioner
New OEM water pump
ARP head studs
GReddy timing belt
Unorthodox SS Pulley set
310cc RC injectors
Walbro 255lph pump
Ebay FPR
XTD Stage 3 clutch w/ 8lb flywheel
Gates alt,p/s,a/c belts
AEM cam gears (zero’d out )
I will be getting my car back within the next week and I hope nothing goes wrong. Im assuming the ECU will take care of any idling problems but i could be wrong. Please let me know what you guys think. VERY MUCH APPRECIATE IT.
it should be meant for stock injectors so it will need quite a bit of tuning. from what i understand they bring the head to the limits, they raise the compression as much as really possible with just changing the head. i would be seriously worried about valves hitting pistons. make sure to clay the motor before you run it. cams i dont think are anything too crazy, im pretty sure the package is meant to be for the street.
if you install the stock injectors it would probably run pretty well.
I’ve emailed to GUDE and Bill Gude himself replied that my set up will work with the PCT pistons. I shouldn’t have to worry about any valve slap. but the only thing i have to worry about the vacuum lines; its going to be a mess. I got diff injectors because my old ones were crap, fuel injector cleaner barely helped, so figured to upgrade to take care of any future tuning. Even w/the higher 310cc injectors shouldnt the ecu take care of how much fuel to dump reguardless of how big the orfices are on the injectors? If the ecu is programed to dump lets say 200cc worth of fuel at a specific RPM, it’ll only do 200cc reguardless of the 310cc injectors shouldnt it? Also the shop didnt install my adjustable FPR, he’s keeping the stock FPR on for liability purposes so im worried that it’ll dump too much fuel, not letting enough to go back to the tank. I guess i’ll hurry up once i get the car back and hook up the FPR my self. Im guessing once i hook up the adj. FPR, i’ll have to set it back to normal 38psi since the “head package” is set up for a stock setup.
no if the the injectors use pulses, the ecu has no idea what size injectors you’re running. it will be injecting 20% more fuel than it should be. also, i wouldn’t trust the ebay fpr. i would have it tuned when you get a chance too.
Thanks for all of your input. I just got off the phone w/ BILL GUDE himself and he wanted to warn me and all others about running PCT pistons w/ their head packages. It’ll work just fine w/ no valve slap but combining the two, you will have at least 12.5:1 to 13:1 C/R. He recommends AT LEAST 92 octane but preferably 93.
I think the 310cc will be fine for my setup even though the head package is designed for a close to stock build up. My setup will be in the 200hp+ range so I’ve done some research and heres what I came up with:
Selecting the Proper Injector
In order to select the correct size injector for your application, you might wish to use one of the following formulas.
In most cases a naturally aspirated engine will have a B.S.F.C of .50. This means that the engine will use .50 lbs. of fuel per hour for each horsepower it produces. Turbocharged engines will want to be at .60 lbs. per hour or higher.
Using these numbers as a guideline, you can select the approximate injector size in the following formula for a four cylinder, naturally aspirated engine at 200 bhp.
Most injectors will max out at 80% duty cycle and this is the accepted industry standard.
B.S.F.C is brake specific fuel consumption - How much fuel you are using per horsepower per hour
HP X B.S.F.C. divided by #injectors X .80 = 200 X .50 divided by 3.2 =
31.25lbs/hr per injector
Convert to cc/min: 31.2 X 10.50 328cc/min
The proper injector for this application would be 31 lbs. / hr. or 330 cc / min
You see, even at 200hp target it’s required that 330 cc injectors and mine are 310cc so I think I’ll be ok
Source of info provided by: RC Engineering www.rceng.com
i didn’t say you chose the wrong injector, i said the ecu won’t be setup for your larger injectors. either run stock injectors with the gude ecu(prolly dangerous), or have your car tuned. running larger injectors on an ecu setup for stock injectors will have you running rich.