I guess my back is against the wall....

[maxrevs85]

I use the stock rad, with 180 stat Fans on at 205 off at 180...... I bought a Stewert alum pump when I did my rebuild. very good pump and not expensive.

 

[rrubel]

You've got the natural air thing going, just like me. We don't need no stinkin' AC.:L

Bah. You young'uns... when it's 95 degrees with 95% humidity and I'm stuck in bumper-to-bumper traffic, I offer SACRIFICES to the guy who invented car A/C. I NEED MY COOLTH!

Which reminds me - if all goes as planned, I'm going to replace my A/C seals this weekend and fill up with Freeze-12. My mechanic is going to drain the last of the R-12 tomorrow.

[RICHR]

 

[maxrevs85]

Its a sports car , not a LIMO......dont need no stinkin AC.....

 

[vetteboy86]

Yeah until this summer I didn't think I needed it. However in this heat has me thinking otherwise

 

[Moonunit 451]

Bah. You young'uns... when it's 95 degrees with 95% humidity and I'm stuck in bumper-to-bumper traffic, I offer SACRIFICES to the guy who invented car A/C. I NEED MY COOLTH!

Which reminds me - if all goes as planned, I'm going to replace my A/C seals this weekend and fill up with Freeze-12. My mechanic is going to drain the last of the R-12 tomorrow.

[RICHR]

A/C rules :cool Freeze12 is a direct drop in for R12 as I understand it, and does not require you to give your buddy the the free R!2 . Nothing is required

 

[rrubel]

Since I'm opening the system and replacing 19-year-old seals, I didn't want to vent any residual R-12 into the atmosphere. Mr. Green, that's me . Besides, this mechanic has done enough for me... I can spot him some Freon...
[RICHR]

 

[vetteboy86]

So that stuff can be added to the R12. How does one go about finding a leak? Can I just have the system charged with something and locate the leak? Ideally you would want something inexpensive.

 

[Edmond]

Ideally you would want something inexpensive.

Don't we all, Craig? Don't we all?:L:L:L

 

[vetteboy86]

Well I was going to go over to the builders shop tonight, and take my voice recorder. I need to get him on tape giving me the go ahead on the intake stuff I bought, which includes injectors, intake, runners, plenum, and fuel rail. What is the stock size injector, 20 or 22. I believe the injectors I bought are 24. SO if I tell him this, and the information has been discussed and caught on tape, he cant say that those parts weren't his responsibility.

What do you all think.

 

[rrubel]

I think stock injectors are 18 or 20.

Regarding the AC leak-finding, there are a couple ways. Easiest is to fill it with something inert like nitrogen at high pressure, and see if you can hear a leak. Alternately, you can use an oil (like comes with the refrigerant) and a fluorescent dye. Fill the system, start the car, turn on the AC, and use a black light to find where the dye is exiting from.

[RICHR]

 

[vetteboy86]

I rented a pressure tester, when I my intake gasket started leaking. Do they sell a tool that will do the same for the AC system. I know I have a leak, because the last time it was charged, it leaked out over night. I hate putting the refergirant in there, and waste it.

As far as injectors go, do they just flow more, or can I set that with the pressure? I assume the computer uses PWM to turn on and off the injectors, and by varying the duty cycle of the modulation can then back the amount of fuel off. THe only problem is that the computer was designed using stock injectors, so it might not be able to compensate for the added fuel.

 

[Hrtbeat1]

The computer should do alright to get it up and running. It will use the settings it knows and once it goes closed loop it will start looking at the O2, coolant temp, ect. and try and make adjustments. It may run a bit rich ... but with the other work being done it might "like" it. You can always adjust the FP with the new regulator. Of course to get the maximum out of everything you will need to dyno tune and burn a new chip.


BTW the computer thinks it has 22lb injectors. Im not sure of the actual rating of the stock injectors though.

 

[Edmond]

I'm pretty sure the stock injectors are 22 lbs. Time to look in my Probst book and see if I can find it.

 

[Edmond]

Okay, I did some quick reading and this is what I came up with on page 193 of Charles Probst's Corvette Fuel Injection book:

Installing larger capacity injectors (OEM 24 lbs/hr to 30 or 36 lbs/hr.) results in:

Plus: it is more reliable.

Minus: in L98, LT1 '92-93 there is little or no gain with a batch fire injector system (it works better with SFI, '94-01), it requires recalibration of the PROM or PCM, too big a jump may cause problems at idle or at specific points on the curves, it costs more.

From how I interpret it, the stock injectors are 24 lbs/hr.

 

[vetteboy86]

So it is very well possible that the car might be okay. I have heard in the past the rich is safe, however to rich is no good also.

 

[maxrevs85]

In most performance applications , you run a little rich. Increasing the air intake capabilities makes for more fuel needs. On initial start, open loop , it will run rich, like a choke on a carburated car. After it goes to closed loop, you will tune it. I use a heated O2 . It goes to closed loop quicker. Bigger injectors increase the capability to privide fuel. A 24lb injector is not big. Stock are 20 to 22lb. At some point Craig you will need a prom burned. Make sure you keep record of all your engine specs, cam ,heads,engine bore,etc....

 

[vetteboy86]

Oh yes, I will keep good documentation. I was worried about the computer thinking it was controlling a 22 lb injector instead of the 24. Just what exactly is the difference?

Will the car run okay with the hypertech prom in it now. I hope I do not have to have it tuned right away. At least get it broke in.

 

[rrubel]

The car should run decently. I've got the equivalent of a Hypertech "stock" chip in mine right now (different brand) and it runs "ok". Rich, and failed emissions, but I'm driving it... Ran a 13.71 @ 106 mph at the strip, too, with that chip on the new motor.
[RICHR]

 

[vetteboy86]

Well the more I think about it, the car might be okay. WIth the more cubes, and the increase in air flow, it is possible for the computer to regulate the fuel. The engine builder said it should be no problem. Once it goes, he has some kind of scan tool that will monitor the O2 sensor. He will adjust the fuel pressure to a base line of what he thinks it should be.

Oh by the way, he said my motor should be together a week from today.

 

[rrubel]

Well, you won't know how it's *really* running until you put a scanner on it. When it's fully broken-in, let me know. Hopefully I'll be done with my laptop/scanner by then and I can loan it to you. You're in South Bend; you can ship it to my Dad when you're done - he's in southern Indiana. Anyway, take some readings from idle to WOT and post them here and someone should be able to explain if they're OK or you still need tweaking. Heck, by then maybe I'll even be able to understand the numbers.
[RICHR]