When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
First this is a great forum, I have been a member for several months but only posted once way back. The amount of good information and knowledgeable people is almost beond belief.
I would like to know what type of baffles should be in the fuel tank on my 82. I have had it for years now and it has always dropped fuel pressure when the tank is below 3/8ths or so and a hard right turn such as a intersection. The fuel pump and sock has been replaced one time and had no effect. The engine will drop out and then pick back up when it comes out of the turn. More fuel in the tank than that and it never happens.
Any other suggestions would be very much appreciated.
There was a few post here about a week ago that said there was no baffles in the 82.They said the 78 to the 82 was the same tank.I try to find it and get the link.
If it were me I would get some of the foam that comes in a racing fuel cell remove the gas cap inlet and stuff it in your tank at both ends-make sure it doesnt interfere with the fuel float for the gauge.
Oh and you can do it from the top of the car-just be very careful not to scratch the paint.
Have you replaced the small black coupling from the pump to the line? ..they are bad to swell and you will lose pressure when the fuel level is below the coupling. While you have the pump out change over to an 85 TPI fuel pump as it has much better volume did mine this summer. Better start-ups and smother idle and throttle response.
Thanks for the link DWncchs, that answers my question about the baffles. Sounds like I may want to get an eariler tank when the time comes. By the way the pressure drop did come in handy one time when the gas guage stopped working. When the stall happened it meant I had about 1/4 tank left and time to get gas. Thanks again.
There are no baffles in that tank! I have coverted my 81 to TPI using a stock 82 sending unit, when the tank runs low the fuel sloshs all over! Newer cars the fuel pump sits in a litte can that return line dumps into keeping the pump in fuel all the time. Just keep the tank above 1/2. Also DONT!! replace your pump with one from a 85 they are different 82 crossfire is a low pressure system! 85 is a high pressure system.
I guess you could use the 85 pump, as you are correct about the pressure regulator setting the correct pressure. But thats about 25lbs comming back on the return line. I wonder if return line could handle the extra presure if the reg. failed? I know on my 81 the return line was 1/4 and was not set up to return pressure but It did not come stock with fuel Inj. Just a thuoght?
I guess you could use the 85 pump, as you are correct about the pressure regulator setting the correct pressure. But thats about 25lbs comming back on the return line. I wonder if return line could handle the extra presure if the reg. failed? I know on my 81 the return line was 1/4 and was not set up to return pressure but It did not come stock with fuel Inj. Just a thuoght?
The small return line does fine on my TPI conversion with an external pump comparable to the 85 pump. Never had any issues, pressure is within specs. I keep over 1/4 tank of fuel and have not had sloshing issues with the stock tank either.
There are no baffels in an 82 tank.I had the same problem(as will all cfi ),the 82 pump doesn't maintain a constant fuel pressure of 9 lbs.,12 lbs. is what I like ,some like more,some like less (9-13). An 85 pump will be the best thing you could do IMHO.Do check out http://www.crossfire.homeip.net/ you will get alot of help with general tuning of the cfi system.Corvette Fourm Rocks
I don't see how you would position or attach the foam in the tank so it wouldn't bump up against the pickup and level. Seems like the foam would move around when cornering when the tank is a little fuller than the foam blocks are tall.
jdp6000, I can certainly pull the pump and sending unit back out and check the sock but when I pulled and replace the pump about a year ago it looked ok as did the new one I put in.
Does anyone know what the clearance between the sock and the bottom of the tank should be? One thought was something had been changed before I bought the car and this is causing the problem.
I don't see how you would position or attach the foam in the tank so it wouldn't bump up against the pickup and level. Seems like the foam would move around when cornering when the tank is a little fuller than the foam blocks are tall.
I think if on the left side of the tank you stacked foam from top to bottom and came over within a few inches of the pump it would be OK.The foam does get heavy when wet.I had to install a gauge in a fuel cell and had to remove all the foam.Thats how they had it held in place was to just stuff it in and wedge it top and bottom.I would think by doing half the tank it would reduce the sloshing a bunch.
Thanks DWncchs, that is an option and I will keep it in mind. After a few years with this vette I find I really like the somewhat slower but very curvey roads and turns. The car handles better the lower it is on gas so it is a pain sometimes keeping just enough gas in it to really get into the turns but not drop pressure. There is some great 2 lane but seldom traveled roads in north GA.
jdp6000, I can certainly pull the pump and sending unit back out and check the sock but when I pulled and replace the pump about a year ago it looked ok as did the new one I put in.
Does anyone know what the clearance between the sock and the bottom of the tank should be? One thought was something had been changed before I bought the car and this is causing the problem.
Corvette forum does rock!!
Manual says to check fuel filter. Check fuel lines for pinching..
I don't think you can adjust the sock height...it attaches to the pump which attaches to the assemble.
Manual also says there is a plastic liner in the tank...could it have warped???
FYI: the '82 fuel tank has a polyurethane liner. The earlier tanks have a rubber liner. The rubber liner tends to separate from the metal tank and cause fuel level/pickup problems. Because it was the last year for the C3 model, GM installed some new, unproven pieces in it to minimize the risk of getting a bad reputation for the new C4 model. Among them was the 700R4 transmission, magnesium valve covers, crossfire injection, and the polyurethane lined fuel tank.
jdp6000, as I remember there is a rubber hose about 4 inches long from the steel line to the pump itself. The one that came with the new pump was the same size as the old one but I thought perhaps both might have been a bit short.
The filter gets changed every tune up but the pinched lines is sure something I can check.
I will try some of these suggestions and see what happens. Perhaps this will help someone else with a simular problem.