Is anyone making block-off plates for converting to the Weber? Need one for the fuel pump (switching to an electric one) and for the vacuum tree attached to the block on the carb side, and anything else which needs to be blocked off?
Didn't find any on eBay ... or Summit Racing, which is doing the old carb rebuilds.
Which engine? If you have the 4G52 or 4G54 I believe you can use the off-the-shelf block off plates for SBC's. If not, they're not hard to make.
1980 2.6 Liter (Sports model truck)
My "making" skills are lacking and don't want a piece of junk look, like it would be if I made one ... and one for the vacuum tree once removed.
Originally Posted by geezer101
Seriously these are one of the most basic fabbing jobs you can get into. If you can trace a gasket with a sharpie onto an off cut of alu plate, use a jigsaw, a file and a power drill you can make a half decent block off plate in an hour tops.
shedstuff103.jpg
That was made out of scrap checker plate (4G52 head but the same deal in making it)
May end up having to go that route.
First attempt ended up trash. None made at all by any vendors on the internet.
Called an automotive machine shop and they said bring in the manifold and we'll do it up right; block-off-plates for all the junk that disappears when the Weber goes on. He said all the Weber needs is one gas line in, one suction line to the valve cover vent, and one vacuum line to the distributor. Everything else gets removed and blocked off, including the big pipe to the top of the exhaust manifold!
Does this sound right? 3 lines left with the Weber?
that is right - someone that knows about how a weber works - but the plate goes on the head, not the manifold. Take him the fuel pump spacer or gasket and have a plate made to match the outline.
If it's a first attempt and this stuff is new to you don't give up. You gotta start somewhere (and anyway the first attempt is your prototype telling you where you went wrong so you can make the necessary changes to get it right)
If you delete the EGR valve on the inlet manifold it will require a block off plate. But even then that is only cosmetic really as the EGR valve will be non functioning without a vac line to actuate it.
Will omitting the ERG valve effect engine performance with the Weber?
I'm going to give it another try on the fuel pump plate.
The exhaust gas recirculation is meant to reduce NOx emissions but it also screws with your engine tune and idle. Deleting the EGR system will only improve on engine response and is an added bonus when you install a Weber. While everything is apart tidy up the inside of your inlet manifold with a flap sander drum on the end of a power drill. Give the walls of the inlet runners a buzz to smooth them out. It will aid the air/fuel charge flow.
:-) Thanks!
The exhaust gas recirculation is meant to reduce NOx emissions but it also screws with your engine tune and idle. Deleting the EGR system will only improve on engine response and is an added bonus when you install a Weber. While everything is apart tidy up the inside of your inlet manifold with a flap sander drum on the end of a power drill. Give the walls of the inlet runners a buzz to smooth them out. It will aid the air/fuel charge flow.
Oh, another thing to be weary of - E10/methanol additive fuel. If you are keen on using methanol blended fuel you will need to upsize the jetting in the Weber. I've heard of engines running like a sick dog when trying to use E10 through a Weber due to inadequate jetting. Either stick to regular or premium (you can tune the ignition for premium to make the most of it without having to alter anything else)
in the US most fuel is now E10 / ethanol blends unless you find a rare one with ethanol free gas. The jets have to go at least 1 to 2 sizes bigger to compensate for the leaning out of the mixture with the alcohol as an oxygenate. Premium fuel will not resolve this issue - you should also run an ethanol treatment such as sta-bil marine ethanol treatment, starbrite, or sta-bil 360 ethanol treatment to prevent fuel breakdown and poor running, and crud deposits on valves from the alcohol burning.
Upsize the jetting? How does one do this and where does one get the right jets? Which jets would that be for an area which only has methanol enhanced fuel?
This is getting far more complicated than first suggested to me "just swap the carb with a Weber; simple to do" ....
The Summit rebuild guaranteed for a year is a straight drop-in replacement for the stock one with the defective choke.
Before you worry about jetting, get the carb installed and running correctly. Then you can work on the jetting. You can get a jet kit here:http://www.ebay.com/itm/Redline-Jet-...-/331022115779
Keep it simple. You don't 'need' to change the jetting but if you're chasing every last bit of punch you can squeeze out of the Weber you have to do the research and jet it specifically for what you want it to do. The standard jetting will be more than adequate for a stock engine and will be an instant improvement over the Mikuni. If you want a bare bones install, disconnect the vac lines to the EGR valve, cap off any barbs on the manifold that will pose a vacuum leak once you have your distributor advance line hooked up and bolt the sucker down.
Encouraging. I hear the Weber, especially the ones with WEBER cast into it, add some performance and economy to the engine.
Keep it simple. You don't 'need' to change the jetting but if you're chasing every last bit of punch you can squeeze out of the Weber you have to do the research and jet it specifically for what you want it to do. The standard jetting will be more than adequate for a stock engine and will be an instant improvement over the Mikuni. If you want a bare bones install, disconnect the vac lines to the EGR valve, cap off any barbs on the manifold that will pose a vacuum leak once you have your distributor advance line hooked up and bolt the sucker down.
We don't want you to be scared of swapping out the carb - we just want you to have all the information to get it to the best it can be. Most of us didn't have this info when we were doing this. Didn't mean to cause info overload.
I appreciate all the advice and hints about doing the swap; thanks!!
I bought mine 10 years ago and use it for hauling. It had the Weber on it. Anyway here is a webpage that lists all the Ethanol Free gas stations in the US & Canada http://pure-gas.org/ Gas mileage is crap. I think I may have a rebuild problem in that I was told the extra gas in the intake is due to an improperly adjusted float. I put on a rebuilt head, timing belt and balancer belt when found it had one that had been broken for years. That must have been the big bang that happened a year after I bought it.Hopefully that float is the only reason why mileage sucks since even though it looks 31 years old and then some its only got 111,000ish miles on it. I posted in another thread asking if anyone knows how to adjust the float if you know please answer there.
I forgot to mention that I have the manual fuel pump with my Weber carb.
there is a weber manual on here for that adjustment. You need to run a bypass regulator if you run a mechanical pump or you will overpower the needle and seat and flood the motor with raw gas.
Putting a manual pressure regulator at 3 psi will solve the problem with an Weber using the existing fuel pump? Good to know!
I made my own with a Dremel and a drill
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