Alfa Romeo Forums banner
1 - 8 of 8 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter · #1 · (Edited)
So i have the engine out of my 89l-jet spider at moment, and have a new one on the way, but its twin carby. so options are to put it in as is, or try fit the injection to the old head, but i know that the injection manifold wont bolt straight on. Keeping in mind that we don't have any sort of emissions issues here in Australia, can anybody suggest why in the interim i couldnt just throw in the engine with the twins and, put in a fuel pressure reg and be on my way? Also of note is my distaste for the archaic l-jet injection system, but that may well get upgraded to megasquirt later on. Right now the aim is just to get the car back on the road. Im told that the new engine came from a gtv. I should set eyes on in early next week. Might be worth adding that i have some much larger than stock cams going at some point, i dont expect the l-jet system to take to kindly to that.

Thoughts / comments appreciated.
 

·
Registered
Joined
·
520 Posts
The L-Jet manifold does bolt straight up, but it mucks up your injector spray pattern. To fix that you just need to file a relief into the top of the inlet port's face, nothing major.

If you were going to switch to carbs, I'd replace the fuel pump with a low pressure one.
The original pump's pressure is way too high, and I don't know if a regulator (or the pump) will like having to reduce 40 psi down to 4...
And don't forget the fuel return line, it's not used with carbs.
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #3 ·
In regard to the fuel pump, i have two ideas in mind. 1) run a surge tank then low pressure fuel pump to carb 2) just use the lift pump in tank and get rid of the hi pressure. Also i had to modify stud holes in a dcoe manifold to fit onto a l-jet head, so surely i would have to do the same to make the l-jet manifold fit onto the carb head?
 

·
Registered
Joined
·
520 Posts
I'd go with just a low pressure lift pump, to save heating up the circulated fuel (and it's simpler).

What stud holes did you have to modify? I'm running an '85 Spider L-Jet inlet manifold on my '77 Alfetta and all I did was the port relief notches for the injectors.
From memory one of the carb head's studs was a bit long, so I used a ~8mm thick spacer under the nut on that stud.
I suppose going the other way, that stud would be too short - but the stud pattern lined up fine.
But apart from that, it was a straight swap.
The L-Jet inlet gasket is needed, and the coolant hoses needed modification (thermostat is in a different position) so beware that your spider hoses probably won't fit.
I'm not sure if your throttle linkage will be a straight swap either - I swapped to a cable operated throttle body so didn't have to cross that bridge...
 
1 - 8 of 8 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top