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Tech QuestionsMarch 2002 Tech Q & A

Answer by Technical Editor Rex Chalmers


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March Topics:

Red Line Oils & L-Jet Performance Mods | Injector Cleaners | Dellorto Carb Set-Up
2 Liter Crankshaft Pulleys | Alfetta Rear Rotor Removal

Redline Oils & L-jet Spider Performace Mods : question by Gabriel Forzano | ’86 Spider

1. I'd like feedback concerning Redline lubricants. I’m having my transmission rebuilt next week, wondering if using Redline's 75W90NS will give me better shifting and longer second gear life?

Also my engine has 62K miles and ticks a bit, but runs strong, will using their 20W50 Synthetic Oil help, and lead to longer life? Will it cause engine leaks? I've heard this is sometimes the case with synthetic oils in older engines. This oil uses no polymeric thickeners as used in multi grade petro oils.

2. Engine Mods - I've heard my L-Jet FI makes it difficult to modify this engine and have it continue to run smoothly? I'm not considering race type mods, but a lite cam, minor headwork, and an electronic ignition like RML Optical Triggered unit. Are these items worth the investment?
I'm just looking for a better responsive engine. I've read the specs on Euro engine with Approx. 30 more HP, with very few mods..I don't want to install 10:1 pistons (right now at least) I'll wait till I need the lower end done.
Answer : Yes, Redline’s 75W90NS will work quite nicely in your Alfa’s gearbox. Be sure to get the NS grade oil. The other 75W90 synthetic that Redline manufactures is too slippery for the Porsche style synchros that Alfa uses. In general, most synthetic gear oils are not suitable for Alfa gearboxes because they are so slippery that they don’t provide enough friction between the selector and the synchro ring to allow the synchro mechanism to slow the gear down enough to allow proper engagement of the synchro teeth. Consequently we have the annoying and expensive characteristic “grinding” and wearing down of the engagement teeth on the gear, the synchro and selector rings.

Your concern over the use of synthetic oil in your Alfa is not uncommon. When synthetic oils first came out there were problems with leakage at the gaskets and seals. Most of the synthetic oils available today have changed their formulas to alleviate the problems associated with leakage and oil burning. I have been using
Mobil One 15W50 in street and race Alfa’s for many years with great success and never hesitate to recommend it to anyone who will listen.

The problem with modifying your L-jet engine is that the fuel injection and ignition electronic control units are not easily modified to deal with the increased rpm, fuel and air flow that you need to get more performance. If you want more performance from your engine, the first thing I would do is purchase a modified E.C.U. from one of the Alfa parts vendors and you might consider installing
the
RML ignition unit. If that doesn’t give you the performance gain that you are looking for, try a set of high performance street cams. If you still want more, have the head ported and install big intake valves. I wouldn’t go for the big exhaust valves judging from what you say you want from your engine. While you have the head off, pull the pan and install the 10:1 CR pistons. I wouldn’t do any more than that unless you are willing to install programmable fuel injection or Weber carburetors. Good luck and let us know what you end up doing and what results you achieved.

Injector Cleaners : question by Garfield Lee | 87 Milano

I often come across articles that recommend use of off-the-shelf injector cleaner and fuel system cleaner, i.e. Lubro-Moly, Kleenflo, etc. on a regular basis. Is this really necessary? I have also read that some of these products are recommended by Bosch but do they really help? A friend of mine thinks the only effective way to clean the injectors is to have them done professionally and these additives don't really do much.
Answer : I have been recommending the use of Fuel injector cleaners for many years and have had good success with the Lubro-Moly, Chevron, Ford, and Volkswagon branded cleaners. I am certain that there are other good cleaners out there but these are the ones that I have had success with. Generally, I would say that using the cleaner twice a year would be sufficient for most drivers. Sometimes no amount of injector cleaner will clean out a badly clogged up injector. Taking out the injectors and having them professionally prepared is absolutely the only way to clean these problem injectors. Another issue that many folks are not aware of is that the flow rate of injectors often varies from injector to injector. I stock several sets of match flowed and cleaned injectors for my customers. Installing a set of flow matched injectors can solve many driveability problems including rough idle, surge and hesitation. You can have the cleanest injectors in the universe, but if the flow varies much more than a few percent from injector to injector, you could have running problems that no amount of tuning will cure.

Dellorto Carb Set-Up : question by Shane Murphy | 77 Spider

I have purchased (used)a pair of 40 Dellortos, an euro intake and airbox. How well will this run ,just for street, if I install this in my Alfa with the stock Spica cams? What problems could I expect?

Answer : Assuming that the Dellortos are not in need of reconditioning and that you have the proper carb linkage parts, you should not expect any running problems. I would make sure that they are jetted correctly for your 2.0 engine. The standard 2.0 euro spec jetting would be a good place to start. The standard Dellorto carb for your engine is a DHLA40.

The standard 2.0. jetting is:

Air choke 32mm.
Main jet 135
Air correction jet 200
Choke jet 50
Accelerator pump jet 33
Float needle 1.5
Float weight 10 gr.

As always make certain that the carbs are synchronized, that the idle screws are balanced properly for each cylinder, and be sure to check for full butterfly opening when you finish with the installation. I would suggest that you latch on to a set of euro 2 liter cams, they are a very nice street grind that will give you good low end, mid range and will not die at 5500 RPM as the Spica cams do.

Dellorto Carb Set-Up : question by Shane Murphy | 77 Spider

I have purchased (used)a pair of 40 Dellortos, an euro intake and airbox. How well will this run ,just for street, if I install this in my Alfa with the stock Spica cams? What problems could I expect?

Answer : I believe that you may be correct as to the reasons that Alfa put that pulley on Alfettas. Lord knows that the transaxle cars, as wonderful of machines as they are, did have driveline vibration issues. Personally, I don’t much care for the dampened pulley for several reasons. First of all, the dampened pulleys are prone to separation, the results of this failure can be catastrophic for the radiator, not to mention stranding you on some stretch of lonely deserted highway. Also, you are probably better off with a smaller pulley as it will slow down the alternator and water pump and is a much smaller and lighter mass. That being said, there is no good reason why you can’t use the dampened pulley if you are so inclined. I would, however check to see if it will clear the chassis of the '64 Spider.

Alfetta Rear Rotor Removal : question by Shawn Franko | ’79 Alfetta Sport Sedan

I'm trying to swap rear brake calipers and disc from a '76 Alfetta GT to a '79 Sport Sedan. So far I am unable to remove the left (driver's side) rotor from the GT donor transaxle. I've tried penetrating oil and heat from a propane torch to no avail. Tight fitting wrenches or vise grips are rounding off the bolt heads and not budging the bolts. Oddly enough, the right side came off with very little effort and was some what corroded with surface rust which the difficult side is not.

Is there a better method? Are these nuts reverse treaded?

Answer : Rest assured that you are not the first Alfisti to ever to run into this problem. The bolts are not left hand thread. A good method to remove these bolts, if the heads are already rounded off, is to use a carbide cutoff wheel on a die grinder or a hacksaw to cut the heads off flush with the disc mounting surface. I normally use a 6 point box end wrench to loosen these bolts. If you do have to cut off the heads, the bolt shafts are usually very loose after the head is cut off , if they weren’t rusted or corroded, as all that was really holding them in was bolt stretch. Once you remove the head the tension on the threads was released thus the remaining bolt shaft will generally be loose. If you can’t remove the bolt shaft at this point, the brake disc can generally be removed by taking out the brake pads and by completely retracting the inner piston. At this point the bolt shaft can usually be backed out with a pair of channel locks or a pair of vise grips. I don’t think that you should have too much trouble as I have yet to run into a seized rear brake disc bolt on a 4 or 6 cyl. transaxle Alfa that I couldn’t persuade out of the halfshaft flange. Good Luck!

Heater Valve Replacement : question by Kirk Schroede | ’86 Spider Veloce

Not a big one - except it's cold here in Seattle. I'm having problems with heating. I think it must be the heater valve. I can run water through the heater core, but only at very high pressure. The valve shuts off the water and controls the water flow but again only at high pressure. The water runs clear. I also checked with compressed air and found that air would flow in the proper direction but no flow if I sent it the other way, Please tell me I don't have to remove the dash etc. to fix this problem.

Kirk Schroede| ’86 Spider Veloce
Answer : Nice diagnosis. I believe that you have properly diagnosed a bad heater valve. No, you don’t have to extract the dash to change the heater valve. You may have some chiropractor bills by the time you are done, but the dash stays where Alfa put it.

Once you have replaced the heater valve, I would refrain from usage of high pressure water or air in the system to check the valve. With the heater valve set to full heat, remove the upper and lower heater hoses from the water pump and manifold. Then, you may introduce water at low pressure, your system runs at around 10-12 psi, into the upper hose, it should flow freely out the lower hose. While you have the coolant out of the engine, it’s a good idea to flush the block and radiator with fresh water. When re-filling the system, be sure to use distilled water, 50% anti-freeze and a good corrosion inhibitor. Be sure to open the bleeder on top of the intake manifold and leave the heater valve open when filling and bleeding the system. Now, enjoy a nice warm ride to your nearest Starbucks.

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