Bosch Mechanical Injection Settings...

I am going to give Pacific Fuel Injection a call today to try and obtain a copy of the "MFI Blue Book" that most people recommend. For now though, could anyone offer me stack airflow settings and CO settings for a 2.7 RS motor? I am going to order a synchrometer and the MFI toolset today, so I will probably receive the tools before the book. Also, is the suggested idle rpm between 850 - 950 rpm? My idle speed is currently around 600 rpm. I need to get to work on making the necessary adjustments! Thanks.

Bill

------------------
William Armentrout
1973 911T
2.7 carerra rs specs
www.geocities.com/william_armentrout

The "Blue book" is silent on the RS. To adjust the 2.4 stacks screw all air correction screws in then open all 3 half turns. Run engine at 3000 RPM's measure flow of all six. Take the average of all six, adjust each stack to that measurement. If you have to open any one screw more than 8 half turns that one is clogged and should be cleaned.

There are two CO adjustments part load and idle. Part load for the 2.4S is 2.0-2.5%Idle measurement is 2.5%+- .5% for all engines so this may be true for th 2.7. Always do the part load first.

The idle speed for all these engines covered is 900+-50 RPM's, this is probably true for you.

There is a procedure for the part load throttle valve angle 9 degrees engine RPM 2,400 car in 2nd gear and use the brake to load the car down to the correct RPM of 2,400. They also list corrections for doing this on the dyno VS on the road.

Again this is all for the 2.4 "S" you may want to find out if these numbers are the same for the RS. They may be as I believe the cam is the same, just a little more displacement. Although the space cam is diferent, I don't know. At the least it appears your idle is a little low. Sounds like you have a nice car though. Do you have any pictures?

Mackgoo,

Thanks for the help. I should be receiving my synchrometer and bosch tools within the next 2 days. I definately need to adjust the idle. I was referred to Gus Pfister for obtaining the Bosch reference manual, but was unable to get in contact with him yet.

My car is a "work in progress". I have put a lot of money in it so far, but I am far from satisfied. I guess my next big step is to get a quality paint job. The paint that is on it now looks good from a distance, but you can tell that the paint job was performed by an amateur. Anyway, check out www.geocities.com/william_armentrout for my web page. I have a long list of modifications, along with some rebuild pictures. You might find it interesting. I plan on adding some 911 history information in the future, but I have not been spending a lot of time on the page lately.

Bill

------------------
William Armentrout
1973 911T
2.7 carerra rs specs
www.geocities.com/william_armentrout

Looks good. I'm interested in your engine as I am doing the same thing for a different aplication. Are the specs your dyno run? How is the engine set up exhaust etc.? What were you running for filtration.

Mackgoo,

Yes, the dyno specs are for my engine. The date is incorrect though. I have a new single tip exhaust on my car(the old one was full of oil from the pre-rebuilt motor and made the car smoke). It looks stock, by I believe that it is a "sport" muffler with a chrome tip. I really wanted a "sport" dual tip muffler, but G&W Motorwerks could not obtain one at the time of my rebuild. As far as filtration goes, G&W probably removed the air filter at the time of the dyno run. I plan on purchasing a K&N in the near future. Right now, I have a stock air filter.

I would recommend G&W Motorwerks in Waynesboro, VA. They can give you a price list for a rebuild/conversion of your engine if you would like it. Take a look at http://www.gandw.com/

Bill

------------------
William Armentrout
1973 911T
2.7 carerra rs specs
www.geocities.com/william_armentrout

While we're on this MFI thread, I have a couple of questions which would be great to resolve:

I went to set the correlation between the injection lever and throttle bodies, and was in the process of making up suitable protractors in the absence of the factory tools....then I began to wonder if it was actually necessary to measure these at all. My reasoning is that there seems little you can do if it's actually off by any great degree. Please feel free to correct me -I WANT to know otherwise-.
The blue book< Mackgoo > explains to be sure that all levers are resting on their stop positions before measurements are made. I assume the ideal is to have this situation AND have the degrees between everything correlated properly. To make adjustments, the book says to set the 'basic adjustment' of the injection rod (14.2 +/- 0.2mm)and then recheck the two throttle rods, altering their length to eliminate binding or mismatch on the balls- as long as the two rods are within 5mm total length of each other. And, I presume, to let them both lay on their stops at zero throttle. Then to recheck the protractors.

Still following? If I'm correct, the correlation (in degrees) should be correct by default, for where else can you make adjustment?

All this assumes that the butterflies are synchronised with each other. The book doesn't say how this is done (apart from the air bleed screws) but I'm guessing you need to strip the lot apart and set it up on the bench with a dial gauge on the buterflies or similar and then get the individual throttle rods doing the same thing in unison. That's the only way I can see to make the throttle stop positions make any sense with regard to the setting up procedure if they are out. I suppose you have to assume they are ok, but this seems doubtful in a 28 year old car.
I'll clarify all that if it made no sense. Basically I think you need more info to set the lot up accurately. Is this in the factory workshop manuals?

Second question: My stop solenoid has an intermittant fault which I traced to the solenoid itself. I'll be able to get it going (hoping....) but I wonder why the Blue book, and Haynes manuals are so anti removing this part, suggesting a Bosch service agent should do it. I had it out last nite- extremely easy- and was examining it on the bench. It's all logical and straightfoward. All you get is a big puddle of oil from the pump everywhere. I appreciate the rod needs to be set accurately if a new one is needed, but hey, give us a break! It's not beyond the scope of someone familiar with a flat bladed screwdriver.

Answers anyone (Mackgoo?)

------------------
'72 911 TE

Bill, I must say your car looks exceptionally great! This may be a little biased because I happen own its complementary sister in Targa form, complete with matching stainless hoop. Everything else is the same though: Same slightly faded silver paint, same spoiler (except I have a single optional(??) chrome bar between the two rear bumber irons), exactly the same Fuchs, interior and headlight rims. I think we have the 's' trim pack. Does yours have sway bars fitted- and Konis? I'm undecided if they were factory on the T's or not. I have them.

The PO fitted a beautifully crafted single exit stainless sports muffler, which sounds awesome and looks good slung down there. I replaced the air filter with a K&N because I like them and they're good. Next step? Full 2.7 RS specs.....haw haw haw!
Seriously I would love to do that, but I fear over capitalising the car. Would you say it's been worth it?

Koni's and anti-roll bars were not standard on the T's, but they were optional, so whoever ordered your car did the 'right' thing on the order blank!

------------------
Warren Hall
1973 911S Targa

I suspected as much Warren. Due to being an originality nutter I'm going to have to remove them unfortunately.

Seems I inherited a car from someone who liked all the bits except the quick engine. It was 'born' in Salt Lake City- I have all the original invoices and tax/insurance receipts. Not having ever been here,my mental image is of a large flat place with not many corners (wrong totally?), so I wonder what the use was of having a car that handles well in this situation. The guy was probably some rich poser who if he were to repeat his purchase today would be on the waiting list for a new 996!

Matt,

It sounds like you wish to synchronize the butterfly valves on your throttle bodies. Prior to a rebuild/rebore of my throttle bodies, I took the black stacks off of my car to do the same thing. My butterflies were really out of whack...I think the previous owner may have tried to set them by adjusting the length of the arms without being able to see each valve. Basically, my conclusion was that you can set the butterflies using only your eye, provided that the stacks have been removed to allow visual inspection. This task is relatively easy, it just takes time to remove each rod, adjust it's length, and snap it back on. I personally don't see how these rods could get messed up, unless someone misadjusted them in the past, or someone removed the stacks and somehow got the right valves out of synch with the left side when re-installing the stacks.

I don't have any suggestions for your second question.

Thanks for the compliment on my car. I would have liked to purchase a targa instead, but I feel that I got a good deal on the car($4400). All other 911's that I saw were in the 8-10k range. My car was in desperate need of a lot of attention, but the body is real solid. I really need to get my CO level measured, stack airflow adjusted, and MFI rack adjusted to get the car where I want it to be. My 911 really moves. It will easily spin through first and snap second gear. I don't do this often, but it is fun.

I think I do have an "S" trim pack too. The guy at G&W mentioned that my front bumper was an "S" bumper. As far as shocks go, mine are currently green in color. Isn't that Boge shocks? Or Bilstein? They may have been replaced in the past, but I plan on replacing them soon. Any recommendations? I haven't noticed any sway bars on my car. I too am going to get a K&N air filter. They rule. I have one on my 97 Z24(cold air intake). It is nice to be able to clean them and hose them off.

As far as the 2.7RS conversion is concerned...I love it. The 223hp is a big step forward from <140hp. I haven't really been able to enjoy the rebuild yet though, because of the "jerking" that my car exhibits after warming up. Hopefully, I can make the adjustments myself. Thanks for your comments.

Bill

------------------
William Armentrout
1973 911T
2.7 carerra rs specs
www.geocities.com/william_armentrout

Matt, just had to reply....

Salt Lake City is a place made for Porsches.

To the west, long straight deserted roads for getting that high speed adrenaline rush.

But, more importantly, to the EAST, Salt Lake City is surrounded by beautiful mountains (AND mountain roads). The Park City ski resort is just 30 minutes up the hill. Just past all the Park City stuff are miles and miles of gorgeous mountain valley roads that your car must have eaten up.

Highway 40 east out of Park City is particularly Porshce friendly -- what a drive. 175 miles or so or twisty undulating mountain and valley roads all the way to Colorado border. Nice place to visit for a drive!

Matt and '69:

And isn't Utah the place where many of the auto magazines and manufacturers take their cars for pictures? If I remember correctly when I've driven through the state, there are some gorgeous road and vistas, and being in the mountains, this State is second only to California for great Porsche and motorcycle (Sport Bikes, not Harleys)country ....Andras

Thanks for the replies guys. Your throttle bodies look excellent in the photos Bill, especially with the replating. Did you note how far closed they should be when resting on the screw in stops? Fully closed or open a bit? I suppose you bored them out to RS specs too and fitted new butterflies.

Ahhhh, Salt Lake City sounds like a great place for a 'childhood'. Mountain roads most definately are Porsche roads. Fortunately it will be living out it's retirement in similarly scenic places. The North island (where I live ) is good, but the South is something else! I have it on good authority that affluent European Ferrari owners freight their cars there just to eat up some miles away from the congestion on their roads.
Ever get that feel sometimes when you're on a particular stretch of fast winding road that everything just comes together and the only thing numbing your concentration is the sore smile muscles on you face??

I've talked to the guy that rebuilt the pump for me , he said just make the arms so they fit so that by connecting them you don't move anything. As far as the throttle bodies and those arms I don't know anything about them. I had my throttle bodies rebuilt and they came back all set up I will look to see if they look closed or slightly open. I can also call the guy he has been very helpfull in the past.

Also I'm sure purists would scoff at not using the protracter etc.

I'm with you there, Matt. The zen of Porsche. I took the long way to work this morning....

Thanks Mackgoo. Hey, you've got to believe me when I say I'm not out to offend the purists! I'm one myself (or at least I'd lke to believe that!)

I just couldn't work out how the protractors tied in with everything if there was limited opportunity to change much to make the readings different. I WILL use protractors if needed, so I'm definately not skimping on things. If you have a look at how the whole mechanism works carefully you may appreciate my point- although I don't doubt you already have. There seem to be two separate issues for me:

*correlation of the pump lever to the two main throttle body levers.

*But this only makes sense if firstly the individual butterflies are in sync. If they arn't then the above correlation would still be off.

If anyone has used the protractors here, what happened? Was anything out by much, and did getting the 'basic adjustment' spot on sort everything out? I'd be keen to know.

------------------
'72 911 TE

A littile off the subject but sort of related. How does the hand throttle interface with the system? Also just a side note, The manuale does say after the CO adjustment that really the test is the test drive for the final check. All of this are starting points. There can be fine tuning based on how "transisition speed performance", "constant driving RPM", "start up operation".

mackgoo, my understanding of the hand throttle w/ mfi or carbs is that it is simply a lever-acutated mechanism to pull and hold the normal throttle cable at a fast-idle position. I could be wrong, but I don't think it interacts with the MFI system per se at all, just the normal accelerator linkage.
Chris C.
70 911E Targa (w/ just rebuilt MFI)

Chris is correct. All it does is manually push/pull? the throttle rod at the accelerator end. No interaction with the Mfi at all. Nice to have it working tho!

The question is where does it interface, how does it connect?