I am curious on how hard it is to convert my intake & throttle Body from an 87 NA to an 89 NA.

Will this make the MAF obsolete?

How much work is envolved in this?

Has anyone else done this, because I have heard it was a common thing but i can't find much info on it.

 

You would still need the AFM, you would need to make some custom set up for the MOP.

There are no gains, or even valid reasons to do this change... what are you thinking this will do???

 

The main reason i would do it hopefully would be to get rid of the "ugly box" (as My girlfriend calls it" on the intake tubing, I believe it is the MAF but could be wrong, other than that i was told it is less restrictive, and gives small torque gains.

I don't know if it is true or not, thats why i started the thread

 

The FC uses a AFM (Air Flow Meter), I think that is what you are thinking

And the only way to get rid of it is to go to a stand alone ECU like a Haltec.

 

Isn't Haltech a difficult thing to set up and use?

 

I've heard switching to an S5 intake manafold gives gains, but this has nothing to do with the AFM. post some picks of what you're refering to as the MAF.

 

using the S5 non turbo intake UIM manifold port matched to a S4 LIM will result in gains in HP on a S4 non turbo, but the AFM swap and throttle body swap that chasedrk1 is suggesting would be un-related and a waste of time and money for the HP gain as that gain would be less than minimal.

And chasedrk1, a Mass Air Flow sensor usually uses a Hot wire set up not a cone (like the S5) or a Flapper door (like the S4, Supras, Miata's etc) Air flow meter.

 

you can get rid of the ugly "black intake box" if thats what your asking, and go with a cone filter, best is to make a true cold air and route piping up to the front in the bumper area....

the only S5 intake component thats worth while to change. like icemark said is the upper intake manfold with VDI, you need a rpm switch or somthign to acivate it tho... and it will give you a hp gain , above 5800 rpm

 

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&category=33557&item=79 86640825

 

I suc at inserting pictures! I guess it is to technical for me!

Damn It! just cut copy link

 

yeah... you can't swap that unless you get a stand alone, then you don't need one.

 

They all be MAF. MAF refers to any system that directly measures the amount of air coming in instead of just approxiamating using other sensors (like n alpha or speed density does). Hot wire is just a better design that isn't as restrictive as the flapper door.

http://www.carcraft.com/techarticles/24549/

 

Not true. MAF stands for mass airflow, which is exactly what a hot-wire AFM measures. The flap and cone AFM's FC's have do not measure mass airflow, they only measure volume flow. The air temp must also be measured (density being proportional to temp), and the ECU uses these two measurements to calculate mass airflow.

 

Ahhh, thanks for the clarification. Wonder if there are any hot-wire MAF systems that might be made to work on a FC. Probably would require a standalone to make use of it if it ever worked.

 

Flap/cone AFM's have a completely different output to hot-wire AFM's, so electronics are required to convert the signal. Not really worth it IMO. And if you had a standalone you wouldn't need any AFM.

 

From How to Understand, Service and Modify Bosch Fuel Injection and Engine Management by Charles O. Probst

Pg 6-17: There is no real need to go to a larger air-flow sensor to increase flow capacity...

Pg. 7-17: L-Jetronic systems at high rpm are limited more by available injection pulse time than by air flow restriction. Only a highly modified engine would stand any chance of benefiting from larger intake air-flow components. ...there are other more important considerations. In other words this confirms the sentiments on this forum, that the S4 air flow meter isn't really a restriction and that it's not a restriction worth mentioning until you have an engine producing power well beyond what the stock injectors are capable of.