Been thinking about this for a while and don't feel happy to do it but think in the overall picture it is a solution for ease of front engine maintenance for my 2.2T 6.
Comments are welcome from those that have been and done it,thanks

Contrary to what some might say, it is not required for ignition timing as long as your flywheel is properly marked.

I suppose that it would be great for alternator/fan belt maintenance.
I am not sure how difficult that task is without the access panel who has done that??

I did it, I put in an access panel and used it to get the shims right on the engine belt during dial in. Removing/Installing the back pad was the worst part of the whole thing....

Original 6 or conversion ?

It seems most racers have done it to provide quick, easy access to the front of the engine. If it's an original -6, I wouldn't touch it unless the car is already modifies.

My conversion does not have a cut firewall, and I have replaced a fan belt with the engine in the car. I'm not sure it may not be easier to drop and reinstall the engine for the next time.

Actually, I think that dropping the engine to service valves, etc. and clean things may not be a bad idea.

One thing to remember--the word is firewall. If you cut a hole in it, make sure that when it is closed you know that it will keep any engine fires out of the cabin. Positive sealing that does not melt or burn is strongly recommended!! (I.e, an oversized metal cover.)

--DD

Changing the belt is easy if you have the right tool. Alternator is removable as well.

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I agree with Dave. Make sure its still a firewall if you cut it.

Ok that box end wrench custom bent looks pretty nice. I have changed belts on my -6 conversion several times and it is a bit of a challenge. I use a rotating head 1/2 inch drive ratchet and a P-208 Porsche style tool as pictured. The biggest problem I have is getting the shims under outer pulley half to cooperate and and stay centered on the alternator shaft while tightening the nut prior to full torque tightening. Having the bent wrench instead of the ratchet could be helpful. Who bent it up for you and would they/you do this for other 914/6 brothers?

I hate to see these cars cut-up to put P-motors in them...

T

I wouldn't on an Original 6
probably would on a conversion 6

read my signature,cheers.

thanks Glen,you see it in a different light than some that don't have this engine in their car,my plan is to cut the opening and mig in a surround drilled and tapped to hold it in place but have no kind of template?
DD fair comment but I'am not some newbie dumbass...sure you know that .

DON'T DO IT!!!!!

1) a simple steel strip with a few holes in, bolts to the coil mounting studs at one end and a standard Porsche fan tool at the other. This then locks the fan assembly and leaves your hands free. (Or something similar, it's not difficult to come up with something)

2) a thin (THIN) smear of grease on the shims makes them stick together and stay in place while you do the nut up.

3) all timing marks are on the flywheel, there's no need to try & look at the fan pulley.

Whether original or conversion, there's no need at all to cut that firewall, you'll just regret it.

Double post.... Dam iPhone

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I use a rotating head 1/2 inch drive ratchet and a P-208 Porsche style tool as pictured. The biggest problem I have is getting the shims under outer pulley half to cooperate and and stay centered on the alternator shaft while tightening the nut prior to full torque tightening. Having the bent wrench instead of the ratchet could be helpful. Who bent it up for you and would they/you do this for other 914/6 brothers?
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I used the same tools to change and tighten the belt on my 3.2. Easy to do and no big deal. I permanently removed the engine compartment back pad for extra clearance. It caused some surface rust on the battery side, so I was happy to dump it anyway. Unless you can change the alternator on a 3.2 through a firewall hole, then to me it's not worth the hassle

Do It! I did mine and love it! It makes so many things easier.

1) That sounds like a cool set up that works very well. I agree that there is no real need to cut up the firewall as the timing marks are visible back at the flywheel. Would like to try and fab that up! If you have any pics of said pieces that would be cool. Thanks for sharing the idea.

Timing marks on a 914-4 are on the flywheel. On many transplanted engines (911, etc.), they're on the crank pulley.

Sherwood

I'm very sorry for failing to notice that your car is a conversion.
Also, many thanks for being so courteous to my friend Glenn who offered the advise I would have given if you had answered my question.
DD was offering sound advise and not assuming anything.
Access panels have been done every way imaginable.
I cut a section from another 914 firewall.
Why use anything else ? this part is already form fitting and you can use as much or as little as you like.
Even you could do it.

I did it on my track car. I used a sheet of aluminum. Not to thin. It formed very nicely. I welded 8 small nuts to the engine side of the firewall. I am very glad I did this mod. Simple access. I sit in drivers seat and turn and look at the pulley when I am doing the timing. When you check the fan belt tension you can actually see the belt deflection and adjust it. My buddy convinced me to do it. I am so glad I did. I thanked him. Check out the thread in my signature.

Aluminum is lighter. You can avoid the weight of weld in nuts.
I don't regret it after 10 years
And use it 6-8 times a year

(Ran about 8 different belts this summer alone)

Nope, I don't know that. I probably should, but many of the people on here run together in my brain... Probably 'cause I'm getting old.

--DD

I used Stainless Steel on mine, ive seen aluminum melt......

I would say, if anyone here is melting their firewall - patch or not, aluminum or steel - they probably have issues. We use aluminum on our race car builds as heat shields and have never even come close to "melting" them. Again, something is terribly wrong if that much heat is being transferred to the firewall...do you have any pictures (or were you just "mess'in" with us)?

T

Not melting from heat, melting from fire......

I used a cut from a parts car so the curves match up. This was when it was being made, used studs and nuts rather than the wing nuts when done.

Nice! Wing nuts! Sometimes I'm square in my thinking. I formed the aluminum over the firewall before I cut it.

if the aluminum is going to melt....

at that point the whole car is melting and beyond saving
you had best be out before then
there is no lack of protection at safe temperatures with aluminum
The whole car will be an inferno and deadly before the aluminum melts

Glad I did it, makes it real easy to get to the front of the motor

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This one was also created as my Mechanic was afraid the engine might run to hot going across the desert when we drove to Rennsport reunion. (it did not and I did not have to use this one)

It's not that complex: just a steel strip. As you can see, I haven't even cut it to length. But in combination with the C-spanner it locks the fan solid.
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I've got a Euro 3.2: TDC is marked on the flywheel - or maybe I'm just lucky. I've never looked at the crank pulley, even when I could. (Each starter tooth is 2.77° I think - don't quote me)

I just did it myself through trial and error. Wrench in a vice grip and blow torch to heat up. 15/16 is 30mm so any cheap wrench can do.

mine

(car is down to about 1825 now with metal panels)

with Glennnnn and others.

For a conversion car, I almost consider it a "Must Have" item.

RivNuts and a donor car firewall and you're golden,

X2 - fwiw my GT came out of Werks 1 with firewall porthole

- aside from dizzy & belt & timing marks access (really important if you are running a stock 911 flywheel), i have thrice pulled an alternator out thru it

- beats an engine drop any day

on the second alternator job, i enlarged the oem porthole 2" wider on the right side to make it easier

the middle panel of the backpad can be separated, so the only thing you have to pull at the track is that middle piece

- on my car the seat bolsters and rollbar crossbar hold it in place nicely without any extra fasteners; so i can just slide it up & out, and 3 screws later have the access panel off

the rubber plug in the center of the "door" is for putting a socket onto the alternator & turning the engine for vale adj, etc (plugs out of course)