New 2.8 Liter Six for the Racecar, I'll be asking a bunch of Conversion Questions Options

[motorvated]

The first question I have is related to modifications to the engine shelf pieces required for the 6-cylinder conversion. I noticed the Patrick Motorsports sells an expensive engine shelf kit for the 6-cylinder conversion. But, since the 6-cylinder is going into a Racecar, can I just cut out the entire engine shelf to maximize the available space in the engine compartment? Or, has anyone made a template that can be used to modify the 4-cylinder engine shelf to accommodate the 911 engines? I'd like just to remove the shelf parts if they are not needed. Thoughts on this? How do you other racers handle this. Many more questions to follow. I know there are many conversion threads out there, but it's hard to weed through them to see if they address the question(s) that I have. Plus most of Tigre are for street car conversions, not race cars.

Mike S.

[stownsen914]

You mean the engine tin, or the horizontal shelf that's attached to the chassis in front of the engine?

On my /6 racecar I got rid of both*. When the car is moving, the sheet metal doesn't perform as important a function as when the car is moving at low speed or standing still.

* footnote - when I flat bottomed the car and put a diffuser on the back, I needed to add engine sheet metal back in to keep the engine bay from getting to 200+ degrees.

[GregAmy]

Ditto on my /4: no tin surround, it's all trimmed off. I don't even run the one that separates the engine from the transaxle area.

I got that idea from Chris Foley, who did that on his race car with his vertical fan system.

[Charles Freeborn]

Mine has all the tin removed too - "firewall" between engine compartment and rear trunk is still there, but the floor of the trunk area is removed allowing easier access to CV's and starter.
I'm overdue to photograph mine - been too busy working on it. I'll snap some pics next time I've got it up in the air - hopefully soon.

[motorvated]

Mine has all the tin removed too - "firewall" between engine compartment and rear trunk is still there, but the floor of the trunk area is removed allowing easier access to CV's and starter.
I'm overdue to photograph mine - been too busy working on it. I'll snap some pics next time I've got it up in the air - hopefully soon.

That would be great! Thanks.

[brant]

I’m not running any engine shelf or tin either.


Did you get conversion parts with the motor?

[motorvated]

I’m not running any engine shelf or tin either.


Did you get conversion parts with the motor?

Drivetrain came out of another 914, but the only conversion part that came with it is the engine half of the front engine mount. So I will need engine oil tank, external oil cooler (?), transaxle pump and cooler, headers, etc. I also need a dual plug distributor. So if anyone out there has anything on a shelf in their garage and wants to sell it, please let me know.

[BillJ]

Many go with JB Racings distributor. Jbracing.com

[motorvated]

Many go with JB Racings distributor. Jbracing.com

JB Racing distributors look like they are just what I'm after. Since I do not yet know much about these 911 motors, does the distributor rotate counterclockwise?

[infraredcalvin]

My -4 has FAT 911 fan shroud with no additional tin and a shrouded rx7 cooler up front, engine shelves on chassis remain in place.

My -6 is more of DE/track than street, but I do take it on the street still, but I run fiberglass engine tin. I have a non shrouded cooler up front with dual fans.

Both run 180-210 on 110 degree track days.

I have an Electromotive crankfire ignition, on the dual plug 6. Old tech, but seems to be easy to tune once installed correctly…

[Charles Freeborn]

I’m not running any engine shelf or tin either.


Did you get conversion parts with the motor?

Drivetrain came out of another 914, but the only conversion part that came with it is the engine half of the front engine mount. So I will need engine oil tank, external oil cooler (?), transaxle pump and cooler, headers, etc. I also need a dual plug distributor. So if anyone out there has anything on a shelf in their garage and wants to sell it, please let me know.

Not great, but here are some pics of my engine compartment. My engine has a 911 style (FAT Perf.) fan shroud so it's similar to your 6 cyl fit, but more space between fan and firewall. I do have a dry sump with the oil tank taking up some of the drivers side engine compartment. 6 installs typically put the tank up in the front trunk. My car has 2 coolers in front with lines back to the tank. I'll take pics of that soon too.

Rear trunk area cut out for access to trans, cv's etc


The original "shelf" with the channel for weatherstripping is mostly intact, but cut away where air ducting from the front was channeled back to the engine. With the 911 type shroud and no engine "side tins" it leaves quite a bit of gap between engine and firewall / engine compartment


Oil tank is on the drivers side against the firewall. As said. with a 6 there's probably not room back here so most people put the tank in the front. Mine is a 4 so it has a 1.5 gal tank. You'll want a bigger one for as 6.


I'm overdue to put together a photo thread on this car. It's pretty well built. I'll try to get to that soon - ish....

[BillJ]

Depending on where you want to drive the car be careful about what you cut out. Many vintage groups will not let you run with the trunk cut for example. Read the rules of where you want to race if that is your goal.

You should also consider the stock location and style for the oil tank. I have run in the front as well on a conversion car I owned in the past.

[brant]

Many go with JB Racings distributor. Jbracing.com

JB Racing distributors look like they are just what I'm after. Since I do not yet know much about these 911 motors, does the distributor rotate counterclockwise?

they will sell you one either direction of rotation depending on the crank/distributor gear you are running.

I also use this distributor.. but build the motor with a 3.0 distributor gear for rotation

[BillJ]

Quick question. Why a 2.8? For most groups that makes you too large for the 2.5 group and underpowered for the 3.0 rsr cars we race against....

I went from my 2.7rs down to 2.4 to race with that group.

[motorvated]

Quick question. Why a 2.8? For most groups that makes you too large for the 2.5 group and underpowered for the 3.0 rsr cars we race against....

I went from my 2.7rs down to 2.4 to race with that group.

This drivetrain simply found me and not the other way around, so that's why the 2.8 liter motor. I mostly race with RMVR here in Colorado and have been running with their Small Bore group of 2.0 liter and under. With the 2.8 liter I'll be running with their Mid/Big Bore group, as I would with a 2.4 or 2.5 liter motor. So not much difference unless I venture out and run with other Vintage clubs, which I do from time to time. As long as I have a few others to race against and I'm not running alone all the time, I'm happy.

[brant]

Is it a hemmigway motor?
Or 2nd guess. Matt in castle rock?

[BillJ]

Makes sense and sounds like you have the perfect attitude to just have fun!!!

[gms]

engine shelf left in, no engine sheet metal installed

[Charles Freeborn]

Quick question. Why a 2.8? For most groups that makes you too large for the 2.5 group and underpowered for the 3.0 rsr cars we race against....

I went from my 2.7rs down to 2.4 to race with that group.

This drivetrain simply found me and not the other way around, so that's why the 2.8 liter motor. I mostly race with RMVR here in Colorado and have been running with their Small Bore group of 2.0 liter and under. With the 2.8 liter I'll be running with their Mid/Big Bore group, as I would with a 2.4 or 2.5 liter motor. So not much difference unless I venture out and run with other Vintage clubs, which I do from time to time. As long as I have a few others to race against and I'm not running alone all the time, I'm happy.

I'm in a similar boat with my displacement at 2.6. SCCA VP2 is up to 3.2L so, I'm not likely to be very competitive - depending on the track.. Portland Intl, where I mostly run does not favor the better handling cars as it's fast and flat. That said, with run groups not being what they used to be, the VP1 cars (up to 1.9L) run in the same heats so there's always traffic (slower and faster) to play with.
The other vintage sanctioning bodies that run around here (SOVREN- Seattle based, and SVRA - Nationwide) would probably place me in some sort of GT class or another, not so much for displacement but for bodywork. Again, probably not going to podium, but there's lots of good racing to be had.

[BadToTheBown]

Mine is all removed, great access to everything...