VW Baja ROTARY install - Page 2

Jeff20B · 10-26-2008, 04:00 PM

A couple shots of the exhaust. I used a correct 30° collector and all thickwall mild steel pipe from Racing Beat. The two 'hotdogs' are glasspacks. The small one is from a friend's baja and seems to be of better build quality than a typical cherry bomb from the auto parts store. The big one is a Rotary Engineering glasspack that is nearly 20 years old and did a great job quieting my 20B. The small one is over ten years old and quieted his VW powered baja well enough (it can be seen here). The paint is mainly for rust prevention but does look decent. It's a high temp paint. I expect the u-bends to get hottest and help quiet things down as the exchaust gasses change direction; a convenient way to take energy out while not necessarily restricting flow. Velocity should remain high at low RPM for good power from idle up to where all the curves begin to cause restrictions. If this system runs out of breath by 6 or 7 grand, that is just fine.

StreetRx7 · 10-26-2008, 04:12 PM

hmmm very different .. looking good tho..

PercentSevenC · 10-27-2008, 12:08 AM

Wow, that actually looks really nice.

rotorhead87 · 10-27-2008, 05:47 AM

I'm surprised to hear that your glasspack survived that long on your 20b. Everything looks great. I definitely want to see a video of your car rippin' it up off-road.

Jeff20B · 10-27-2008, 03:37 PM

I should have been more clear about that. What I should have said was I briefly tried the RE glasspack on the 20B and it quieted it quiet well. Before then it was situated in a dual pipe exhaust system, along with a few other RE glasspacks, on a rotary truck. Some glasspacks close to the engine lost some of their packing while the ones further away survived. This glasspack was in the middle and it survived pretty well (its mate, installed parallel on the other pipe, was not as fortunate and is louder-ish on percent's 7).

I expect it to keep the baja's 13B at a reasonable volume level for a while and I'm counting on the u-bends to take some of the bite out of the exhaust pulses, like how a turbo can tame rotary exhausts allowing the use of less restrictive straight through mufflers like Borla in the cat location close to the engine, without causing a droning or otherwise excessive and unpleasant noise levels, as would occur in NA form if not for 'presilencers' and the like.

When you've heard as many rotaries as I have, you honestly start wanting a quieter system after a while. It sure will be great if the small glasspack survives as well as the big one has so far.

I have a feeling this system will sound decent. I'll have to get a video or something once it's running. Gotta break it in first, of course.

Phoenix7 · 10-27-2008, 03:53 PM

impressive...so, this is the dumb question: How does the bug handle? I assume it will be a cruiser but I've never been in or around a bug, let alone a rotary one.

WE3RX7 · 10-27-2008, 04:08 PM

I'm impatient for this build to finish and it's not even mine, lol.... looking good!

Jeff20B · 10-27-2008, 04:29 PM

I don't know about a normal bug. This is a baja and certainly doesn't handle as well as a street bug due to being slightly lifted and all that. Also with the added weight in the back, it tends to shift the weight bias rearward a bit. Zenjoe says the rotary weighs 40 pounds more than an air cooled engine. That's all I have to go on, and I know it's probably not very accurate for my setup. I went to great lengths to keep the weight low by using the lightest side plates that were compatible (Y castings), a 2nd gen aluminum waterpump, a 1st gen aluminum water pump impeller (they're both aluminum and probably wouldn't be strong enough with a clutch fan, but I'm using electric so I'm good). The radiator is somewhat heavy(duty) out of an RX-4, but it fits the best and I didn't have to extend the push bar rearward as would have been necessary with a 1st gen radiator and bigger fans. I only added a 3" section to the upper bars to level the push bar because the PO tweaked it upward trying to gain an extra half inch of ground clearance or something. I had to level the bar because it was running into the oil pan lip. I also kept the exhaust short and sweet.

The only thing I didn't bother lightening is the intake manifold. It's just a stock aluminum one with a stock 13B Hitachi carb, so not much weight can be saved by trimming the manifold. I already trimmed another manifold of the same model for my MG Midget 13B project, which will be featured in this section next (you can't wait!). The weight difference is very small compared to the very big effort it took to trim it to fit the small engine bay of the MG. It's not worth it to trim the one for the baja.

Things like ignition coils will probably be mounted on the firewall to keep as much weight as possible away from the extreme edge of the car. I'll also eventually like to get away from the stupid fuel cell inside the car and get a high volume stock style gas tank for the front of the car to help even out the weight balance a bit.

Jeff20B · 10-28-2008, 03:57 PM

I'm having a little trouble mounting the coils. I could mount them like Zenjoe on top of the engine, or on the side firewall, but it's kinda flimsy there. So far I've mounted a single coil holder on the engine for trailing, and I've got two other coils together in a double mount from an FB (these are for DLIDFIS). Where and how should I mount them?

I did have success installing both cooling fans on the radiator and test running them. They both blow the correct direction now (that's kind of important) so the next step is installing the temp sensing bulb of the thermocouple/thermostatic switch to turn the fans on and off. I should probably use a relay because it can handle 30 amps while the thermoswitch is only rated for 16.

Jeff20B · 10-29-2008, 02:40 AM

And each fuse in each fan's fuse holder is rated for 20amps. It's not like each fan will consume a full 20 amps each, but they do spike right as they turn on.

I got the coils mounted as best as I could to ther side firewall using an RX-4 coil holder backing plate and FB front plate. Also made an ignitor heat sink plate and got it installed up and out of the way. Then I started on the wires. The driver's side of the bay is complete (that's the intake/exhaust side so not many wires). The passenger side is where all the action is. I have to figure out some fan wires, pickup signal wires, alt voltage sensing wire, power wire for the DLIDFIS ignitors and coils, thermoswitch wires, relays for the ignition and fans, headache time.

WE3RX7 · 10-29-2008, 10:54 AM

Its all the little stuff now I'm sure that's holding you up!

Pics when you can

Jeff20B · 11-03-2008, 02:30 PM

I've gotten a bit more work done but took a break when I couldn't figure out where to mount the heater core. Any ideas?

I'll post up more pics when the heater core hoses are routed.

N.RotaryTech · 11-07-2008, 01:10 PM

Nice job so far.
I like the engine color.

Jeff20B · 11-08-2008, 11:12 PM

Thanks. I wanted the setup to have good taste.

Ok, I've decided that a heater core isn't necessary just to get the engine test fired so I'll just hook up the beehive and rig up a quick rain guard engine cover so I can test run this beast. It's our rainy season here now so that's probably a good idea. I'll grab a few pictures when the hoses are hooked up.

I'll revisit the heater core once I've figured out a good location for it (and experience enough shrinkage to need a heater lol).

WE3RX7 · 11-09-2008, 05:39 PM

What region are you in that its rainy season? Arizona/Utah/New Mexico??

10-27-2008, 05:47 AM	#19
rotorhead87 Rotors > Pistons Join Date: Sep 2008 Location: Port Saint Lucie, Florida Posts: 316 Rep Power: 17	I'm surprised to hear that your glasspack survived that long on your 20b. Everything looks great. I definitely want to see a video of your car rippin' it up off-road. __________________ *UPDATED 06/15/2009* Check out My VMIC Turbo 13B-RE FC3S build

10-27-2008, 03:37 PM	#20
Jeff20B Rotary Fanatic Join Date: Mar 2008 Posts: 215 Rep Power: 18	I should have been more clear about that. What I should have said was I briefly tried the RE glasspack on the 20B and it quieted it quiet well. Before then it was situated in a dual pipe exhaust system, along with a few other RE glasspacks, on a rotary truck. Some glasspacks close to the engine lost some of their packing while the ones further away survived. This glasspack was in the middle and it survived pretty well (its mate, installed parallel on the other pipe, was not as fortunate and is louder-ish on percent's 7). I expect it to keep the baja's 13B at a reasonable volume level for a while and I'm counting on the u-bends to take some of the bite out of the exhaust pulses, like how a turbo can tame rotary exhausts allowing the use of less restrictive straight through mufflers like Borla in the cat location close to the engine, without causing a droning or otherwise excessive and unpleasant noise levels, as would occur in NA form if not for 'presilencers' and the like. When you've heard as many rotaries as I have, you honestly start wanting a quieter system after a while. It sure will be great if the small glasspack survives as well as the big one has so far. I have a feeling this system will sound decent. I'll have to get a video or something once it's running. Gotta break it in first, of course. Last edited by Jeff20B; 10-27-2008 at 03:39 PM.

10-27-2008, 04:29 PM	#23
Jeff20B Rotary Fanatic Join Date: Mar 2008 Posts: 215 Rep Power: 18	I don't know about a normal bug. This is a baja and certainly doesn't handle as well as a street bug due to being slightly lifted and all that. Also with the added weight in the back, it tends to shift the weight bias rearward a bit. Zenjoe says the rotary weighs 40 pounds more than an air cooled engine. That's all I have to go on, and I know it's probably not very accurate for my setup. I went to great lengths to keep the weight low by using the lightest side plates that were compatible (Y castings), a 2nd gen aluminum waterpump, a 1st gen aluminum water pump impeller (they're both aluminum and probably wouldn't be strong enough with a clutch fan, but I'm using electric so I'm good). The radiator is somewhat heavy(duty) out of an RX-4, but it fits the best and I didn't have to extend the push bar rearward as would have been necessary with a 1st gen radiator and bigger fans. I only added a 3" section to the upper bars to level the push bar because the PO tweaked it upward trying to gain an extra half inch of ground clearance or something. I had to level the bar because it was running into the oil pan lip. I also kept the exhaust short and sweet. The only thing I didn't bother lightening is the intake manifold. It's just a stock aluminum one with a stock 13B Hitachi carb, so not much weight can be saved by trimming the manifold. I already trimmed another manifold of the same model for my MG Midget 13B project, which will be featured in this section next (you can't wait!). The weight difference is very small compared to the very big effort it took to trim it to fit the small engine bay of the MG. It's not worth it to trim the one for the baja. Things like ignition coils will probably be mounted on the firewall to keep as much weight as possible away from the extreme edge of the car. I'll also eventually like to get away from the stupid fuel cell inside the car and get a high volume stock style gas tank for the front of the car to help even out the weight balance a bit. Last edited by Jeff20B; 10-27-2008 at 04:32 PM.

11-07-2008, 01:10 PM	#28
N.RotaryTech Home-brew Rotary Join Date: Feb 2008 Location: GooseCreek SC Posts: 552 Rep Power: 18	Nice job so far. I like the engine color. __________________ '89 RX7 GTU, half-Bridge-port S4/S5 NA, E6K, Full RB exhaust, weekend warrior. '83 RX7, The "this might take awhile" project. '87 RX7 GXL, Rest In Pieces. '98 Subaru Impreza Outback-sport, rx7 rescue vehicle, down for repair. '94 Ford Ranger, daily.

10-26-2008, 04:12 PM	#17
StreetRx7 Rotary Fanatic Join Date: Oct 2008 Posts: 37 Rep Power: 0	hmmm very different .. looking good tho..

10-27-2008, 04:08 PM	#22
WE3RX7 RCC Addict Join Date: Feb 2008 Location: VA Posts: 1,812 Rep Power: 19	I'm impatient for this build to finish and it's not even mine, lol.... looking good!

10-28-2008, 03:57 PM	#24
Jeff20B Rotary Fanatic Join Date: Mar 2008 Posts: 215 Rep Power: 18	I'm having a little trouble mounting the coils. I could mount them like Zenjoe on top of the engine, or on the side firewall, but it's kinda flimsy there. So far I've mounted a single coil holder on the engine for trailing, and I've got two other coils together in a double mount from an FB (these are for DLIDFIS). Where and how should I mount them? I did have success installing both cooling fans on the radiator and test running them. They both blow the correct direction now (that's kind of important) so the next step is installing the temp sensing bulb of the thermocouple/thermostatic switch to turn the fans on and off. I should probably use a relay because it can handle 30 amps while the thermoswitch is only rated for 16.

10-29-2008, 02:40 AM	#25
Jeff20B Rotary Fanatic Join Date: Mar 2008 Posts: 215 Rep Power: 18	And each fuse in each fan's fuse holder is rated for 20amps. It's not like each fan will consume a full 20 amps each, but they do spike right as they turn on. I got the coils mounted as best as I could to ther side firewall using an RX-4 coil holder backing plate and FB front plate. Also made an ignitor heat sink plate and got it installed up and out of the way. Then I started on the wires. The driver's side of the bay is complete (that's the intake/exhaust side so not many wires). The passenger side is where all the action is. I have to figure out some fan wires, pickup signal wires, alt voltage sensing wire, power wire for the DLIDFIS ignitors and coils, thermoswitch wires, relays for the ignition and fans, headache time.

10-29-2008, 10:54 AM	#26
WE3RX7 RCC Addict Join Date: Feb 2008 Location: VA Posts: 1,812 Rep Power: 19	Its all the little stuff now I'm sure that's holding you up! Pics when you can

11-03-2008, 02:30 PM	#27
Jeff20B Rotary Fanatic Join Date: Mar 2008 Posts: 215 Rep Power: 18	I've gotten a bit more work done but took a break when I couldn't figure out where to mount the heater core. Any ideas? I'll post up more pics when the heater core hoses are routed.

11-08-2008, 11:12 PM	#29
Jeff20B Rotary Fanatic Join Date: Mar 2008 Posts: 215 Rep Power: 18	Thanks. I wanted the setup to have good taste. Ok, I've decided that a heater core isn't necessary just to get the engine test fired so I'll just hook up the beehive and rig up a quick rain guard engine cover so I can test run this beast. It's our rainy season here now so that's probably a good idea. I'll grab a few pictures when the hoses are hooked up. I'll revisit the heater core once I've figured out a good location for it (and experience enough shrinkage to need a heater lol).

11-09-2008, 05:39 PM	#30
WE3RX7 RCC Addict Join Date: Feb 2008 Location: VA Posts: 1,812 Rep Power: 19	What region are you in that its rainy season? Arizona/Utah/New Mexico??