S4 EFI 13b into street bug
04-14-14, 10:13 AM
#51
Any progress on the beehive install? I have an update for you. I can say they will fit 100% now because I just completed an S4 NA install in the red FB. It has a beehive and it fits perfectly with the UIM and throttle cable position. I just had to extend/redo the cable bracket to work with the 12A carb cable. Another option would have been to swap in a GSL-SE cable but we didn't want to do that. I'm sure your VW cable has already been modified, right? 
05-19-14, 11:44 PM
#53
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Nothing to report I'm afraid. I'll get back to it though.
I haven't set up the throttle yet, but I have an extremely heavy duty cable (think automatic transmission shift cable) that is the right length to go from the pedal to the manifold.
I haven't set up the throttle yet, but I have an extremely heavy duty cable (think automatic transmission shift cable) that is the right length to go from the pedal to the manifold.
05-22-14, 01:16 AM
#54
Cool. I swapped a bracket on my carb to work with my throttle cable. I also completed a fuel system the other day. Now it's compatible with NA carbs, or a turbo blow through or EFI. Sorta wanted to cover all the bases. It uses an MSD fuel pump and EFI rated hose. Is your fuel system very far along?
I also completed a fuel system the other day. Now it's compatible with NA carbs, or a turbo blow through or EFI. Sorta wanted to cover all the bases. It uses an MSD fuel pump and EFI rated hose. Is your fuel system very far along?
05-26-14, 03:24 AM
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Actually I'm having a difficult time deciding where to put the tank and what size to get. Since the front end is fiberglass/gutted I'm left with: Behind the dash, on the parcel tray, or in place of the back seat. Pros and Cons factor crash safety, weight distribution, center of gravity, retaining the back seat and room for stereo/speakers, and heat from the radiator if not sealed off well. I'm thinking the dash mount will be best, perhaps an 8 gallon tank to keep it on the smaller/lighter side.
10-31-14, 04:05 PM
#58
It is interesting how long these projects can take as we learn more about them/gather more info in an attempt to make them better and end up changing our plans part way through.
Mine is no different in that regard. I'm still on the fence about whether to go turbo because the tranny is a stock 3 rib and the CVs are stock.
Most people who put a basic turbo in their air cooled street bug or baja/manx, mainly do it to go from a stock 50HP to a more useable 100HP. It's a great upgrade with very useable results and makes the car so much nicer to drive. Also consider how that is twice the power and yet the drivetrain components tend to hold up well as long as they're not abused.
Now consider that the rotary has over 100HP stock and they make great engines in street bugs due to their compactness, lightness (slightly heavier than a bug engine due to the required cooling system etc) and the available adaptor kits, but not so great for a baja due to the larger tires and the rotary's supposed lack of low RPM torque - probably more of a problem for a 12A which most people look into first due to the simplicity of a carb. A ported 12A makes a decent rail engine, for example where starting out in sand is obviously different than starting out on a hill up in the mountains.
Since my current engine began life as a carbed 13B out of a 76 Cosmo, with 110HP at 6k and 120 torque at 4k, I always assumed it would be a great choice for simplicity and power. So I built an engine to mimic that setup and tried it. It turned out most of those internet guys recommending against a rotary in a baja were correct. The low end just wasn't there, and the high end wasn't their either. Later I discovered the carb's fuel inlet strainers were clogged and that this carb (Hitachi) isn't really all that powerful in the first place. Plus it was a fresh rebuild so it wasn't a good idea to get on it hard anyway without any break in time. The second engine I tried was a used 6 port S4 NA with a broken side seal (unbeknownst to me at the time). Here I tried a modded intake manifold where someone welded a 6 port flange to a 12A manifold so I could use a Nikki. Same or similar lack of low end power due to all 6 ports open all the time, but above 4k it came alive! Again those internet guys were right. Good high end power but nothing down low. Back to the drawing board.
I needed to get to the bottom of why the rotary lacks low end so I looked into ways to increase it from a bigger carb like a Holley, Edelbrock, or even a hogged out Nikki, and looked into the power and tq ratings of ACVW 1600 vs old school 13Bs and realised the reason my baja felt gutless down low was because while the ACVW was only rated for 50 to 55HP, its torque rating was what did me in. It was rated for 77 foot pounds at 2600. Wow. For some rotaries, that's right above idle! No wonder that car used to have a good kick between 2 and 3 grand with the bug engine in it. But it had a small Solex carb meant for a 1500 single port on a 1600 dual port engine so it ran out of breath quickly and couldn't run much past 4000. I only ever saw 4500 twice on the tach the entire time I had the air cooled in there. It sounded like it was going to fly apart up there and it took so long to rev that high that it just wasn't worth it to take it much above 3500 on a daily basis. Kinda seemed like I was driving diesel.
Me, coming from the world of rotary power, just couldn't live like that. I certainly wasn't interested in sinking any money onto a bigger bug engine especially when I enquired about them, it was recommended that I go to a 1950cc or bigger when I was thinking 1776 or 1835. When I looked on the internet for info about this 1950 size, in turns out it would be a custom built engine, that would mean big bucks. No thanks. So rotary it was.
Fast forward to now. I'm in the process of testing four boost prepped Nikkis with the hopes that one might end up on the baja. Out of the four, only two actually handle the boost without flooding out constantly. I think the new needles in the seats are getting stuck in a down position every time the mallory fpr pushes fuel in during boost at a 1:1 ratio and need time to break in or "burnish". But one of the these floody carbs runs flawlessly in vacuum with the current turbo tune on the primary circuit; it's great. Just don't boost it! lol. I'm hoping if I can solve its flooding issue, it'll make a great turbo carb for the baja. Otherwise if I can't solve the issue, it'll still make an excellent carb for NA due to its good tip in and strong primary circuit. But there are some issues I've noticed with these carbs in general that if you change the intake manifold to one with a slightly different design with smaller runners, it can mask some idle quality issues through higher velocities etc, but high end power is reduced. Also the test vehicle, my FB, has a mild ported 4 port R5 13B with a big runner manifold while the baja has a stock 76-85 12A port spec on the 76 Cosmo 13B based engine with a small runner manifold. These differences add up. I also have the option of running an original 76 Cosmo reverse runner manifold for even better primary power with the expense of some secondary power (maybe?). But the reverse runner is incompatible with the way the S5 turbo is mounted, so it's for NA-only if used in the baja.
I guess what I'm saying is if I can't solve the flooding issues, this carb runs good enough that it should make a good NA carb once tuned for NA (assuming other variables like manifold size and port size differences don't screw things up too badly). Otherwise if I CAN solve the flooding problem, this carb might just stay in the test vehicle because it runs so well with its current turbo tune. Does that make sense?
Sorry about the manuscript. I know some of it doesn't pertain to your situation but it's good to get it out there and to let you know I'm still actively working on my rotary baja even though I'm not physically working on it right now. But I did test fit an S5 turbo with a rudimentary charge pipe a couple days ago. Yep, it can be made to fit. I just need the confidence to go through with the actual swap and a carb that handles boost without flooding because I don't want to gun it up a snowy hill to keep the tires clean and wind up getting stuck because the carb flooded out. I'm sure I could restart it but one more thing: it does still have the 24volt starter mod but it puts major stress on the starter gear and the flywheel ring gear. You've seen how fine VW starter teeth are. They'll wear down to a nub probably after a year of use. Gotta do a dual battery 12V parallel wiring mod next.
Mine is no different in that regard. I'm still on the fence about whether to go turbo because the tranny is a stock 3 rib and the CVs are stock.
Most people who put a basic turbo in their air cooled street bug or baja/manx, mainly do it to go from a stock 50HP to a more useable 100HP. It's a great upgrade with very useable results and makes the car so much nicer to drive. Also consider how that is twice the power and yet the drivetrain components tend to hold up well as long as they're not abused.
Now consider that the rotary has over 100HP stock and they make great engines in street bugs due to their compactness, lightness (slightly heavier than a bug engine due to the required cooling system etc) and the available adaptor kits, but not so great for a baja due to the larger tires and the rotary's supposed lack of low RPM torque - probably more of a problem for a 12A which most people look into first due to the simplicity of a carb. A ported 12A makes a decent rail engine, for example where starting out in sand is obviously different than starting out on a hill up in the mountains.
Since my current engine began life as a carbed 13B out of a 76 Cosmo, with 110HP at 6k and 120 torque at 4k, I always assumed it would be a great choice for simplicity and power. So I built an engine to mimic that setup and tried it. It turned out most of those internet guys recommending against a rotary in a baja were correct. The low end just wasn't there, and the high end wasn't their either. Later I discovered the carb's fuel inlet strainers were clogged and that this carb (Hitachi) isn't really all that powerful in the first place. Plus it was a fresh rebuild so it wasn't a good idea to get on it hard anyway without any break in time. The second engine I tried was a used 6 port S4 NA with a broken side seal (unbeknownst to me at the time). Here I tried a modded intake manifold where someone welded a 6 port flange to a 12A manifold so I could use a Nikki. Same or similar lack of low end power due to all 6 ports open all the time, but above 4k it came alive! Again those internet guys were right. Good high end power but nothing down low. Back to the drawing board.
I needed to get to the bottom of why the rotary lacks low end so I looked into ways to increase it from a bigger carb like a Holley, Edelbrock, or even a hogged out Nikki, and looked into the power and tq ratings of ACVW 1600 vs old school 13Bs and realised the reason my baja felt gutless down low was because while the ACVW was only rated for 50 to 55HP, its torque rating was what did me in. It was rated for 77 foot pounds at 2600. Wow. For some rotaries, that's right above idle! No wonder that car used to have a good kick between 2 and 3 grand with the bug engine in it. But it had a small Solex carb meant for a 1500 single port on a 1600 dual port engine so it ran out of breath quickly and couldn't run much past 4000. I only ever saw 4500 twice on the tach the entire time I had the air cooled in there. It sounded like it was going to fly apart up there and it took so long to rev that high that it just wasn't worth it to take it much above 3500 on a daily basis. Kinda seemed like I was driving diesel.
Me, coming from the world of rotary power, just couldn't live like that. I certainly wasn't interested in sinking any money onto a bigger bug engine especially when I enquired about them, it was recommended that I go to a 1950cc or bigger when I was thinking 1776 or 1835. When I looked on the internet for info about this 1950 size, in turns out it would be a custom built engine, that would mean big bucks. No thanks. So rotary it was.
Fast forward to now. I'm in the process of testing four boost prepped Nikkis with the hopes that one might end up on the baja. Out of the four, only two actually handle the boost without flooding out constantly. I think the new needles in the seats are getting stuck in a down position every time the mallory fpr pushes fuel in during boost at a 1:1 ratio and need time to break in or "burnish". But one of the these floody carbs runs flawlessly in vacuum with the current turbo tune on the primary circuit; it's great. Just don't boost it! lol. I'm hoping if I can solve its flooding issue, it'll make a great turbo carb for the baja. Otherwise if I can't solve the issue, it'll still make an excellent carb for NA due to its good tip in and strong primary circuit. But there are some issues I've noticed with these carbs in general that if you change the intake manifold to one with a slightly different design with smaller runners, it can mask some idle quality issues through higher velocities etc, but high end power is reduced. Also the test vehicle, my FB, has a mild ported 4 port R5 13B with a big runner manifold while the baja has a stock 76-85 12A port spec on the 76 Cosmo 13B based engine with a small runner manifold. These differences add up. I also have the option of running an original 76 Cosmo reverse runner manifold for even better primary power with the expense of some secondary power (maybe?). But the reverse runner is incompatible with the way the S5 turbo is mounted, so it's for NA-only if used in the baja.
I guess what I'm saying is if I can't solve the flooding issues, this carb runs good enough that it should make a good NA carb once tuned for NA (assuming other variables like manifold size and port size differences don't screw things up too badly). Otherwise if I CAN solve the flooding problem, this carb might just stay in the test vehicle because it runs so well with its current turbo tune. Does that make sense?
Sorry about the manuscript. I know some of it doesn't pertain to your situation but it's good to get it out there and to let you know I'm still actively working on my rotary baja even though I'm not physically working on it right now. But I did test fit an S5 turbo with a rudimentary charge pipe a couple days ago. Yep, it can be made to fit. I just need the confidence to go through with the actual swap and a carb that handles boost without flooding because I don't want to gun it up a snowy hill to keep the tires clean and wind up getting stuck because the carb flooded out. I'm sure I could restart it but one more thing: it does still have the 24volt starter mod but it puts major stress on the starter gear and the flywheel ring gear. You've seen how fine VW starter teeth are. They'll wear down to a nub probably after a year of use. Gotta do a dual battery 12V parallel wiring mod next.
11-03-14, 04:59 PM
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Good to know you haven't given up. I still think you should consider FI for the ease of tuning, but I know you have the carbs (and infrastructure) already.
I'm taking a few steps back with this new roller, but it will save me some work too. I won't be able to use my exhaust system because of the kafer bars and cage bracing around the trans, which leaves me considering going straight for the turbo. Since the front end is uncut, I'm thinking about radiator setups that don't involve hacking up the car any worse than it is. Perhaps I could "hide" it in a roof rack, or custom make a roof rack that is actually a giant radiator in disguise. I'll probably try the parcel tray first since it's already cut out. Perhaps a scoop under the left side that puts the air up through the left half of the rad and back down through the right half, then out under the right side of the car. Before I get to any of that though, I have to play mix and match making one good bug with the best parts from both, and have my front beam straightened while it's out. (Accident that brought the fiberglass tweaked it a little) I hate to step backwards like this but it will be a much nicer ride when done. I also have this plan to get it running as an air cooled bug, and then install all of the plumbing and electronics since the car will be easier to access (can be taken to friends places, etc) and once EVERYTHING is ready, pull it down for a quick(ish) swap.
I'm taking a few steps back with this new roller, but it will save me some work too. I won't be able to use my exhaust system because of the kafer bars and cage bracing around the trans, which leaves me considering going straight for the turbo. Since the front end is uncut, I'm thinking about radiator setups that don't involve hacking up the car any worse than it is. Perhaps I could "hide" it in a roof rack, or custom make a roof rack that is actually a giant radiator in disguise. I'll probably try the parcel tray first since it's already cut out. Perhaps a scoop under the left side that puts the air up through the left half of the rad and back down through the right half, then out under the right side of the car. Before I get to any of that though, I have to play mix and match making one good bug with the best parts from both, and have my front beam straightened while it's out. (Accident that brought the fiberglass tweaked it a little) I hate to step backwards like this but it will be a much nicer ride when done. I also have this plan to get it running as an air cooled bug, and then install all of the plumbing and electronics since the car will be easier to access (can be taken to friends places, etc) and once EVERYTHING is ready, pull it down for a quick(ish) swap.
11-04-14, 12:33 AM
#61
I wouldn't consider EFI easy to tune lol. That is to say my experience with it wasn't one of ease. I find carbs easier to tune. There is so much more to EFI with all the ugly manifolds, wires, sensors and somewhat limited, well, I guess I'm talking about two things here: stock S4 NA EFI and aftermarket EFI. I've installed both and don't really care for either so I'm sticking with carbs.
Of course my car's fuel system is already set up for EFI, if you were curious. Kinda nice having a good foundation.
I like your parcel tray. Go for a radiatior install in it.
Of course my car's fuel system is already set up for EFI, if you were curious. Kinda nice having a good foundation.
I like your parcel tray. Go for a radiatior install in it.
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datfast1
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06-20-19 10:53 PM
