Seabee turbo buggy build

[Big Dave]

I took the buggy out today. I was in 4th gear 4000 rpm maybe 55 /60 mph My old trans will go 65 in 3rd gear. The gearing is so low it may hit 5 lbs boost. I knew it was a sand trans but come on I was going faster than that before in the sand with my t1. In short I hate this trans. it will now cost me another 1500 to re gear it.

Try bigger tires. A set of 33"s or 35"s should bring your gearing up where you want it. Clearance with 3X3s shouldn't be a problem anymore

[seabeebuggy]

every inch adds 1 mph. Not worth the money I think... I will use it at glamis first of march and then a buggy run in Mojave at red rock 7th 8th of march. After that i am pulling the trans . It will go out for new gears. I hope I can sell the other gears. They are new and cost almost 1200$ For someones sand rail in a 002 or 091. it is out of a 5 rib and 4.57 R&P. I hope to sell the to re gain a little cash. I can also sell my old trans for 350$ I am playing with turbo Manx gear combo and a few of mine. I like the taller gears. He has the same ration i had in 1st hes 2nd is smaller just a little . like 8 mph less. I don't remember his 3rd. but his 4th was way too tall for me. It said i could go 126 mph at 5500 rpm's I dropped that one down to 107 mph gear. or a 1.000 4th. Still want to boost but not fly away.

It is hard to say how anything will work. He has a taller 4th than me but likes it. I hat my 4th it was too tall. maybe his efi helps or has a lower end cam.?? what is it turbo manx?

[Turbo_Manx_Maniac]

every inch adds 1 mph. Not worth the money I think... I will use it at glamis first of march and then a buggy run in Mojave at red rock 7th 8th of march. After that i am pulling the trans . It will go out for new gears. I hope I can sell the other gears. They are new and cost almost 1200$ For someones sand rail in a 002 or 091. it is out of a 5 rib and 4.57 R&P. I hope to sell the to re gain a little cash. I can also sell my old trans for 350$ I am playing with turbo Manx gear combo and a few of mine. I like the taller gears. He has the same ration i had in 1st hes 2nd is smaller just a little . like 8 mph less. I don't remember his 3rd. but his 4th was way too tall for me. It said i could go 126 mph at 5500 rpm's I dropped that one down to 107 mph gear. or a 1.000 4th. Still want to boost but not fly away.

It is hard to say how anything will work. He has a taller 4th than me but likes it. I hat my 4th it was too tall. maybe his efi helps or has a lower end cam.?? what is it turbo manx?

Hi Seebee - choosing gearnig will drive you nuts! The best thing to do is try other friends rides that have custom gearing. My buddy had just had an 002 box built with weddle 1-4, his first was a bit high, and 4th wound out too fast. So based on that and what I knew from 20 years in the sand and hardpack, and what I had previously, I picked the perfect tranny ratios for me. THey are probably not perfect for you as everyone is looking for something a little different, but I can grubble over and up anything when I do rock climbing, when I race up a hill my first gets the car moving faster than a stock 3.80 does, and the 1-2 shift is perfect, it keeps my turbo motor right in the sweet spot. The 2-3 shift is again a close shift, then 4th is just right where I can fly off road, but still run on the street for a long highway run if I need.

I was more concerned about the rpm drop on shifts, rather than how fast each gear went. You want a longer ratio for a turbo motor, but want to stay in the sweet spot. Too long a gear and you go out of the power band, and too short does not let the turbo work.

Again, I run a 31" tire on my Manx and have similar power to you.

[seabeebuggy]

I am going to use the gears you said except 4th. I don't know enough about that gear and your set up. I would get hot temps and low boost like 5 lbs if I was lucky and it would struggle to gain speed. My gear set up gave it a 127mph at 5500 rpm.
your 4th gear gives you 120mph at 5500 not much difference.
my thinking is 1.000 4th gives me 107 mph at 5500. I don't know if it will be good enough to let boost overcome speed with out running out too fast. NOT that I want to go 107 mph

My shift speed is 5000 rpm, my RPM with the t1 trans in 4th was 3141rpm it was a dog. It would climb but so slow. It was more of a maintain speed gear or a get out of 3rd because it is noisy gear. 127mph max

The shift point on a 1.000 4th is 3597. A bit more rpm and still not as steep of a gear. Will it run out fast? 107 mph max

Turbo manx gear (0.890) rpm range is only 60 rpm higher than my lass trans that was too tall. So is my thinking correct that this gear is going to be too tall ?


Crap I have been at this for 5 hours. It is crazy.

I have more stinking graphs and I am sitting here shifting in my head replaying how it use to be. NUTZ

I am looking at my old rpm shift drops My first to second was 2240rpm drop. This is why second was a long power gear it did need a little to spool. Like 500 to 700 rpm to get to the Balls to wall power. There is a 530 rpm difference from me to Manx 2nd gear. I believe it would be in the Power band. just not a long gear. 10 mph lower than mine 2nd gear was the best power gear but it could be shifted over to 3rd gear for the thrill gear. right?

My 2nd to 3rd rpm drop was 1442, manx drop is 1800. so this gear has more climb time. before shifting. yet it is 400 less rpm than my power 2nd gear.


3rd to 4th my drop was 1858 and manx is 1800. This did not work for me in the past so i am not sure about it.. I am leaning to the 1.00 gear or close to it. the 1.000 has a 1400rpm drop. only 400 less than the other 2 set ups. Will it work? who knows. I think there is something different in engine power or where the power is on our cars.. My car had a mid power band. starting about 2500 to 5000. Where is your best power turbo Manx?

What is you engine combo?

mine 2006 tcs20 cam 125 rockers 40x37.5 heads? I forgot?? 35.5?
ported polished. t3/t4 turbo 63 ar hot side 50 cold . 1.5 header. duel webers..

[Turbo_Manx_Maniac]

Seebee, I feel your pain...I too spent countless hours agonizing over the decision.

A suggestion would be to not look at actual rpm drops, but the percent change from gear changes. As an example, compare a 3.8 to 2.06 stock ratio to a 3.44 and 2.25 and you'll see that my setup gives you more mph in first, and the rpm drop going to second is less than on a stock tranny, so you stay in the power band.

My setup is not that far from yours. I have 550 lb Manx ( ), I run a 1915 that is injected/Turbo. I run 10-12 psi on the street and 16-18 off-road.

My engine is simple but well built. Most of my money is in the heads, they are 044's 42 x 37.5, with a full port and polish and reconfigured combustion chambers. I run a TCS10 (Sucks donkeys balls) with 1.1's. My intake uses the CB end castings, and the rest I fabbed including the exhaust. I run a Garrett T3 50 trim, and of course there's megasquirt doing the spark and fuel stuff along with the MSD 6A and coil. When in the racing mood, I shift at 6K, but do lug the engine sometimes when cruising the washes. My power band is probably from 2500 to 5500, really similar to yours. I'm curious about your engine though. With a bigger turbo and a bit more cam than me, you should be pulling past 5K, do you just short shift it or does it flatten out at 5K? Before I was turbo and injected I ran dual 40 dells, a web 109 cam and shifted at 6500. You should be pulling much past 5K. BTW, I'm a firm believer that the TCS cams from engle leave a ton of power on the table. My WEB 109 made my 1915 scream, with the TCS10, the motor is not as responsive and off boost is mushy. I had a WEB 121 in a 2499 that also kicked some butt. I don't know why I went away from WEB with this motor, but I guarantee I will never buy another Engle TCS cam.

Anyway, when cruising on the highway in 4th at 60 mph, I'm around 2800 rpm. If I have my boost set at 12 psi, I'll make ~8 psi in ~1-2 seconds if I simply floor it. My car has no problem putting you back in the seat at 60 mph on the highway.

With a 1.00 4th, my car would be revving out too much on the highway. My buddies car has a .93 with 32" tires and he doesn't really like it. I never even considered top speed in 4th, the body feels like it will lift off the pan at 80. I was concerned with acceleration in first through 3rd, and wanted to be able to run on the highway, and not at 4 grand. My tranny is perfect for my situation. Your welcome to come on down and drive it, you're not that far from me.

Send me a PM and I'll give you my phone number if you want to talk about it. I love this stuff....

[seabeebuggy]

ok cool some differences are my car is like 2k with me in it. I am guessing but it has a full cage 2 fuel tanks 17 gal of fuel my big butt. The TCS20 cam goes flat at 5500rpm that is all it goes. I can shift at 6500 in first but that is all. After 5k it starts to die off. sucks! but the good thing is I have less of a change in blowing it up from a over rev. My Rev limiter is at 5500. your heads sound better and the 94's give you more punch low end I think. you lighter. This may be why 4th works well for you and not me. My old set up I down shifted into 3rd to pass anyone. I could go almost 80 with ease in 3rd. but 4th was a dog unless I was maxing out my 3rd. I have had it up to 95 or so in 4th. the turbo was starting to overcome things around 3700 rpms I think it was almost 10 lbs. But you say you friends car is revving out in 4th? what kind of car does he have? Have you ever though of going on a buggy run with the DSB club? we get like 15 to 20 buggys IE manx kind of buggy and go on a 100 mile run in the area. Most ore street buggys and a few are offroad. only a 4 or so are like me. I am willing to drive down to see you.


Now you have me thinking of the 4th gear again. at 70 mph it will be 3600rpm. that is too high. S^%T. Back to the drawing board.

[Turbo_Manx_Maniac]

May buddies car is also a Manx, although he is running a 2.5 subie with a turbo. He runs a 32" tire.

I was joking about the weight, I'm probably at 15-1700 with me in the car.

I never heard of the DSB club, except when I was single, then it was the dreaded sperm buildup club.

The club sounds like fun, let me know when they go out again and I'll see if I can make it. We go out to Ocotillo alot, want to join us sometime? Next trip is March 16th. I was in the Manx club a long time ago, but got kicked out for shifting into second on one of their level 5 runs. That was the slowest damn ride I've ever been on.

Sounds like your old box has some really tall gears in it, or was stock with the 31" tires.

So your a 2006, is that a 78 x 90.5?

[seabeebuggy]

May buddies car is also a Manx, although he is running a 2.5 subie with a turbo. He runs a 32" tire.

I was joking about the weight, I'm probably at 15-1700 with me in the car.

I never heard of the DSB club, except when I was single, then it was the dreaded sperm buildup club.

The club sounds like fun, let me know when they go out again and I'll see if I can make it. We go out to Ocotillo alot, want to join us sometime? Next trip is March 16th. I was in the Manx club a long time ago, but got kicked out for shifting into second on one of their level 5 runs. That was the slowest damn ride I've ever been on.

Sounds like your old box has some really tall gears in it, or was stock with the 31" tires.

So your a 2006, is that a 78 x 90.5?

I Don't like the manx club due to some of the people. They are wound up too tight. The duel sport buggy club is made up of a bunch of people who believe in fun. No club dues or membership. If you want to go you go. The runs are all over and are so much fun. we have on in march on the 7,8,9 at red rock North of Mojave. Off the 14. free camping. Not really any rules. Not a drunken party. Some may drink I don't and its cool. the runs are pre determined for the most part and have places to stop . It is a mix of roads, dirt roads, river beds, rocks and water crossings. Everyone makes it. Truly fun.

yes the 2006 is 78x 90.5 My old box was built for a mix of dirt and street with turbo use on 31'' tires by KCR. He picked the gears. It was a good pick except the 4th. but he had not seen the car.
Man I would love to go on a run with you guys. th 14 is not going to work. Glamis on the 1 week of march wife and kids home, buggy club run at red rock march 7,8 wife and kids home. 14th my b day and my first born B-day is the 11th. In laws in from Utah that week..
I don't run on Sundays but the next time you go out let me know.

Good to know you were joking on the car. I was thinking man that is nothing but glass and engine.

here is a link to the site. http://dsb.yuku.com/

there is a section for future trips . Anyone can add a trip there.

[seabeebuggy]

OK after 10 hours of reading and testing on my kids toys. I think I can use your gears but the 4th will be 0.93
This is a little lower than mine I will just have to down shift to get the RPM's up . With that gear I can run 55 @ 2577 , 65mph at 3050 rpm, 75 @ 3480rpm , 80 @ 3650 , 86 @ 4000 rpm, and if I could get to 5500 rpm's I will go 119mph...

One of the problems besides having to shift into 4th gear was I had high head temps in 4th. 350++
I am not lean. I was told to try more timing. I use to have it set for 32* advance but I turned it back due to some reason I can't remember why....
My head temps always go up in 4th. even if I am just cruising. Imagine when I boost my way up to 90mph ? It has don't this in all boost levels.
I guess it could be the gauge but no matter what it only goes up in 4th and the gauge does not know that.

[Turbo_Manx_Maniac]

Where do you run your Manx most of the time? You won't get a box that's good for Glamis, hard pack, and street cruising all in one.

I don't run the sand, I run hard pack 90% of the time and 10% on the road. So if your looking for my ratios to work at Glamis, you'll find 1,2,3 are OK but you'll never use 4th. At least I don't have the HP to pull 4th in the sand.

I like to run in the hard pack washes at 60-70 mph. I also like to climb up stuff like old waterfalls, and jeep trails. On the street, I want to be able to rip from 0-60. What I had built was a good compromise between my needs. The sand is really a different box all together.

If you want a sand gear box, I'd use a long first gear like a 3.11. That will get you on boost and get you some MPH, then a close second to keep you in the sweet spot like a 2.36. But the long first will not be that great for trying to grubble up rocks, so you have to make a choice.

Remember you have more HP than a stock bug, so a 3.80 is much to high a gear, you get no speed from it, and then the stock second is too big a gap.

Soo many choices...

[seabeebuggy]

I want to be dirt street then sand. My last trans went in the sand just fine. It took a little more work to get RPM's up in 2nd , sidestepping the clutch to get the boost up. I think by having a slightly lowed than stock 2nd will help. Over all sand washes and dirt roads rule... Sand is fun but I can still do that and I think the 002 will hold up much better than the t1 trans. I like to go fast In the sand its a blast. going up big hills was OK in 1st and 2nd. I like the rolling smaller stuff the best I can go fast . I will leave the big stuff for the 1% and take my quad . Now all I need is 1500$.

[seabeebuggy]

Took the buggy out for a drive sat. It was kind of fun. I was testing shifting like from 1st to 3rd then 4th or 2nd to 4th. Skipping 3rd works well. skipping 2nd works well too if I rev it up. I still had crap boost . I figured out the Bone head at the shop put my boost line on the wrong port in the BOV. So on boost it would open the BOV. Ireally need to check my enging when it come back from the shop. They screew up many things on my car.. My car is quite crazy. I fixed the line but it has been raining since then.

[Leatherneck]

What a mech, switched the hose, attention to detail and knowledge seemed to be lacking on that one.

[seabeebuggy]

What a mech, switched the hose, attention to detail and knowledge seemed to be lacking on that one.

The owner builds everything but lets his newbie young kid install it. I have complained a few times about the lack of attention to detail. I helped him remove it last time due to his dumbass. The owner is good. I should know better to inspect everything. Matter of fact I made the new vacuum set up independent of everything. I don't know why it was removed. only 1 connection to map needs to be removed... I better check that too.

[hotair]

Nice Buggy...I really like the white paint, really fresh!