Boom_Stick

I made some changes to my Genny and now I need to make another mod to make my changes work.

I need to go with a single shock setup with the rear loaded as hard as possible. Infact, I need it loaded as if there were no suspension (You get the idea). The reason being is after I changed my pipe/header and tuned out my .46, this truck can never keep its front wheels on the ground. When I made the header change, I did it to see how the truck would re-act with only one shock on the rear (both sides of course). By using only one, it enabled me to roll a very nice exhaust setup which even fixed my half-tank issue (I can explain more on that later). So now my hunt begins...

FYI: When I say can never keep the front wheels on the ground, I mean ANYTIME the gas is hit the front wheels dance off the ground. The only time they come actually sit is when the truck is at full speed. This is creating a ton of lost power, so I guess I want to load the rear to hold level (or near) during accel. I plan on checking into this, because if I find/build a rig that works, it will allow us to use a wide range of headers/pipes and not have our suspension suffer. I for one can't believe the raw torque this thing has, and setting it up with an exhaust that is designed for more torque just makes it even more insane. My idea is, since torque is the engines strong point, I want to do everything I can to bring more out.

So yea, lets hear your ideas/thoughts and I will share what ever I find on my journey!

The Real Dogman

Boom stick. Sounds alot like quest I was on last summer. however I wanted to keep the current suspension and looked at the exhaust configuration all together. I found that you are VERY right! The NX76 is very capable of producing insane torque when the restrictive OEM header is replaced with something more free flowing. I also wanted to get the oil off of the right rear suspension. I had great success with the exhaust dumping out he back using a homemade twin tip triple chamber homemade piece out of common copper tubing. The truck sounded mean as hell and had killer torque, However the first header I made from copper tubing failed very quickly because I forget that the typical plumbing solder melted @ typical exhaust temps. I then tried to modify an existing header by cutting and rotating it to go ver the shock tower into my triple chamber muffler. WOW what a blast that was everything worked so well I wanted to have that header made larger inside diameter or better flow. But no takers were to be found and due to extreme stress on the silicone coupler and other projects it is now currently sitting on a shelf waiting for me to come with a way to make my own header like the copper header.

here are some pics as well maybe a couple in my gallery

Boom_Stick

I remember when you posted that in the other thread. I bet you that made a difference you could feel for sure!


The reason why I am going this route is so that once I get something down thats working well, anyone can score some off the shelf parts and get it up and running. Thats one thing all genny owners suffer from is a major lack of exhaust options. If I can come up with a different suspension that keeps the truck running well with only 1 shock on the rear(each side), or maybe 2 just on the rear side of the tower, we will have a ton of different exhaust solutions that we can pick and choose from. Maybe even find that special combo that helps us unleash even more of the .46's insane power.

Has anyone tested/ran Savage shocks? They seem to be long enough, and pretty thin


PS> TRD, I suffered from the half-tank blues (or 1/4 tank) prior to my exhaust change, but since I changed over to this new setup I was running full tanks all day today with no stalls. Infact, I found myself wondering why my truck was still running after soo long! I know the OFNA filter seems to fix it for most people, but its nice that this exhaust change also brought another fix to light.

Scott_GTR

It may be an idea to look at fitting the large Losi dampers on the rear.
They obviously make a spring rate suitable for a single shock set up.

Boom_Stick

Thanks for the input Scott,

I got a couple of different springs in mind and maybe going to a 8.3lbs - 8.5lbs springs might be enough. If not, I may try out some LST or Savage suspensions.

http://www2.towerhobbies.com/cgi-bin...&I=LXHWJ7&P=ML

http://www2.towerhobbies.com/cgi-bin...?&I=LXLNV3&P=7

http://www2.towerhobbies.com/cgi-bin...?&I=LXFRC3&P=7


I figure I will try the above, and if they don't work/fit/etc I always have uses for springs

MONAROMAN

Yeah those Losi LST2 shocks are huge, I'm eyeing off my stock FG MT springs right now

So what pipe/header combo are you running now?

Boom_Stick

I started with this Dynamite combo http://www.dynamiterc.com/Products/D...rodID=DYNP5000

I picked it for two reasons, #1 It was cheap @ my LHS, and #2 the header would fit the space well. My intent is to get it rolling with a suspension that will function well, then try different pipe/header combos. Hopefully I get that tower order in this week or soon after so I can see what I can do to tighten up the rear.


Here is a pick with the exhaust just fitted on the truck. Before I took it out and tested it, I removed the other rear shock. (I ran with 2 shocks total on the rear (Both on the back side of the tower))

burningpoo

Let me know how that pipe works/sounds. That's the same one from the pic, right?

Boom_Stick

burningpoo,

Yea thats the same pipe from the pix. I don't want to recommend it until I find a proper suspension mod in the rear to keep the front wheel on the ground. Its hard to test the power when half of it is in the air [:'(]

I'm ordering the springs and a servo arm tonight in hopes that will cure it. I may even go with the LST shocks as mentioned earlier

burningpoo

if your getting extra power that's all i need to know, i'm ordering a GST in a week or 2, I'll learn to live with the front in the air[>:]

thanks

Boom_Stick

Well its like this,


With the shock mod and possiblely due to a little extra torque (I suspect 98% removal of shock and MAYBE 2% additional power related) I can't keep the wheels on the ground. That means all the power sent to the front wheels is wasted. When I mod the rear of the truck with a beefer suspension that enables me to run 1 shock on each side properly so that the truck support the Gs under acceleration, I will be in a better posistion to observe power gains. Right now its not the right time to look for that. I am sure there are power gains, because removing that constricting stock header could only help. The stock pipe is huge, so I suspect some weight savings there (Every little bit helps). I can say currently the truck runs better with the new exhaust. No 1/4 to 1/2 tank stall issues anymore. That tells me it provides more back pressure and it idles a touch smoother. I have seen longer runs, but I can't tell if thats because I am used the the 1/4 tank issues that seems to have cleared up with the new exhaust, or if the new exhaust extended the run time due to better fuel use.


This weekend I will be able to provide more feedback on the exhaust as I ordered every thing I wanted to try for the rear suspension. I decided to run some LST shocks on the rear (Thx to Scott_GTR for the input) with the most stiff spring I could find (8.3lbs). Once I get that fitted correctly I should be planting the power to the ground and will be able to correctly observe the trucks performance.


So hang in there and give me to the end of this weekend and I should have some good feedback for you, supported with some pics and a part list of what I used to do it

Boom_Stick

I doubt the LST shocks will fit [>:], I just got my LST springs in and they looked like a sleeve of girl scout cookies! I may have to build some custom towers in order to use them. I would be doing that now, but I bought another RC (Woot woot!). I just got an nice little entry level 1/8 buggy. Its an Ofna TQ Sport. I was trying to find a LHS that carried parts for the CEN buggies, but none did. Since I am going to race this on the weekends I had to go with one I had access to in-stock parts for. I just got about 3/4 down breaking it in, and I should be ready to tune before I head over to the track tomorrow to pull some laps before the "official" practice. There is another local track racing Sunday, so I plan to catch that. If I can't make it or don't feel like it I will more than likely get back to work on the GST suspension rig.

burningpoo

no mod's to make that exhaust fit?

The Real Dogman

Hey Boom, no offense intended but I'm glad you painted that hummer body when you were hammered. That thing is almost as hideous as my stock nemesis body, lol. gotta love the drunken dribbles, good stuff buddy..[8D][:'(] couldn't have done that sober!!! lol

Boom_Stick

burningpoo,

I am still working on the suspension in the back, I still hope to come up with something this weekend. If not a solution perhaps atleast another idea to move forward on. Even though I have the springs for the LST, I am still waiting for my shocks I purchased on ebay.

TRD,

Amen to the half-ass body jobs! I actually had my purple perl phade looking good until I started pulling tape to early. After that it went down hill, by that time I was pretty much as tanked as I was getting. The worst part is I had access to a drill at the time

burningpoo

How much shorter are the lst2 shocks? Are they to wide? I haven't seen the gst shocks but I thought they looked longer.

Boom_Stick

burningpoo,

I don't have the LST shocks in hand, but using the springs as an indicator, they a monsters. Maybe the same length as the GST but 1 lst shock is equal to the width of 2 GSTs.


On a side note, I had the 1st day blues today with the Ofna.

Heat 1
I didn't hear the start, so I was in last by turn one. Half way through the first lap I passed 2 people! About 3 or 4 mins into the 6min heat BOOM my steering servo went.

Heat 2
With 30 seconds to the start of the race I put my car down and got lined up. (After I swapped SS's for a Hitec 5995) by the time I was coming out of turn one, the hitec just stopped working.

Heat 3
Replaced the new hitec with another new hitec (Swap out w/ another new from the LHS), my main recv pack dies 2 laps in. So at this point I started to pack up and head home


NOTE: My genny never gave me this much hassle! I just wish my LHS's would have stocked CEN parts, I wouldn't be racing an Ofna

Boom_Stick

I got the LST shocks in my hand now. I have a race Sat so I will be practicing with the buggy this week to hopefuly get some skill down and earn some much needed points. I have a long weekend coming up here (Off Monday), so I think I will have sometime Monday to adapt the suspension or atleast design/find all the parts I will need to get it running.

Sorry its taking soo long guys but setting up a buggy for racing, working insane hours (yesterday was a light day @ 14hrs) and just some overall lazyness has drawn this out a little.


Anyways here is a pic of them to give you an idea of their size. These things are HUGE!

MONAROMAN

Those shocks are FAT! Can't wait to see em fitted and I hope they do the trick. I hear ya about the time tho. []

MONAROMAN

Sorry for double posting but I remember seeing this pic of LST shocks on an FG monster truck on another forum, although these have reservoirs like the CEN ones and I don't think this truck sees the dirt... at least I wouldn't dare!