back to nitro after 2 years ..

[harry118]

So after buying a hpi rs4 around 2-3years ago from a member form the site and not having much luck with it tuning wise I gave up and bought 2 hpi sprints lipos. 

 

After selling them about a year ago I'm missing the rc life and was looking at buying the hpi rs4 sport flux lipo 

 

But iv always had the thought I'm the back of my head about fixing/tuning my nitro again 

 

So Now iv got the itch again to get the nitro going so pulling it out and having it cleaned and hopfully start fresh again with a bit of luck I can get it set up and enjoy it as I should

 

[DBXL Smithy]

You should look up how to tune etc before deciding buying a new nitro. They are the pain in the back side and sometimes need re-tuning every 20 minutes or so otherwise you'll crack the cylinder if to hot etc. 

[spannermonkey]

I have dabbled with both brushless and nitro, always end up back with my nitros. Its a Marmite thing. A good nitro will hold a tune and only need minor tweaks day to day. If your not racing and bashing for fun running a little rich isnt going to hurt so no need to max performance tune every time out. In my opion they are no more faff than lipos, its a case of each to their own.

[harry118]

O  no I'm not buying a new nitro thus is my old one from years ago that I gave up on and got forgotten about for years lol.

 

Don't no why but just love the thought of a nitro running right For once. got so frustrated last time I packed it away.

 

Just looked online and found the factory needle setting to I'll give it ago after work.

 

Any one got any tips or advice for the hpi t3 engine ?

[tomr]

On 28 April 2016 at 19:39, DBXL Smithy said:

You should look up how to tune etc before deciding buying a new nitro. They are the pain in the back side and sometimes need re-tuning every 20 minutes or so otherwise you'll crack the cylinder if to hot etc. 

Once you start to understand nitro engines  tuning is easy and they do not need tuning every 20 mins lol 

[harry118]

Thanks tom after reading the msuk tuning guide I had a go last night and I could not believe it iv got it to run ??

The  idle seem to be very good the pick up seem to be perfect and even goes in to second gear.  ( I was running the lsn way too rich)

 

Done a full 2 tanks in it last nite.

 

Only issues I'm having is I tuned the lsn 1st then the hsn. Iv read it should be the other way round.

 

And if hit the throttle hard at top end speed the car cuts out. But if I hit the throttle smother to top speed it's fine ?

Any ideas 

 

Very nice satisfaction when things start working ?

[locky]

Only tune when engine thoroughly warm.

The low speed needle LSN is used to meter the fuel at idle and low RPM, the high speed needle HSN at moderate RPM to wide open throttle (WOT). The HSN is the first needle in the fuel supply, so adjusting this will have an effect on the fuel flow to the LSN, that's why it's recommended to adjust HSN first, but when tune is close to perfect then not so critical,

Richen HSN a little, 1/8 turn, repeat driving style. 

Does rpm hang after full throttle run or drop quickly to idle?

 

[Pistonhead]

Sounds like it's too lean on the top end. I like to put a full tank through my race engines before tuning, idling the buggy on the box for a few minutes with regular throttle blips and the odd full throttle rev to clear its throat, then a few laps of the track to get to stable running temp, refill then tune to suit conditions.

[harry118]

Thanks guys so I took it out again for a blast and and done the hsn a bit richer but it went worse it cut out just over half throttle so I went back set it 1-2 hours leaner the my original setting I started off with and runs fine now and changes in 2ed gear alot faster now too. 

 

 

Bad news while I was testing lost my spur gear  teeth are all worn out on 1 of the cogs ? so will have to order some new ones.

 

So it prob a good time for a full stip down and rebuild while I'm waiting for the parts. And to sort my brake out on the car too ?