Try the NR 9886 pipe with short 41021 short round pipe and hold on to your hat!!!

I have an 086 ofna pipe from a while back, I am running the 41021 header on the 9853 pipe. I will have to take your advice. I'm going to a big track this weekend, thus the new FMS. I mainly run p5's, but I wanted an engine for the larger tracks. I had the blue head 7 port nova and this engine looks similar, but it's way better. I've never heard an engine get on the pipe like the FMS besides a full mod whatever. As I was driving it. I thought, that's what I was looking for. I think the Toro Team might be awesome too if they really gave it more torque, but I didn't want to spend more than 300 bucks just to find out.

One tip: On the Novarossi engines like the plus-4, toro, and FMS, the front bearing is just .3mm wider, double sealed, so when installing the flywheel and clutch, the clutch bell sticks out a little farther and can make the spur ride on the inside of the clutch bell gear. I ground the tip of the clutch nut, the tapered part, just a tiny bit so you can still use at least one shim to protect the clutch bearings and maintain proper alignment. Every car is different, but it seems to happen more often than not. Just a thought........

One question. What after run oil is safe for the silicone ramp on the crank?

I use Marvel Mystery oil, but I'm not sure it's safe on the filled crank.....

Anyone try a 2084 on a P5?

I really thought the 9853 gave it more power, especially mid to top. Also, I thought my p5 got hotter with the 2084 than the 9853, extra baffle maybe. I returned it.....

Did you try the 9901 with the 021 header on the p5xlt??

One question. What after run oil is safe for the silicone ramp on the crank?

I use Marvel Mystery oil, but I'm not sure it's safe on the filled crank.....[/QUOTE]

Monty recommended me to RB mods oil and I have been using it for a few weeks on a HES P5 motor seams good

I use Marvel Mystery oil on my non-filled cranks and GMK on my filled cranks.
I heard MMO breaks down silicone. I also have a NR 367 and found that NR 7 port engines like cold plugs; try the OD99T when your break-in is complete.

U returned it ? Huh?

The whole reason they made the 2084ss is to provide more mileage to the 9853 pipe , it will get hotter , you will lean your needles out more to get speed out of it , you will get BETTER MILEAGE !

Monty recommended me to RB mods oil and I have been using it for a few weeks on a HES P5 motor seams good[/QUOTE]

Not marvels mystery oil

Rbmods ARO is killer

Hey Houston, do the Toro Neros have a Silicon Filled crank?

Thanks.

no , i do that and it improves throttle response quite a bit on the toro nero in particular

what plug are most people running on a plus4 turbo head ? I run the odonnell 97t but was told to go to a hotter plug ie 77t less chance of flame outs?

Depends on how much nitro you are running. A 97T, Novarossi C5 or C6 are great with 30% nitro. Use 77T or similar hot plugs with 25% nitro and 0,7 mm head shims.

If your plug is too cold, you'll have a hard time tuning the engine. With a warmed up engine, it sounds like it is running too rich on the HSN, when you goes to WOT on the starterbox. If you lean it until it runs clean, it will be waaay too lean on the track (perhaps 1/4 turn!!!!).
The idle is rotten. You'll have to lean it too much to have a rather stable idle but after WOT the engine doesn't come down to normal idlespeed for the first 5-10 seconds. After that it will but the engine will often stop.

yes that sounds like the problem i am having with 25% I will try the 77t and retune
thanks

I've never used a 9901 so I can't really say. I can say my two favorites are

9853ss great power overall.
9886 a bit more top end and smoother torque curve on a p5. Good on slipery tracks, or big tracks.

I do see lots of guys running the 9901 though....