OS R21 .21 1/8 On-road Motor
#121

Hi ByronF1,
Which pipe and header you are running on your R21 / SRX8TQ?
I run same chassis & I've so far tested the R21 with Hipex S48 manifold and 2108 pipe, 19/24 pinions and 58/63 spurs. Felt very strong low end, and very smooth transition but not a super high rpm. I didn't do a timed run to check fuel consumption. I'd dare say this combo will do 7 minutes comfortably. I'm planning to try the NR 41032 manifold and different pipes on it soon.
Which pipe and header you are running on your R21 / SRX8TQ?
I run same chassis & I've so far tested the R21 with Hipex S48 manifold and 2108 pipe, 19/24 pinions and 58/63 spurs. Felt very strong low end, and very smooth transition but not a super high rpm. I didn't do a timed run to check fuel consumption. I'd dare say this combo will do 7 minutes comfortably. I'm planning to try the NR 41032 manifold and different pipes on it soon.
I changed the carburator because I felt the original the setting of the needles was so loose, I put a old carburator from another engine I broke was PoweMax 2015 21GT, and also change the cooling head from ONE motoros for the R21. Same Pinions 57/62 spur. I think for the consumption the clutch has to be fine, and the combo for header/pipe.
The OS GT Combo I saw in our track > 8min almost 9, but it is little slow
#122

Does anyone have experience with the new Hasi R21 7 port?