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Old 08-24-2019, 06:25 AM
onionfmr onionfmr is offline
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Default Trailmaster MB200-2 Engine RPM, TAV & Gearing

Looking for some advice, pointing in a direction. I've been working on this build for approximately a year. Getting close, but kind of hit a wall in terms of performance. Here's the general information of the build:
Tillotson 212 Hemi.
Billet flywheel and rod.
.010 head gasket.
CS 265 cam, 7000 max RPM.
26# valve springs.
Mikuni VM22-133 with 20 pilot and 140 main jets.
Chinese TAV with 146 gram weights, white garter springs. Driven spring in 3rd hole.
10 tooth jackshaft sprocket and 50 tooth rear sprocket.

Engine will hit a top RPM now of 5,500 RPMs at full throttle and then fall back to around 5,200 RPMs if the throttle is help open. Top speed at approximately 550 feet on a GPS is 45 MPH. RPMs top at 5,500. That's it. I'm guessing that I might pick up a little RPMs and top speed if I held the throttle open over a longer distance. Based on the feel of the engine, it isn't pulling hard at this point. Kind of flat.

I would like increase my top speed to around 51 MPH over this distance. I'm thinking of changing to the blue/silver garter springs and to yellow spring in the driven unit. Realizing that I can change gearing to accomplish more top end, but will lose on the low end. I would like to get more RPM out of this engine maintaining my existing gearing. Here's the question. Would swapping to a different cam, head work, etc.., allow me to build more RPMs or am I stuck because of the TAV and the gearing and need to change gearing (60 tooth rear sprocket) to get more out of this engine package? Thanks in advance for any comments and suggestions.

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