Thread: 355 combo evaluation -dyno? Thoughts, suggestions, comments appreciated

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Looks like a great build to me. 5.13 with 37" tire will be the same relationship as 3.54 with a 26" tire. I might have gone with 5.38 gears, but you're close.

I would not have used 1.6 rockers in anything but a race motor build, where routine maintenance is practiced. In my opinion, the valvetrain already has enough strain on it without the added strain of higher ratio rockers, particularly with aftermarket springs. They're probably worth only about 10-12 horsepower over 1.5's anyway. I'd use 'em only if I needed extra power to drive around a competitor in structured class racing.

Cam appears to be a very good match and the 112 LSA should help produce sufficient vacuum for power brakes. it should begin making power somewhere around 2000, so a 10", 2500/2800 stall converter might be my choice. Choose a small 10" diameter unit that is designed from the git-go for the purpose, rather than a 12" unit with the fins bent over.

Squish/quench is right on the money at 0.041".

Install an H pipe immediately after the collectors for better sound and a slight increase in power. The motor will like a good balance side to side.

Sorry, I know nothing at all about EFI, but maybe one of the other fellows on the board will chip in.

Some pics would be appreciated.
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Techinspector:
Thank you for the feedback. I have thought about trading my 1.6 Scorpion rockers for some 1.5's just to simmer down the wear on valve train components. Maybe someone here has an interest to trade. I just dont want to trade new for used. In the past few years of the gathering of parts and such I have read a bit on the wear aspect (after I bought them of corse...). Prior I was all about the free horsepower.

You are spot on for torque converter selection as my research from Coan, Yank and TCI. Ok, here is my dillema. One of the use conditions in my rig is downhill slow speed. I have been in situations were braking is not really ideal. Rather idle down in gear. My fear is that a converter more than a few hundred RPM over stock will suck. In addition some obsticles up hill would be best navigated with the same type of low stall converter. My thought is that if the dyno numbers are close enough to make power at the lower rpm I could sacrifice the ideal stall speed for a lower stall.

DO you think this engine would make reasonable power down low to justify the lower stall. Note I have the th350 built with a Transgo kit to hold 1st and 2nd while full auto in 3rd.

Originally Posted by techinspector1

Some pics would be appreciated.
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Took 2 degrees advance to get it dialed in to the cam card at 106...
https://imgur.com/5o6rE83