Expiremental OM617 build
Expiremental OM617 build
![[Image: IMG_20160927_183516_zpst1ritc36.jpg]](http://i346.photobucket.com/albums/p435/R-3350/IMG_20160927_183516_zpst1ritc36.jpg)
" />the head has been ported as far as i am comfortable with for now. the short side radius on the stock ports is atrocious, also the intake runners decline into the valve while the exhaust is almost a direct 90 degree turn. i contemplated reshaping the chambers and valve reliefs to help reduce valve shrouding but without a flow bench and a few spare heads to play with thats a dangerous move.[img]<a href=[/img]
![[Image: IMG_20160924_165949_zpsiyfjcwrk.jpg]](http://i346.photobucket.com/albums/p435/R-3350/IMG_20160924_165949_zpsiyfjcwrk.jpg)
" /> i talked to Geoff at Colt cams about a bigger cam to go with the better head flow. He said they have a few profiles for the OM617 that are good for a little more flow without hurting the low down power, so ill be ordering one as soon as budget allows. he also was interested in creating something more extreme when i mentioned the ported head and the other work i have been doing. so maybe once this car is no longer a daily ill look into going a bit farther. i am currently tearing the short block down to see what needs replacing while also getting some ideas for other things to tinker with. something that interested me was the timing advance mechanism, according to the FSM the early models prior to 1980 have 8 degrees of advance while the later have 7.5. i am considering grinding the stops to allow another 1-2 degrees of advance. this should hopefully help increase the usable power band a bit as even if you tinker with the high idle governor it still falls on its face above 5K.Sorry for the rambling i genuinely enjoy testing ideas and seeing what sticks. if anyone has had any similar ideas feel free to chip in im game.
the car has been doing well with the new turbo. it maxes out at 17 psi right now however it doesn't like to make more than 10 psi below 3000 RPM. i would like to drop that to 15 but as it is i think its leaking drive pressure from the WG due to reducing the WG spring pressure too much. i might try feeding it vacuum with a manual boost controller to feed pressure once the set point is reached. ill have to see if that helps. in other news i picked up a new short block to go with the head i have been doing a lot of work to.[img]<a href=[/img]" />
the head has been ported as far as i am comfortable with for now. the short side radius on the stock ports is atrocious, also the intake runners decline into the valve while the exhaust is almost a direct 90 degree turn. i contemplated reshaping the chambers and valve reliefs to help reduce valve shrouding but without a flow bench and a few spare heads to play with thats a dangerous move.[img]<a href=[/img]" /> i talked to Geoff at Colt cams about a bigger cam to go with the better head flow. He said they have a few profiles for the OM617 that are good for a little more flow without hurting the low down power, so ill be ordering one as soon as budget allows. he also was interested in creating something more extreme when i mentioned the ported head and the other work i have been doing. so maybe once this car is no longer a daily ill look into going a bit farther. i am currently tearing the short block down to see what needs replacing while also getting some ideas for other things to tinker with. something that interested me was the timing advance mechanism, according to the FSM the early models prior to 1980 have 8 degrees of advance while the later have 7.5. i am considering grinding the stops to allow another 1-2 degrees of advance. this should hopefully help increase the usable power band a bit as even if you tinker with the high idle governor it still falls on its face above 5K.
Sorry for the rambling i genuinely enjoy testing ideas and seeing what sticks. if anyone has had any similar ideas feel free to chip in im game.
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