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see post #1.

i guess i forgot to post this:
i digested alot of info pretty fast here and forgot that part. that said, is this your goal with the supercharger or will you likely lower that to compensate for boost? i'm staying naturally aspirated fo now.
 

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turd-polish-a-go-go
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Discussion Starter #62
i digested alot of info pretty fast here and forgot that part. that said, is this your goal with the supercharger or will you likely lower that to compensate for boost? i'm staying naturally aspirated fo now.
i'm pushing the CR up to the limit that i can run on premium, then using engine management hardware to map fuel and timing and trimming it all off with knock-sensing, so the engine will run at max efficiency every single cylinder firing event. basically running the engine to its thermodynamic maximum, then perfecting fuel and spark to get the most energy possible out of it.
 

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thanks for the info, i start tear down on one of the spare motors this week. can't wait to get to port the head, haven't done one in a few years.
oh yeah, ShuDuk's avatar kicks ass, always cracks me up :laughing:
 

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turd-polish-a-go-go
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Discussion Starter #65
I love good tech :smokin: What octane level is "premium" in the states BTW ?
premium rates a measly 91 octane, about the same as cat pee. we can't tweak that, but we can tweak camming, ignition, flame front propagation, air flow, and fuel metering... wideband O2, knock sensing, crank trigger wheels, and MegaSquirt-II will bring me as close to the bleeding edge as possible. that's what we've got to work with.
 

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premium rates a measly 91 octane, about the same as cat pee. we can't tweak that, but we can tweak camming, ignition, flame front propagation, air flow, and fuel metering... wideband O2, knock sensing, crank trigger wheels, and MegaSquirt-II will bring me as close to the bleeding edge as possible. that's what we've got to work with.
91 octane huh, never ran that low octane before. Tried 92 but it sucked:evil: usually run 95 or 98 octane. I need to school myself(google) on tweak differences with various octane




oh yeah, ShuDuk's avatar kicks ass, always cracks me up :laughing:
me too :laughing:
 

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turd-polish-a-go-go
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Discussion Starter #68
91 octane huh, never ran that low octane before. Tried 92 but it sucked:evil: usually run 95 or 98 octane. I need to school myself(google) on tweak differences with various octane
US and EU use different systems for octane rating, forgot to mention that. our 91 octane is your 95 octane rated fuel. we can get better fuel at some pumps, or even leaded fuel at petroleum suppliers, but that shit gets expensive. anything other than 91 (U.S.) unleaded is too much trouble. i want to be able to fill 'er up anywhere i go, any time, so compression ratios and boost need to be held to that fuel. that's the #1 big reason for NOT running propane (#2 reason is you can't siphon propane into a coffee can from your buddy's rig so you can make it to the nearest filling station).
 

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turd-polish-a-go-go
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Discussion Starter #71
how do you go around the valveguides?? removed them prior to the port grinding?
yes, they must be pressed out before porting and replaced with new ones afterward. when replacing valve guides, the seats *must* be re-ground. valve seat concentricity must be matched to the bore centerlines of the new guides. guides are cheap at parts dinosaur (link). generally, the head needs to be heated when replacing guides. not a bad idea to resurface afterward for a better head gasket seal and a little bump in compression.
 

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finished my porting a week ago, head and block are at the machinist.:) also waiting on my cam from colt cams. both should be ready in a few weeks. i am real anxious to compare this little wonder to my current turd motor. thanks once again L B S.
 

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i'm pushing the CR up to the limit that i can run on premium, then using engine management hardware to map fuel and timing and trimming it all off with knock-sensing, so the engine will run at max efficiency every single cylinder firing event. basically running the engine to its thermodynamic maximum, then perfecting fuel and spark to get the most energy possible out of it.
Nice write up. I went through the about same build on my 1.3 back in 2000. But, without the write-up you did. Mainly because I knew not of Pirate 4x4 back then.

Now, when will you get it on a chassis dyno for the tuning if I may ask? It makes cam timing, ignition timing, spark plug orientation and fuel/air tuning much safer and quicker.
 

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turd-polish-a-go-go
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Discussion Starter #74
finished my porting a week ago, head and block are at the machinist.:) also waiting on my cam from colt cams. both should be ready in a few weeks. i am real anxious to compare this little wonder to my current turd motor. thanks once again L B S.
put up a post when it's ready!

Now, when will you get it on a chassis dyno for the tuning if I may ask? It makes cam timing, ignition timing, spark plug orientation and fuel/air tuning much safer and quicker.
thanks. i've been under the soldering iron for the last couple of days. i still have to work out a knock sensing circuit conditioner, but had to set up my tablet pc as an oscilloscope first. once this is done, it will be easy to replicate. as far as tuning, i will be relying on feedback data logging. i do have an accelerometer if i really want to get into turning ET's, but i am mainly interested in honing VE and timing. i know mallory has a chassis dyno in carson city, but i haven't considered the cost factor of dynamometer testing. of course, i'm sure y'all want numbers...
 

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put up a post when it's ready
will do. i will try to photo my ports too. they look pretty good for a non pro job. i tried to keep everything as uniform as possible, volume and profiles both. sometimes it's good to have a background in art and gunsmithing when you're doing stuff by the eye.
 

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turd-polish-a-go-go
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Discussion Starter #76
i tried to keep everything as uniform as possible, volume and profiles both.
yes, yes- i forgot to point out the way to keep volume straight. using internal dividers set to finished port width is a good way to maintain contour and volume, they will make tight spots easy to find and prevent overgrinding.

the tools:


the technique:
 

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Hi; Got anything on combustion chamber work? Such as in./ex. valve deshrouding.
Or what angle cuts to use on the valve an valve seat, or are you useing
insert cuters? This has been a great write up, thanks!
 

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hey just a quick question you seem to know basically everything about these engines!!

I have found in my research there are many differnt model numbers.. the G13, G13A, G13AB, G13K

My question is i have the G13 its from an 88 sammy, would pistons and rings and such work from the G13A/AB?? seeing as its from a year or 2 newer motor but all the google searching i have done shows the same bore stroke for those years, its up in the 90's when stuff started changing?

thanks sorry for getting off topic!
 

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turd-polish-a-go-go
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Discussion Starter #79
@SamyGuy: use the factory valve grind. unless somebody gets real serious with experimentation on a flow bench with this particular head, put faith in the engineers who designed it. i have a cylinder head book (one of many) where the british authors did an experiment with vauxall aluminum 4-banger heads and performed a progressive series of back cuts on the valve while measuring flow at each step at various lift increments. it is hard to say how modifications on one head design translate to another, but from what i could gain from that reading was that the suzuki design on valve profile is a pretty good one. the intake is fairly flat across the back, and the exhaust is trumpeted. with the cross-sectional area of the ports matching the valve area pretty well, and having a relatively high port ceiling (compared to iron V8's) that's the right combo. as far as chamber work, the main thing is to deshroud the intake near the cylinder wall, and blend the transition area away from the valve seat. there is a little "diamond" between the valves, that could be a potential hot spot and can be smoothed gently with an abrasive roll. use old rolls when doing combustion chambers, they work slower and leave a smoother finish. make sure there are no hot spots where the metal is thin around the spark plug threads as they enter the chamber. some folks polish combustion chambers, that was the thing to do back in the day. old school hot rodders would get away with an additional half point of compression on pump gas with polished chambers, which reflect heat inward (think of a mirror reflecting the sun on a hot day- reflects some heat). today, conventional wisdom is to bead blast the chambers to promote an ultrafine layer of carbon buildup. molecular carbon is an awesome insulator, and does more to contain heat than polishing. you want to get that heat out with the exhaust, not let it soak into the head.

@chev-head: the G-series are all dimensionally the same within their respective size categories. difference is carb, tbi, and 16v mpfi. you need to get the piston kit that matches the head you are using, 8v or 16v. there is a sticky on teamswift.net that covers the G-series alphanumeric designations for more info.
 
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