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Inexpensive motor build part 1

36910 Views 150 Replies 74 Participants Last post by  NX$paniard
8
So my pet project is to attempt to bust 200 whp with a very simple easy and cheap to duplicate motor. I figure that this motor eliminates most of the expensive parts of an engine build and any dork can do this sort of build, well maybe not total "special people" but anyone of reasonable means and intellegence should be able to easily duplicate this if they live near in any major city. This should also be a very reliable motor as well.

Pistons



Cheapo SR16VE pistons, straight from Greg V. I think these suckers were about a whooping 40 bucks each or something. They are the lightest of the high comp SR pistons so they are easy on the pin boss due to lower inertial loading, unlike my ill fated VG pistons. They use the thin low tension 2000-2002 roller motor rings so high rpm ring seal should prove better, this was a problem with the thick ring VG piston. The dome and compression ring lands are hard anodized from the factorywhich is cool. Cast pistons, although not as tough as forged costly parts run much tighter clearance and are more dimentionaly stable as well as softer. This means longer life when it comes to daily driving or track useage. Just don't detonate them hard.

I had the pistons flycut 1mm for more valve clearance in case I want to run tight lobe centers and swain gold TCB coated on the dome with PC9 on the skirts. This is Swains harder thicker skirt coating. The PC9 tigtens clearances in the used STD bore block to like factory fresh, which saves on machining. To hone or bore an SR block, you really need a deck plate and an old bellhousing to machine an SR correctly as the SR blocks bores distorts badly with head bolt torque. Hardly any machine shops outside of JWT and a few other places have SR20 deck plates.

I just used a dingle ball hone to deglaze and clean the bore up and finished that surface with a few strokes of a cork bond platue hone. These pistons ends up being about 11.5:1 with flycutting and valve unshrouding. I think they were 40 grams or something lighter than stock.

Rods



Eagle rods. I can't belive they are this cheap and well made. I have Carrillos and Crowers for other projects and the machining quality seems to be better with these. Ligher than stock by about 100 grams. Full circle forged on the big end, shot peened, SPS bolts and other details. The raw forging is made in china but the materials and finish machining are done here.

Windage tray and scraper




Gets rid of the power robbing, oil consuming, heat producing windage cloud and puts the oil back to pan quicker hopefuly. Free cheap power and reliabilty.

Block mods



DET oil squirters and GTI-R N-1 style main saddle grooving for improved rod bearing oil feed.

Bearings



Calico coated clevite DET main bearings. See the extra oil feed holes? Remember the grooved main saddles? Ah now you understand the better oil feed for the rod bearings.

Crank



Knife edged and lightend for less windage losses. Balanced but otherwise not too molested. This sort of machine work is cheap around my parts. Took off a lb of material from the crank, equal to the amount taken off the rods and pistons. Could have went a lot more but it would have cost more and have more unbalance.

Head



Headwork is usualy the most expensive part of a motorbuild. I wanted to see what a home port job could do. Deburing and knocking the rough parts out of the combustion chamber, not even polishing. Good 3 angle valve job, slight effort at matching the seats to the head casting and a little short side radius work. Anyone with a compressor and die grinder could do this in the garage at home in an evening. The valves were unshrouded to the gasket line as well. I mean its really just a clean up extension of the valve job.

The rest of the motor is stock with the exeception of the C3 cams (wanted to do an easy to set up and maintain valvetrain although I do have C6M's as well). JWT valve springs and timing gears and a Chuck header.

One thing I am trying is the WPC process. This is bombarding parts with tiny ceramic balls at hypersonic speeds with the addtion of moly and zinc powder. Improves fatiuge strength like shotpeening but leaves a super smooth lubricous surface.

Did it to cylinder walls, rings, cam lobes, rockers, crank and oil pump. Last motor I did it to turns over super easy and idles real smooth even with C3 cams. No dyno yet. My Cosworth buddies swear by this process.

This motor is cheap but with a lot of attention to details and assembly accuracy. I hope this combo makes at least 180 whp.
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I don't know about 200whp but cool post. I would be interested to see how this compares to a stock ve since you would be approaching that price point.
Very interesting... Is this for your green car?
I don't know about 200whp but cool post. I would be interested to see how this compares to a stock ve since you would be approaching that price point.
Dunno, you could probably build this for under $1000 if you don't count the cams. I have way less than that into it.

I liked my DE a lot before it blew up, it had more torque down low than my VE. The only thing was a really rocking raced out idle which was annoying for driving around town.

The VE is better at idle and at real low revs like under 3000 rpm.

A properly built DE is no slouch and is probably cheaper.

I am going to compare this to my all out VE which is also getting built soon.
Very interesting... Is this for your green car?
Yes to replace the motor that really blew up. Once my VE is built i'll probably sell this motor. I am screwing around to see how much power I can get for the least amount of money.
I'm subscribing to this. I'd like to see how well this motor will perform. Good luck Mike....I'll be watching.
WPC treatment ?
how much it cost ?

i know in japan
people normally do WPC treatment for chocolate gearbox like RNN14 gearbox
Mike...can you tell Howard when you see him what needs to be done with my block...looks like this is the route to go.
subscribed
not many people know what the clearance piston to valve is like,
Any chance you could see how close the sr16ve pistons are to the valve.
I know your going c3 cams which are larger then my procams 12.5mm lift, but if you could work out a rough guess that would be great!
Nice will be following up on this project as I am thinking about doing an all motor build for a beater I am getting.
looks like a fun cheap set up. who makes that windage tray?
looks like a fun cheap set up. who makes that windage tray?
ditto very interested in this, would it be possible to do a total tally of money spent?
Mike - thanks for sharing this build with the forum...


looks like a fun cheap set up. who makes that windage tray?
Thats a newer version of one that's been shown on this site a few times... it's a Ishihara-Johnson crank scraper and windage tray. I actually installed his first one, designed for a DE, a few years back in my Avenir motor...
Mike...can you tell Howard when you see him what needs to be done with my block...looks like this is the route to go.
I don't think you want to spend the money. It cost more than everything else put together. I just did it to gain experiance using the process. I am mostly interested in seeing if it helps durabilty.
ditto very interested in this, would it be possible to do a total tally of money spent?
I am sorta guessing at the street price as i buy things at special spnsered racer prices. Pistons around $240, rods around $ 350, crank machining, $200 (not really needed), crank scraper stuff $200, bearings $250. The rest of the stuff was labor.

The block grooving was done with a cutoff wheel with a simple home made jig guide.
looks like a fun cheap set up. who makes that windage tray?
Its from Ishiwata-Johnson www.crank-scraper.com
WPC treatment ?
how much it cost ?

i know in japan
people normally do WPC treatment for chocolate gearbox like RNN14 gearbox
what is a chocolate gearbox? http://www.wpctreatment.com/
not to get too far off topic but any reason you didnt use a 4crw crank.
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