Budget 100x71 Build

This is the place to discuss, or get help with any of your Type 4 questions.
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cal 67
Posts: 271
Joined: Wed Apr 08, 2009 7:03 pm

Re: Budget 100x71 Build

Post by cal 67 » Thu Feb 04, 2021 3:35 pm

Finally ordered the new vents. I was going to machine my own, but I'd only be shaping them based on a hunch. Maybe I'll still do them and compare.

Made some chamber volume plates. I knocked out a few for the future. My 66x105 will need one, and I made one for the 36hp platform.

Sent these bad boys out to a 914 owner in Florida: Chromoly shafts, high strength 8mm studs, machined and resurfaced rockers, tool steel adjusters, spring steel shim varieties, pinned solid spacers, and narrowed mounting blocks.

A friend sent me these oversized shafts (left) as a gift for worn rockers. You can hone them and still be within radial spec. Centerless-ground, smaller mounting holes. The right ones are standard chromoly shafts.

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Eddie010
Posts: 141
Joined: Sat Dec 19, 2009 4:27 am

Re: Budget 100x71 Build

Post by Eddie010 » Fri Feb 05, 2021 2:54 am

Nice stuff.
Can I ask you a question, do you lock the spacer ring on the rockers?
Looks like you have bolts to hold them in place. Any reason for that?

Keep the pictures going, love your build.

This was a life saver for me, did not think of checking this.
Building a type 4 for the first time with Type 1 lifters.
cal 67 wrote:
Thu Jan 21, 2021 12:49 am
Check Everything! The #4 exhaust lifter hanging up on a casting bump after the thrust bearing:

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Did some quick filing, and got some needed clearance. I'll do more later. Just need to do cam timing and see where my decks are.

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cal 67
Posts: 271
Joined: Wed Apr 08, 2009 7:03 pm

Re: Budget 100x71 Build

Post by cal 67 » Fri Feb 05, 2021 10:39 am

Eddie010 wrote:
Fri Feb 05, 2021 2:54 am
Nice stuff.
Can I ask you a question, do you lock the spacer ring on the rockers?
Looks like you have bolts to hold them in place. Any reason for that?
Yes, they get locked. When the left rocker opens the valve, it's forced over onto the left rocker. The primary thrusts on these are on the right, whereas only the right rocker sees thrust load on both ends because of the left one is always pushing on it. This might be the reason for the stock center spring.

Anyway, pinning the center spacer separates the loading. I resurface the ends before shipping, and with the shims in place, I doubt they'll ever need resurfacing again.

cal 67
Posts: 271
Joined: Wed Apr 08, 2009 7:03 pm

Re: Budget 100x71 Build

Post by cal 67 » Mon Feb 08, 2021 12:51 am

I found someone to print me a balancing jig. 22 and 24 small ends, and Honda, Chevy, VW, and 2.0 big ends. Now just to figure how to get consistent readings...

Valve locks finally showed in two different heights to dial-in install height. I wanted titanium locks, but for this budgeted build, I thought I'd take it easy. These were half the price. Using titanium retainers though.

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cal 67
Posts: 271
Joined: Wed Apr 08, 2009 7:03 pm

Re: Budget 100x71 Build

Post by cal 67 » Thu Feb 11, 2021 6:32 pm

Finally started. I was looking over my work after, and I think I want to do a little more to the fins.

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cal 67
Posts: 271
Joined: Wed Apr 08, 2009 7:03 pm

Re: Budget 100x71 Build

Post by cal 67 » Tue Feb 23, 2021 12:09 pm

Heads are all welded and surfaced. I opted for Moldstar 90 seats. There's a guy on Ebay that'll cut whatever you want for a decent price. I requested that the seats be on the small side in the I.D. so I can finish them by hand. So I have dummy guides. Those get loosely pressed in, seats installed, then the guides get pushed back out for porting. When I'm all done, I'll install guides with the correct interference, ream, and perform the valve job. Unlike steel, these Moldstars only get about .006" interference fit.

Stock 40mm vents out, 44s in

Barrels got trimmed .180" to get .040" deck, and .050" positive deck at the dome center.

The Q cam is coming out (left), and the P is going in. I machined the cam again to clear the #2 exhaust lifter, and polished the thrusts a bit.

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cal 67
Posts: 271
Joined: Wed Apr 08, 2009 7:03 pm

Re: Budget 100x71 Build

Post by cal 67 » Thu Feb 25, 2021 12:59 pm

I found a local speed shop that does Moldstar 90 seats for a decent price - $22.50 each. The benefits outweigh the cost. The seats expand more uniformly with the head, so you run less interference fit, which might prevent the typical cracking that we see. Also,it should quiet down valvetrain noise.It was literally a last-minute decision to use them. He called to say he finished them last night. They should be in the head by next week.

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.180" trimmed off the bases and I still have .050" deck! I don't know where I messed up, but I need to trim another .005-.008" to get where I want to be.

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Heads awaiting seats and porting:

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