Let us know how you go with the "head" tonight then
there is a very pretty girl coming out to spend a little time this evening so little to no work tonight.
New cylinder head project
Posted 24 May 2013 - 11:08 AM
Posted 24 May 2013 - 04:35 PM
She did help me go through the stash of bent files and cartridge rolls trying to find something to reach the last little bit of the short turn in the exhaust ports...there is a spot that I just can't get at yet and it's the last spot to do. After that, it's a little here, a little there, to get them all as close to identical as I can get them. (they're close, but they can get closer.) Port #1 was finished out completely, and match-up templates were made to make this job easier.
The intake ports, being round, are much easier for me; templates are simpler and there is less port re-shaping involved overall.
Exhaust ports will end up 30mm wide x 40mm tall, to match up with the header. Intakes are 38mm round; and I have 38mm templates made up from a past port job already, although they were for an E88 head...port is slightly different. P90 port is a slightly larger STR, and the valve guide bump is smaller.
The lower compression ratio from the larger volume will be most welcome; as going from a 42cc chamber to a 52cc chamber will drop me from 9.72:1 to 8.1:1...much more blower-friendly!
Posted 25 May 2013 - 09:14 PM
Posted 27 May 2013 - 12:33 PM
All the valves are machined, need to clean up the backs of the valves and oil them till I'm ready for them. Tomarrow is a trip to the shooting range, get to blow off some steam and relax. I shoot 400 and 600 yard target matches about three times a year; so the highly structured practice helps with relaxation.
Posted 30 May 2013 - 09:19 AM
His name is Jacek but people call him Jack, I remember (about 17 years ago). his engine was on the floor of Steve Newings shed and Sinisha's car was in there with L28 still in it .That yellow car was meant to be mine, I went to by the shell and an engine package from him, I made the mistake of getting excited about the rare shell and then he back flipped, kept the shell for himself and tried to tell me he was doing me a favor because it wasn't worth doing up. So I ended up with complete engine and drive line and nothing to put it in, man was I pissed!!! I remember him saying he would never put a G-nose on a Z, when I saw that autospeed article I thought
I can definitely confirm this, I know that engine went to a guy by the name of Jack Kuzior who I haven't seen or heard from in years now. I recall him talking about the custom head re-drilling and cooling mods due to cylinder #5 (my memory here) getting hot under the collar. The head was N42 casting.
This is the car the engine was in last I knew of.
Posted 05 June 2013 - 01:46 PM
Exhaust ports are finished, will get a final 120 grit finish before the flowbench and will get polished after. I have one intake port roughed in at 37mm, finished port will be 38mm.
Progression of an exhaust port:
Good shot of a finished port:
I swear this port isn't as wonky as it looks...the port floor is level with the deck surface. I went and checked twice after taking this photo.
Posted 05 June 2013 - 01:54 PM
Posted 05 June 2013 - 02:08 PM
Posted 05 June 2013 - 05:35 PM
Posted 06 June 2013 - 01:26 PM
I'm not THAT good...I don't get to do this every day. Every couple months I do a few single-cylinder and two cylinder engines, sometimes a set of VW heads. I have done datto heads a LOT, but it's a cut-and-try thing. As it is, I use templates to match the ports up as close as I can get them, but even then I have a long way to go before I can really skip a flow-check.
The exhaust ports I have pretty damn tightly matched, volume and shape wise. Each port matches the templates within 0.040", and that's just one port that is out that much...the rest are half that out. One of the combustion chambers has a small casting error, the exhaust valve seat is a little closer to the chamber wall than the others, and the intake is a little further away. Can't move them as much as I need to...the port wall would get into the valve seat area. I'd need to go to a slightly larger valve to get the seat pushed out enough. If this was a race car...I'd already have fixed the issue.
It's not a race car...it's my daily driver, that I've been without for nearly a month now. I'm getting impatient and it's getting harder to convince myself that close enough is not close enough.
Posted 15 June 2013 - 07:59 AM
I missed a buy of a 1976 Toyota RA22 Celica by fifteen minutes...the car sold for scrap metal to a dealer. I have called said dealer trying to throw money at him to get it before he crushes it.
BUT! I found a local flowbench and slapped the currently-37mm-ish ports on it, and did a little flow work! This is with what's left of the old valve job, on used, but clean, stock-sized valves. I lapped the valves in to get them to seal up closed, but that's about it. The top angle of the 3 angle job is still there, but a lot of the bottom angle isn't or is modified from the die grinder.
Lift - Intake Flow
.1 - 62.4
.2 - 117.1
.3 - 157.8
.4 - 199.1 (FIGJAM!)
.5 - 214.1
Lift - Exhaust flow
.1 -- 51.4
.2 -- 80.3
.3 -- 102.1
.4 -- 128.8
.5 -- 134.1
Not too bad! I have no idea how this compares to a stock port; as I don't have any heads with stock ports except a Maxima N47. I also have no idea if this bench is padded/accurate/garbage...it's an old garge-built unit that seemed pretty consistant, though. I was getting very close to the limits of the bench, I had the air valve wide open to get the full 28"WC for the upper end of the intake flow. A guy in the back of the neighborhood has it, but he's moving out this week. I saw it in his garage and asked if I could borrow it for a few minutes. An hour later, I was done and helped him load it into his moving truck.
I asked...he didn't want to sell. I have a very good idea of how to copy it though...
Posted 19 June 2013 - 10:35 AM
That's a finished intake port, The flow at 37mm was good enough that I blended the roof and sides into the 38mm intake manifold and called it done. The head goes to the machine shop for a proper valve job, S3S, and a second pressure test to make sure this one isn't cracked or ported badly...It happens.
Posted 21 August 2013 - 01:24 PM
After about a month, I'll get the super back on and we'll go see how the cool September air treats this dogged out transmission before I swap in the beefed up FS5W71E still sitting in my garage floor.
Posted 22 August 2013 - 11:29 AM
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