Tire Shredder's MK2 7MGE budget NA screamer build thread

[Tire Shredder]

my bad, maybe I should clarify...this motor will never see boost. The motor that does see boost may not even be a 7m, and if it is, it will be a later 7mgte block, with piston cooling nozzles, lower compression (perhaps forged), with full GTE electronics. This is an NA motor, and will stay that way until removed.

 

[WoundLicker]

I must say i like your intellect and your ideals upon your build.

I've been eying a Mk2 thats been sitting idle and this thread is making me think it would be a fun option.

Love your ride.

 

[bowsercake]

I'd love to have a MKII as clean as yours. It is SO nice!

 

[Tire Shredder]

quick, and boring update:

I borrowed an air compressor and die grinder from George (Raptor Racing), which is now in my basement. I ordered a head porting kit from standard abrassives. found here:
http://standardabrasives.carshopinc.com/product_info.php/products_id/52221/260001
(actually got my kit from ebay)

this is the article that inspired me to purchase it: http://www.sa-motorsports.com/diyport.aspx

origonal information found on wesley hetrick's mk2 head rebuild found here. http://www.tscperformance.com/cylinder_home.html

I expect to have the tools and gasket set in my hands this friday. I need to grab the cams from my parents house so I can send the head for cleaning and inspection, then the porting work begins (expect lots of pics!).

I'm excited to have bought some parts!

 

[Tire Shredder]

update on the engine! I recieved the head back from the machine shop. I had it cleaned, pressure tested and checked for warpage. Everything looks good, there are no cracks and it's warped 8 thousandths. I will have it machined flat after the porting and hand lapping is done.

the new engine gasket set from ebay, $80! and the stripped valve covers. I just started sanding, going smoothly so far. The gaskets look very good in this sit but the headgasket looks like garbage it's like made of paper, and the two layers don't line up properly. My plan for using a stock headgasket hinged on this being decent. This won't do. most of you will be happy to hear I will be buying a MHG.

Reground valves (Thanks DJ!!!). thinking about throwing these in and hand lapping the valves to save some money...no proper valve job. Thoughts???

The standard abrasives porting kit.

it comes with a nice fold out of instructions, like their online tutorial.

The head degreased and inspected, looks good! I'm not happy with the cleaning job but I instructed him not to glass bead it, I didn't want to run the rist of getting beads in the passages. I'll clean it up as best I can myself. I thought it would be a waste spending a ton of time cleaning it since I will have to clean it again once the porting, valve seating and resurfacing is done, at least I can handle it now!

I'm going to make these smoother

under the head.

The camshafts look good all cleaned up. I have since sprayed them down with WD-40. they will get polished to remove any surface rust.

The first journal on this one is questionable, definate scoring on it, I will attempt to polish them out somewhat, opinions (sorry for the horrible pic)

That's it for now guys, I'm going to go downstairs and start my porting work...hopefully it goes smoothly!! any tips, suggestions or comments are welcome about anything...specifically the thought of hand lapping and the scoring issue on that camshaft journal.

Steve

 

[Tire Shredder]

here's some pics of my brake upgrade using cressida brakes. KVR "carbon fibre" brake pads were used with a new toyota fitting kit, KVR slotted and plated rotors were installed along wit technafit stainless braided lines. I used rebuilt calipers in the front and cleaned and greased the rear supra calipers (all new KVR stuff there too). The rotors are 12mm larger diameter and 2mm thicker than supra rotors, so the calipers had to be ground to clear the wheels. Somebody may run a search for this at some point...so I thought I'd post it up. Hey, it's a build thread right?

here you can see the clearance issues

This is where it rubs on the rim, that silver line where there isn't brake dust

This is where it needs to be ground...the large area. the front doesn't, I just smoothed it out for looks. This is the first step of grinding, it needs to be done more.

after being ground enough, we've got some clearance

This is what my grinding looked like when finished, it's ready for paint now.

all painted, looking good (the front at least)

I wasn't smart enough to take any assembled pics...but that's not the important part, it looks good and stops excellently, George can attest to that now

 

[Tire Shredder]

Remember when I said this was a budget build? I wasn't kidding.

How to build a work bench
Step 1: find a garbage can, empty it.

Step 2: safety first! fill it full of supra rims (or bricks...but supra rims are more appropriate I think) so it won't tip over!

Step 3: Find some left over plywood from your home's construction and lay on top. Finish it off with a stolen hotel towel to prevent head surface from gouge's.

voila! free work table haha!

you laugh? good.


anyways, onto more important things...

port matching the intake side. Colour it with a sharpie and score it with a scribe.

there isn't much to remove here, just smooth out that little lip and remove a bit of material.

right is done with 40 grit, left is done with 80 grit, just a little more touch up left on it before I can move on.

just to double check, I put the gasket on again, no green showing through! good!

so far this has gone very smoothly, and much easier than I had thought. All you have to do is take your time. I'm amazed at toyota's casting quality. the gaskets are very close matched and there are no ridges. They look nothing like the domestic head's I've seen.

That's it for now, more pics as I make more progress. Thoughts and comments welcome as usual! Steve

 

[Tire Shredder]

most carb related porting guides suggest an 80 grit final finish. However, I have heard on line for fuel injected motors, 120 grit is a much better choice. Can somebody more knowledgeable than me suggest something?

 

[Yotaholic]

Lookin good Steve and I'm enjoying seeing your progress keep up the excellent work . Good tip on the brakes :icon_bigg

oh IMO I would go with the 120 or finer . Smoother the better !!

 

[SupaMan]

im enjoying this build alot i like to see people doing it themselfs it makes me wanna try it

*goes to find complete spare 7m head from old maroon car*:evil2:

 

[Poodles]

a product called chem dip will clean the head VERY well, but takes a hell of a long time and smells like fermaldahyde... on your head it's mostly clean, so it shouldn't take too long and it left the head shiney when done (only did half of my head before it went to machine shop)

machine shop bead blasted my head, leaves the very good toyota casting dull and ugly... won't ever do it again...

 

[Mr.PFloyd]

STEVE! See you at the next meet. also, if you want some stock turbo 7m stuff, lmk, i need space in my garage lol.

 

[honestabe]

Wow that is a clean MKII. Can't wait to see it done.

 

[Tire Shredder]

time for a quick update and a question!

I've finally found some time to get some work done. The intake manifold and throttle body are port matched and the intake side of the head has come a long way too.

Sitting in my thermodynamics class, discussing the efficiency of turbine engines, I thought about reducing the heat which the 7m's intake manifold absorbs. This lend me to do some searching about phenolic gasket spacers. I found this: http://tech.mirage-performance.com/teflon-insulating-gasket.html

and info on great results posted here:
http://www.autospeed.com/cms/A_0401/article.html

does anybody have any experience making such gaskets? I intend on asking my materials professor about a recommended material tomorrow but thought some input from others would help as well.

 

[Tire Shredder]

I just had a conversation with my professor, who teaches "structures and properties of materials" about my gasket project. It seems we have settled on teflon. It's got a few great properties:

1) non porous, won't leak air through it's self
2) high specific heat capacity, as good as air and even better than porcelean!
3) easy to cut/shape
4) ability to withstand heat is far better than what is needed...about 500F
5) relatively inexpensive.

I'll be ordering some soon.

 

[supraguy@aol]

Let us know how it goes- I have a phenolic intake gasket, but it's only like 1.5mm thick. Dunno if it'll do much when I install it.

 

[Poodles]

they make them for our cars, but that of course takes the fun out of it...

ceramic coating the intake would help as well, same with the ports, ect...

 

[Tire Shredder]

I got some work done that I am somewhat proud of so I thought I would share. although it's not terribly exciting, I thought some pictures were in order. I've been working away with the little spare time I have and just finished up the upper intake manifold today. before I started work I attempted to clean it but to no avail...it was impossible to get a toothbrush in there. I took it to the machine shop to have them "clean it" they ended up hot tanking, bead blasting and chasing the threads. Cost way more than I expected but it is perfectly clean now...probably money well spent in the end. Made it super easy to work with.

This pic shows how bad the casting is on the #2 runner, it's not round at all. I've started work on the #6 at this point.

The Y-pipe openings. Done.

This illustrates the nice finish I was able to get on #1 and #2

#5 and #6 finished with 120 grit aswell, looking nice.

I can't explain why this looks so messed up, but it maches the gasket and the runner properly I hope it doesn't creat a differential in air flow...

The whole thing done

runners bolted to the upper section

it took a lot of time to get to this point, but here you can see just how well I matched the gaskets. this is the runner bolted to the upper...you can't tell there's a seam at all! all ports look like this.

 

[Tire Shredder]

update yaay! I made some great progress on the head lately, here's a couple finished intake ports!

short side radius is cleaned up, valve guides are countered and I have a better "ramp" up to the valve guide. I narrowed the port dividers and rounded them. I was worried about knife-edging them too much and not being able to get a good radius but I am very happy with the results. I removed the machined step around the valve seat aswell, then polished it all too a pretty damn shiny finish! . I did some more reading and talked to my thermo prof....everything points to a smooth surface. Any turbulence that would help aid in atomization with a rough surface would be helpful mainly in carburated cars, but fuel injectors do a great job of atomizing and ours spray right ontop of the valves...so polished it is.

I have yet to polish the combustion chamber itself.

here's some pics!

i'm very happy with the results, all of them look the same now. not too shabby for a first timer and a street car! i'm getting more excited and more obsessed the more I work on it! the pictures really don't do it justice, it's very shiny and smooth! when I am done and finished, I'll get some better ones.

as always, comments are welcome

 

[BlackMKIII]

Good luck! Hope you get a "freak-of-nature" out of this!