High rpm components, let's cover everything.

[s turbo 87]

Okay, I'm going to be building and upgrading my cylinder head over the next few months and I've got some questions regarding what to use. I realize that a lot of this information has been covered, but I get such generalized search results when I try to dig through everything on the forum. I figured my questions and the knowledgeable responses from other members would benefit many people with similar high rpm goals as mine.

First of all, I intend on using a large frame turbo (70+mm) and so it would be nice to be able to spin my 7m a little higher than the factory 6750rpms. I'm not concerned about the engine management aspect of it at this point, but more about what mechanical parts would best suit my build. (or any other higher rpm, big power builds)

1.) I would like to rev to at least 7500 and maybe 8000 if thats not too out of the question (input would be nice on this). I understand that the BBC comp cams inner valve springs are a good upgrade over our stock springs if you are staying within or near the stock rev limit. I'm just wondering what other springs people have successfully used for higher rpm applications (dual valve springs as opposed to single, I'm assuming). I'm sure I can't go wrong with all of the cylinder head components that Ferrea offers, but what are other good alternatives that you've had experience with?

2.) I have also read on here before about using 2JZ valves as an upgrade, but I searched and couldn't find the information I had read on them before. I believe they are oversized, but by how much? I believe I remember reading that they are slightly longer and would need to be cut by a machine shop to fit properly? Also, if using 2j valves is an effective and cheaper alternative to buying aftermarket valves, then I must also ask if 1jz and 2jz valves are interchangeable because I was offered a set of 1j valves from a local guy.

3.) Another question I have is regarding camshafts. I had intended on using BC cams, but I've been hearing so many mixed reviews on them, some say they are great and others say not to waste my money..what do I really need to know about them? Also, I believe upgrading to 264/264 cams still doesnt make it an interference motor, but since I plan on revving higher with a larger turbo, would I benefit that much by going with 272/272's? Would there be a noticeable difference and approx what would it be? ( i know thats a fairly general question, but a hypothetical answer will do). I have also considered regrinds, I've been asking around to find a local shop that can do this and I believe I have a few options, but does anyone have a specific place that they can vouch for that does a good job of this that won't break the bank?

4.) I also know that if you have higher rpms in mind, the stock pistons and rods may also a restriction. I have eagle rods and probe forged pistons, will these be good for my high rpm goal? What other provisions should be made to the block to withstand an extra 1000 or so rpms? I know to upgrade the oiling system by shimming the pump and using an AN line/fittings in place of the factory hardpipe. I have a crank scraper that I intend on using as well. I have seen someone on here modify the stock oil pan to hold more oil, if someone knows who did that or could link me to that thread I would appreciate it. Talking to other more experienced engine builders (of domestic V8s) I have heard a lot about using a main cap girdle. Nobody that I know of produces these for a 7M but I believe if its worth it, I could custom make my own or have one made. Just picturing my block in my head right now though, it doesn't seem like there would be much room for one, input?

5.) At the power levels that I am trying to achieve and the extra rpm, I also think it would be a good idea to upgrade the stock crank pulley. The only solid and good upgrade to this that I have seen so far is from ATI, are there others? It is a good idea to upgrade the crank pulley right? I do know to stay away from undamped pulleys.

6.) Are upgraded cam gears a must for my intentions or would it be an added benefit to provide more room for adjustment (or error).

I'm sure I'm forgetting some things here, but what other mechanical aspects of the 7M need to be touched on to safely rev higher? There's a lot of information scattered around, but let's try to get everything into one thread possibly. If this thread already exists, I'm sorry, and please provide a link with all of the information I am seeking.

 

[Ma70.Ent]

For the modified oil pan, I think you were talking about 927mgtepat, in this thread:

http://www.supramania.com/forums/showthread.php?t=66487

 

[IJ.]

Biggest issue I had getting the motor to stay together above 8000 for sustained periods was Valve springs.

 

[Zumtizzle]

With Cams, You should dial them in and use adjustable gears, i like fidanza gears. But if you can get a hold of old school hks/jun gears that would be ideal.

 

[92nsx]

Keep a eye on ebay. I bought my AEM cam gears there for $90 shipped for both of them, brand new from AEM. AEM sells old stock items on ebay to get rid of them. I found them a couple months ago for $45 shipped each. Ya there red (witch i do not like) but the price was right AEM's name on bay is aem_dc

 

[gofastgeorge]

If you want the full story on the 7M oil pan extenders,
go back to this thread:
http://www.supramania.com/forums/showthread.php?t=31378

This is where they first showed up.
They are less than $20 each from Speedway motors.
www.speedwaymotors.com

If you dig through that thread, the actual part number is listed.
It used to be stickied, but was dropped for some unknow reason.

You can also get some ideas from this Sport Compact Car reader's rides post.

http://rides.sportcompactcarweb.com/ride/1007534/texas-cressida/1989/toyota/cressida/index.html

He uses TODA inner shim buckets, and turns his 7M to 8500 rpm.

 

[92nsx]

^^^^ Part # for Oil Pan Bulge Add-On is 91015119. I wish i would have read about those about 2 months ago :cry: I would have welded them in to my pan no prob, but now since the engine is back form the shop and in the supra its kind of too late. :3d_frown: DAM IT!

Also pick up part # 91011522 witch is Fuel Pump Block Off Plate, B/B Chevy, Chrome Finned Aluminum, it is used to get rid of out "J" pipe on our fuel system. Here is the best part only $6, and its go fast chrome!!!!!, thats way cheaper then even ebay.

Also order 2 sets of Comp Cams valve springs # 975-12 SPI has them for someting like $65 witch is $10 cheaper then you will find anywhere.

Also look up member suprarich form SIP Racing http://www.sipracingmailorder.com/servlet/StoreFront
He hooked me up with all my internals, cams, valves, everything I spent something like $2000 with him over this past winter months. He has the BEST prices around and I searched around. If you order anything form him let him know 92nsx gave you his name.

 

[Doward]

Lighten the rotating assembly.

Lighten the valvetrain assembly.

Springs of sufficient strength.

Cams of sufficient flow capability.

Exhaust/Intake of sufficient flow capability.

 

[Adjuster]

I'm going to play devils advocate here for just a second.

1)With "stock" gearing, the 88T 5 speed tops out at over 170mph.. Do you need, or want to go faster than that? (Higher engine RPM will allow it, but a gear change would be less money...)


2) Do you want more power?

You can get it by spinning the motor faster, and pumping more air to burn fuel with, or you can just pack more air into the motor... (IE: Turbocharge it...)

It is a proven deal to get the 7M pretty much reliable if you keep the stock RPM limits, and concentrate on the important stuff.
1)Tight tolerences on your bearings, oil pump and head gasket surfaces.
2) High quality forged pistons.
3) ARP rod bolts, or upgraded forged rods from Pauter, Crower etc.
4) Oil system mods. (Search it.)
5) Larger valves, and Comp Cams springs. Everything else stock works fine.
6) Your choice of T4 based turbo. Do you want low/mid power, or top end howl? Choose your turbo accordingly.
7) Fuel. Your going to need lots of it, so either dual pumps, or a single large pump. Big injectors are a must if you want serious power.. 680cc or larger IMNSHO... (I have 780s now..)
8) Piggyback like the Maft Pro, or stand alone ECU, but the stock TCCS is not going to handle your massive power needs without some help and trickery..

I read back through your questions, and really think if your coming from a CT26 and less than 400 at the wheels, that you will be very happy with a T70 based build, that still turns stock RPM limits, but has say 600hp potential...

More than that is really mostly tire smoke..

 

[s turbo 87]

Thanks for the responses.

Whats the deal with fitting 2J valves in the 7M head? And are 1jz valves interchangeable with the 2jz ones?

 

[JimR]

While not a "component" in the physical sense, a complete balancing job of the entire rotating assembly is a must for higher rpm's.

 

[Adjuster]

JZ valves in the 7M head are only a theory as far as I know. (And I know a few of us have at various times, kicked around the idea..)

Here is the poop.

The valves are 1.5mm larger stock than the 7M valves. (From what I remember...)
The valve stems are the same size diameter, but they are longer by about .5mm. (Also from the top of my head, I did not memorize the numbers...)

The 7M valve seats can be cut so 1mm oversize valves work fine. I know this because I have 1mm OS stainless valves on the stroker motor head.

There is not much material left of the seats however with them cut for just 1mm, so I'm not sure you could go the other .5 or not. (Most likely could... but again, I don't know of anyone that has...)

So, if you had to remove the seats, and replace them all, it would not be very cost effective....

On the valve stem side the thought was to have the cams cut with a new base circle, to take advantage of the .5mm longer stem, and get more lift for "free" from your stock cams... No welding needed, but it's most likely they would need to be hardened after the machine work, or they might not hold up well to extended use.

Pretty much any machine shop can stay with the stock length however, just grind down the stems, no big deal. (They are not under any rotating force, the shims and buckets/lifters take the sliding/rotating force from the cams is absorbed there for the most part.) Now, I've seen valves/lifters setup so they rotate the valves all the time, and the 7M head might just do that.. the lifters do spin freely in the buckets, but I don't know for sure if the buckets turn much, if at all under the pressure, and if they in turn, rotate the valves much, if at all either...

In theory, it keeps your valves sealed up better over time to have them rotate slightly from what I've learned throughout the years... Urban myth anyone?

So, JZ valves in theory should fit, but again, it is not something that anyone I know of, has done actually. (There was a NA 7M being built for awhile where they were going to do this, but I do not know if they did or not.) He was trying for a 300hp 7MGE, so it had a few tricks, and then some.

To summ this up.

1) The available 1mm OS stainless valves are the best deal.
2) You can use stock seats with them.
3) You can use the Comp Cams BBC valve springs for a simple, and cost effective upgrade to stock ones.
4) Port work around the sharp edges, and angles will pay off most.. Leave the intake side alone for the most part, and open up the exhaust side only slightly.. Leave some, about 1mm of "lip" where the port meets the gasket.. this induces tumble to the flow, and helps with low end tourqe, especially on the stock log type manifold...

I cut my valve guide posts out on the exhaust side, there is just a smooth round runner with the valve stem poking out, and on the intake side, the guide is ported into a "wing" shape to smooth air flow in...

Seems to have worked...

 

[s turbo 87]

Yeah I talked with my machine shop about the JZ valves and I think we have ruled them out.

The guy doing my port work seems to know what he's doing. I don't know that he has ever ported a 7M head or not, but he has ported everything from a sbc head to a cummins 24v head, to tractor pulling heads, to lawn mowers, hondas, etc. He was going into fluid dynamics and whatnot when we were talking about it.

What do you mean by a "wing" shape on the intake guides? Like an airfoil? Why not cut them like the exhaust? Does that relate back to the inducing tumble to the flow principle?

 

[Ma70.Ent]

So, JZ valves in theory should fit, but again, it is not something that anyone I know of, has done actually. (There was a NA 7M being built for awhile where they were going to do this, but I do not know if they did or not.) He was trying for a 300hp 7MGE, so it had a few tricks, and then some.

Defiant7M (the one you are probably talking about) is using 2JZ Valves I think.

 

[IJ.]

7M guides are quite short anyway I wouldn't cut them at all just blend them.

 

[bfr1992t]

1.5mm over valves here, 7 yrs ago now. Work just fine.

 

[Adjuster]

bfr1992t, did you have to replace the valve seats? Or have you ported them out for more flow, or just cut the valve angles, and left it at that? (Most of the valve cutters/grinders I've seen, leave sharp edges, or don't cut the ID of the valve seat at all. (They only grind the angles.. not open up the ID of the valve seat.)

IJ, I was trying to get the most flow possible out of the exhaust side, and as you noted, there is not all that much valve guide ramp/bump in there anyway, so I just removed it completely on the exhaust side.. I figure the exhaust flow is pretty turbulent anyway too..

On the intake, I just turned the guides into airfoils around the stems. (Cut most of the metal away on the sides, and then rounded the intake manifold side, and tapered the intake valve side, like an airplane wing if you will...

One last question.. Using the 1JZ valves, did you have your cams re-ground, or did they just shorten the valve stems to work with your stock cams?

 

[IJ.]

Greg: My view on this is the longer guide helps more with guide and stem longevity than flow so I leave em long
(I usually have a reason for everything I do)

 

[suprarich]

The oil pump drive shaft should be hardened for rpms above 8k. Mibrum used to break them spinning 9k rpm, before switching to a custom made billet shaft. Of course he then switched to dry sump. Also don't forget a bigger damper from stock.

 

[Adjuster]

The oil pump drive shaft is about the only thing I'm worried about on my build. (Other than the piston slap issues.. and the fact that I'm still futzing around with my car in the garage.. )

I agree, for long term reliability, the longer valve stems would be a better deal.

After I cut mine down, I almost replaced them on the exhaust side with the new ones I had laying around. (They came with the valves.) But in the end, decided to go for it, and run them removed completely from the runner.

Funny thing is, they have been fine for the past few years.. (My car has been sitting around for that time.. ) And I went out today, looked at the dusty Supra, and decided it was much too nice a day to work on the car.. Jumped on the FZ1, and broke some laws.. )

Problem is, in the past 18 weeks now, I've been home only on weekends.. and the one week that I did not work, I left town midweek for "vacation" with my wife and kids.. I really need to spend more time at home one of these days.