Toyota HG design and power capability?

[SupraTurbo1989]

Lapping is a finishing process used AFTER the block/head is machined NOT as an alternative...

By hearing that, I assume you are insinuating that I basically NEED to get my block decked at a machine shop if I am going to run a MLS head gasket. Darn! Well taking that into account, do you think I would be OK running a new Toyota HG and ARP's if I were to push mid 400's with probably something along the lines of a VPC/AFC?


Any help would be greatly appreciated!!!!

 

[IJ.]

As I posted earlier the Composite will be fine at those power levels as long as you keep it out of detonation, 1 rattle will end in a bad day..

I tend to tune safe so wouldn't have any concerns I also maintain my cars well so that removes another possibilty of rattle from a dirty fuel filter or a bad pump.

 

[SupraTurbo1989]

As I posted earlier the Composite will be fine at those power levels as long as you keep it out of detonation, 1 rattle will end in a bad day..

I tend to tune safe so wouldn't have any concerns I also maintain my cars well so that removes another possibilty of rattle from a dirty fuel filter or a bad pump.

Gotcha. Any recommendations on how to keep it out of detonation? Like I said earlier, the car will most likely be running on a VPC/AFC combo for awhile. What's your thoughts on the VPC/AFC?

 

[BlackDevilSupra]

^^^^
Short of going full standalone EMS, I would suggest water / meth injection..
Just have to realize that the 7M's ecu is 1980's computing technology, and it just can't do much with the limited memory and processing speed required for engine performance beyond stock HP. Hence why it's so important to truly consider standalone EMS. No standalone, then substitute the benefits of water/meth injection to inhibit detonation.

 

[Steve_N]

What's your thoughts on the VPC/AFC?

They work well together. My son runs that set up in his SC300 However I run the Maft
-Pro in my A70 & like it much more.

When I rebuilt my 7m yrs ago (04) I got a Toyota rebuild kit. I used every gasket & seal in the kit but I tossed the Toyota HG & used Felpro HG & ARPs. At the time there was lots of scuttlebutt that the Felpro was superior to the stock HG as composites go.

 

[SupraTurbo1989]

When I rebuilt my 7m yrs ago (04) I got a Toyota rebuild kit. I used every gasket & seal in the kit but I tossed the Toyota HG & used Felpro HG & ARPs. At the time there was lots of scuttlebutt that the Felpro was superior to the stock HG as composites go.

Is that still the case? I was under the impression that the best composite HG is an OEM Toyota.

 

[benchwarmer]

No idea which is better but I've been using Fel-Pro for years in almost a dozen cars and I haven't had one fail on me yet. They get a bad rap sometimes in the import community but I've never had a problem with one.

 

[suprarich]

Well I would do that, the only thing I am concerned about is getting the block surface smooth enough to seal properly with a MLS head gasket. Although I heard the Cometic brand is a tad more forgiving when it comes to surface preparation, I am still weary if I can get the block smooth enough with it still in the car.


On the other hand, I have heard that I could buy a lapping block and lap the block myself with it still in the car, but after hours of searching, I have yet to find where I could purchase/rent on of these so-called "lapping blocks".

Cometic being more forgiving to prep work is an internet rumor at best. It is simply not true. Cometic WANTS to see a ra of 50, hks WANTS to see a ra of 35. This in no way means that cometic is more forgiving. It simply means that hks WANTS you to use a higher finish level than cometic WANTS you too. No test have ever been done to find the threshold of failure due to RA levels on either gasket. In fact, if you compare a hks gasket side by side with the cometic, the coating on the hks is much thicker.

 

[CyFi6]

Sounds like the bottom line is budget, and if you cant pay then you shouldnt play! Go with a stock head gasket and dont aim for high horsepower numbers. Once you can afford it, go with the whole nine including forged pistons etc with a MHG. No sense in trying to make lots of power with a half assed motor. I know this is used a lot, but it is usually true. Cheap, fast, reliable...choose two...

 

[SupraTurbo1989]

So has anyone else had good luck with a Toyota composite HG lately? I still have yet to put my motor back together, but will likely do it soon and am still unsure on what head gasket to use. I know DSM guys have had good luck with composite head gaskets but I understand that isn't a fair comparison since it's a totally different platform. Obviously I will be using ARP studs and my head is decked. I just don't know if I should run the risk of using a MLS gasket and it not sealing, or using a composite and it would fail due to cylinder pressure. I would like to make at least 500whp on E85 with a good tune.


Jeff

 

[suprarx7nut]

I'm a huge fan of composites, but 500 HP is pushing it. I'm sure it *could * be fine but your tune will need to be great and safe.

Sent from my Galaxy Nexus using Tapatalk 2

 

[Nick M]

Hmm, I swear I heard that Toyota changed the head gasket design for the 7M a number of times since it was released.

For the record, people saying it doesn't make it so. Toyota changed all of their composite headgaskets, recalls or not. Recall because one had a real problem. The old 3.0 V6 that was in the early 90's 4Runner, the 3V series.

It kills me that I see all the local 2J's making 800+hp on un-opened motors.

They don't last very long. Going back in time, Mark Tozer ran about 900rwhp on a stock shortblock. It lasted 31,000 miles, according to him. It depends on how you look at it as to whether or not that is good.

 

[SupraTurbo1989]

I'm a huge fan of composites, but 500 HP is pushing it. I'm sure it *could * be fine but your tune will need to be great and safe.

Sent from my Galaxy Nexus using Tapatalk 2

Well I'm thinking that with the use of E85, I'll be able to greatly reduce the risk of detonation which would likely increase the chance of survival at higher power levels.

I feel it can be done, I just want some confirmation and assurance from you guys.

 

[Zrain25]

I'm Gunna be running 550s/Lexus and 57 trim with a safc neao on composite hg/arps should be a little under 400 whp

When it blow I'm rebuilding and going mhg

 

[Dan_Gyoba]

When it blow I'm rebuilding and going mhg

:nono: I can't understand this attitude. I'd personally rather hold off on power until I have something that can take it. It's much easier/cheaper to rebuild an engine that hasn't overheated and warped stuff, possibly spun a bearing, gummed up the oil system and had bad things happen to it.

I'll upgrade things as I go, sure, but I never plan on things failing. (Plan FOR things failing is different.)

 

[Zrain25]

Cuz my car already has arp head studs it can easily handle 350whp the engine rums mints. That's why I'm adding stuff to it. If I wasn't confident the engine could handle it I wouldn't do it

 

[SC61 MK3]

Toyota oem gasket with arp studs will handle 400whp all day with a SAFE TUNE. I know because I've been running the same setup for a few years now with no problems and its my daily driver. MHG no doubt is better but only if you can resurface both the head and block for it or it will fail eventually no matter what.

 

[Poodles]

The issue with the "when it blows I'll rebuild" mentality is that if it blows, it's going to overheat and anneal the head. Good heads are getting rare and expensive, so it's dumb to cut corners in the first place...

 

[Zrain25]

^^^ that is true but I doubt it will blow from 5 months of use I'm ripping the engine out in the winter. And I don't beat on my car I know the engine is still 25 yrs old so I try not to beat on it.

Plus if I blows I will go 2j and then join the group of people who shit on 7ms ... Kidding

 

[SupraTurbo1989]

I wish X-man could chime in as I'm curious as to how this stock head gasket 7M is holding up. 500whp, pretty impressive.


http://www.youtube.com/watch?v=j_8CIbmKGJY&feature=share&list=FLevcknwk0UH82bhUFvKKo4A