Composite hg... Hp/boost limits

[Zrain25]

I know most people run mhg and arp studs. I'm gunna be running arp studs and rod bolts with new bearings when I do the engine over.

My current mods are

Fmic
3 in exhaust
Intake
Gauges
And a downpipe coming in soon

Future mods are

550/Lexus
Walboro pump
Fpr
And a 57 trim

My question is will a composite hg handle those mods with arp studs. I eventually want to get to 400hp tops I'm not going over that. The car will be used as a weekend car. No drag way or tracks

 

[emericaskater285]

It should be alright. If you are going to be pulling the engine to do the rod studs, you might as well have your head and block decked, and run a MHG instead tho. That way you have a little more insurance. I am regretting I did not do a MHG while I had my engine apart, because now I want to push 500+ on the stock block. I feel the head gasket will be holding me back.

 

[super51fan]

If you are going to go for more power from your engine, Why would you go through all the work of doing a head gasket replacement and not use a steel headgasket. You would be better off using stock headbolts and steel headgasket than using OEM style gasket and arp bolts or studs. Just my two cents.

 

[Zrain25]

I was just wondering what my options are I know 2 other supra running 15 psi on composite hg with arps for over 2 years I was just wondering what your opinions are on composite hg with arps

 

[emericaskater285]

I was just wondering what my options are I know 2 other supra running 15 psi on composite hg with arps for over 2 years I was just wondering what your opinions are on composite hg with arps

I have been running on 16+ for over a year, beating on my car constantly, and haven't had any problems. Do I recommend it? No. Can it be done? Yes.

I am going to be building a block on the side, that way if she pops, Ill have one ready to go. This spring, I am planning on setting the record for the highest horse 7m with a composite HG. Not sure what the current record is, but I plan on breaking it. (If anyone has the record for the highest horse composite HG 7m let me know, I have been looking around, but cant find anything.)

 

[Zrain25]

Ya I'm not looking to go over 15 psi but if the engine is out of the car I might to mhg or composite. Idk yet but knowing ur running 16 psi on a composite is not a bad thing

 

[Zrain25]

Ohh and the highest hp I read was 505 with a composite hg...

 

[emericaskater285]

Ohh and the highest hp I read was 505 with a composite hg...

Thanks, I actually found a guy on SF named X-man ran 510 on toyota HG.

Anyways, I would actually recommend you do a metal head gasket. I was in your situation 2 years ago. My HG went out, and I didn't want to pull my engine and deck the block. So I went with a composite HG. Well, now I am totally regretting that decision, as I want to push the limits of this engine, but the HG is really holding me back. My original goals were 350 hp on a 57 trim, 550cc's and Lex AFM. Well, now my goals are going to be almost double that come this fall, or next spring.

Again, you may be different, but when the modding bug bites, it bites hard!

 

[Zrain25]

I now about the mod bug. Happen with my 7.3 diesel. And if u think supra parts are expensive.... Diesel is in a whole different league I can rebuild my supra with good parts for less then a set of injectors for my truck.., never mind the 140.00 oil changes lol

 

[Zrain25]

Rebuild the supra motor I meant

 

[xnuclear23]

You definitely can make decent power on a composite head gasket as long as the rest of the engine is in good/decent condition, but it would just be best to go mhg. When I first got my supra and it blew the hg, I went ahead and just did a composite headgasket instead of doing a mhg and now I'm at the point where I need a mhg on my car. I would suggest to just go ahead and do the mhg from the beginning so that you never have to back track and redo what has already been done, also since you are planning to run more than 12lbs of boost i would just say go ahead and get the mhg done. It will save your ass in the end; lowering the chances of a bhg and allowing you to achieve whatever power goals you set/change your mind to...

 

[Zrain25]

Ya I might just go for a mhg I'm gunna start buying parts for the rebuild soon. Start with the little stuff like the studs and rob bolts, engine gasket set, I can't wait to tear this beast out of my car

 

[suprarx7nut]

This is an easy question. If you can pull the engine and have it machined then go MHG hands down.

If pulling it and having it machined isn't in your plan, then you're going with a composite.

Stock hg on a 7m can handle more than many seem to believe.

Sent from my Galaxy Nexus using Tapatalk 2

 

[Zrain25]

Well I just took my valve covers off and I got arp head bolts so the guy seemed like he knew a little about the 7m. I might just be skipping on the engine rebuild because it running perfect and now that I found the arps I'm happy with it

 

[xnuclear23]

Just run it how it is if there's nothing wrong with it now and the day the hg blows or you want to perform some upgrades/rebuild then at the point take the engine out and slap a mhg on..

 

[SupraMedical68]

Just run it how it is if there's nothing wrong with it now and the day the hg blows or you want to perform some upgrades/rebuild then at the point take the engine out and slap a mhg on..

This + 1

Btw, wasn't Devin running high boost with a 57trim CT on a stock composite head gasket with ARPs for awhile?

 

[Nougie]

I have been running on 16+ for over a year, beating on my car constantly, and haven't had any problems. Do I recommend it? No. Can it be done? Yes.

I am going to be building a block on the side, that way if she pops, Ill have one ready to go. This spring, I am planning on setting the record for the highest horse 7m with a composite HG. Not sure what the current record is, but I plan on breaking it. (If anyone has the record for the highest horse composite HG 7m let me know, I have been looking around, but cant find anything.)

232bhp....Get it? lol jk tho. Im sure a composite can hold up to about ~300-380hp good enough but as they said, if youre gunna pull the motor, u might as well just go MHG for cheap insurance and peace of mind

 

[Zrain25]

I'm not pulling the motor anymore. I'm Just gonna put a 57 trim and 550s/Lexus. And the other supporting mods most are already done still need fuel pump, exhaust elbow, wideband, and fpr

 

[Nick M]

Most people here look at it from the wrong angle. When the engine gives due to pushing it too hard or down right negligence in the tune, what do you want to shoot out of the block? A composite headgasket, or a connecting rod.

 

[Dan_Gyoba]

The limit is all in the tune.

Reg Reimer's '82 Supra was running a stock gasket, and stock bolts torqued to 72 ft lbs, and putting down more than 400 at one point in time, though the log entry at http://suprasonic.org/gtestory/ lists 339 RWHP and 398 ft-lbs torque at 14.5 psia. I know from talking to him he was later running 18 lbs regularly, and up to 21 psi at the track occasionally with a lot more HKS goodies, and the techtom ROM boards replacing the stock ECU, but still on the stock gasket and bolts.

Other people have blown stuff apart without getting to the 300WHP mark.