franco101 Posted May 16, 2011 Report Share Posted May 16, 2011 What is max boost that is being run safely by members. Please include what turbo and if your tbi or mpi and if you know what head gasket you have and if block has been oringed . I have a 18g 06 with mpi on an ajusa running 18psi. But I think I hurt gasket when I was tbi running 22psi. Now if i run anything over 15psi, coolant comes out of overflow. Am going to pull head soon to investigate. Franco Link to comment Share on other sites More sharing options...
BOHO Posted May 16, 2011 Report Share Posted May 16, 2011 What kind of map sensor is on the SDS? Link to comment Share on other sites More sharing options...
dmyers151 Posted May 16, 2011 Report Share Posted May 16, 2011 Technology, Phinko & Charles Gardner are all running o-ring blocks up around 30psi IIRC. 4cylfury just posted about pushing 30psi without o-rings. 4cylfury Link to comment Share on other sites More sharing options...
Shelby Posted May 16, 2011 Report Share Posted May 16, 2011 just because some one else does some thing does not mean you can , besides you already have a blow head gasket Link to comment Share on other sites More sharing options...
OPTIMUSPRIME Posted May 16, 2011 Report Share Posted May 16, 2011 I personally think 14 psi is good but if you are still running the OEM manifold you are asking for trouble since the exhaust gases dont exit fast enough through that straw hole from the OEM manifold. If they dont.....well.....you know what happends. Remember the TB is a little larger than the hole from the exhaust and now you have a MPI with bigger TB... What does that means? PRESSURE!That just my reasoning Link to comment Share on other sites More sharing options...
BOHO Posted May 16, 2011 Report Share Posted May 16, 2011 He is MPI... Link to comment Share on other sites More sharing options...
Shelby Posted May 16, 2011 Report Share Posted May 16, 2011 He is MPI... makes no diff,, if he is still on oem head bolts Link to comment Share on other sites More sharing options...
S.M.B Posted May 17, 2011 Report Share Posted May 17, 2011 stud it, copper head gasket and boost the crap out of it lolhttp://www.scegaskets.com/Pro-Copper-Head-Gasket-p6598397-1-2.html (head gasket) Link to comment Share on other sites More sharing options...
franco101 Posted May 17, 2011 Author Report Share Posted May 17, 2011 Ok this wasn't supposed to be about if I have a blown head gasket or not. By the way if I run stock boost then no coolant problem. Also I test pressured coolant system cold and it holds 17lbs for half hr... I have arp studs too. Like the idea of copper gasket, that's what three different guys at the track said to use. Back on topic. I just wanted to know what's the max safe boost that guys are running. I am loving my 300rwhp at 18 psi. but want to know how much higher I can go. Just because someone is running 30 or more psi doesn't mean I am going to try it. And I don't think anyone ever ran high hp without running high boost, but i could be wrong. Franco Link to comment Share on other sites More sharing options...
Ironside Posted May 17, 2011 Report Share Posted May 17, 2011 Jk Oh you said boosthttp://www.starquestclub.com/forum/public/style_emoticons/default/unsure.gif Link to comment Share on other sites More sharing options...
chiplee Posted May 17, 2011 Report Share Posted May 17, 2011 (edited) Watch out. Last time I had a "boost pressurizing the cooling system" problem that only happened above stock boost, it was a cracked block. Edited May 17, 2011 by chiplee Link to comment Share on other sites More sharing options...
Caliber308 Posted May 17, 2011 Report Share Posted May 17, 2011 What is max boost that is being run safely by members. Please include what turbo and if your tbi or mpi and if you know what head gasket you have and if block has been oringed . I have a 18g 06 with mpi on an ajusa running 18psi. But I think I hurt gasket when I was tbi running 22psi. Now if i run anything over 15psi, coolant comes out of overflow. Am going to pull head soon to investigate. Franco 18G: 16 to 25 psi efficiency range. So....I'd say 20 psi would be a safe bet.Larger Injectors or MPI required for boost over 15 psi. Bill Link to comment Share on other sites More sharing options...
Technology Posted May 17, 2011 Report Share Posted May 17, 2011 Over 9000. 1 Link to comment Share on other sites More sharing options...
Funky Phil Posted May 17, 2011 Report Share Posted May 17, 2011 Daily, I run 20psi on 93oct with a much larger turbo than yours. And it's still on the stock exhaust manifold. Without ignition control I'd stay right where you are. If you wanted to go up somemore keep an eye on you spark plugs and maybe retard your dist a degree or 2. Tech and 4cylfury run cornoil so that allows for higher boost. Are you still running the stock knock system? Link to comment Share on other sites More sharing options...
Funky Phil Posted May 17, 2011 Report Share Posted May 17, 2011 I've also run up to 28psi on a 67mm turbine without orings. Just arp's and an ajusa Link to comment Share on other sites More sharing options...
Technology Posted May 17, 2011 Report Share Posted May 17, 2011 A really smooth block surface (good machining) allows higher boost without o-rings too. Link to comment Share on other sites More sharing options...
Indiana Posted May 17, 2011 Report Share Posted May 17, 2011 What you may have is a leaky intake manifold-to-head flange gasket. Either the front or rear coolant passage. A gasket that is compromised at higher boost can let it enter the cooling system and its usually the rear slot and someone didn't put a film on each surface before they put the gasket on or they put on too much. The intake manfold does warp. The OEM intake gasket is thin paper but I've seen some layered ones with a tin web in the middle and those suck the big one. Coolant enters the layers and the gasket will fail just keep that type for a carbureted engine. The popular one is the thick Felpro which can help you seal up a warped intake but they used to also include the thin one in the set. Check the nuts on the intake and see if any are loose. Get a mirror and look under the intake and look under where the slot is towards the rear of the head and see if there's a clean spot where coolant has been seeping out. Link to comment Share on other sites More sharing options...
chiplee Posted May 17, 2011 Report Share Posted May 17, 2011 What you may have is a leaky intake manifold-to-head flange gasket. Either the front or rear coolant passage. A gasket that is compromised at higher boost can let it enter the cooling system and its usually the rear slot and someone didn't put a film on each surface before they put the gasket on or they put on too much. The intake manfold does warp. The OEM intake gasket is thin paper but I've seen some layered ones with a tin web in the middle and those suck the big one. Coolant enters the layers and the gasket will fail just keep that type for a carbureted engine. The popular one is the thick Felpro which can help you seal up a warped intake but they used to also include the thin one in the set. Check the nuts on the intake and see if any are loose. Get a mirror and look under the intake and look under where the slot is towards the rear of the head and see if there's a clean spot where coolant has been seeping out. Interesting. I almost always agree with everything you say Indiana, but this time I think there is about zero chance that this could be his problem. Link to comment Share on other sites More sharing options...
The Rabbit1 Posted May 17, 2011 Report Share Posted May 17, 2011 Interesting. I almost always agree with everything you say Indiana, but this time I think there is about zero chance that this could be his problem.if it holds at stock boost but not higher, with having arp studs, it is possible. Or his block isn't flat, I would think he would've fried a head gasket if he lifted it a few times myself. Link to comment Share on other sites More sharing options...
Tim_C. Posted May 17, 2011 Report Share Posted May 17, 2011 And I don't think anyone ever ran high hp without running high boost, but i could be wrong. Team Mitsu ran over 600HP naturally aspirated on a 2.6L.I have seen boost leak through the intake gasket from a runner to the coolant passage and pressurize the coolant system, but it did also leak under the manifold too. Link to comment Share on other sites More sharing options...
Shelby Posted May 17, 2011 Report Share Posted May 17, 2011 op said > I have a 18g 06 with mpi on an ajusa running 18psi. But I think I hurt gasket when I was tbi running 22psi. Now if i run anything over 15psi, coolant comes out of overflow. Am going to pull head soon to investigate........................................................................................................................................................................................................................... it may be too late BUT DO NOT PUT head just yet with a dead cold engine ,remove all spark plugs ,, over fill the rad till the level is above the sealing ring for the cap, now make sure the batt is full charge'd ,do a comp test useing a remote starter swt,,( so you can watch the rad inlet) when doing comp test do an extend'd crank all the time watchingthe colant level, not the comp gauge numbers , if any cyl shows movement of the coolant , take note of the number of the cyl,,next remove the valve cover and loosen the rocker arm assy,, this time do a leak down test with 120 lbs compress'd air pressure , do each cyl and pay special attention to the one that you had movement in earlier ,,, if none of the cyls show any collant movement the head gasket is fine if you do not want to bother with looseing the rocker arm assy,, do this rotate the engine to #1 tdc fireing ,, place the trans in 5th gear and lock the parking brake , do the lead down test,, next move on to #3 tdc , same thing in 5 th gear loc the car with parking brake ,,do each cyl this way ,, in order 1-3-4-2 easy way to find the odd cyls tdc is while the #1 mark is at tdc, make another mark on the crank pully at dead bottom that you can see ,doing this alows you to start with #1 tdc, rotate the crank 1/2 turn use your new mark for #3, rotate the crank 1/2 turn back to oem tdc,for cyl 4, rotate 1/2 turn to your new mark for cyl #2 , engine rotate'd 2 full turns, done do not forget to place trans in 5th gear and loc parking brake for each cyl test'd ,,to test inj houseing base gasket install rad cap and loosen or remove the egr valve now leak test any cyl if the base gasket is leaking coolant will drain out of the egr passage you can also test the valves for proper seating at same time any excessive air leaking heard from intake or exh indicates leaking valves,, from crank case indicates broken piston rings ,,noise from crankcase means one cyl much diff from the others if you take a little time and do this you can pin point the exact cyl with a problem or the lack of any problems , eather way it's a win win Link to comment Share on other sites More sharing options...
Indiana Posted May 17, 2011 Report Share Posted May 17, 2011 (edited) It doesn't have to pressurize the cooling system all it has to do it blow it out a crack and just a thin area around that rear port on the head flange. If it wasn't sealed well in the beginning it might take some time but it will leak and it will leak out the bottom not the top. The top has plenty of surface to keep coolant from showing up, it has to cover all that area where the jet valve passage is. If its leaking under boost it just sprays out to the bottom. When I say leaking under boost that's when the heat is greater and the rpms are higher and if there's a weak spot the additional pressure from the cooling system is greater that stock boost level so maybe I didn't word that well and it can happen in two ways at the same time. The coolant systems pressure alone can find a weak spot in the gasket at that rear port and then not leak until you drive and get it hot. You smell coolant but you can't find where its coming from? It blows under the car going down the road and is gone. A gasket is just paper, if it gets wet and its loose its gone. It can leak from a runner to that port on the intake flange side but it won't do that on the head side. All you got to do is wipe under there and see if its wet. Coolant takes plenty of time to evaporate that you'll be able to find where it comes from. http://www.b2600turbo.com/images/IM000469.JPG Edited May 17, 2011 by Indiana Link to comment Share on other sites More sharing options...
franco101 Posted May 17, 2011 Author Report Share Posted May 17, 2011 That is very interesting Indiana. At this time I want to remove the head. It's no sweat now being mpi. I can have it off in no time. To many what if's. I want to check block deck, have head checked and milled if necessary. Replace both manifold gaskets.( been wanting to install my new egt sensor anyway). Will look at current head gasket to see if there is any signs of combustion leaking thru. What do you guys suggest I use for an intake gasket. I made my own from gasket material from NAPA but after hearing what Indiana said, I may want to try something else just to be sure. Franco Link to comment Share on other sites More sharing options...
Indiana Posted May 17, 2011 Report Share Posted May 17, 2011 (edited) Since you said its MPI, is that a Magna intake? If it wasn't put on a belt sander to make it flat again yes its warped where that rear port was modified. The very last day Kurt was here he had a coolant leak and thought his headgasket blew so he pulled the head and I told him not to but he was satisfied it was but then when he pulled it off, complete with the intake, the gasket wasn't blown. He hadn't tightened two of the nuts on the intake and using that thick Felpro gasket it lasted a few months then it has started to seep out the coolant and do what I said already. I had put this on a belt sander it wasn't flat at all and was a very big low spot where it was welded up. You can check a stock intake next time you have one off and just put some sand paper on a flat table and slide the intake across it and see how warped they get. http://www.b2600turbo.com/images/IM008509.JPG Part II. Brandon had a coolant leak and on his car he is the one that put the head on and I wasn't around and it was the first time he had did that by himself and he hadn't put a film of oil on the timing cover either where it was milled down for the block and it was leaking oil being messy but that's just good intentions that don't always work out. Although he had driven the car for a year he too thought he had a blown gasket but his compression was fine and it was only leaking when driving. He pulled the head off and this was just a couple weeks ago, and guess what? He hadn't put a film of sealant over either passage on the gasket and right under the intake it had been leaking and it was washed clean and that was using that thick paper gasket and it was effected by the leak. Edited May 17, 2011 by Indiana Link to comment Share on other sites More sharing options...
Tim_C. Posted May 18, 2011 Report Share Posted May 18, 2011 Yes, I'll concurr with Indiana. The intake seal I saw leak was from pressure on the #3 port getting through the gasket seal to the rear coolant passage. It was blowing coolant out beneath the manifold too, just like Indiana says. Not much, and it took a few weeks of driving to see the level in the overflow was low. Link to comment Share on other sites More sharing options...
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