My 2nd split wall.....

[evolutionmovement]

Tulips! Nice, now that spring is here.

[SLODRIVE]

Open deck blocks can and do make much more power at similar boost levels. Therefore the pressure ratio isn't very relevant. The absolute pressure doesn't matter nearly as much as the mass of the air in the cylinder. Without a temperature, the pressure is pretty much irrelevant.

Not trying to flame, but are you sure you worded all this correctly? Pressure ratios and absolute pressures are FAR more important than the mass of the air in the cylinder. The only reason to try to increase the mass of the air in the cylinder is to increase cylinder pressure. The temp isn't really important until the pressure goes way up either.

I'm not going to get into the open/closed deck power argument because...well, because that's a story better proven by results than speculation.

[93forestpearl]

^ Maybe not worded the best?

What I'm saying is that 30 psi relative from a T04 is not the same as 30 psi GT4088R, but not that far apart in the grand scheme of things. The resulting compressed pressure will be vastly different, since the turbos will be at different efficiencies and temperatures.



All I'm trying to get at is that manifold pressure is a small variance (based on turbo selection) compared to the delta from detonation. We're talking tens of psi vs. thousands of psi.

[ciper]

I fully agree with 93forestpearl's previous post. I also think that douglas vincent knows what he is doing.

Who knows, this 2.5 block may have been damaged previously (overheating?) or had a manufacturing flaw.

http://bbs.legacycentral.org/viewtopic.php?f=11&t=43071 shows just about 280hptq. At most thats 360 crank at 22 psi with a "leaking headgasket" which was probably the beginning of the crack.

[douglas vincent]

Personally, I am 100% certain that #4 cylinder is the weak link ALWAYS. EVERY split cylinder, unless the extra split cylinder is in CONJUNCTION with #4, has been #4 for all the blocks I have seen personally and internet wise.....

And again, PERSONALLY, I am pretty damn sure I damaged it when I did an uphill pull and knocked the fuck out of it when I overboosted while still running 92 octane.... Damn smartypants MR2s!!!!!!

[93forestpearl]

Personally, I am 100% certain that #4 cylinder is the weak link ALWAYS. EVERY split cylinder, unless the extra split cylinder is in CONJUNCTION with #4, has been #4 for all the blocks I have seen personally and internet wise.....

And again, PERSONALLY, I am pretty damn sure I damaged it when I did an uphill pull and knocked the fuck out of it when I overboosted while still running 92 octane.... Damn smartypants MR2s!!!!!!

LOL, the kids on the street always always provoke, don't they?




Doug, do you think your consistent issue with that cylinder is a fuel delivery issue or otherwise?


I ask because a parallel setup like mine can be done for way less, after I learned the hard way. Three adapters from Outfront, and after talking to an industrial Aeroquip dealer will make it happen. After a conversation I had a few days ago, I am still kicking myself for using the braided crap since it is expensive and stupid. The Push-Lock stuff is so much easier and cheaper. The extra three pounds from steel fittings is trivial.

[Kelly]

I remember when Marc Lien cracked the #1 or #2, cant remember which but it was a foreword hole.

He poured cold water into it when it over heated.

[93forestpearl]

I like working on the top holes as opposed to the bottom ones.....



Wait, wut?

[douglas vincent]

I doubt fuel delivery was the problem, other than maybe not enough..... Now that I am running E85, I don't have issues to speak of.....

[93forestpearl]

Well, not enough fuel is kind of the point of me asking. E85 requires 25-30% more fuel flow, so if you had issues with pump gas, you will have more issues with corn.

[douglas vincent]

Well, I mean I may not have had enough for the boost spike. and now with the rrfpr, I do have more than enough capabilites for the E85.

[Kelly]

Well, I'd like to start a sentence with "well" too!

[93forestpearl]

[douglas vincent]

Thats what I try to keep inside the motor!

[smh0101]

Well doug... I have to say.

Job well done! If you blow it up! Blow it up right! lol

At least now you've got another paper weight! hahahaha

[Legacy777]

Other thing I've heard about #4 cylinder is that the exhaust port from the head is the most restrictive on cylinder 4, which could also lead to problems. Not sure how much validity that comment has, but something I heard.