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I am about to buy new pistons rods and injectors. I got a damn good deal on a set of 8.5:1 pistons and AEM hyper rods. i forget what pistons they are, but i think that they arias or something like that. i was wonderingif 8.5 is too low for a daily driven honda. i was also wondering what the advantage of blockgausrd are versus re-sleeving the cylinders. i want to do it right and dont care how long it takes, i just want the damn thing to run effeciently. Also do you think that 310cc injectors are enough for the task? i just want to be a really fast daily driven car. not interested in full drag racing, but want to keep up with the supras around here. also, do you think that the profec b is a good boost controller, or should i use the apex avc-r? i also had pms in mind, but notsure if anyone has used it or is using it please give some feed back. last question, does anyone know the price of that 35mm tial wastegate, or does someone want to start a group buy? thanks for your help in advance.
daniel
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forgot to mention that this is a 94 integra gsr, with a nos fuel pump, t3/t4 turbo, f-max intercooler and piping, greddy PE, ACT clutch, and vortec fmu.
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It's is a little low.. you could correct it with a tad thinner head gasket.. I would suggest 9:1, I'm installing 10:1 on my turbo, it's being resleeved as well.. I would suggest resleeving, you will not overheat as easily, they say "well we never seen the temp guage move with blockguard." If you don't forget, it takes a tad bit of heat to make a honda guage move, so yes you will be running hotter, I don't care what they say.. and you will overheat easier. Also Blockguards just keep the top of the sleeves more stable, what about the inbetween the top and the bottom? Where the most pressure in the combustion chamber exits? As you may know the mixture's highest pressurized point is not at the top, it's in the inbetween.. as well as your 1.58 rod ratio, most pressure is also moved more towards the sidewalls.. So though you could get away with running a blockguard, your beating your engine much more by not resleeving it. Or taking other measures to better equalize the loads on the walls.. I would also suggest you ask your engine builder to move the rings on the pistons up the most he could, and order a custom set of rods, just to give you a tad better rod ratio, as every bit counts, prolly end up somewhere around 1.62.
Bryan
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Bryan,
Please explain your reasoning on why you should move the ring-pack up further on the piston. I understand why you would want to move the whole ring-pack/wrist pin up to get a better rod/stroke ratio, but moving the ring-pack up also exposes it to more combustion chamber pres. This is one of the faults of stock Honda pistons and why they tend to fail under boost. After market pistons move the ring-pack further down on the piston skirt almost over the wrist pin to isolate it more from the extreme cyliner pressures. Maybe you know something I don't?
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Mark - Darth Boost - Turbo Mafia
98 Pearl Black GS-R, DRAG Gen. 3 Turbo
13.2 at 114MPH (GTech/Pro w/Drag Radials)
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The highest cylinder pressure, not to be confused with side thrust, is at the top just after the pistons have past TDC. Detonation stresses the walls the most at or near TDC as well. I don't think the blockguard will cause the coolant temp to run higher, it will just cause the cylinder walls to run hotter at the very top where they need the most cooling.
Swapping head gasket thicknesses has to be done carefully in conjunction with piston config so proper quench (squish) clearance is maintained.
I also understand that compression rings survive longer when placed lower on the piston; farther from the heat and possible detonation stress.
[This message has been edited by rjaffey (edited February 17, 2000).]
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Pushing the ringpack higher also pushes the ringpack closer together which reduces the size of the ring lands. Also not good.
I would stick to stock Honda geometry unless you are 1fstgsr and have something spicey planned. http://www.hostboard.com/ubb/biggrin.gif
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Mark - Darth Boost - Turbo Mafia
98 Pearl Black GS-R, DRAG Gen. 3 Turbo
13.2 at 114MPH (GTech/Pro w/Drag Radials)
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8.5:1 is just fine. It'll give you a much bigger tolerance for tuning. Lower compression means you won't detonate nearly as easily. It's just not a problem driving with a lower compression ratio. Turbo may spool a little slower, little less power but you can run more boost. 10:1 compression on an FI engine doesn't seem wise, unless you're only going for a small amount of pressure or you never run on street gas.
As for the block guard, might as well just do both. I could have sworn my block guard went around all of the cylinder, not just the top/bottom.
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Ryan Earl
'99 Turbo SH
NTPOG - North Texas Prelude Owners Group
My Page
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the new super street has a documented installation of a block guard. seems to only help solidify the top of the cylinder walls.
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My 'teg seems to know when i have $$, how bout you?
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so basically it would be better to re-sleeve the cylinders? who sells the sleeves? i cant seem to find anybody who sells them. i havent tried real hard either. should i get new head studs? someone mentioned them to me but not sure the purpose. and will 310cc injectors be big enough or should i get bigger ones?
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Actually MarkC if you were to read it more carefully you would see I said to contact the manufactur to get a idea of how much you can safely move it up.. It doesn't terribly hurt things, as you would be moving it up as much as is safely possible.. Honda rings are actually pretty well spaced, if you were to speak with many builders you would see they do not go past the stock ring locations 99% of the time unless they have a real reason to.. Honda engines fail underboost for one reason, they were not built as performance engines they were built as effiecent engines, not something to slap 10 psi on.. and expect it to last.. so you should realize that. Only way you will get a better rod ratio without destroking or adding to the block is to move the ring package up.. that improved rod ratio would help you more than putting the strongest rods or pistons in there.. as you would see has been done on many cars with terrible rod ratios as the b18..
Bryan
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You yourself will not be able to put in the sleeves.. I would only suggest having a engine builder do this.. which will cost around 900$, Bensons sells sleeves for the b18..
bryan
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Think of it this way.. slower piston speeds = less wear on rings = less ring failure = able to move ring package up safely. Over all happier engine...
Bryan
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Chrysler used a 8.5:1 in their production turbo cars. There is nothing wrong with that compression ratio.
You can run at high boost and off boost gas mileage will be very good.
If you are getting custom slugs with that compression, I would get some that have clearances for the valves in case the timing belt breaks. This way you won't trash the valves.
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'96 JR6 GSR Sedan
'93 Honda CBR 900RR
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4Sale:New Holley 255 fuel pump kit
#12-906 (Integra/civic)
$200 shipped COD
[This message has been edited by plumvtec (edited February 18, 2000).]
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has anyone here dealt with bensons? how reliable are they and is their work warrantied? I just dont want the engine to fail on me down the road. and if re-sleeving the block will help prevent this then i am willing to pay the money. also, has anyone heard of eagle rods? i found out about them today and they are cheap, but i am weary of them because i havent heard much about them. also how big of a fuel pump will i need to run a max boost of 17psi? how big of injectors?
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a better rod ratio is always better, becaue there is less pistons speeds at high RPM. This will not necessarily make the engine more reliable, it jsut helps. For simplicity sake, a good rebuild for 10-15psi at track and 8-10psi on street is a set of forged pistons, stronger rods (with accompanying bolts), stronger head studs, stronger (i.e. S/S exhasut valves), adequate engine managment to NOT go aggressive with ign timing (as stock Honda tables tend to be because it was designed for N/A), adequate fuel supply (so bigger injectors and fuel pump equipped to supply the injectors) and stiffer valvesprings.
The stock Honda sleeves are strong enough to withstand the boost, many tuners bosot higher than 24psi wiht the stock sleeves and block guard (unwelded, i.e. NuFormz).
The Blockguard IS highly recommended and is only needed to hold the open deck of the block together. Obviously it would be better to utilize a more solid deck but NOT necessary. The block guard does not cause overheating of the cooling system, nor does it cause stress marks at the top of the inner cylinder walls.
When all is said and doen, you're lookign at $10K to get a very reliable turbo car; this price not including the price of the block.
Greg-
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How does changing your rod:stroke ratio reduce piston velocity? Reducing your stroke will reduce piston velocity. Reducing your rod:stroke ratio will reduce sidewall loading and change the dynamics of your internal components(more dwell time etc.).
If you have 1797cc displacement with a 81mm bore and 87.2mm(?) stroke your piston velocity will be the same at any given engine RPM with a 1.58 rod/stroke ratio or a 1.75 rod/stroke ratio. If you keep the same displacement without changing bore and stroke sizes the only way to increase the rod/stroke ratio will be to get a longer rod. The angle the rod makes with the piston will be more perpendicular with a better rod/stroke ratio, but the piston is still moving that 87.2mm every stroke at the same rate(RPM) regardless of the rod length.
Maybe you guys are confusing how the B16A has much better piston velocities at high RPMs and a near optimum 1.74 rod/stroke ratio. The rod/stroke ratio isn't responsible for the lower piston velocities, it's the shorter stroke the engine uses.
Or am I missing something here?
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The average piston speed is determined by the stroke and RPM. However, the maximum piston speed increases as the rod/stroke ratio decreases.
[This message has been edited by rjaffey (edited February 19, 2000).]
