How much Boost

[Bulldogger]

Coming from other boosted applications I assumed we would be talking about good tuning. Next knock shouldn't be that big of an issue if the timing isn't pushed along with boost levels. I wasn't interested in how much horsepower the truck can make more along the lines of how much boost the rods and ringlands can handle. If I know the boost level then I can make adjustments from there. I have a tendency to work things backwards. My GT500 can run on race fuel but I don't choose to go that route. Anything at or over 18lbs really is cam 2 territory. I choose my VMP TVS based on the fact that it makes just under 18lbs actually about 17.5 on stock exhaust. Throw on Dynatech LT's and catless pipes, I am at 16lbs of boost, with a 17* of timing and 93 octane I am still in a conservative safe area, with 680 rwhp.

As far as which route I will go TRD will more then likely be the more difficult route as far as cooling the IAT and getting parts for it, but the reflash ECM can't die independently causing issues, like a piggy back system. My experience having both is twin screws/roots are more fun stop light to stop light but suffer form heat soak and fall off up top. Centrifugal can lack a litlle out of the hole but are alot less prone to heat soaking and do much better up top. Plus URD seems to have everything in one spot shopping which is nice.

X-roller he doesn't list any supercharger options with his kit. What changes he has made in the past well I lost my crystal ball. Searching this forum and the URD site only seemed to show the MKII units with different stage upgrades, like stage I to II to III. All head units are the same on his web page. When you do other boosted cars there are alot more options on head units. Example GT500 you can run a TVS 2.3l or a whipple 2.9 or 3.4 or 4.0, you can also run KB 2.8 2.8l or 3.6 plus fords version of the TVS eaton.

 

[Bulldogger]

Yes but its important to specify the conditions of use and what power adder you are talking about.

A motor that sees more race hours will fail WAY sooner then a motor who sees mild DD driving.

Furthermore boost related to power increase is not really the best way to determine engine reliability; you should be asking how much power can this engine handle then start looking at compressor efficiencies / designs that fit the criteria you set.

Not all power adders introduce more power the same way, peak horsepower numbers do not reflect engine stress very well.

Nitrous or a TRD blower or a Turbo that is sized correctly can introduce a lot of torque instantly; this is what is going to break stuff eventually vs. the more gradual building power delivery of a centri blower.

Specifying no knock is also important as most do not understand the significant nature of the statement; if you understand that just a little knock due to w/e reason can severely deteriorate any engine life you had on the table then ok.

With a perfect tune under all temperatures, under all driving situations, with great fuel you can still have knock related engine failure due to other influences.

A little knock will not kill a stock power N/A engine, but it will destroy a 400 HP 1GR in a hurry...

It's worth mentioning since how much power you can produce for how long will be directly related to how you drive it and how much knock exposure you let it have.

The whole how much boost can the engine take question is just a generic worthless question at best.

I understand what you're saying, but what I was after was just a simpler answer like 8-10 lbs is safe 12lbs is pushing it and 15psi the plenums break. This is basically all I need to start addressing the build.

This was my sole reason for the first post, just an idea of component related strength.

As far as knock goes I understand what your saying but if the Tune is good, you shouldn't be getting knock, unless the fuel pump gets weak or an injector starts to clogs or you get bad gas these things are variables that non of us can control or predict. As far as longevity goes I also realize beating it or flogging it will greatly effect the outcome but these are also realitive terms to the individual. I jump on my mustang every so often, smoke the tires shift at 6200rpm, but according to my friend I drive it easily, comming from a guy who hole shots his at 5500rpm and constantly hits the rev limiter which he raised to 6500 with the SCT tuner. To me thats just abusive behavior so again this is realitive to the individual.

Anyway I did get the answers I was looking for:top:

 

[Torspd]

If you want to swap compressors with the MK kits, all that is necessary is to make the call to Gadget at URD. There are plenty of members running 10 psi on either setup. Some run E85 as well with the 7th injector to help with the cooling aspects you mention. Been running like that for quite a while as well.

Either way, it all comes back to the tuning. Gadget has been extremely helpful with his customers keeping their tuning safe. If you know how to tune your choice of EMS well, you can do that as well to keep it as safe as you like. For the money, the MKIII will net you the higher power overall.

The UCON that is on the market for kits, and will be shortly for everyone else soon, will be the best bet. Unless you have an 09 +. Then that will be a little longer until a plug n play harness is ready for those year models. If you don't mind splicing, then you have other options as well.

I have a really safe tune on my ProEFI and at 8.7 psi I had just about 400 whp as well, on my setup. Would have lasted for ever. I like to push the envelope though. That is a another story though.

 

[Torspd]

The ring lands are the weakest link. Then the rods. The ring lands simply cannot handle much knock with boost. 8 psi +.

I have run 14.8 psi for quite a while on my stock intake manifold. In my experience with this motor, I have learned that there are some similarities between it and the Nissan VQ motor.

Point is, that their plenums have been known to split around 18+ psi. Once my motor is freshened up and back in, I am going to test that to see where our stock one gives.

 

[Bulldogger]

I am probably just gonna stick with 8-10 psi. Longtubes and hiflo exhaust and call it a day. Not looking to go crazy. Just something fun and more practical then what I have. I have been looking for 2005-08 low mileage truck in red or blue. I'm too old and tired to be dealing with black. Spoke to Gadget probably will end up with stage II kit or stage I with full exhaust.

 

[X-roller]

Coming from other boosted applications I assumed we would be talking about good tuning. Next knock shouldn't be that big of an issue if the timing isn't pushed along with boost levels. I wasn't interested in how much horsepower the truck can make more along the lines of how much boost the rods and ringlands can handle. If I know the boost level then I can make adjustments from there. I have a tendency to work things backwards. My GT500 can run on race fuel but I don't choose to go that route. Anything at or over 18lbs really is cam 2 territory. I choose my VMP TVS based on the fact that it makes just under 18lbs actually about 17.5 on stock exhaust. Throw on Dynatech LT's and catless pipes, I am at 16lbs of boost, with a 17* of timing and 93 octane I am still in a conservative safe area, with 680 rwhp.

As far as which route I will go TRD will more then likely be the more difficult route as far as cooling the IAT and getting parts for it, but the reflash ECM can't die independently causing issues, like a piggy back system. My experience having both is twin screws/roots are more fun stop light to stop light but suffer form heat soak and fall off up top. Centrifugal can lack a litlle out of the hole but are alot less prone to heat soaking and do much better up top. Plus URD seems to have everything in one spot shopping which is nice.

X-roller he doesn't list any supercharger options with his kit. What changes he has made in the past well I lost my crystal ball. Searching this forum and the URD site only seemed to show the MKII units with different stage upgrades, like stage I to II to III. All head units are the same on his web page. When you do other boosted cars there are alot more options on head units. Example GT500 you can run a TVS 2.3l or a whipple 2.9 or 3.4 or 4.0, you can also run KB 2.8 2.8l or 3.6 plus fords version of the TVS eaton.

MKI is no longer made. MKII and MKIII should be on his website. I'm sure he can upgrade your blower if you asked when purchasing the kit. :top: It's your choice though. As torspd stated though no one has really reached a PSI limit related issue it's more just tuning or power level. I may beat him to it on the psi level though. I'm planning on pushing this plenum till it breaks or I feel comfortable with it. I too will be pushing around 15+ psi. :biggrin:

 

[Bulldogger]

MKI is no longer made. MKII and MKIII should be on his website. I'm sure he can upgrade your blower if you asked when purchasing the kit. :top: It's your choice though. As torspd stated though no one has really reached a PSI limit related issue it's more just tuning or power level. I may beat him to it on the psi level though. I'm planning on pushing this plenum till it breaks or I feel comfortable with it. I too will be pushing around 15+ psi. :biggrin:

Actually then the engines are pretty durable. Like I said I will be sticking 8-10lbs and with good tuning should make for a very reliable ride.

I actually should have clarified my first post with, what is the standard boost level from the URD and TRD base kits and have there been any related issues at that boost/horsepower level. Wasn't trying to get answers with different cams or porting and polishing or anything of that nature. Just standard kits that were sold. My bad. Still all in all got great answers. Now to find a truck:rockon:

 

[X-roller]

Actually then the engines are pretty durable. Like I said I will be sticking 8-10lbs and with good tuning should make for a very reliable ride.

I actually should have clarified my first post with, what is the standard boost level from the URD and TRD base kits and have there been any related issues at that boost/horsepower level. Wasn't trying to get answers with different cams or porting and polishing or anything of that nature. Just standard kits that were sold. My bad. Still all in all got great answers. Now to find a truck:rockon:

Well I wouldn't go that far... Me and Torspd have internal work done... I have forged rods and pistons plus some minor head work with cometic head gaskets and he has low comp pistons and other goodies as well. :top:

 

[cwatt]

Out of curiosity, what would break first? Intake, pistons, rods,...? Perhaps I should phrase the question as, for high-boost applications, what should I look to upgrade too?

 

[blackx-runner]

Out of curiosity, what would break first? Intake, pistons, rods,...? Perhaps I should phrase the question as, for high-boost applications, what should I look to upgrade too?

The ring lands are the weakest link. Then the rods. The ring lands simply cannot handle much knock with boost. 8 psi +.

I have run 14.8 psi for quite a while on my stock intake manifold. In my experience with this motor, I have learned that there are some similarities between it and the Nissan VQ motor.

Point is, that their plenums have been known to split around 18+ psi. Once my motor is freshened up and back in, I am going to test that to see where our stock one gives.

Pistons and rods would be the first think you would want to upgrade.

 

[X-Run-X-er]

TRD S/C runs around 6 psi stock, and toyota always gives us alot of room for error to cover there butts, I would say 8 lbs is effecent yet dependable in the long run, just my take :rolleyez:

 

[cwatt]

Pistons and rods would be the first think you would want to upgrade.

Thanks. I had a feeling that was the case.

If anyone cares to save me some 'search' time, what have people done in the past for this? Preferences on pistons? etc.


thanks again...

 

[Torspd]

Here is the link that will guide you to all of your answers.

http://www.lceperformance.com/SearchResults.asp?Search=1gr&Search.x=14&Search.y=7

I ordered a set of 9.2:1 compression pistons through them. Best thing to do, is save that website, and call them when ready with your questions.

And trust me, going somewhere else to try to find parts and at a cheaper cost, will increase the potential for problems ten fold.

 

[X-roller]

Here is the link that will guide you to all of your answers.

http://www.lceperformance.com/SearchResults.asp?Search=1gr&Search.x=14&Search.y=7

I ordered a set of 9.2:1 compression pistons through them. Best thing to do, is save that website, and call them when ready with your questions.

And trust me, going somewhere else to try to find parts and at a cheaper cost, will increase the potential for problems ten fold.

Learned by experience.

 

[cwatt]

Here is the link that will guide you to all of your answers.

http://www.lceperformance.com/SearchResults.asp?Search=1gr&Search.x=14&Search.y=7

I ordered a set of 9.2:1 compression pistons through them. Best thing to do, is save that website, and call them when ready with your questions.

And trust me, going somewhere else to try to find parts and at a cheaper cost, will increase the potential for problems ten fold.

Thank you! That website looks great.

A question though, why not order the higher compression pistons (i.e., 12:1)? Isn't that the name of the game here - more compression?

 

[hottacoX]

Thank you! That website looks great.

A question though, why not order the higher compression pistons (i.e., 12:1)? Isn't that the name of the game here - more compression?

Our block on the 1GR is an open deck design, and from what I gather increasing the conpresson greatly increases the chance and blowing up the block. To do so safely you would have to get the block sleeved at Darton. I think there are now maybe 2 or three members that have a sleeved block.

There are other issues as well when raising the compression but it not comming to mind right away lol

 

[Torspd]

Thank you! That website looks great.

A question though, why not order the higher compression pistons (i.e., 12:1)? Isn't that the name of the game here - more compression?

On an N/A motor yes. That is one easy to make more power. On a boosted motor, no. Within reference, say 10:1 compression, higher compression ratio will also increase knock potential, and decrease the knock threshold. Thus when adding boost, which in turn fills the combustion chamber with extra gases, that have to be compressed into to same area as before when it was N/A, you don't want the higher compression piston. At that point you would decrease the knock threshold even further. (This of course all being on a gasoline motor, and relative to components strengths.) Thus the knowledge gained over many many years of testing by engine builders abound, has resulted in the proof that lowered compression for a boosted motor is the smart, safe, and mathmatically sound way to build a boosted motor.

Plain and simple, a lower compression piston is safer. How low to go? Depends on how much low end power you are willing to sacrifice, coupled with the amount of rpm it takes to surpass the boost threshold of your F/I setup. A turbo in most cases will have a higher boost threshold than a positive displacement blower.

 

[Bulldogger]

In addition to all this the quality gas you get in your area can be a major factor. Several higher boosted guys thought it was safe to run above 18 psi on the Mustang forum and now have windowed blocks and holes in the piston golf balls could pass through. When tuning and boosting you rally need to be careful of the ACTUAL octane rating. Several stations out where I live are putting 87* in the 93* pumps plus you can not exceed 18psi on regular pump gas you need race fuel.

 

[Torspd]

Ouch.

I will mention this, Butters had his MK3 tuned to 15 psi, on his stock block. Made 450 whp and 400 wtq. On 93.

 

[Bulldogger]

Ouch.

I will mention this, Butters had his MK3 tuned to 15 psi, on his stock block. Made 450 whp and 400 wtq. On 93.

Unfortunately this is happening all too often. I am at 16psi, on a 91* tune with only 16* degrees of timing max. I also always put 93* octaine in from a major company like Sunoco or Mobil. I'd rather stay at 670-680rwhp then blow the motor at 720rwhp.

The ways to help compensate for the crappy fuel is to run meth as a safety. Don't tune for it to make power use it as a cooler and octaine boost or switch over to e-85.