what turbo for 260-270whp

[dan22h]

basicaly i've had some problems with my stroked b16b so i've decided to rebuild it as a turbo engine for a daily driver, i will be purchasing eagle rods with 81.5mm wiseco low comp pistons and acl bearings (will be getting balanced along with the clutch), i will be buying hondata and getting it tuned aswell. I have an ogura racing clutch so that is not a problem
I'm looking for around 270whp

some questions i have
what size turbo for the power? (i don't want loads of lag and i don't want it to run out of puff at the top revs i've been thinking a gt2871r?)
what compresion ratio should i go for?
what make&size injectors?
where's best to get a tubular manifold and down pipe?

my budget is approx £4k but would prefer not to spend more than i have to at the moment

any help appreciated

 

[blinx9900]

For compression and choice of injectors disucss that with your tuner but i would suggest 9.0 or 9.5 and RC 650cc (saturated) or Injector Dynamics 1000cc.

GT2871R is a great turbo, but if you only want 270 then go for the GT2860RS, its the same turbo with a slightly smaller compressor wheel which helps spool up, the 28rs is good for 350whp while the 2871r is good for 400whp, both are great turbo's!

As for manifold you don't really need a tubular manifold for such low power, in fact a log or cast manifold will give better spool up, I know HKS makes a t28 flanged manifold thats cast, keep your eye out for one, or a custom log manifold with a T28 flange.

 

[Chicas]

consider a 9.5 or a little bit higher compression ratio as this will give you very low-end torque.

you can be brave with 10 CR. this will respond more or less like an NA engine but with the top-end of a turbo. the turbo is less stressed also in this setup as you'll be boosting a lot less. if you ever decide on a 10.0:1 CR, then you'd be better off with the GT2871R as it'll be making power more on the top-end.

for injectors you can be safe at 650cc.. I think 440cc would be the minimum, as long as you have a 255lph fuel pump and an adjustable fuel regulator

 

[blinx9900]

you can be brave with 10 CR. this will respond more or less like an NA engine but with the top-end of a turbo. the turbo is less stressed also in this setup as you'll be boosting a lot less.

Turbo's are made to create boost! There is no benefit in running a turbo at a lower boost pressure, ask yourself do you want your turbo to be under more stress or your engine? Boost from the turbo is intercooled, Compression is not, I'd rather have a lower compression engine running more boost, it will be faster and safer and the engine itself will be under less stress. The only time a turbo is stressed is if its boosting past its efficiency range, for a GT28rs that would be anything past about 18psi.

 

[Chicas]

Turbo's are made to create boost! There is no benefit in running a turbo at a lower boost pressure, ask yourself do you want your turbo to be under more stress or your engine? Boost from the turbo is intercooled, Compression is not, I'd rather have a lower compression engine running more boost, it will be faster and safer and the engine itself will be under less stress. The only time a turbo is stressed is if its boosting past its efficiency range, for a GT28rs that would be anything past about 18psi.

I think you don't get what I'm saying.

an engine with 10.0:1 CR @ 10 psi will produce X whp

same engine with 8.5:1 CR @ 18 psi will also produce x whp

where's the difference? smoother power curve on the high-comp engine. with the higher compression engine, you can get a smoother curve eliminating that on/off power curve associated with turbo cars. hence, better traction since the engine won't be solely relying on the turbo.

that's why I was suggesting a bigger turbo. at low-mid rpm, his engine will rely on it's unboosted power. the turbo will kick-in once he's in the upper ranges of the rpm.

a downside here is that if you/your tuner isn't very much skilled, there can be a big risk in damaging your engine. but it's the same thing anyway with pretty much any turbo engine.

just look at how high compression T1's car is running at. it's the new direction for FI cars. with this type of setup + a gear-based tune for boost, traction won't be much of an issue (though it will still be of course)..

 

[kev98sir]

so basically your saying its better to keep higher compression for boostin a NA engine??

 

[Chicas]

yes with the right equipment, tools and knowledge it's better performing

 

[kev98sir]

oh ok. i was always under the impression that yhould take the compression down. im going boostin my ek4 and it has 10.2:1 compression i think. i was going to throw a 2mm head gasket into it to lower compression.

 

[Chicas]

no I'm sorry it's not as simple as that.

I didn't mean to say that boosting a stock block engine is good at boosting (well to an extent, it is).

what I meant was that since the thread starter stated that he was going to fortify his block anyways with forged pistons and rods, he should get the higher compression pistons.

 

[ALEX-CY]

Turbo's are made to create boost! There is no benefit in running a turbo at a lower boost pressure, ask yourself do you want your turbo to be under more stress or your engine? Boost from the turbo is intercooled, Compression is not, I'd rather have a lower compression engine running more boost, it will be faster and safer and the engine itself will be under less stress. The only time a turbo is stressed is if its boosting past its efficiency range, for a GT28rs that would be anything past about 18psi.

i angre with blinx, thats why all factory turbo cars use 9:0-9:3 cr(evo-sti...)
if you want reliability go with low cr

 

[blinx9900]

no I'm sorry it's not as simple as that.

I didn't mean to say that boosting a stock block engine is good at boosting (well to an extent, it is).

what I meant was that since the thread starter stated that he was going to fortify his block anyways with forged pistons and rods, he should get the higher compression pistons.

See this is the problem, you start telling people to do it, its the new way, its better, but you don't tell them how spot on the tune has to be, how precise everything bust be, and if there is one mistake, one tank of crap gas, BOOM!! Bye bye engine, i have had a 10.8:1 turbo motor and now i have a 8.3:1 turbo motor so i do have experience with both, high comp + turbo is not as amazing as you think.

Furthermore you ABSOLUTELY cannot bring a racecar into this discussion (tony's car), racecars run on RACE GAS! The AEM drag civic has 11.5 compression and made over 1200whp but who cares, we are talking about a 250-270whp setup for the street.

an engine with 10.0:1 CR @ 10 psi will produce X whp

same engine with 8.5:1 CR @ 18 psi will also produce x whp

surely you don't really think 1.5 point in compression has the same effect of adding 8psi?

There are many things wrong with your statements, you make it sound like its so easy but the truth is that ITS NOT!

Tell me sir, do you personally have a high comp turbo setup or are you just quoting other peoples experience? I don't mean to be rude but this is how people end up with blown motors, they see someone giving advice, making it sound all easy, little to they know the car is tuned to the edge and can blow up with the slightest mistake.

 

[Chicas]

See this is the problem, you start telling people to do it, its the new way, its better, but you don't tell them how spot on the tune has to be, how precise everything bust be, and if there is one mistake, one tank of crap gas, BOOM!! Bye bye engine, i have had a 10.8:1 turbo motor and now i have a 8.3:1 turbo motor so i do have experience with both, high comp + turbo is not as amazing as you think.

Furthermore you ABSOLUTELY cannot bring a racecar into this discussion (tony's car), racecars run on RACE GAS! The AEM drag civic has 11.5 compression and made over 1200whp but who cares, we are talking about a 250-270whp setup for the street.

I'm sorry if it sounded too easy, but I WAS ASSUMING you guys have excellent tuners and have access to alot of technical knowledge there because I live in a 3rd world country, where as in you people live and 1st or 2nd.

I don't know about you but I had a great experience with high-comp turbo setups. I personally had 10.0:1 CR Arias on a B16B block with 89 crank. It produced 412whp @ only 13-14 psi on a GT35R sized turbo. It produced less 60-foot times than an almost similar engine (only difference is in cam and an 8.8 something CR) with the same horsepower. I sold it to a friend who melted a piston, thinking that more response can be had by just adjusting the distributor. So yes, I have personal experience.

surely you don't really think 1.5 point in compression has the same effect of adding 8psi?

There are many things wrong with your statements, you make it sound like its so easy but the truth is that ITS NOT!

Tell me sir, do you personally have a high comp turbo setup or are you just quoting other peoples experience? I don't mean to be rude but this is how people end up with blown motors, they see someone giving advice, making it sound all easy, little to they know the car is tuned to the edge and can blow up with the slightest mistake.

It was an example. YOU SHOULD KNOW that my point was two different engines producing same horsepowers but with different curves. Don't talk to me like I'm some noob who just happens to pass by here. Produce cars first that makes 400+ whp before you look down on other peoples opinions and experiences. Traction isn't much of an issue with your 300++ whp as much as it is in 400whp and above.

Yes I admit I talked too little about the dangers with respect to tuning and whatnot. But I assumed that you people have lots of access to excellent tuners with better equipment than us here. I admit that I posted too late about that. So for that, I'm sorry. But I still stand by my opinion based on my experience. Don't worry, I won't be posting in this section anymore.

 

[blinx9900]

Chicas most people on this forum are not from USA, yes we do have excellent tuners here in USA and tuning high comp turbo cars has become very simple and easy here because it has been done so many times, but as i mentioned, most people here are not in USA, most people are from countries where they have a hard enough time finding a good NA tuner, let a lone someone who can tune a high CR turbo setup.

And believe it or not, i probably have more traction problems than you do, GT3076R is a very fast spooling turbo and probably the worse choice for drag because of the violent spool up, i spin past half track with Nitto NT01 tires Most people i know opt for the 35r because it spools a little higher up in the powerband where there is more traction.

I know what your saying, and your not wrong in most of what you say, its just a bit over the top for most people who just want a simple street setup, almost like if someone asked what suspension they should get for a street car and you suggest something like cantilever suspention retrofit. Yes it could and would work if setup properly, but is beyone most peoples understanding and ability.

At the end of the day we all have our personal taste and opinions, and thats what sets us apart and makes this forum great, sorry for coming off so harsh

 

[Chicas]

Chicas most people on this forum are not from USA, yes we do have excellent tuners here in USA and tuning high comp turbo cars has become very simple and easy here because it has been done so many times, but as i mentioned, most people here are not in USA, most people are from countries where they have a hard enough time finding a good NA tuner, let a lone someone who can tune a high CR turbo setup.

Well that I didn't know of. I was thinking we (here) probably have the least number of good tuners in the Phil. On top of my head, there are only 4-5 names that pop up that have proved themselves time and time again and whom I really admire and wish to be some day..

And believe it or not, i probably have more traction problems than you do, GT3076R is a very fast spooling turbo and probably the worse choice for drag because of the violent spool up, i spin past half track with Nitto NT01 tires Most people i know opt for the 35r because it spools a little higher up in the powerband where there is more traction.

I exactly know what you are saying. That's why I was telling him (thread starter) to go to a bigger turbo even if just boosting it so little just to achieve his goal.

I know what your saying, and your not wrong in most of what you say, its just a bit over the top for most people who just want a simple street setup, almost like if someone asked what suspension they should get for a street car and you suggest something like cantilever suspention retrofit. Yes it could and would work if setup properly, but is beyone most peoples understanding and ability.

At the end of the day we all have our personal taste and opinions, and thats what sets us apart and makes this forum great, sorry for coming off so harsh

Yeah because I was thinking, again, about the excellent tuners and equipment. Okay but please next time be a bit more 'cautious' (?) because the way I interpret it, you think of me as some kid from YouTube who comments alot thinking he knows everything. I'm setting this straight right now, I don't know everything, but I do know my experiences. I know I typed like an ******* in my previous post. Some lines were quite uncalled for I'll refrain from doing it again, as this great forum might turn into something like Honda-Tech...