WHy can imports handle more boost

Why can imports handle more boost than our cars with the stock bottom end they can handle more and even when both are modified you always see imports running more boost than domestics.

most of them came turbocharged from the factory, which means they came with lower compression, and forged internals.

put the same parts in a domestic and it can handle the same boost, as long as the engine is properly built.



another point of interest.........imports rev super high without probs

im guessing this is due to having overhead cams instead of a pushrod design........maybe OHC is better suited to reliable high rpm use.

So lets just say i built a fully forged best parts 396 with low compression how much boost can it handle with 93 octane

Originally posted by zuluman13
So lets just say i built a fully forged best parts 396 with low compression how much boost can it handle with 93 octane

as long as everything is done right (engine, fuel, tuning)...........id guess whatever the gaskets can handle.

but someone with more knowledge/experience will be able to give you a better answer.

A factory forced induction car almost always can handle way more boost than our stock bottom ends. That isn't just an import thing.....think of Syclones/Typhoons, 03 Cobras, GN/T-Types/20th Anv. Turbo TA's, Lightnings, etc.

As for reving high, it has partly to do with their valvetrain setup, and also to partly to due w/ a shorter stroke design. But even then, I know of some pushrod motors that rev quite high. Have a buddy w/ a 355 that VERY regularly spins his motor to 8000 RPM, even on the spray. Solid roller cam.

rob raymer, running 25lbs of boost all day (http://www.ls1.com/forums/showthread.php?s=&threadid=393293)


whats funny is.........imports + 25lbs boost = 12's, maybe 11's

domestic + 25lbs boost = 9's, maybe 8's.

Depends on the breathing.. stock V6 turbo motor with 25 PSI makes 475 RWHP on 93 with alky injection. Do heads, cam, intake, intercooler..etc..same power at 15-16 PSI.

Breathing..boost is a restriction..open the bottle necks..watch out :D

Original question..lower compression..

Watch that octane requirement.. its a doozy if ya detonate at HIGH PSI :bow:

Originally posted by got_hp?
rob raymer, running 25lbs of boost all day (http://www.ls1.com/forums/showthread.php?s=&threadid=393293)


whats funny is.........imports + 25lbs boost = 12's, maybe 11's

domestic + 25lbs boost = 9's, maybe 8's.


I hope you arent including DSM to that list, if you are then you are ignorant. A certain PSI doesn't equate to a certain time. Perhaps it was just a joke, if so don't quite your day job.


Michael

Originally posted by boostedinaz
I hope you arent including DSM to that list, if you are then you are ignorant. A certain PSI doesn't equate to a certain time. Perhaps it was just a joke, if so don't quite your day job.



holy crap.........someone hurry..........we need the jaws of life...........this guy has his panties wedged too far up his butt

calm down man.............im speaking of the typical rice rocket crap thats out there running big boost and making pathetic ET's.

trust me, i have mucho respect for the DSMs out there that know how to put the power to the ground..........i almost bought one myself.

Originally posted by got_hp?
rob raymer, running 25lbs of boost all day (http://www.ls1.com/forums/showthread.php?s=&threadid=393293)


whats funny is.........imports + 25lbs boost = 12's, maybe 11's

domestic + 25lbs boost = 9's, maybe 8's.

Titan motorsports supra runs 8.8@169 on drag radials ;)

Duane

Originally posted by upgradedsupra
Titan motorsports supra runs 8.8@169 on drag radials ;)

Duane

yes i know, its the holy grail of all the import/supra guys.

Titan is really not that fast compared to Paul from MSP. They went a 8.255 @ 170.90 this past weekend at E-town.

Jose

Originally posted by JZ 97 SS 1500
Titan is really not that fast compared to Paul from MSP. They went a 8.255 @ 170.90 this past weekend at E-town.

Jose

on bfg's or slicks?

I, myself, dont like supras, but this does tickle my fancy.



Go fast here (http://www.shepracing.com/pictures/shep8944low.wmv)

On QTP's

Michael

Originally posted by got_hp?
on bfg's or slicks?

BF Drag radials.

Duane

Thats on BFG's. Thats the same car that won the BFG drag radial war shootout with the top turbo domestics...including Big daddy. Those darn 2JZ-GTE's are insane motors. Only reason why I bought one, and also they look pretty cool ;) . The stock motor record was broken this past week also it was 954rwhp, now its 980rwhp through an auto tranny :eek: .


Jose

Originally posted by upgradedsupra
Titan motorsports supra runs 8.8@169 on drag radials ;)

Duane

Kenny duttweiller's TT 4.5L stage 2 Buick V6 just pulled over 1600rwhp and blistered the 1/4 with a 6.90 @200. ~40lbs of boost from intercooled twins. Yes it was on slicks, but tell me something.... where's a drag radial that won't explode from that kind of power? He also built a TT 502 BBC that makes over 2500hp and idles like your average mild-cammed small block. And i can name about 10 turbo6 buicks right off the top of my head that make over 1000rwhp.

See where i'm going with this? It's not an import thing... it's the technology at hand and how you use it. A 350 cubic inch V8 pushed by 25lbs of boost will make a HELL of a lot more power than a 4 banger at a 1/3 of the displacement at the same boost levels. Plus the bigger engine, in most cases, will be able to handle more boost/power before block destruction occurs. Why try to make 2000hp with a block that is known to split at 1000hp? There is a point of sensible practicality.

But back to the import thing, I'm guessing since their parts and such are smaller they can affort the better forged pieces and such, so stock for stock they handle it better

Originally posted by got_hp?
rob raymer, running 25lbs of boost all day (http://www.ls1.com/forums/showthread.php?s=&threadid=393293)


whats funny is.........imports + 25lbs boost = 12's, maybe 11's

domestic + 25lbs boost = 9's, maybe 8's.

or faster :D Also, if you were to go back through last year's PHR mags and find the article on a Quad Turbo GM DREC blocked car, can you say, 35#s and 9K+ rpm, making somewhere around 2200 - 2300 HP. Needless to say, its all in the rods, cam, hairdryers, and engine tune.

So they pay for half of what we pay for when we buy 4340 forged engine parts. Its a bit cheaper that way. Also, most of the 4 bangers have DOHC, their 4V heads are extermly efficient and since they are reving a good 2-3000 more than most of us, this gives them even more efficiency.

BUT a 2.0L turbo running 25lbs of boost vs a 7.0L turbo with 25 lbs.....In almost all the cases the 7.0L will make more power and be more reliable. WHY? Since there is a larger displacment it makes the turbo's job to reach your hp goal a little less hard since having that extra displacment helps up the power some more. Also the larger engine wont need to be revved as high to make the power.(notice i said need....casue I know i wanna rev to 8 grand and push 25psi!!:))

I think why most people see imports with lots of boost is becasue they need it to get the power they want.
Since they have less displacment, they will use boost to get to their goal, while people with more displacment will use that to get to their goal and run less boost.

Have you seen the EVO VIII? 19.8 psi on a stock motor! Thats alot of boost to be running through a production car in my mind.
And its only making about 280hp...put 19.8 psi on a 5.7L....you would be silly to not get at least 650 hp out of it.
I question Mitsubishi's reasoning on using such a high boost pressure and coming up with only 280 hp. The STi is using half a liter more and only running 14 psi and its making 300/300 hp/tq. That sold my gf on the STi...now only if I can convince her to let me crush the wastegate in and get a few more psi..:)

Sorry to blab.
Hunter

To try and answer the original question of "why CAN they run high amounts of boost with stock engines":

There are several factors that allow them to run more boost:

1. Smaller bore sizes are far less prone to detonation. For example, my street bike runs 13/1 compression and NEVER detonates, even with 89 octane, 100 degree weather, and 280 degree coolant temperatures.

2. The skirted 6 bolt main engine blocks that many foreign cars use are pretty d@mn stiff and don't break under boost. Chevy, Ford, and Dodge finally caught on to this advantage with their latest families of V-8.

3. The smaller motors can use a reasonably small turbocharger and still make 20 psi boost. My T-trim, spinning at its max rpm, can only supply 14 psi boost to my 355. In order to do 20 psi and up, I'd need a cog-driven YS trim, which isn't all that easy to install or purchase.

Mike

This thread made me finally register.

I owned a 4-cylinder Dodge Avenger for a couple of years until we traded it in for a minivan. The car is mechanically similar to the Mitsubishi Eclipse and Christler Seabring (and maby the Eagle Talon, but that doesn't sound right.)

Anyway, I was interested in getting a turbo charger for it, and I found out that there was a ton of support for it, really because of all of the aftermarket stuff for the Eclipse. Mitsubishi and especially Honda figures out years ago that they could make low-powered cars that passed emmissions and economy laws, but be able to be boosted. Then all the souped-up cars would become free advertising. That's why they have bearing girdles and forged internals on a 2-liter motor that makes 130 hp.

Every new 4-cylinder (and some 6) honda engine is made with minimal external changes (to exaust manifold stud locations, etc.) to make sure the maximum number of existing AFTERMARKET parts will work on it. That way, a new car has after market support before it gets built. Then, people go out and buy new Hondas and soup them up.

Why do you think those companies sponser movies like The Fast and the Furious? Major advertising.

Dodge tried to get on the band wagon with the Neon, but when they went to a bigger 4-banger they made the engines completely incompatable-they rotated in the opposite direction, or something really major like that. No one is going to develope 2 different turbo kits for a Neon when they can develope 1 kit for half of the 4-cylinger Hondas ever made.

Originally posted by Fast Caddie
Kenny duttweiller's TT 4.5L stage 2 Buick V6 just pulled over 1600rwhp and blistered the 1/4 with a 6.90 @200. ~40lbs of boost from intercooled twins. Yes it was on slicks, but tell me something.... where's a drag radial that won't explode from that kind of power? He also built a TT 502 BBC that makes over 2500hp and idles like your average mild-cammed small block. And i can name about 10 turbo6 buicks right off the top of my head that make over 1000rwhp.

See where i'm going with this? It's not an import thing... it's the technology at hand and how you use it. A 350 cubic inch V8 pushed by 25lbs of boost will make a HELL of a lot more power than a 4 banger at a 1/3 of the displacement at the same boost levels. Plus the bigger engine, in most cases, will be able to handle more boost/power before block destruction occurs. Why try to make 2000hp with a block that is known to split at 1000hp? There is a point of sensible practicality.

But back to the import thing, I'm guessing since their parts and such are smaller they can affort the better forged pieces and such, so stock for stock they handle it better

I think you need to read the post I did again. Who said anything about it is an import thing :rolleyes: I simply said Titans supra ran a certian time. Oh! and I know of about 14 or supras over 900pplus hp .... and ??


I have a cutlass with a GM crate motor in it (ZZ430 with a jug) so I am a domestic guy here to (in case there is bashing happening)

Duane

Originally posted by upgradedsupra
Titan motorsports supra runs 8.8@169 on drag radials ;)

Duane

I think you need to read the post I did again. Who said anything about it is an import thing I simply said Titans supra ran a certian time. Oh! and I know of about 14 or supras over 900pplus hp .... and ??

Not bashing... just funny how every post about fast boosted cars ALWAYS ends up with SUPRA in it somewhere. Just out of the blue a supra owner/fan will come on in and "innocently" mention their car. Even on domestic boards. Just making sure you weren't one of the majority of supra owners/fans (with their heads completely up their own ass) that like to poke into everybody's business so they can to brag about their cars and talk trash about everything else. Most must think that the supra is the only fast turbocharged car in the world and that nobody makes a better/faster car. You can't deny that.... look at the net, the movies, and all the ricers in the world. Yes it's a great car.... but lately it's getting rediculous. Some owners are cool though... I know one right here in town with a beautiful Black BPU 6 speed. But he hangs around at the strip and knows what domestics are capable of. There are more 5sec 1/8mi big and small block street cars around here than you can shake a stick at (sadly, most are mustangs and old muscle cars.... few f-bodies to be found).

Just testing the waters bro.... peace

As I said I know what the Domestics are about as I said I have one. (read above post from me)

I do however know what you are talking about. My Supra is actually an MKIII which I don't get to brag. Most people don't even know my gen supra. They think F@F supra :rolleyes:

To be honest even as a Supra owner, the MK4 guys are generally pretty cool but alot are a$$ Plain and simple.

I like both cars (doms and imports)

I actually like my cutlass at the 1/4 mile track better than my supra.;)

Duane

Originally posted by got_hp?
rob raymer, running 25lbs of boost all day (http://www.ls1.com/forums/showthread.php?s=&threadid=393293)


whats funny is.........imports + 25lbs boost = 12's, maybe 11's

domestic + 25lbs boost = 9's, maybe 8's.

hmm you obviously dont know what your talkin about...

most built imports run 11's on sub 20 lbs of boost.. atleast dsms.. it all depends on the turbo choice and its efficiency...

ever heard of john shepard? he ran 8.94 @ 157 mph in his DAILY DRIVEABLE 1991 awd eclipse on around mid 20 psi...

i love imports and domestics but its people like you(in both import and domestic crowds), that are ignorant, that cause all this clashing.. please do your research first..

also, the d16 series of SOHC honda motors can handle up to 15 psi on stock internals with excessive tuning.. and last.. dont have the answer to the question though..

Originally posted by GaRn
i love imports and domestics but its people like you(in both import and domestic crowds), that are ignorant, that cause all this clashing.. please do your research first..


are you retarded?..........read the rest of the thread..........i said it was in jest..........its people like YOU that go off half-cocked and start preaching........wash the sand outta yer crotch and calm down.

Originally posted by teamsleep13

I think why most people see imports with lots of boost is becasue they need it to get the power they want.
Since they have less displacment, they will use boost to get to their goal, while people with more displacment will use that to get to their goal and run less boost.

Have you seen the EVO VIII? 19.8 psi on a stock motor! Thats alot of boost to be running through a production car in my mind.
And its only making about 280hp...put 19.8 psi on a 5.7L....you would be silly to not get at least 650 hp out of it.
I question Mitsubishi's reasoning on using such a high boost pressure and coming up with only 280 hp. The STi is using half a liter more and only running 14 psi and its making 300/300 hp/tq. That sold my gf on the STi...now only if I can convince her to let me crush the wastegate in and get a few more psi..:)

Sorry to blab.
Hunter

19.8 psi on a stock EVO VIII? Who told you that? I think they run around 16#s actually, which isn't that much. 4g63s can easily hold close to 30 psi on stock internals. Anyways, the car is HEAVILY restricted, and maybe even a bit under-rated. All cars in the Japanese Domestic Market are rated at a max of 271 HP, even the EVOs/Skylines/etc, which make well over 300 hp. Open up the EVO's intake and exhaust tracts a little bit, and you're set. :cool:

Originally posted by Fast Caddie
Kenny duttweiller's TT 4.5L stage 2 Buick V6 just pulled over 1600rwhp and blistered the 1/4 with a 6.90 @200. ~40lbs of boost from intercooled twins. Yes it was on slicks, but tell me something.... where's a drag radial that won't explode from that kind of power? He also built a TT 502 BBC that makes over 2500hp and idles like your average mild-cammed small block. And i can name about 10 turbo6 buicks right off the top of my head that make over 1000rwhp.

Hey thanks for mentioning the Buick V6, those are insane numbers for a V6 :alert: .... Of course when you have a guy like Kenny building them, this helps. T/A performance just came out with an aluminum stage 2 block, maybe that's the one he used. The block is only 3 grand. :eek:

Originally posted by got_hp?
are you retarded?..........read the rest of the thread..........i said it was in jest..........its people like YOU that go off half-cocked and start preaching........wash the sand outta yer crotch and calm down.

no, im not retarded... i wasnt going off "half cocked" and i wasnt preaching... i was tellin you what i thought.. im sorry you got upset and decided to call me silly names and make comments about my crouch.. lol i think you need calm down, your making me look better than yourself..

;)

Originally posted by andol469
19.8 psi on a stock EVO VIII? Who told you that? I think they run around 16#s actually, which isn't that much. 4g63s can easily hold close to 30 psi on stock internals. Anyways, the car is HEAVILY restricted, and maybe even a bit under-rated. All cars in the Japanese Domestic Market are rated at a max of 271 HP, even the EVOs/Skylines/etc, which make well over 300 hp. Open up the EVO's intake and exhaust tracts a little bit, and you're set. :cool:

that used to be the the guidlines in japan but its lifted now.. expect to see some pretty fast imports soon.. hopefully the new skyline and supra.. oh yea.. nice car!

to the other guy, it depends on the turbo.. 19 psi on a 14b for example wouldnt yield the same output as say 15 psi from a 20g.. differ CFM's.. so psi isnt the only thing that matters..

To answer the original question...

Cuz a lot of the import motors that are factory turbocharged are between 7:1 and 8:1 compression stock. I think SupraTT's are 8:1 stock.

But keep in mind like, with say a newer motor like the Evo, they are boostin' 17 psi stock (I hear). So they make 17psi to go 13's.

I have heard of boosted up SupraTT's running boost equivalent to the psi that we have in tires (I know a few Sound Performance wrenchers)... Their shop car ran 9..01@153mph at the track recently and it has fittings on the pipes that keep the pipes from separating, like screw type fittings.

You can't compare a boosted cyl' to a boosted V8, Sure some imports go 8's and 9's but they take a different path.

Originally posted by GaRn
no, im not retarded... i wasnt going off "half cocked" and i wasnt preaching... i was tellin you what i thought.. im sorry you got upset and decided to call me silly names and make comments about my crouch.. lol i think you need calm down, your making me look better than yourself..

;)

i didnt call you silly names........i asked a question

if you read the rest of the thread before responding, you would realize someone else already made the same comment you were getting at, and i responded showing that i was making a generalization and have much respect for DSMs, as well as other properly built imports, and therefore your response was unnecessary and redundant.

and the sand in your crotch is a metaphor alluding to your uptight attitude that made you jump on my case before reading the rest of the thread.

Originally posted by zuluman13
Why can imports handle more boost than our cars with the stock bottom end they can handle more and even when both are modified you always see imports running more boost than domestics.
Is ithe bottom end the limiting factor? And, if so, are you comparing in-line engines to v-blocks? What I'm getting at is that I think the real limiting factor when supercharging an american car is the same as an import: detonation.

After detonation is overcome, I think an inline bottom end may have one advantage over v-configured engines, which is that they can be built with a higher bearing-to-cylinder ratio. That's not an import vs. domestic thing, but maby it appears that way because so many people put turbos on 4-cylinder or straight 6 imports.

One thing I think some imports have as an advantage is cylinder head geometry, but that's just an impression I get and not something I can back up. Imports have definetly taken the lead in fuel economy and low emissions. Dodge origionally came out with the Hemi heads in the 30's as an efficiency booster, and later used them because those efficient heads could take higher dynamic CRs without detonation. Maby the same is true with some imports.

Even when modified...
Correct me if I'm wrong, but I don't think many import motors are used for top-fuel dragsters. If you're really talking about who can make the most power, or be built for more boost, there is no comparison to 5000+hp alcohol-blown big blocks. When the "big boys" want to make power, they know where to find it.

Maby the answer to "why they can thak more boost" just comes down to CR, cams, displacement and combustion chamber geometry. The same as all engines. In general, the don't American cars we try to make power with come with bigger displacement, more aggressive timing and CR from the factory, so they can't take as much boost without detonation?

Originally posted by GaRn
hmm you obviously dont know what your talkin about...

most built imports run 11's on sub 20 lbs of boost.. atleast dsms.. it all depends on the turbo choice and its efficiency...

ever heard of john shepard? he ran 8.94 @ 157 mph in his DAILY DRIVEABLE 1991 awd eclipse on around mid 20 psi...

i love imports and domestics but its people like you(in both import and domestic crowds), that are ignorant, that cause all this clashing.. please do your research first..

also, the d16 series of SOHC honda motors can handle up to 15 psi on stock internals with excessive tuning.. and last.. dont have the answer to the question though..

I am not sure but I believe that Shep runs around 30 pounds or so. If you look at his setup he has a 0 to 35 psi gauge and in his in car vid its sweep almost all the way over.


Any one that knows boost know that lower compression and more boost will make more power than higher compression and low boost. I will agree that 4 cyl need a little help here and there to get what we want from them but everybody here knows that there are some quick turbo 4 cyl. They can handle more beacuse we have heads that flow very well stock and our combustion chambers make it harder to detonate.

Just like the Supra thing the top fuel thing is gay. Great Supras can make huge HP numbers, lets let everyone know. OH WAIT everyone does know. Sure I doubt that anyone will get a small displacement motor to make Topfuel HP but that has nothing to do with this discussion. I am pretty sure that no one on this board builds a motor to last for 4-5 seconds. They build drivers.

Mitsubishi and especially Honda figures out years ago that they could make low-powered cars that passed emmissions and economy laws, but be able to be boosted. Then all the souped-up cars would become free advertising. That's why they have bearing girdles and forged internals on a 2-liter motor that makes 130 hp.

Every new 4-cylinder (and some 6) honda engine is made with minimal external changes (to exaust manifold stud locations, etc.) to make sure the maximum number of existing AFTERMARKET parts will work on it. That way, a new car has after market support before it gets built. Then, people go out and buy new Hondas and soup them up.

Why do you think those companies sponser movies like The Fast and the Furious? Major advertising.

Dodge tried to get on the band wagon with the Neon, but when they went to a bigger 4-banger they made the engines completely incompatable-they rotated in the opposite direction, or something really major like that. No one is going to develope 2 different turbo kits for a Neon when they can develope 1 kit for half of the 4-cylinger Hondas ever made.




You gotta be freekin crazy. Honda makes civics as an inexpenicive economy car. the percentage of people buying them to hook them up is small compared to who actualy buys them for their intended use. Honda makes the internals strong because thats what makes a good, dependable engine no other reasons. Your crazy. and yes dodge did jump on the band wagon of turbo'd sport compacts.......the 19k SRT-4 is quite impressivewith stock 14.2's, thats enough to have plenty of aftermarket tuned civics to **** their pants.

bottom line- its crazy to think honday makes civics for turbocharged reasons

oops that top section should be quoted! haha not my work!
:alert: :alert:

I'm not attempting to add fuel to this fire! I know this guy with a newer Civic. He has all the body kits and lowered etc. He was running at 5-6lbs of boost and I believe it might have been a stock block (not sure) and I had a stock Z28 at the time and everytime we raced I walked away but he did do a good job of keeping up (before mods) on 91 octane. So I guess it takes about 6lbs of boost to get close to a N/A Z28.

Chevy is also getting into this and they have an "Eco Tec" Turbo Cavalier that they are putting through the ringer. www.year2032.com/ecotec.pdf just seems like the 4-6 cyl are using turbos to make up for the lack of displacement and there's nothing wrong with wanting to go faster....just wish they would sound better:)

Tony D., I totally agree. About 99.5% of Hondas end up in the hands of married women, who barely even know the import drag scene exists. You think Honda puts forged pistons in 100% of their cars so .02% of the people can put turbochargers on? You've lost it. The engineers design those engines for reliability, low cost, low emissions, smooth idle, quiet operation, low oil consumption, and high fuel efficiency. NOT forced induction capability!

If the engines stay externally the same over the years, it's probably because the assembly line is easier and cheaper to re-tool with the new models. If they have forged pistons, it's because they wear slower than cast. Etc. . .

Mike

Originally posted by Slow95car
boost != airflow.

who cares if they are running 25psi, they still aint movin as much air as you at say 12 psi.

That's absolutely correct. It really boils down to how much air you can cram in there. We don't get turbo/super chargers for the psi numbers, in the end it's a high CFM that we want.

air CFM + fuel = power

And that is the point a lot of people are making. Generally speaking, a 4-banger with high boost will flow close to a V8 with low boost.

There are many other factors involved, but quite simply an engine is an air pump. The more air it can pump, the better it performs.

The simple fact is that imports (with exception to the Supra and a very few others) can hardly make over 400-500 hp without tons of money. A shop in Greely Colorado got a CRX into the 9's but it took $200,000 with all of the broken motors, trannys, and perfomace parts. I can only dream of what my car would be with that (In the 9's with a new Ford GT in the driveway :D) Plus most imports that people talk about are transaxles and lets face they are not as strong as a regular tranny. What would the power be worth without being able to put it to the ground. Then, yes the Supra can hit 9's on the stock block (so can the 03 Cobra, but it was on the stock rear, tranny, bottom end, and it was only at 18 lbs of boost), but truthfully how much faster can it really go on better internals maybe high 8's. If you are looking for the most straight line power you can have, build a high displacement motor for boost and have 2000+ hp.

I thought the imports ran higher boost because their engines were smalle? put a turbo on a 4banger, and it makes 15 psi boost, put it on a v8 and it makes ~half the boost. Both would make the same HP, everything else equal. Atleast, that's how I always thought of it.

i387 is correct, everything depends upon how much air/fuel you can shove into an engine.

Originally posted by CamaroFreak87
I thought the imports ran higher boost because their engines were smalle? put a turbo on a 4banger, and it makes 15 psi boost, put it on a v8 and it makes ~half the boost. Both would make the same HP, everything else equal. Atleast, that's how I always thought of it.


thats why they NEED to run higher boost


i think what he was asking is why the stock motors can HANDLE more boost............and thats typically because the ones that handle high boost came from the factory with forged internals and low compression.