[lester]

i'm trying to get ppl's opinion on this matter here.

so i feel a motor build is in order. i've been doin research and here is what i have found so far:

among motor builders is AR Fabrication, Axis, Cosworth, Cobb, and Crawford. There are probably a few more out there but these are the ones i know about.

In order to see the fruition of a motor project i have to figure out how i want the engine to perform and what power level i want it to be at.

I want an engine that has minimal lag but has high revving capabilities and hit around 450whp on pump all the while maintaining good reliability. This car will be daily driven. I'm thinking that is asking for alot but i have been researching and asking questions. I will eventually find an ideal setup for what i'm going for.


What I still have questions on.

sleeves - are they really necessary on street driven vehicles? how much psi does a block need to be running before a sleeve upgrade is needed? and do they really sink into the block? Dalton and jeremy@cobb don't think so according to this thread:

Anyone heard of Cosworth sleeves droping?


choice of turbo? (that have good spool and good power capabilities) I'm thinking a rotated GT35R twinscroll. at what psi would that turbo create 450whp. maybe GT40?

bigger displacement or higher compression?(to combat lag) from what i understand so far by what motor builders are telling me is that larger displacement motors do not have the capablility to rev high. they also inform me that the higher revs is where the larger framed turbos(like the GT35R and up) make more power because the turbo is able to flow more air at elevated rpms. i hear that engines of the stock displacement and lower, along with worked heads will be able to achieve high rev capabilities. but my general understanding is that a lower displacement will spool a turbo slower. however, i recently was introduced to the idea of a higher compression engine like 9.2:1. to combat lag. this lower displacement along w/worked heads would allow for the utilization of a higher than stock redline which = more airflow = more hp.

if the motor was at higher compression, could it be safely tuned on pump gas? one motor builder said he would not recommend anything higher than 8.5:1 unless it was running strictly race gas. However, i was informed by one fellow that it is difficult to tune it but possible.

semi-closed or fully-closed deck? is the fully closed deck more durable? i see that the 2.2l block is fully-closed (is it also iron?). could you stuff built 2.5l internals inside a 2.2l block to increase the displacement to 2.5l?

can a bigger displacement motor hit 450whp-500whp on pump gas reliably w/less lag than a 2.5l? somebody told me that the bigger motors don't spool up turbos much faster.

what about the crank? should it be upgraded or reworked for better oil flow? i hear that at higher rpms, the oil in the crankcase will be affected by the centrifugal force caused by the crank thereby starving the bearings of oil which can lead to spun bearings. how valid is taht statement?

anybody know about copper o-ring decks? ar fabrication mentions that.

these are all the questions i could think of now. please let me know what you guys think on the subject.

thanks!

[twigg107]

Well just remember that the higher hp/tq, reliability goes out the window. Your best bet is to call up some of those shops and talk to them. They can guild you too your goals.

Personally Iam going with a sleeve'ed big bore custom closed deck block that I will be building myself with AWIC and gt30r. But for DD Iam shooting for 380hp give or take.

[Flycaster]

Talk with Jeremy, Ron, Quirt, Howard and Cosworth. Then talk to a few tuners. Then, after you're thoroughly confused, come back here, search, and read a bunch of posts. No offense, but after that, you'll have better and more specific questions.

[CrawfordPerformance.com]

You might as well take our name off your list as we cannot supply you with a motor package that will meet your goals and make 450 to 500 HP at the wheels on pump gas.

Our 2.9L monster motor can meet all your goals, except the HP

Good luck with your project.

[mxpop]

Crawford,

What warranty do you provide with your complete motors?

[CrawfordPerformance.com]

We warranty the labor involved in building our motors, if we make a mistake during assembly, we take care of it at no charge to our customer.

We also brutalize all our motor packages in our Time Attack car to make sure that you will not have a component failure that would be caused by anything other than some form of neglect, which is usually tuning related.

We also shoulder the cost of R/D and do not offer a product until it has passed through extensive testing. Beware of companies that use you as an “investor” in their R/D projects, it can be expensive and time consuming!

Thanks for asking mxpop

[Jeremy@Cobb]

http://www.harmanmotive.com/Gallery/STI/Chase/dyno.jpg
485WHP on 91CA pump nothing else added. (this is daily driven) 20k+ on it now.
Obviously if you are going after pump gas numbers and arent looking for higher power levels with race gas you would not need such a large turbo (this car uses a GT35R w 1.06 housing).
Full specs on car- http://www.harmanmotive.com/Gallery/...ase/index.html

- J.

[lester]

yeah i know chase. i talk to him at meets. he just recently sent his longblock to you because of a blown head gasket i believe. did you guys get a chance to look at his block yet?

[lester]

Originally Posted by Crawford/I-Speed

You might as well take our name off your list as we cannot supply you with a motor package that will meet your goals and make 450 to 500 HP at the wheels on pump gas.

Our 2.9L monster motor can meet all your goals, except the HP

Good luck with your project.

thanks

somebody told me you guys are almost about done with the R&D process with the 2.9l. and you guys have been researchin it for the last few yrs. hope you guys finish it soon enough

what are the prices of the blocks on your site? i don't see any posted costs.

the R3 block you're carrying, is it a bigger bore? i noticed the 79mm crankshaft.

how high does your S5 block rev with the 84mm stroke?

[B4RSTiwsnc]

I had the Perrin GT35R kit on my 05 boosting 25psi with meth injection, stock internals, for about 10k and it was my daily driver, I dynoed 454awhp and the car drove great....

[modaddict]

lester,
higher compression engines are HARD to tune without detonating itself to death. it's possible, just hard.
450whp on pump is HARD to achieve. You need a bigger desplacement engine to get that reliably, IMO...you're then talking a stroker engine. If you use water/meth, torco, or race fuel....this isn't a problem on a gt35r kit.

Sleeves will be beaten to death untill subaru's are long gone. builder 1. will say yes, builder 2. will say no. builder 1 says an rpm limit, builder 2. says a boost psi limit. Most shops can build a good engine that will last you a LONG time.

The biggest key to a long life engine is ZERO detonation. A HUGE key to oiling the crank is no detonation.

[crystal_Imprezav]

1) Skip the time looking over stroked motors. No point, none at all. Through everything I have seen, it will not make more power or spool faster. It will only run rougher, way rougher, and be more likely to break being that our motors really are not made for it. I PERSONALLY would NOT trust ANY builder unless I was there to watch ALL the R&D on a stroker and ran all the calcs to double check. This isn't to mention I seriously doubt any commercial tuner in the country has the brains to tune it (maybe 2-3 I would recommend). Like I told you when we spoke... If its your DD please move on from the stroker idea.

2) If its your DD, don't sleeve it. IMO sleeves are not made to be run on a DD car. Chances are, if your not running 500awhp on a DD (or running n2o), you dont need it. I think many builders will agree here with me.

3) If your looking for big power on a DD with no lag, your only option pretty much is to go with a high compression motor. However please be aware of the draw backs. Be aware that it will take WAY more than 6 hours to tune the car. While most tuners are only going to mess with the WOT tune, I can GUARANTEE you the DD and part throttle tune is just as important. The stock part throttle timing WILL BLOW THE MOTOR UP. Cams & a valvetrain/porting are a must. They complement the HC which is well worth the costs. Again, I can't stress enough how important the tune is. Be prepared to pay the costs to tune it. Also be aware that one bad tank of gas and you can say bye-bye to a head gasket or some spun rod bearings.

4) Please also DO A LOT of RESEARCH on high compression motors. There is way more involved than just the longblock. For example: plugs, ignition, quench, clearances, just to name a few. Also consider that FMIC piping has a lot to do with that extra bit of lag that blows. Also consider the fact that HC motor run way hotter than a lower compression motor. The tune, parts, cylinder pressures, intake manifold, fuel rails, headers, and etc. are all going to play a HUGE part in the success of the setup. Just throwing a stock setup into that longblock will guarantee 1700* egt easy with a decent tune and above 1k* just cruising.

Just to name a few thoughts. I could keep going on and on and on. Flycaster, Jeremy, and Bruce's turn!

[crystal_Imprezav]

Some high compression tunes that took a lot of work.




Also be aware that on PUMP GAS, a lower compression motor will pretty much outshine a HC motor any day of the week unless its about to blow up. On higher octane, the HC will start to show its strengths. Also look at where it hits 300hp/tq compared to a LC motor and also the more proportional torque to power ratio.

[Flycaster]

I have 2 questions. Did you break the motor? Have you driven a car with "only" 400whp?

If the answer to these is "No", I really think we can save you a LOT of money because you can do that with a bone stock block, no problemo. But 500whp, on a tough dyno, on pump? Ain't gonna happen. The block isn't the problem, it's displacement, and a measly few extra cu.in. isn't enough.

[mxpop]

Originally Posted by lester

I want an engine that has minimal lag but has high revving capabilities and hit around 450whp on pump all the while maintaining good reliability. This car will be daily driven.

Back to this part of the OP, why is it so important to use pump gas after you are so willing to do the work/expense of building a motor with virtually every aspect modified or changed?

Race gas is really easy to come by and a 450whp STI is not a likely long distance commuter or cross country car so you wont likely be filling up anywhere far away on a regular basis. If you do need gas far from home, you can simply click over to a milder map that will accomodate your drive home. A tank of gas should last a minimum of 200 miles for a DD street car and then you can refill with race gas at home.

I just dont understand why people are so willing to double the cost of their car with mods but arent willing to increase their fuel budget and effort.

I know for a fact that VP fuels will sell race gas in 55 gallon cans that you can have at home in your garage. 109 unleaded is about $7 a gallon including the drum itself and will give you a lot of power and great tuning potential. They have great leaded gas too if you go that route. If they wont deliver to your residence, then you can have an auto shop or motorcycle shop get it for you and even supply a pump.

"I want an engine that has minimal lag but has high revving capabilities and hit around 450whp on pump all the while maintaining good reliability. This car will be daily driven" Over 200chp per liter with low end torque, quik response, and high revs is a lot to ask for out of a 2.5 liter 4-cylinder motor, esp when you limit your fuel diet.