kevinoneill

I wanted to hear from some of the "big" guys on this.

Would you say one would be more reliable than the other? or more potential? etc...
Please assume compression and boost to be the only variables.

boosted92

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by issues4 &raquo;</TD></TR><TR><TD CLASS="quote">I wanted to hear from some of the "big" guys on this.

Would you say one would be more reliable than the other? or more potential? etc...
Please assume compression and boost to be the only variables.</TD></TR></TABLE>

This is about as close of a comparison as I can get. I have a friend with a hatch, sleeved GSR, 84MM 10:1 JE pistons, stock head, same valve springs/retainers as me, same ITR cams, same victor X intake manifold, same inline pro manifold, same AEM EMS, i'm running an SC61, he's running a T3/60-1, both running ITR trannys. He runs 13 pounds of boost on pump gas, I run 19 pounds of boost on pump gas, my car walks away from his like it isn't even funny, he has a slight advantage off the start because he has more displacement and starts boosting slightly quicker. 9:1 compression is, IMO, perfect for a street car.

kevinoneill

Thats a good comparison. He gets of the line faster due to earlier spool (larger dispalcement with the 84mm). Why is you think you walk him further down the road?

Maybe the higher compression/lower boost doesn't let your friend's turbo boost high enough to be in its optimum range?

jeremy.

i would have thought the guy with the higher compression would have put up more of a fight....

boosted_dc2

there are allot of posts in the archives about this. my opinion is that somewhere in the middle is good, like 9-9.5:1. ive seen some people run 8:1 and run like 25 psi. some people run like 10:1 and run like 10-15psi. i think it all depends on tuning and preference. one question i hate is "how much boost you running?" do you want to be the guy that says " i run 30 psi" or the guy that says 10. personally im going to run about a 9.3:1 and run 15 psi with an sc-61. also how much boost you run has to do with turbo selection, are we talking 20 psi on a t-25 or an sc61. big difference, kinda went of on a tangent but theres allot of thought to both applications.

Landon

kevinoneill

Completely understand and appreciate your view point. I'm hoping to find some Pro draggers out there that have maybe tested both ways and chose one or the to other and why they chose it.

uncleben'sspanishrice

I was at NED the other night with sleepyEG and kp4321 and saw something interesting. This guy had this huge beutiful front mount on his new RSX, so I went up to see what turbo setup he was running. Funny thing was he wasnt running any trubo. Interestingly, the air filter was attached directly to the intercooelr inlet pipe and the intake tube was directly piped into the intercoolers outlet. He claims he was making a good deal more power with this setup. We all thought it was kind of odd though. But, when he started it up, damn it was so loud. The intake noise was crazy. It even had lag like a normal turbo car when he revved it up. Sure proved to us that it was making a good deal more power with his intercooler. Just wanted your opinions. I am considering doing this to my b18c5 in my GSR as I really dont have the room for the turbo, just the front mount. Any thoughts?

dasher

hahaha ... that is a funny story ...
I hope my assumption is correct that you are joking ..

Rick Solis

Just run the piping into the headlight duct with a mesh screen over it. That would be way less restrictive than an IC.

ExVtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by uncleben'sspanishrice &raquo;</TD></TR><TR><TD CLASS="quote">I was at NED the other night with sleepyEG and kp4321 and saw something interesting. This guy had this huge beutiful front mount on his new RSX, so I went up to see what turbo setup he was running. Funny thing was he wasnt running any trubo. Interestingly, the air filter was attached directly to the intercooelr inlet pipe and the intake tube was directly piped into the intercoolers outlet. He claims he was making a good deal more power with this setup. We all thought it was kind of odd though. But, when he started it up, damn it was so loud. The intake noise was crazy. It even had lag like a normal turbo car when he revved it up. Sure proved to us that it was making a good deal more power with his intercooler. Just wanted your opinions. I am considering doing this to my b18c5 in my GSR as I really dont have the room for the turbo, just the front mount. Any thoughts?</TD></TR></TABLE>

Thats gh3y. I would like to see #'s on a Dyno. How would you know @ idle it was making more power.

kevinoneill

Although cool...that was Waayyyyyyy of topic. You should of made your own post.


Modified by issues4 at 5:08 PM 4/12/2004

uncleben'sspanishrice

sorry about that, ill make my own post, I meant to, woops

psileepR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by issues4 &raquo;</TD></TR><TR><TD CLASS="quote">I wanted to hear from some of the "big" guys on this.

Would you say one would be more reliable than the other? or more potential? etc...
Please assume compression and boost to be the only variables.</TD></TR></TABLE>

BACK to the topic.
I cant afford running race gas all the time so my vote is for low compression high boost.

The tuning window on a high compression boosted motor is pretty small. Im pretty sure driving around town will be great due to the quicker spool and better low end response, but thats something that i can live with.

M.A.R.C.

imo as boosted_dc2 stated somewhere between 9 and 9.5:1 should be a good compromise

danl

Boost makes power, do what you can to run as much of it as you can.

Don't listen to the pro import racers. No offense, but they aren't dummies. If your lucky they will just stay hush hush. If they are smart, they will purposefully decieve you. When racing is your living its all for blood baby.

Lets put it this way, I'm a fairly competitive fella. In highschool I accidently messed up my buddies knee in a wrestling match. Thats what a fairly competitive person does when competing against a friend. How do you think someone is going to treat a stranger?

Rick Solis

regardless what any of the pro guys will tell you, their motors run right on the edge. Some of which are running 11.0+ compression. But of course like anyone whos livings are made by staying on top, they are going to tell you the complete oposite of what theyve found to work the best to keep the crowd at arms length in comparison to their advancements. Bottom line, higher compression will make more power per pound of boost than lower compression.

Forged internals, sleeves, good tuning and race gas for both motors, The motors being identical B18C builds with only one difference. One is running 10.0:1, the other running 9.0:1, both running 20 PSI.. Now you tell me whos going to make more power?

Its all in how you want to make power. Im a firm believer in making power with the motor and using the turbo as an ade in producing power as apposed to making power with the turbo. To me, making 400+WHP with 15 PSI or below is more of an accomplishment than making the same 400+ at 20+ PSI.

It all really comes down to personal preference though ::shrugs::

turbo96wr

i will tell you what i ran and am going to run this year, last year 10:1 comp.. 35lbs on methanol, this year i am going to run first motor 8:5:1 40-45lbs of boost second motor has 8:0:1 45-50lbs more volume in cylinder all on methanol.
JE PISTONS,AEBS BLOCK,PAUTER RODS ALL FERREA VALVE TRAIN WITH SPECIALLY MADE SPRINGS 1_ _LBS SPRINGS, TURBO GT42R, MOTEC, MOTEC CDI DONE BY TONY1 and BOB NORWOOD see you at the races.

kevinoneill

wow...thats alot of boost. Looks like you took the low compression high boost end. Would you ever think of going high compression and dropping the boost level?

Thanks for chiming in. cheers.

hotasscivic

imo i think 9.5.1 is ideal because its not too low so you have power without the turbo but not too high where you have to always worry about detonation everyday. i have a friend who runs 10.1 in a gsr with a 60-1 and has almost 30,000 miles on it with no problems what so ever so far but its tuned VERY WELL. so i think its all a matter of opinion and how well you can get it tuned. just my two cents .

vtec.dc2

for every hp goal theres a reasonable compressoin to run.. so more hp, less compression.

turbo96wr

no, more boost makes more power and better windows for tuning remember i have a great tuner working with me bob norwood.

boosted_dc2

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbo96wr &raquo;</TD></TR><TR><TD CLASS="quote">no, more boost makes more power and better windows for tuning remember i have a great tuner working with me bob norwood.</TD></TR></TABLE>

better window for tuning???huh......explain what you mean please.

Landon

tony1

There are alot of variables in choosing a setup. For street and high horsepower, I'd definitely recommend 9:1. You can make a little over 400whp with 9:1 on pump gas and it be very reliable, where that's pushing it with 10:1. Where you are not limited to the amount of boost you're gonna run, you can run low compression and high boost. The powerband of a drag car is very narrow and driveability off boost is not important, so low compression high boost is the way to go. If you are limited to 30psi and are running race gas, then 10:1 is the way you want to go. Since going 9:1 will make less power at 30psi than 10:1, there's no point if you can't make up the difference with boost. Ultimately you can make more power with low compression and high boost, it just takes more boost to do so...

JDogg

the lower compression you go the more power you can get out of said gas. even with race gas there is a limit to the power you can make. the lower your power goals the higher the compression you can run. there are points of deminishing returns though. going from 8:1 to 7:1 isnt really gona gain you anything.. no street car is gona make enough power to need compression that low. for an all out street car 8-8.5:1 is what i like. that way you can make 500ish on pump gas. for a mild street car built to make 300-350hp, 9.5 or 10:1 is good. anymore power and you will need race gas.

RyanEJ8

JDogg and Tony1 made very good points.

I went with 10:1 since my goal is 300-350whp. With the lower hp goal why not take the faster spool up and better low end that comes with higher compression? It'll be more fun on the streets.