damn, i got my car dyno'd today at elite autosports in minneapolis(isaac as tuner), and was hoping for around 250-280whp and to my disbelief, i was at 175whp on my first run!! **** i said, i was so embarrassed and not to mention, disappointed!! next run was 180, followed by 203, 205, 208 and 210. and this was all at 10psi!! so over all i was at 210.6whp and 193.2wtq. i was thinking...there's got to be something wrong. isaac suggested that the timing could be too conservitive at -1degree per lb of boost using UberTeg's chip. and it could of also been because i have only 155+/- 5 compression in each cylinder...probably due to low compression pistons??? my question now is, is there anyone in here using Ross pistons for boosting and if you are what kinda of compression do you have in your cylinders? and what numbers are you posting on the dyno's???

sorry guys but here's the pictures...the manifold is MPRacing from vegas and all that black crust is engine paint that we tried using that just baked off. and i guess my pistons aren't 9.5:1, but 9.1:1 or lower.
edit: damn the pictures aren't working so here's the link: http://www.ofoto.com/BrowsePho...age=1




Modified by shermanyang at 2:44 AM 6/9/2003

 

can you tell us your entire set up so we can further evaluate everything? headwork, blockwork, compression ratio, turbo sizing/ar trim, fuel upgrades, etc etc.

 

wasup sherman.. nice talking 2 u 2night... i forgot to mention something about your numbers..

you gotta remember, that's 210 Wheel HP... So inessence, you're probably getting about 250 or so at the crank.. in stock trim, i believe the LS puts out about 110 or so at the wheel... so w/ about 10 psi of boost, that comes out to about 10 hp/psi, which is the avg i believe...

good luck at the track.. because its the numbers at the track that really count..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GudeH23a &raquo;</TD></TR><TR><TD CLASS="quote">can you tell us your entire set up so we can further evaluate everything? headwork, blockwork, compression ratio, turbo sizing/ar trim, fuel upgrades, etc etc.</TD></TR></TABLE>


okay here's my complete setup:
motor: Ross pistons 9.5:1 .02 over, eagle rods, arp bolts, str blockgaurd, home port & polish of the intake and exhaust ports.

turbo: t3/t04e .63/.60 .57 trim, MP racing equal length manifold, deltagate wg, type-s bov, 2" intercooler piping, huge single core intercooler, race cat, 2.5 dp & exhaust.

ems: UberTeg's chip -1degree per lb of boost, 3.5k 2 stage launch, dsm 450 injectors, S-AFC.

i think that's about it for now...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92HB_HB &raquo;</TD></TR><TR><TD CLASS="quote">wasup sherman.. nice talking 2 u 2night... i forgot to mention something about your numbers..

you gotta remember, that's 210 Wheel HP... So inessence, you're probably getting about 250 or so at the crank.. in stock trim, i believe the LS puts out about 110 or so at the wheel... so w/ about 10 psi of boost, that comes out to about 10 hp/psi, which is the avg i believe...

yeah it was nice finally getting a chance to talk to you as well. yeah i know what'ca mean...so i've finally decided to take my car to the tracks this sunday. i'm just dissappointed because people were making more power than i am on a stock ls with only 7-8 psi!! it's just the thought that i'm making so little power at such a high boost level(it's high for me since i'm not using a 3bar map). i know i'm fast cause i've beaten my buddy's gs-t boosting 16psi, and my other buddy's mr2 turbo boosting 10psi. also i'm able to keep up with my buddy's 2000 vette at 155mph. so i'm wondering why i'm dyno'n so low. gosh, this is gonna puzzle me too much. damn it's time to slap the v-tec head on now to raise the compression!!

good luck at the track.. because its the numbers at the track that really count..</TD></TR></TABLE>

 

i have ross pistons but, i don't think your low numbers are due to the pistons. my compression numbers came back around 185-190 for all four cylinders.

 

I really don't think it's your pistons. 9.5:1, I think, is great for a turbo car. You are only boosting 10 psi, and to expect 280whp is a little over board. It's not like you got a T3 60-1 . Besides Ross makes a good piston! Your numbers are good for the management you have.
Good kuck!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hatch4urSnatch &raquo;</TD></TR><TR><TD CLASS="quote">i have ross pistons but, i don't think your low numbers are due to the pistons. my compression numbers came back around 185-190 for all four cylinders.




I really don't think it's your pistons. 9.5:1, I think, is great for a turbo car. You are only boosting 10 psi, and to expect 280whp is a little over board. It's not like you got a T3 60-1 . Besides Ross makes a good piston! Your numbers are good for the management you have.
Good kuck!
</TD></TR></TABLE>


see, i was hoping for the same compression #s you're getting but for one reason or another they're 155 across. and yes i think it could be because of my ems that i'm using but people have made more than i have just using the hack which is i think a step below Uberteg"s chip.

 

What motor is this?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbo Si &raquo;</TD></TR><TR><TD CLASS="quote">IYou are only boosting 10 psi, and to expect 280whp is a little over board. </TD></TR></TABLE>

i don't think that is overboard because i made 291.3 hp in between 10-11 psi.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hatch4urSnatch &raquo;</TD></TR><TR><TD CLASS="quote">i have ross pistons but, i don't think your low numbers are due to the pistons. my compression numbers came back around 185-190 for all four cylinders. </TD></TR></TABLE>
What's your piston compression?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hatch4urSnatch &raquo;</TD></TR><TR><TD CLASS="quote">

i don't think that is overboard because i made 291.3 hp in between 10-11 psi. </TD></TR></TABLE>
What size turbo?

 

The compression #s seem alittle low for having 9.5:1 CR, my 9.6:1 were 175psi across the board, do you know any specifics on your pistons? Dome ccs, compression height etc? Is it the Pistons listed on their site? They have 2 different shelf pistons listed one is part # 99808 and is 8.5:1 and #99807 which is 9.2:1

 

they are supposedly 9.0:1 compression. never got a straight answer from the person who built the engine. i'm also not sure if the larger bore raised the compression either.

 

don't know. XS engineering "T3/T4" turbo.

 

even Isaac my tuner said that those were really low numbers for the amount of boost i was pushing. he said i should of been at least in the 250whp range. and my torque curve looked kinda sad too IMO. i'll be posting up my dyno sheet as soon as i can find someone with a scanner.

 

We'll I still don't think it's the pistons. I run Weisco 8.8:1 and was getting 50 across the board. Have you spoken to the person who built your bottom end? Are you noticing any smoke coming out of your exhaust or breather filter? Are you losing any oil?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Boostfed &raquo;</TD></TR><TR><TD CLASS="quote">The compression #s seem alittle low for having 9.5:1 CR, my 9.6:1 were 175psi across the board, do you know any specifics on your pistons? Dome ccs, compression height etc? Is it the Pistons listed on their site? They have 2 different shelf pistons listed one is part # 99808 and is 8.5:1 and #99807 which is 9.2:1

</TD></TR></TABLE>


HOLY ****!! Hey thanks Boostfed!! All this time i though they were 9.5:1!! Ross themselves told me this when i called them. so they're 9.2:1 huh?!?!! well if you need the specs here they are:

.306 deck thickness major front
.292 deck thickness major rear
.15 minimum thickness under intake valve pocket
.176 minimum thickness under exhaust valve pocket
.22 minimum thickness at top of dome
.136 intake valve pocket to top of ring groove
.155 exhaust valve pocket to top ring groove
.144 side relief
.056 pin hole to side of pin boss
.7 pin engagement in pin bosses(each side)

well, these came off the sheet that were with the pistons. hope this helps.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbo Si &raquo;</TD></TR><TR><TD CLASS="quote">We'll I still don't think it's the pistons. I run Weisco 8.8:1 and was getting 50 across the board. Have you spoken to the person who built your bottom end? Are you noticing any smoke coming out of your exhaust or breather filter? Are you losing any oil?</TD></TR></TABLE>

well...umm...i kinda built my bottom end lol, and no i don't get any smoke at all only every now and then after extreme boost but i figure that's normal. and it's not black smoke...white smoke only. the shop only bored my cylinders and welded my block gaurd in.

 

1 degree of retard per psi is a little too conservative. I'd start at around .75 per psi, and tune from there if possible.

Ryan P.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SJP0tato &raquo;</TD></TR><TR><TD CLASS="quote">1 degree of retard per psi is a little too conservative. I'd start at around .75 per psi, and tune from there if possible.

Ryan P.</TD></TR></TABLE>


that's the problem...i can't do anything about it because i don't have the program/burner and UberTeg isn't around anymore so i'm stuck with those specs. I'm gonna try and sell or trade my S-AFC, P74 with UberTeg's chip w/3.5k launch for a hondata or something.

 

well, even with my factory pistons with teh compression of 9.2:1, the compression numbers came back as 175-180.

 

I plugged in the Piston Dome Displacement of -6.1cc per Ross' site for those pistons, used the c-speedraing Compression Ratio calculator and it came up with 8.86:1 CR for a B18A/B block .5mm overbored, stock head and stock gasket. So Ross' CR info may be wron on the site, if you look anyways at their CR, they are not consistent on the site showing diff for B16A,B18B, B18C head ccs. Check it out
" STOCK BORE SIZE IS 81 MM (3.188)

BORE
STROKE
DISH CC
WEIGHT
C.H.
PART #

3.209
3.504
-11.9
310
1.180
99808

3.209
3.504
-6.1
289
1.180
99807


COMPRESSION RATIO WITH HEAD CC OF:

PART #
41.6
42.7
43.8

99808
8.6
8.4
8.5

99807
9.4
9.4
9.2"
Also plugging in stock bore it is 8.7:1

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hatch4urSnatch &raquo;</TD></TR><TR><TD CLASS="quote">well, even with my factory pistons with teh compression of 9.2:1, the compression numbers came back as 175-180. </TD></TR></TABLE>


exactly what i was saying to my mechanic and to ross. but they said just slap the turbo on if i'm not burning oil which i'm not and if the compression were the same all the way across.

 

another thing.. it may be your exhaust system as well... if possible, you should try and upgrade to 3" setup, mandrel bent of course... Again, like my traction bar setup, I fabricated my own 3" exhaust system as well.. I can give you a shopping list of parts needed to fab your own system if you like..

my DP starts out at 2.5 and merges to 3" under the oil pan.. from there, its 3" all the way out to the rear bumper.. I believe my cost of materials for the setup was approx $80 give or take $20... I also noticed that when I took off my axle back section of my exhaust system, it freed up the flow and spool up time was alot more responsive... so thus, your 2.5" system is probably the bottle neck at this moment..

as for getting hondata.. if you're on a budget, I was just reading the FI forum and Kyle, just posted a topic regarding the UBerteg chip and a possible hondata deal w/ the older and used 2b systems.. not too sure about the specifics of the deal yet, but it might be of great interest and the perfect opportunity for you, so watch that thread like a hawk...

I just bought 2 s200b systems from him today since he had a killer price and I could not let the opportunity slip me by..