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twistedbird
05-20-2012, 07:41 PM
i have a 91 sc with some new internals raised compression 8.8 to 1, 94 ported blower 15 % overdrive, mp plenum,db intercooler,some 60 pounders, 76 cnl, chip by dd, 2 1/2 dual in dual out exhuast, and its only cranking 255 rwhp. boost is at 14.8 psi
M I missing something or does that sound right. If anyone can shine some light thank u

XxSlowpokexX
05-20-2012, 07:48 PM
no cam or head
work?

I wouldnt expect much more

twistedbird
05-20-2012, 07:57 PM
yes 212/224 i think 500/500 lift, ported heads.

XxSlowpokexX
05-20-2012, 08:04 PM
I have seen sim setups with a bit more cam making closer to 300. Being Dave burnt the chip maybe he can shed some light. Could be running low timing which would makes a diference power wise

twistedbird
05-20-2012, 08:14 PM
yeah we haved he made some changes to it the 3rd time adding timing to it, i was just hoping someone else might know something were over looking, nd the cam is from dd to.

JasonMiller94SC
05-20-2012, 08:37 PM
That's not bad power. Is your Throttle body large enough to support the MP inlet and 15% od?

I have about the same mods on my car with some 1.8 roller rockers and an 85mm throttle body and an 80mm maf but I'm only runing my blower at 10% over. Maybe the air is heating up too much from the OD and pulling timming out? Maybe the belt is slipping? With 10% OD the dyno boost gauge said 16psi with my car.

twistedbird
05-20-2012, 08:44 PM
it has a 75 mm bbk, i was hoping for 300+ rwhp

XR7 Dave
05-20-2012, 08:53 PM
There are just a lot of variables that would have to be eliminated before I would pass judgement. For example, when we built Pablo94's car the best it would dyno was about 260rwhp but it ran 12.70's at the 2009 SC Shootout. While 260rwhp was the best it pulled with a cool blower and IC, on most dyno runs it was more like 250rwhp.

With an automatic and a double intercooler I very often have a hard time getting any kind of a decent dyno # because the IC heat soaks and it won't cool off.

I think you also have a non-locking torque converter so that pulls the #'s down some too. What gears do you have?

twistedbird
05-20-2012, 09:35 PM
3.73 gears

JasonMiller94SC
05-20-2012, 09:54 PM
Well here is my recepie and it was only good for 291 RWHP but I'm happy with how it runs.


K&N 9" cone filter
80mm LMAF
3.5" chrome intake tube
85mm Magnum Powers Throttle Body
Magnum Powers inlet
Magnaport II blower
3/4" raised SC top
Double IC with fan
180 degree T-stat
10% overdrive supercharger pully
ASP underdrive pulles
BHJ ballencer
Custom exhaust 2.25" pipe with Hi-flo cats to Terminator Resonator into 3" pipe split into 2.5" pipe w/ Bullet Stainless Steel Mufflers and ported manifolds
Dyno Tuned and Computer programed by Jerry
255lph high pressure in tank fuel pump
Ported heads and intake
Morana Racing 1.8 Roller Rockers
60lb fuel injectors
custom cam
forged pistons & rods

and if you add the Zex dry kit it pulled 370 rwhp.

twistedbird
05-21-2012, 08:48 AM
so even with all these upgrades its still not enough? whats it going to take?

kenewagner
05-21-2012, 08:53 AM
so even with all these upgrades its still not enough? whats it going to take?

A twin screw or turbo will give you a huge leap in power

Ken

XR7 Dave
05-21-2012, 08:56 AM
I think that with 15% OD you need a better intercooler. What is your peak ACT when on the dyno? What is the max ACT you see when doing a WOT run on the street 0 to 100mph?

twistedbird
05-21-2012, 10:16 PM
I havent check the ACTs nd i havent check my 0 to 100 i dont want to get dissappointed. This is what is boiling my blood i have a 2011 f-150 ecoboost that i just spend under 500 bucks for a k&n air filter no cai just filter nd a edge programmer nd pulled nearly 70 rwhp and 60 lbs of torque. I know the technology is different but their has to be something im over looking

hawgy
05-21-2012, 10:29 PM
i have a 91 sc with some new internals raised compression 8.8 to 1, 94 ported blower 15 % overdrive, mp plenum,db intercooler,some 60 pounders, 76 cnl, chip by dd, 2 1/2 dual in dual out exhuast, and its only cranking 255 rwhp. boost is at 14.8 psi
M I missing something or does that sound right. If anyone can shine some light thank u

how much tourqe is it doing?

twistedbird
05-21-2012, 10:46 PM
my bird is 331 tq and ecoboost is 440 tq

XR7 Dave
05-22-2012, 08:28 AM
I havent check the ACTs nd i havent check my 0 to 100 i dont want to get dissappointed. This is what is boiling my blood i have a 2011 f-150 ecoboost that i just spend under 500 bucks for a k&n air filter no cai just filter nd a edge programmer nd pulled nearly 70 rwhp and 60 lbs of torque. I know the technology is different but their has to be something im over looking

I wasn't suggesting that you time it, I just meant watch what the IAT does. This will tell you a lot about what is going on with the power. I recently put together a mild setup for my DD Cougar that makes just around 300rwhp with a very mild cam - now keep in mind this is a 5spd and I'm at about 600ft above sea level, but look at the power curve. The cam only has 210 duration and .491" lift so it's not a big cam but the power curve is what you want to look at.

I feel that one of the keys here is IAT. Mine didn't exceed 100 deg, granted it was 60 deg out that day and I have both a FMIC and alcohol injection. The alcohol injection actually hurt the mid range a little and probably helped the top end, but I feel that the trade off is worthwhile.

The important thing it to look at the curve and compare it to what you might have. If your torque curve is falling off before 5000rpm then you giving up power due to something being not right. Notice my torque isn't very high either, but keeping the IAT's down is key to letting the motor make power.

In my case I don't have any OD at all. I have coated rotors in an MPII and am making 13.5psi maximum boost. Since I don't have an MP plenum, I didn't want to add any OD because all that would do IMO is create cavitation at the blower and increase heat. I know you are at high elevation so that complicates things but this will give you an idea of what to expect.


On another note, don't get too hung up on other people's dyno #'s especially if they are from a long time ago. Dynojet software has changed over the years due to the fact that it was proven to be inaccurate. Dyno sheets from a long time ago can be very wrong, or even if a shop is still using the old software the same thing can happen today.

Another often overlooked factor is correction. Some dyno's are very aggressive with their correction factors. Looking at actual HP numbers can sometimes help. I remember tuning Todd Jelle's car in Denver. At 6000ft he was recording a corrected 427rwhp with his AR and CMSII motor, but the actual number was more like 325rwhp. Yes, the dyno was "applying" over 100rwhp correction.

All things to think about.

twistedbird
05-22-2012, 09:35 PM
so is it safe to say i need a better blower? better head work? and is 3.5 CIA a match with my C&l 76 running a orange tube and my 75mm tb

XR7 Dave
05-22-2012, 09:47 PM
I'd say until you can take it to the track and run an ET, the dyno #'s don't mean anything. I'd also like to see you post a dyno chart.

90sc35thann
05-22-2012, 10:53 PM
HP is just a number. Dave is correct. The proof is in the pudding. What times will she pull at the track? I had a 1991 mustang with a centrifugal and bolt ons. The dyno'd numbers were crappy at like 260rwhp. That car ran 12's all day long. I kept that set up for a while Until I wanted to go faster.

twistedbird
10-17-2012, 10:59 PM
Finally i took to the track car pulled 15.2 at 96 mph temp was 96 deg and I'm 5000 ft above sea. Does this sound reasonable?

Scott Long
10-18-2012, 02:04 AM
so you have a cam and ported heads, who did the porting? did you have larger valves installed?

What was your 60 ft. time? I understand you are at elevation higher than I would be at, and I'm going to be doing a similar build to yours, (76mm maf/ 75mm tb, late model overdriven blower, mp inlet, cam, 60's, 255) but I'm going to run a front mount, and big valve ported heads and port matched intake, still figuring out what I'm going to do for exhaust since my current system is going to be too small. I'd like 350 rwhp and mid 12's.

neverfastenough
10-18-2012, 09:32 AM
I'm 5000 ft above sea.

Was that the Density alt, or just the regular measured. No ones gonna make good numbers at that elevation

XR7 Dave
10-18-2012, 11:30 AM
Post your time slip.

David Neibert
10-18-2012, 11:37 AM
With that MPH, the car should be capable of running high 13s.

David

twistedbird
10-18-2012, 09:54 PM
let me find them nd ill put them up. Also the heads were ported here locally 3 angle valve job, stock valves wit heavier springs