C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

383 HSR dyno'd

Thread Tools
 
Search this Thread
 
Old Aug 1, 2008 | 11:25 PM
  #1  
Orr89rocz's Avatar
Orr89rocz
Thread Starter
Burning Brakes
 
Joined: Jul 2006
Posts: 1,080
Likes: 2
From: Pittsburgh PA
Default 383 HSR dyno'd

Took my 383 stealth ram motor to the dyno. Had a rough street tune in it and took it to the track and ran 11.67 at 116 as seen in my other thread.

Baseline pull was close to the tune i had at the track but with less timing. started at 34 degrees and went from there but didnt gain power. it liked 34, hell it may want 32 which seems low but its cool
Either way the baseline was 387 and 365 whp/wtq. however that is peak torque at 5000 where the air fuel was starting to richen up. below that it was LEAN and had no torque. Already dropped to 350 at 4500 and goes down from there but i had no readout for that. I estimate my track run to have 375-380whp and 350ish lb ft torque but not a flat curve.

For those that dont know

383 11:1 compression, AFR 195 eliminators, mild ported HSR
BRE custom grind, 230/245 .603/.613 109 lsa
stock Camaro air intake/MAF sensor
Longtubes and 4inch single exhaust
3600 stall, 3.42 gears
Runs had converter locked up

Car was very hot. Drove there 180 degrees coolant and no time to rest. Put it on and went at it. started at 180 and finished at 200 degrees final pull so power was down from run to run alittle. true gains were not realized from run to run but some gains were noticed. Got the midrange air fuel down from like 16.5 to around 13.5. it may want more but thats where we left it for now

Midrange really shined. LOADS of torque gained. 20-30lb ft in some areas it seems. I am happy with it. FLAT curve from 3700-5000 rpms or so. Wasnt as high as i wanted but it will do for now.


SUMMARY
http://media.putfile.com/383-Stealth-Ram-dyno-run
BEST HP RUN my hottest run! run 10
BEST TQ RUN cooler run 8

combined SAE
392whp at 6250rpms
371wtq at 4000 rpms but its between 350-371 from 3600-5500 rpms, its pretty flat. SEE VID AND GRAPHS

click to blow up and then click to see full size




CONCLUSIONS

I got more in it with cooler temps for sure but i'm alittle upset. i thought i'd be nearer to 415-420whp but more importantly 400wtq. Just wasnt gonna happen today

I like the fat flat torque curve even tho i expected more from it thats for sure.
The hp peak rpm is around where i expected it to be and it flatlines for awhile so i'm happy with that... flat upper hp curve is what i expected this cam to do.

I also am thinking the 3" MAF and TPI intake is restricting this motor. I believe a larger intake flow path could help me and will be next thing to try

Also i wonder if my exhaust is hurting anything with its length. If cutouts at 18-19" from primary tubes end makes loads more power i'll know for sure that will be somethign for me to pursue. exhaust tuning

Also gotta fix the leaks in the exhaust..still have collector sealing problems

Last edited by Orr89rocz; Aug 1, 2008 at 11:28 PM.
Reply
Old Aug 2, 2008 | 12:45 AM
  #2  
Rich & Lisa_84's Avatar
Rich & Lisa_84
Melting Slicks
 
Joined: Sep 2003
Posts: 3,326
Likes: 1
From: I live at www.domesticlugnuts.com I sleep in PA
Default

Something seems to be holding it.
I would have expected to see both HP and Torque to be just over 400
Reply
Old Aug 2, 2008 | 06:51 AM
  #3  
Orr89rocz's Avatar
Orr89rocz
Thread Starter
Burning Brakes
 
Joined: Jul 2006
Posts: 1,080
Likes: 2
From: Pittsburgh PA
Default

i'm gonna try to fix some exhaust leaks and a bigger MAF/CAI setup to see if that flows more. IF that dont work, i'm not sure what to do lol. Maybe the exhaust length is killing motor even tho its capabable of flowing air since its 4inch straight thru, but one of the 3 inch y pipe tubes is crushed down alittle but i dont think it will make a huge difference
Reply
Old Aug 2, 2008 | 08:04 AM
  #4  
88BlackZ-51's Avatar
88BlackZ-51
Race Director
Photogenic
Photoriffic
Liked
 
Joined: May 2003
Posts: 10,749
Likes: 41
Default

420 rwhp is alot for a 383 with a HSR ontop. The reason I say alot is because your running an automatic. Isn't 420 rwhp around 515chp. I wouldnt of expected that much power with your combo, but I dont know. What are your impressions of the AFR's? Are they the 1040's? Did you flow those suckers?
Reply
Old Aug 2, 2008 | 02:46 PM
  #5  
LD85's Avatar
LD85
Race Director
25 Year Member
 
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Default

Impressive, and it sounds streetable to boot!

Congrats
Reply
Old Aug 2, 2008 | 02:48 PM
  #6  
vader86's Avatar
vader86
Team Owner
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2001
Posts: 62,153
Likes: 1,731
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Default

This is with 1.75" primaries and 1.6RR, yes?
Reply
Old Aug 2, 2008 | 02:59 PM
  #7  
Curveit's Avatar
Curveit
Drifting
20 Year Member
Veteran: Army
Active Streak: 30 Days
Active Streak: 60 Days
 
Joined: Feb 2003
Posts: 1,978
Likes: 2
From: San Antonio Texas
Default

In my humble opinion you've got too much exhaust duration for the intake duration used. AFR heads have excellent exhaust flow. I think a 6 to 8* spread would pick up the TQ numbers. What you've got is a NO2 or Forced induction type cam.

Reply
Old Aug 2, 2008 | 05:27 PM
  #8  
TOO_HOTTVETTE's Avatar
TOO_HOTTVETTE
Burning Brakes
10 Year Member
 
Joined: Sep 2003
Posts: 1,214
Likes: 0
From: Miami FL
Default

You're making good power....but isn't this motor in an F body Camaro? This is C4 Corvette related..how?
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-1

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
story-2

10 Things Every Corvette Owner Needs (2026 Edition)

 Michael S. Palmer
story-3

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
story-4

10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

 Joe Kucinski
story-5

How Much Horsepower Every Corvette Engine "LOST" in 1972

 Joe Kucinski
story-6

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
story-7

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-8

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-9

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
Old Aug 2, 2008 | 05:35 PM
  #9  
vader86's Avatar
vader86
Team Owner
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2001
Posts: 62,153
Likes: 1,731
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Default

Originally Posted by TOO_HOTTVETTE
You're making good power....but isn't this motor in an F body Camaro? This is C4 Corvette related..how?
For the 100 threads about HSR 383s we're going to see now that they make them to fit our cars.
Reply
Old Aug 2, 2008 | 06:18 PM
  #10  
1989TransAm's Avatar
1989TransAm
Racer
 
Joined: Oct 2007
Posts: 478
Likes: 1
Default

"You're making good power....but isn't this motor in an F body Camaro? This is C4 Corvette related..how? "

Because the motors are virtually indentical. What works in an F body will work in a C4 Corvette.
Reply
Old Aug 2, 2008 | 07:57 PM
  #11  
Orr89rocz's Avatar
Orr89rocz
Thread Starter
Burning Brakes
 
Joined: Jul 2006
Posts: 1,080
Likes: 2
From: Pittsburgh PA
Default

What you've got is a NO2
INDEED it was intended to recieve some juice It will sometime in the next 2 months after i get a 12 bolt rear

You're making good power....but isn't this motor in an F body Camaro? This is C4 Corvette related..how
YEP same parts you could have in your L98 C4's. Same ECM and chips. SAME MAF i believe as well. And with HSR intakes for C4's now, this is something you guys could achieve. Else throw on a miniram or w/e and see similar results


Yes i'm running a 3600 stalled auto but the converter was locked up so power numbers are not getting eaten up as much. Alitle more than a manual but i wouldnt say too far off.

The AFR's are nice heads. i got the 1040's with upgraded 8019 springs for the cam. Cam is with 1.6 rockers bringing lift over .600. perfect for AFR 195's. GREAT plug clearance on these heads and my hooker headers. #1 is only tight spot but still clear from burning boots/wire with 90 degree boots and standard plugs. 1.75" primaries on the headers
Reply
Old Aug 2, 2008 | 08:45 PM
  #12  
Beach Bum's Avatar
Beach Bum
Safety Car
20 Year Member
 
Joined: Feb 1999
Posts: 4,724
Likes: 16
From: Little Elm TX
Default

Thanks for sharing !! It is interesting.

The power is pretty darn good and about what I would have expected out of that set-up.

What is the raceweight of your F-body ?

Do you know if any of the Fbody racers have put the HSR on a 420-434 ci motor yet ? Results ?

thanks !
Reply
Old Aug 2, 2008 | 09:09 PM
  #13  
Orr89rocz's Avatar
Orr89rocz
Thread Starter
Burning Brakes
 
Joined: Jul 2006
Posts: 1,080
Likes: 2
From: Pittsburgh PA
Default

last year i was around 3450 with me in it. This year i have aluminum heads, aluminum waterpump, lightweight LT1 ministarter, and all the ac canister/stuff is finally out. I do have heavier oil pan, heavier/larger exhaust but thats about it. Not sure if the forged internals are much heavier but probly due to more stroke and rod length

add all that up i bet its near 3400-3420 with me in it and 1/8 tank of gas. thats the raceweight. This is on skinnies/slicks

on my C6 rims its a good 120 lbs heavier


i have only heard of one other Fbody guy with a 427 HSR car and i believe he was approaching 500whp. pretty nasty setup. I'll have to dig to find that thread.
Reply
Old Aug 2, 2008 | 10:18 PM
  #14  
Beach Bum's Avatar
Beach Bum
Safety Car
20 Year Member
 
Joined: Feb 1999
Posts: 4,724
Likes: 16
From: Little Elm TX
Default

Can I ask what your 60 ft was ?..... with your 11.67 @ 116, I'm going to guess a high 1.5 or low 1.6 ? Also, who's 3600 rpm converter is that ? PI is my guess ?

You have a good shot at 120 mph in good air, or at the very least 118-119.... probably have to wait until Sept-Oct to see the good air you're gonna want.

I think the HSR is darn good intake, now that C4's have a hood clearing viable option with USM's new HSR, we should start to see more of them over here...... I am seriously considering selling my MR II and buying one, but want to see how they do on a couple of big cube set-ups first.

I really thought the HSR was the clear winner of that SuperRod 383 intake shootout done a few years back that most are aware of..... MR had a few more HP, but the HSR easily won the mid-range torque battle and came very close to the MR peak.....

Thanks for sharing your results, they're appreciated by many over here.... or at least by me.
Reply
Old Aug 3, 2008 | 12:25 AM
  #15  
Orr89rocz's Avatar
Orr89rocz
Thread Starter
Burning Brakes
 
Joined: Jul 2006
Posts: 1,080
Likes: 2
From: Pittsburgh PA
Default

good guess. that run was 1.59. i ran another 11.67 at 115.x with a 1.62. I ran 11.77 at 116.0 on a spinning 1.66.

car will do bottom 1.5's if i actually launch it harder but i'm worried i'm gonna blow the rear

My converter is a Edge Racing Converter. used to be 2800 but i had it restalled to 3600. 9.5" street edge they call it, spec'd out to my motor combo and goals and it is very streetable. it doesnt act that big at all and will flash to near 4000. i cant complain
Reply
Old Aug 3, 2008 | 10:52 AM
  #16  
89FX3's Avatar
89FX3
Racer
 
Joined: Aug 2007
Posts: 252
Likes: 1
From: Ellicott City, MD
Default nice numbers on a nice setup

Nice numbers on a rough-tuned setup on a hot humid day in July.

I'm sure you'll see substantial improvement on a cooler less humid day.

Keep us posted.

Last edited by 89FX3; Aug 3, 2008 at 02:14 PM.
Reply
Old Aug 17, 2008 | 04:34 AM
  #17  
88BlackZ-51's Avatar
88BlackZ-51
Race Director
Photogenic
Photoriffic
Liked
 
Joined: May 2003
Posts: 10,749
Likes: 41
Default

Did you manage to iron out the tune a little bit more?
Reply
Old Aug 17, 2008 | 08:17 AM
  #18  
Orr89rocz's Avatar
Orr89rocz
Thread Starter
Burning Brakes
 
Joined: Jul 2006
Posts: 1,080
Likes: 2
From: Pittsburgh PA
Default

after the dyno tune i left it as is and went to the track again on similar conditions. it ran 11.53 at 118.2 on the same 1.59 60 foot. I cant launch it anyharder on these tires without spinning.

now i build a new MAF and CAI tubing and working on the tune all over again. not sure when i'll dyno it, but i will take it to the track this wednesday.
Reply
Old Aug 17, 2008 | 09:13 PM
  #19  
Vic'89's Avatar
Vic'89
Safety Car
25 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Jun 2000
Posts: 4,870
Likes: 25
From: Long Island, NY
Default

Originally Posted by Orr89rocz
after the dyno tune i left it as is and went to the track again on similar conditions. it ran 11.53 at 118.2 on the same 1.59 60 foot. I cant launch it anyharder on these tires without spinning.
Always takes me a good 5 or 6 times trips to the track to dial my car in with a new setup. So it looks like you are progressing well.

First run with my ZZ9\Miniram\Ported heads combo, I ran 12.4's. After a few more track sessions, I was down to 11.5's.

Good luck with it.

Vic
Reply

Get notified of new replies

To 383 HSR dyno'd





All times are GMT -4. The time now is 03:34 AM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-8
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-9
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE