Small Block & Big Block Chevy Specific Mouse & Rat Motor Discussion & Conversions

Question about crate engines

Thread Tools
 
Search this Thread
 
Old Mar 1, 2006 | 06:48 PM
  #1  
jarednut4ever's Avatar
Thread Starter
12 Second Club
iTrader: (14)
 
Joined: Oct 2004
Posts: 269
Likes: 0
Default Question about crate engines

I just bought a 290 horse 350 from gm performance parts. It seems to be underrated. I can pull Lt1's pretty easy. Is it normal for Gm to under rate the horsepower of their motors. And if it is under rated what is the real dyno's of the 290 horsepower motor. Let me know
Reply
Old Mar 1, 2006 | 07:56 PM
  #2  
PRAY HRD's Avatar
9 Second Club
iTrader: (119)
 
Joined: Aug 2003
Posts: 2,972
Likes: 1
From: CISSNA PARK, IL
Default

yes, it's typical of basically All crate motor co's to under rate their power levels, as is the case with probably all vehicle mfg's. it's a safety feature for them so that nobody can ever claim theirs didn't make the claimed xxx hp they advertise. i'm not sure how much they under rate, but it's enough so that any variation from one motor to another is covered. let's say a company builds 20 motors. they're not all going to make the same power due to this or that, even with the exact same parts right down to the bolts. if 1 motor makes 300 on the low end, and another makes 315 on the high end, and the other 18 fall somewhere in between said high and low, if they advertise 290hp they are more than likely never going to have a problem with a customer if they should have an engine dyno at their disposal to check the claimed hp level and find out it's lower than they claimed, and now you're posting all over the net that they're f'n thieves, f'n liers, f'n whatever. sorry about the rambling, but does that make sence?

for example, i called up World Products a few years ago asking about a 540 that was said to make xxx hp, and he flat out told me it Will make more than that, but that's how they have to advertise. give GMPP a call and see what they say. they might have the avg. power that they typically see out of them.
Reply
Old Mar 12, 2006 | 11:17 PM
  #3  
NOVA's Avatar
Staging Lane
 
Joined: Sep 2005
Posts: 68
Likes: 0
From: Southern California
Default

So my new ZZ4 will probably have more than the 355 thats advertised,wow thats a good thing!
Reply
Old Mar 14, 2006 | 12:11 AM
  #4  
jarednut4ever's Avatar
Thread Starter
12 Second Club
iTrader: (14)
 
Joined: Oct 2004
Posts: 269
Likes: 0
Default

Ya I have been racing people. They are really underrated. In my 4100 pound truck I have beat a 95 LT1, a 1996 mustang GT, a 97 LT1 and a 2001 mustang GT. So I am leaning towards that it has somewhere near 320-330 horse.
Reply
Old Mar 14, 2006 | 03:46 AM
  #5  
TimTaylor75's Avatar
TECH Regular
15 Year Member
iTrader: (4)
 
Joined: Jul 2005
Posts: 417
Likes: 0
From: Columbus, Ohio
Default

Originally Posted by jarednut4ever
I just bought a 290 horse 350 from gm performance parts. It seems to be underrated. I can pull Lt1's pretty easy. Is it normal for Gm to under rate the horsepower of their motors. And if it is under rated what is the real dyno's of the 290 horsepower motor. Let me know
Maybe have it dyno'd and let US know
Reply
Old Mar 14, 2006 | 04:02 AM
  #6  
proxemics's Avatar
On The Tree
 
Joined: Jan 2006
Posts: 180
Likes: 0
From: saudi arabia
Default

yes please

and what is your trans , gears any mod ?
Reply
Old Mar 14, 2006 | 05:32 PM
  #7  
jarednut4ever's Avatar
Thread Starter
12 Second Club
iTrader: (14)
 
Joined: Oct 2004
Posts: 269
Likes: 0
Default

I have a 77 gmc sierra, th350 trans, 4.10 posi. stock motor with performer RPM intake, electric fans, x pipe with straight pipes. I am racing this weekend I will let you know how It runs
Reply




All times are GMT -5. The time now is 10:06 PM.

story-0
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-1
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-2
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-3
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-4
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-5
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-6
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-7
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-8
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-9
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE