SL-C powerplant possibility?

J

Jonathan

I want to thank LBCportage. The graph is a great help. Eric McClellan has the 525. Do you have any idle issues with the engine and is it a very rough idle? Is the throttle too twitchy and is the car uncomfortable to drive because of the quick torque curve?

These are the concerns I have and was wondering what your experience with the 525 has been.

Does anyone else have the ls376/525 and if so what has been your experience?

Thanks for all of the input.
 
Big-Foot

Randy V

Moderator-Admin
Staff member
Admin
Lifetime Supporter
JR - please abide by our rules and use your real name here on GT40s.com

You can change this from the User Control Panel "User CP" at the upper left quadrant of your screen.

Thank you..
 
E

Eric McClellan

JR2015 said:
I want to thank LBCportage. The graph is a great help. Eric McClellan has the 525. Do you have any idle issues with the engine and is it a very rough idle? Is the throttle too twitchy and is the car uncomfortable to drive because of the quick torque curve?

These are the concerns I have and was wondering what your experience with the 525 has been.

Does anyone else have the ls376/525 and if so what has been your experience?

Thanks for all of the input.
Click to expand...


Idle is fine, I guess I don't know how to answer that. "rough idle" to me indicates a problem, which there is no issue. It's got a bit of a lobe to it so you can definitely feel it, but I like that.

It's not going to be a soft idle like that of a daily driver, if that's what you mean.
 
J

Jonathan

I am planning to use my SLC mostly on the road. How is the throttle response on your vehicle? Is it twitchy and tough to make it a comfortable ride on the highway or is a great cruiser as well as a awesome performance car?

Thanks.
 
L

Scott Davis

Another suggestion if you are concerned or want to improve driveability (and get some additional HP maybe) is to get a tune. Many think that because you buy a crate motor and a ECU from GMPP that they will be run perfectly in reality the tune is "close"(some better then others for some reason). Many may view getting a dyno tune as defeating the purpose of going this crate engine route but there are definite improvements to be had (and also depends on your budget and concern about warranty). Food for thought.
 
E

Eric McClellan

LBCportagee said:
Another suggestion if you are concerned or want to improve driveability (and get some additional HP maybe) is to get a tune. Many think that because you buy a crate motor and a ECU from GMPP that they will be run perfectly in reality the tune is "close"(some better then others for some reason). Many may view getting a dyno tune as defeating the purpose of going this crate engine route but there are definite improvements to be had (and also depends on your budget and concern about warranty). Food for thought.
Click to expand...


I threw mine on the dyno to test for leaks and breakage and look at how the ECU was performing.

In my case it was dead on. It's been my experience that they come a bit rich, but mine was right-on perfect right out of the box.

Not only that but it made 524.5HP... I got robbed of 0.5 HP!!! :D
 
KENS80V

Ken Roberts

Supporter
You can get a cam spec'd for your exact application for a $25 fee. Pat G on ls1tech is famous for his custom cam selection. My LS 427 engine has a cam spe'd by him. He uses exotic cam spec programs and hundreds of previous proven combos to come up with a cam designed for your intended use based on gearing, weight, tire size, intended use, compression ratio, cylinder head design, piston design.....etc etc. He comes highly recommended.

The GM hot cam in the 480hp crate engine and the ASA cam in the 525hp engine have been around since the nineties and weren't even designed for LS3 engines. It just so happened that they worked pretty good in them. You can get slightly better horsepower numbers and slightly better drivability with a custom cam spec'd to your car. He gives you the spec sheet and you have Comp Cams grind it for you. This is all done through the likes of Summit Racing for about $325.
 
Last edited:
S

Mike

I have the GM crate LS376/480hp mated to the G96.50 box. Regarding the GMPP factory ECM tune. It's pretty good and like mentioned, maybe a little rich (thick warranty). After several pulls - chassis dyno 431hp/421Tq at the wheels on a dynojet. The GMPP supplied ecm with tune for this motor is dependent on you following their install directions precisely - meaning intake tube sized and MAF installed where they tell you to. Be aware that GMPP has certain hidden parameters in their tune that the aftermarket programmers at HPtuners/Elflive may not know about/have access to. As parameters are discovered the A/M tuners are adding these parameters to their software. IMHO -Aftermarket tuning may be helpful if your experiencing certain issues or need to change certain operating parameters, but it is not the silver bullet. If you're not worried about street drive-ability and just going racing - have at it. Reason for this caveat - good tuners are about as common as finding a real unicorn.
 

Attachments

  • dyno results .jpg
    dyno results .jpg
    201.6 KB · Views: 248
Last edited:
R

Bill

Mercury just announced that they will be selling a "QC4" crate motor. It is a double overhead cam motor with twin turbos that produces 1350HP on pump gas (1650HP on racing fuel). The down side is that it costs $55k.

The PICs below are the QC4 mounted in an Ultima. Notice that they reversed the intake manifold. If my calculations are correct, that Ultima has power to weight ratio of about 1.5lbs per HP!

engine-in-car-feature.jpg


mercury07.jpg


mercury02.jpg
 
G

James

I'm surprised no one has mentioned the AJP8 from the TVR.

The engine is REALLY light,, like around 267lbs. How is it that no other "streetable/affordable" V8 is nowhere near that? I'm not mentioning the Hartley,, because it's tiny (2.6L),, expensive ($35k), and needs to be rebuilt very often.

The AJP8 is

267lbs, SOHC, 4.5L Flatplane V8 making 420HP. Granted that's not a huge amount of power, and could be tweaked,, and if you think about it,, if a couple of guys in a small plant can make that much power out of an engine with no variable valve timing, how much could they make with modern day tech and keep it that light (or close,, figure in another 20lbs for variable valve timing and direct injection?
 
Last edited:
B

Les

Another engine from Ford:

"Ford Performance is now offering an EcoBoost Mustang 'power package' (an engine calibration and cold air intake) gives the four-cylinder 25 more peak horsepower and a whopping 70 more lb-ft peak of torque. That brings numbers up to 335 hp and 390 lb-ft. You might notice that the torque number is just 10 lb-ft away from the stock Mustang GT. While those are the peak figures, there's other nice gains throughout the band, including as high as 100 more hp at 6,000 rpm.

All of this could be yours for the price of $699."

V8 power without V8 weight: go faster! :thumbsup:

This is from autoblog.com. The four-cylinder Ford Mustang can produce nearly V8-level torque for $699 - Autoblog
 
V

Justin

Bassanio et Portia said:
Another engine from Ford:

"Ford Performance is now offering an EcoBoost Mustang 'power package' (an engine calibration and cold air intake) gives the four-cylinder 25 more peak horsepower and a whopping 70 more lb-ft peak of torque. That brings numbers up to 335 hp and 390 lb-ft. You might notice that the torque number is just 10 lb-ft away from the stock Mustang GT. While those are the peak figures, there's other nice gains throughout the band, including as high as 100 more hp at 6,000 rpm.

All of this could be yours for the price of $699."

V8 power without V8 weight: go faster! :thumbsup:

This is from autoblog.com. The four-cylinder Ford Mustang can produce nearly V8-level torque for $699 - Autoblog
Click to expand...

That makes sense in a lot of ways, especially if it is 100 lbs lighter than a V8. (Thats a big IF). IF I go with an SLC, I would rather look at alternatives than the good old V8. I love V8s. But all I think of when I hear a small block Chevy rumbling, is a Camaro or Corvette.

Edit: Engines like the 4G63 can be built to run 8k rpm and make over 500 hp reliably for the same price as a LS525. So really, its kind of a wash between them. The major advantage of the V8 is torque down low.
 
You must log in or register to reply here.

Similar threads

J
A Few Specific Questions For An SL-C Build
2 3
Replies
53
Views
9K
EFNFAST
E
C
Traveling with SL-C
Replies
9
Views
3K
Bassanio et Portia
B
T
How the OV-2s got to Vietnam
Replies
8
Views
3K
toy264
T
P
SL-C Build in MA
Replies
15
Views
6K
EFNFAST
E
A
New to the world of the SL-C
2 3
Replies
41
Views
5K
gt40fran
gt40fran
Back
Top