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motor hp seem right???

RootBreaker

RootBreaker

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Ok so I did a poll and got tons of choices... so I may have finally figured out which way I will be going...

playing with desktop dyno 2003 was perdy cool...

anyhow...
so I have a 1991 chevy 350 2bolt hydraulic roller cam/lifters
z-28 intake
holley truck avenger 670cfm carb
dual exhaust and headers
truck cant get out of its own way...

Engine specs in the caprice it was pulled from is
195hp/295ftlb torque.. supposedly
so my changes have changed it... but lets see if you think desktop dyno will be acurate...


$$$ to replace...
$150 - intake
$300 - heads (maybe getting a full 1998 350 for $300!!!! :bow: )
$250 - Cam
___________
$700 - about right? oh yeah gaskets...
$150
________
$850

so boy that is a pretty high number... I only have enough for the cam and intake right now :doah:
hopefully after ebay auctions.. then can get gaskets then save for heads

I am going to go comp cams xtreme 4x4 cam.. 08-411-8 cam (hydraulic roller)
vortec heads and performer dual plane intake

so I have a stock sheet
stock_9C1.JPG


bigger one if needed...
http://www.supermotors.org/getfile/246321/original/stock_9C1.JPG


all changes except for cam
TruckAvenger_DualPlane_headers_VortecHeads_9C1.JPG


bigger one if needed
http://www.supermotors.org/getfile/...Avenger_DualPlane_headers_VortecHeads_9C1.JPG


Worked with cam/heads/intake and all others...
Worked_9C1.JPG


bigger one if needed...
http://www.supermotors.org/getfile/246328/original/Worked_9C1.JPG


End result = barely over 300hp and 410ftlb torque??????????
are those numbers what I can expect? if so maybe save for a crate motor... $1200 = new motor and 325hp?????
 
Seems about right, crate motors usually perform slightly less than advertised I think. :confused:

I wish I had some of that software though, looks pretty cool
 
Well I played with Desktop Dyno 2000 and it was always off... If possible I would say save for the new motor. You will know its all new, will last, and if anything does happen, it has a warranty. How many miles does your current motor have? If it has alot of miles why rebuild the top end and have a 100K mile bottom end?? Also you will probably end up spending $$$ to have the heads rebuilt. If nothing else new springs.
 
neverendingproject said:
Seems about right, crate motors usually perform slightly less than advertised I think. :confused:

I wish I had some of that software though, looks pretty cool
Click to expand...


Hot Rod did a buildup of the 454 HO crate motor, GM rates it at 425/500, they put headers and a 825cfm carb on it and it made 467/576.
 
I was never impressed with DD2000. Way too much like fiction...

Rene
 
RootBreaker said:
End result = barely over 300hp and 410ftlb torque??????????
are those numbers what I can expect? if so maybe save for a crate motor... $1200 = new motor and 325hp?????
Click to expand...
I don't know anywhere that you can find a 325 HP crate motor for $1,200. :eek1: GM gets $2,400 for their 330 HP crate 350.
 
i would say go for the create motor. the 2 bolt mains arent very strong. and with the uped hp soming is going to break. so with the create motor you get the 4 bot mains and that is more than strong. that is what i would do

matt
 
The motor seems about right. Glad to see the newer version of DD does not think roller cams are the answer to everything. Try plugging in small tube headers with open exhaust (or mufflers) and watch the torque curve come up.

Can't get out of it's own way huh. I bet the lousy gearing of the 465 have something to do with that.

Save for a Big Block. With a name like Root Breaker, and comments like "Can't get out of it's own way", I would think nothing else would satisfy you.... :thinking:
 
SUBFAN said:
The motor seems about right. Glad to see the newer version of DD does not think roller cams are the answer to everything. Try plugging in small tube headers with open exhaust (or mufflers) and watch the torque curve come up.

Can't get out of it's own way huh. I bet the lousy gearing of the 465 have something to do with that.

Save for a Big Block. With a name like Root Breaker, and comments like "Can't get out of it's own way", I would think nothing else would satisfy you.... :thinking:
Click to expand...


I thought about the bb way... however if I get a complete bb then I basically have a motor that isnt too much better than what i could build.... $ for $
I know the 454 would be a good builder but stock what kind of numbers do they have?
say a 1998 chevy.... take tbi off and put carb on... will the numbers be way up there? if so I could see doing that...


and about the gears... I dont really wanna get into that discussion...

the cam in the motor is definitely not for my truck.. the truck lugs until it hits about 3000rpm's then wakes up and launches.... till redline @ 5500.....
just sluggish to the go.... I dont trailer my truck so needs driveability... I can go down the highway at 74mph at close to 3000rpms and if I had 5 whatever (as that is always everyones answer) I would be lucky to do 65mph at that rpm......
 
That BBC with a cam and headers will eat the SBC for lunch. The torque curve would be fatter and flatter, helping to get those 40's moving in the right direction....

The Sbc is more gear dependant than the BBC will ever be....
 
Well, I'm gonna mention gearing again. 4.10's and 40's are a lousy combo and are the source of your sluggishness. I run 4.56's and 40's with a diesel...same wide ratio SM 465.

4.10's...2238 rpm at 65 mph
4.56's...2490 rpm at 65 mph

More importantly is the torque multiplication better gearing gives you.

With 4.10's at peak torque

1st gear...4036 lbs of torque (3.58 1st gear x 4.10 x 275 lbs of tq)
2nd gear...1916
3rd gear ...1127

With 4.56's at peak torque

1st gear...4489 lbs of torque
2nd gear...2131
3rd gear...1254

If you had some 35's you could run on your truck for a day it'd give you near enough the same affect as swapping to 4.56's.

Rene
 
The stock tbi 454's only had 235 hp and 385 ft lbs at the tranny(carbed ones had 245hp and 385 ft lbs). Sure its more than an sbc but like rootbreaker said... $ for $ its hard to beat a built sbc when its done right and you do your homework. BBC performance parts are just about always 2x's the small blocks price. not to mention the extra $$ you'll be putting in the tank.

I agree about the gearing... my stock 350 couldn't climb a hill in OD with 35's. 40's is up in the 5.13 range.
 
tRustyK5 said:
Well, I'm gonna mention gearing again. 4.10's and 40's are a lousy combo and are the source of your sluggishness. Rene
Click to expand...


I need to change my sig... why do people think I have 4.10's????

MY TRUCK CAME FACTORY WITH 4.56'S!!!!1


I know a built 454 will produce more... hell a supercharged 570 will eat em all!!!! :haha:

you know one thing I didnt realize here.... If I change the heads and intake.. that is cool.....

Am I choosing too much cam by chance? If I have to do all this work to get vortec heads on... seems like not a mild cam then... I dont want a radical setup... 300hp or so.... or just something to get me rolling nicer...

If all this work needs to be done to get a .474 lift cam in then errrr are we talking a engine that gets 4mpg??? I dont want that... I want a machine able to go to the pits and back.. I may even decide to drive it from NJ to VA.... even bloomsburgh.... just dont wanna stop at every gas station...

Thanks
Jeff
 
dirtwarrior17 said:
The stock tbi 454's only had 235 hp and 385 ft lbs at the tranny(carbed ones had 245hp and 385 ft lbs)...
Click to expand...
But the cool thing is that the 454's hit max torque at 1,600-1,700 RPM. They make as much torque just off idle as a decent small block makes at 3,700 RPM. :cool1: With just a cam swap and a bit of head work the 454 torque will jump into the 450+ range. :bow:
 
found a different cam... maybe i was going for too much cam...

how bout this one...
http://store.summitracing.com/defau...-54760LUN&N=400421+308156&Nao=40&autoview=sku

Camshaft, Hydraulic Roller Tappet, Advertised Duration 279/ 287, Lift .447/ .471,

their tech support said that vortec heads will take up to a .475 lift cam... so the xtreme 4x4 being .474 is close.... since this is .471 then it should clear better???
 
It sounds like your truck doesn't make power until 3000 rpm eh?

With a big 4x4, I think that you need to be more concerned with torque than horsepower. Torque is what will get you over that rock, horsepower is what will get your speedometer pegged, lol

I built my engine to start making power at 1200 rpm, clear through to 5000 rpm. Since the truck idles at 800 rpm, it doesn't take long to hit 1200. Also, I built my engine for torque, not horsepower. I went with a tuned port setup (which has been a real pain in the butt!) that makes very strong torque until it runs out of breath at 4800 rpm.

Personally, in your case, I'd be looking to bump the compression ratio up, and get a bit of a smaller cam. Find something that'll produce stump pulling torque, which typically means a pretty healthy increase in horsepower too, and you'll probally be a bit better off.

Those 40" tires arn't helping much either, probally bringing your ratio down to like 3.08, lol (rough guess, did no math to come up with that number)
 
You're in a similar boat as I was.

I started with an SBC and 3.42 gearing and 33"s SLUG!

I started truck pulling and was getting SPANKED!!!!

My first mod was 4.56 gears and lockers (night and day difference) in acceleration and power with the gears.

I then tried waking up the SBC with a cam, heads (2.02 angle plug), intake, and exhaust. The truck was a screamer and did well, but no power down low (below 3000rpms).

I made the mistake of taking out my rev limiter chip a month or so ago and over-revved the motor on the street :doah:

I'm in the process of swapping in a mild 454 with stock exhaust manifolds and will let you know the difference. I'm heading to Indiana for a job interview this weekend, but I'm hoping to have it running and ready to go by the following weekend.
 
Sorry Jeff, I was going by your info in the link you used to have as a sig. I didn't realize you had swapped 4.56's already.

Rene
 
Depends on how much $$$$ your willing to throw at it... once your figure that out add another 1200. :D

Of course i still preech built sbc... having driven a stock 454 tbi i wasn't all that impressed. Yeah it had some GOOD low end tq but a built sbc will have the same kind of tq at that rpm...

for example i spent 3200 bucks for a 355 longblock with a custom tbi setup. But had i done my homework i could have swapped an old tpi system on there and saved about a grand. Thats a 330 hp and 390 ft lb fresh 355 with tpi for 2200-2500 bucks. That motor has around 370 ft lbs of tq at 2000 rpm. Sure the bbc will eat it for lunch if your talking all out buildup but dollar for dollar its pretty damn close. Say you use that extra 1000 for some darts and it would be more around 400 hp and 440 ft lbs of tq out of a fresh tpi 355 for 3200-3500 bucks.

A bbc makes you cool, but a sbc screamer makes you a giantkiller. ;) :D
 
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tRustyK5 said:
Sorry Jeff, I was going by your info in the link you used to have as a sig. I didn't realize you had swapped 4.56's already.

Rene
Click to expand...


saight wasnt bustin balls.... truck came factory with 4.56's however when I put the d60 in.. I had to replace the 4.10's
 
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