668.3 HP From Chev 377"!!!
Launching!
Joined: Nov 2003
Posts: 272
Likes: 0
Originally Posted by silverbeast
More Performance has a 406 on there site that makes like 725 hp. But the damn thing is 40 thousand dollars!! The sbc makes awesome power with the right stuff.
more performance is about the biggest rip off, con artists in North Carolina. they RIPPED my friend off of about 4,000$ and guess how much they want to build me a 347 SHORT block......... 4,700$ and thats with me doing all the labor and just bringing them a damn short block. they wanted 250$ to lower my vette... by cutting the freakin bushings. HAHA
Launching!
Joined: Mar 2004
Posts: 222
Likes: 0
From: Ontario Canada
Originally Posted by Karlo
"377ci is a de-stroked 400 SBC."
What does "De-stroked" mean? Good or bad??
What does "De-stroked" mean? Good or bad??
It's not anything bad. Its a 3.48" stroke crank from the chev 350 put into a 4.125 Bore 400 block which originally came with a 3.75 stroke. Helps with revabilty
TECH Addict
Joined: Mar 2004
Posts: 2,336
Likes: 0
From: Fat Chance Hotel
Originally Posted by Karlo
Karlo- a 377 is a 400 SBC block bored .030 (for a total bore of 4.155 inches) with a crank out of a 350 SBC (3.48 inch stroke; the usual stroke for the 400 SBC is 3.75 inches). It's a GREAT combination for a high RPM motor, as the large bore unshrouds the valves while the (relatively) short stroke allows for plenty of RPM without piston speeds getting out of control. It all depends on what you want to do with the car... for street driving, you probably want torque/power at lower RPM's (which means a longer stroke), 'cause let's face it... how much time do you really spend over 4000 RPM?? However, in a circle track or road race car where the engine spends a lot of time at high RPM, power at 2000 RPM isn't really a concern.
In any event, regarding the Factory5 GTM, it looks like it will be a hell of a car... I have been keeping up with the progress of it for a couple of years now. It'll use some bits off the C5 (control arms, spindles, brakes, fuel tanks, etc...), but a Porsche transaxle mated to a mid/rear mounted LSx. Full tube chassis, obviously, and by looking at some of the pics on the Factory5 website, it looks to be pretty stout (read: it has a moderately serious cage, including a halo and what looks like some door bars). F5 claims that the kit will sell for ~$20k... if that's the case, then I'll be on it like white on rice... just consider, though, that just the transmission is going to set you back some change (i.e., at least as much as a solid (but not out-of-control) motor).
In any event, regarding the Factory5 GTM, it looks like it will be a hell of a car... I have been keeping up with the progress of it for a couple of years now. It'll use some bits off the C5 (control arms, spindles, brakes, fuel tanks, etc...), but a Porsche transaxle mated to a mid/rear mounted LSx. Full tube chassis, obviously, and by looking at some of the pics on the Factory5 website, it looks to be pretty stout (read: it has a moderately serious cage, including a halo and what looks like some door bars). F5 claims that the kit will sell for ~$20k... if that's the case, then I'll be on it like white on rice... just consider, though, that just the transmission is going to set you back some change (i.e., at least as much as a solid (but not out-of-control) motor).
The LS1 can be destroked (if you want to use factory parts) by using a crank out of a 4.8L truck motor (3.27 inch stroke vs. a 3.62 inch stroke for the 5.3L, 5.7L LS1, and 6.0L truck motor/LS2). The problem is the large bore block... they are expensive. The LS2/iron 6.0L truck blocks have a 4 inch bore, which is obviously larger than the LS1's 3.9 inch bore, but to make the whole project really worth it, I'd go with a sleeved block/C5R block with a 4.125 inch bore.
Even then, you'd still want it in a light car and you'd have to spend a fortune on good rods and valvetrain if you really wanted to take advantage of it. All of that being said, if it was me, I'd go with the 4.125 inch bore block with the 3.62 inch crank... plenty of power to be made in that combination.
Even then, you'd still want it in a light car and you'd have to spend a fortune on good rods and valvetrain if you really wanted to take advantage of it. All of that being said, if it was me, I'd go with the 4.125 inch bore block with the 3.62 inch crank... plenty of power to be made in that combination.
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It looks like the transmissions can be had for ~$3k, but may need to be rebuilt. No telling what that would cost.
It looks like the transmissions can be had for ~$3k, but may need to be rebuilt. No telling what that would cost.
Teching In
Joined: Feb 2005
Posts: 2
Likes: 0
Karlo
The info supplied by Burnout re a 377 ci motor is quite correct, my engine was designed specifically for an Ultima type car weighting 2200ibs or less to be used with a Porsche G50 gearbox ... which has torque limitations so you cannot expect to use a big SBC 427ci type motor with trick parts 650ftibs of torque from 1000 rpm and not have gearbox problems ... as aot n car weighting so light does need the torque so so down
So a 377 gives you the power and torque higher up the rpm range, which limits the impact to the gearbox....
As was so rightly said the trick to my engine is the chapman race heads http://www.chapmanracingheads.com/p_home.asp which gave approx 90 bhp over a 23 degree config
The info supplied by Burnout re a 377 ci motor is quite correct, my engine was designed specifically for an Ultima type car weighting 2200ibs or less to be used with a Porsche G50 gearbox ... which has torque limitations so you cannot expect to use a big SBC 427ci type motor with trick parts 650ftibs of torque from 1000 rpm and not have gearbox problems ... as aot n car weighting so light does need the torque so so down
So a 377 gives you the power and torque higher up the rpm range, which limits the impact to the gearbox....
As was so rightly said the trick to my engine is the chapman race heads http://www.chapmanracingheads.com/p_home.asp which gave approx 90 bhp over a 23 degree config
Thread Starter
Staging Lane
Joined: Jan 2005
Posts: 75
Likes: 0
From: Boise, Idaho
World Record Holder!! I do not know if everyone on this forum knows anything about Gmans car but here is the low down!!
ULTIMA GTR SETS WORLD BEATING PERFORMANCE
The world beating performance figures obtained are:
0-60mph
2.7secs
0-100mph
5.5secs
0-150mph
11.8secs
30-70mph
2.0secs
0-100mph-0
10.3secs
100mph-0 Braking
3.9secs
Speed Achieved
204mph on the Bruntingthorpe straight
Top Speed
231mph est. (gearing limited)
Standing ¼ mile
10.5secs @ 140mph terminal *
Engine
Chevrolet V8 377cu in
Power
641bhp
Torque
545ft/lbs
Transmission
Porsche G50
See link for more info.
http://www.ultimasports.co.uk/
ULTIMA GTR SETS WORLD BEATING PERFORMANCE
The world beating performance figures obtained are:
0-60mph
2.7secs
0-100mph
5.5secs
0-150mph
11.8secs
30-70mph
2.0secs
0-100mph-0
10.3secs
100mph-0 Braking
3.9secs
Speed Achieved
204mph on the Bruntingthorpe straight
Top Speed
231mph est. (gearing limited)
Standing ¼ mile
10.5secs @ 140mph terminal *
Engine
Chevrolet V8 377cu in
Power
641bhp
Torque
545ft/lbs
Transmission
Porsche G50
See link for more info.
http://www.ultimasports.co.uk/
I have been keeping an eye on that factory five car for 2 years. I really like the changes that they have made to it. It is 20k for hte chasis, then you have to add drivetrain, fuel system, brakes and wheels. I hope to build one in the next two years.
