RotaryMagic

I am wondering if someone will/has do/done this project... This would probably pull the wheels in 3rd with traction, but would make for some interesting power.

wwilliam54

isnt a 427 a modified 350??
if so then no prob at all, just expensive

wingsfan

Completely possible. You just need deep pockets. I was originally going to do just that on my LS1FD, but after seeing how little room there is for headers I'm going the forced induction route instead. It doesn't make much sense to build up a monster displacement block and then make it breathe through shorties or stock headers.

Most of the 7.0L setups I've seen top out around 550rwhp. For the $15K+ it would take to get me there the turbo route seems much cooler and has bigger potential.

Wyznewski

Isn't the 427 a big block?

turbogarrett

iTrader: (1)

no, people have bored/stroked ls1's to over 450 cubes.

jimlab

Originally, the 427 was one of Chevy's performance big blocks, with a 4.25" bore and 3.76" stroke (426.7 CID). Only in the last few years have 420+ CID combinations become more easily attainable with small blocks. Prior to that, an Olds Rocket Block was required (raised cam location) and the practical limit was 434 CID for a SBC.

Today, resleeved LS1 blocks allow 440+ CID displacements, and 454 CID small blocks are becoming more common, especially due to the availability of World Products' Motown SBC block. There is even a 476 CID small block combination available based on a Dart SBC block with a raised deck.

A Katech C5R 427 LS1 block is $5,000+ alone. A resleeved LS1 from MTI or Agostino in the 440+ CID range would easily set you back $20,000+ for a complete engine in the 550-585 horsepower range, not including computer, harness, and accessories, and I believe the 650+ horsepower 454 LS1 that Agostino built that was recently covered in one magazine was quoted as being in the $35k range.

Overall, it's a lot cheaper and easier to make big power with forced induction.

gnx7

iTrader: (10)

A "home built" LS1 stock block with forged crank/rods/pistons 348ci I believe recently on ls1tech.com used ported stock LS1 heads, LS6 intake, hydraulic roller cam and stock 6.0 truck exhaust manifolds pointing forward with a "rams horn" connecting the 2 into a T-88 turbo. It used aftermarket fuel management recently made 1150hp and 1050ft/lbs tq on an engine dyno stand with more left in it. Drag application obviously.... and unknown how long it will last at the track with full engine load.

It does show you what the potential of the LS1 is with some forced induction.

422ci LS1 would be pretty sweet and more than 500rwhp isn't really that usable in a streetcar anyway.

-GNX7

projekt

because 450hp isn't enough... :p

xchaos

I don't even know if I'm at 400hp, but with new street tires that are 275s out back and running on the street, I can spin well into 3rd gear...might even be able to chirp 4th. All that torque coupled with HP makes for a whole lot of fun.

I'm going to have to go to rear fender flares and some 12 inch wide rims with any more power...you could argue the point that I need them now.

peejay

I don't get why someone would go to the trouble of a raised-deck small block. They have them already, they're called BIG BLOCKS, and they have a slightly wider bore spacing as well so you don't need siamesed bores for greater-than-4.000ish pistons.

I can see the head gasketing issue, but Chevy solved that in 1969 with the ZL-1 package. Surprised the aftermarket hasn't grabbed hold of that and run.

jimlab

Weight advantage, especially in classes which penalize big blocks with extra weight.

For good reason; they're larger and they weigh more.

Grabbed hold of what, precisely?

peejay

Adding the two "missing" head bolts that are otherwise blocked by an intake port. The ZL-1 got around that by adding the two bolts and sealing each "perforated" intake port with pipe plugs.

Good point on the possible weight penalties. You'd think a 396 would be better to build than a 400 given that big blocks naturally have bigger ports (and more room to grow). More power can cancel the added weight, which is probably why they'd penalize it just for being a big-block.

I wonder what they do about engines like Pontiacs that don't have "big blocks" and "small blocks"? (Probably say "Pontiac? I didn't know they made engines...")

Thxbrett

iTrader: (1)

I am planning on doing the MTI 427 build up early next year. The pricing I got was unbeatable for the amount of motor. I already have got a set of MTI stage 2R heads coming now with a 224 cam and I will run that first. Then I will send out my motor to get the 427 treatment done. The total investment for the 427 is only around $8600 and totally woth the cash outlay. I will try to get the car in a few magazines next year running that set up.

Just got my AP champ car rotors today as well as my trailing arms, toe links and racing beat spoiler for my FD.
I called Brian today and he thinks my sub frames should be ready in approx 4-5 weeks. I hope this project comes together quicker than my last 3 which all took a minimum of 1 year each top get running.


Brett.

jimlab

For the bottom end alone, I assume.

Thxbrett

iTrader: (1)

No that is a complete built motor with the heads and a new cam. I already have a set of MTI stage 2R heads that need to be taken to stage 3 for the 427 build. This motor should make at least 520 whp on a dynojet.

Brett.

jimlab

With the heads and cam that were already paid for, correct? If not, I'd like to see a break down of that price.

Good luck.

Thxbrett

iTrader: (1)

Yes the price includes my heads redone from stage 2R to stage 3 as I mentioned in my last post. The break down Jim is as follows:

$6495 Block
$399 New Cam
$1000 Head work
$700 Shipping Both ways and insurance(approx)

As for 520 whp is there any reason the motor will not make this power Jim? I have been on the LS1 sites and it looks like people are making over 500 whp on these motors??

Brett.

jimlab

Unless you're going to be running a good sized solid roller cam, I wouldn't expect much more than 500 RWHP.

Here's one example...
http://www.racingflix.com/featuredride.asp?f=2

jimlab

BTW, that's with an S1 cam (244/244, .612/.612, 112 lsa). Yours is the C2?

http://www.motorsporttech.com/fbody_engine01.asp

Thxbrett

iTrader: (1)

500 whp in a 2800 pound car will be plenty for me! I am having a custom cam made for the motor, but I am not not sure about going solid roller or not.

As for the C2 cam that is what I am running with my stock motor and ported heads. I will not be running that cam on the 427, and will have my cam guy build a custom piece for that application. What cam are you putting in your motor Jim?

Brett.

jimlab

The cam in the engine at the moment is a 260/266 @ 0.050", 0.686"/0.686", 112 lsa solid roller. I'm stepping down to a new custom grind from Comp Cams in the 24x range, still solid roller.

Thxbrett

iTrader: (1)

Wow that is an aggressive cam you have there Jim. I am not sure what my cam guy will recommend for the motor yet, but I do want it to be streetable to a degree.

I still can't believe how cheap this car is turning out to be with the LS1 v8 swap. I am looking at a total of around $17500 including the car.

Car $4500
01 LS1 V8/Speed(20000 miles) $3100
MTI heads/ C2 Ca, $1350
99 RX7 tail lights $330
Racing Beat Spoiler plus paint $500
Gab Super R/Ground Control Coilovers $600
M2 Roll Bar $350
18x9, 18x10 Volk 57 Pro $1400
S03 Pole Position tires $900
AP front Brake kit $800
Front and Rear Sway Bars $350
Hinson Sub Frame/wiring etc $1850
Custom Headers, intake and exhaust $700
LS1 Edit/tuning $500

I can't wait to get the car finished later this year.

Brett.

xchaos

Don't be surprised when that $17,500 ends up at $20-22k.

jimlab

The first one was, simply because the advertised duration was only 30 degrees more than the 0.050" duration, which means the ramps were nearly vertical with very high lift. Pretty hard on the valvetrain for a street car.

The new cam from Comp Cams is 242/248 @ 0.050", and a bit less lift. It's a good street solid roller. Of course, the displacement, high compression, and gearing will all help. I shouldn't have any cam surge after tuning, and it should idle like a well-tuned CC306 hydraulic roller.

jimlab

Or more.