Avg HP on 427 SO

[priobe]

Hello all,
I am about to get my 427 SO back from the engine builder.
I am curious to hear what hp and torque # everyone is getting.
The motor is built :
compression 9.5 :1
ported Edlebrock heads
Weber intake match ported to Heads
Weber IDA 48
Cam Intake 245 @ .050
Exhaust 250 @ .050
Lift 650
LemansRoDS
Lemans Crank $
DOVE Rockers 1.72 ratio

[MidOHasp]

Probably about 300.

[MidOHasp]

Per Side.

[priobe]

I am hoping between 550 and 600 hp

[CJ428CJ]

I think that 9.5 compression ratio is a bit low and will prevent you from hitting your desired 550-600hp. A lot of people are running between 10.25 and 10.5 on pump gas with aluminum heads.

[MidOHasp]

I'm at 508 and had assumed that the bigger cam would help. But I'm running 10.25:1. 408cid. I guess that much cam with fairly mild compression doesn't yield quite what one may hope. Good point.

FYI...different motor, entirely, but I run pump gas no problem with 10.25:1 CR.

I figured 19 cubes and .068 more lift.....little more duration, properly tuned 48 IDAs.... bigger tube headers off those heads, you've got a chance to make 600.

I had originally written 250-275 for the first post but didn't want to catch a bunch of crap from you FE guys about how he had an FE, not a stroked Windsor.

Do you have desktop dyno 2000? Very cool program, generally pretty accurate if you have head flow profiles that match your own. If you know your true head flow, you can get pretty good numbers from DD2000.....

Either way, enjoy your S/O.

[FeWedge]

I did a similar motor for my 68 GT500. Ported iron medium riser’s,
428 crank, 11.5 compression, and of course the Webers.
My set up is the one off CSX3015. I bought it in the early 80’s
when they were restoring the car.
My cam has a little less lift but more duration. It made 605 hp and 625 trq.
I hope you have some experience with Webers or one of you friends does because it takes some tuning to make them work.

Rob

[priobe]

Rob,
My friend has some expierence with the Webers.
So you think it is possible to get 600 hp?

I felt the compression was low but the machinist told me it would be better because of the gas

[SCOBRAC]

9.5 will get you close to 500 no more probably closer to 475-485... Assuming everything else is as it should be.

[Excaliber]

12 to 1, radical cam, high riser head, dual fours.
665 horse with open headers. loose 96 horse with side pipes installed.

[RedCSX]

What size valves will you be running. My 427 center oiler which is stock stroked dynoed at 493HP. Pictures in photo gallery. I am guessing you make be close to me in the HP.

Morgan

[Cracker]

Hate to chime in on the bad news but there is no way your making that kind of power with that build except on dyno's in A _ _ _ _ _ _ S. I run 11:1 ported Ed. heads, big cam, Victor Single plane, Jessel Rockers, and balanced to true race standards. On a REAL dyno my logged 543 hp & 500 TQ. That's the reality. If you want big numbers with FE's it requires lots of $$$$ and compression. Enjoy the 425-450 you'll end up with unless you go to A _ _ _ _ _ _ S and then enjoy 650 hp.:LOL

THE OTHER PROBLEM is Webers like compression (real compression ideally) and don't like split duration cams. I hope your builder knows what he's doing. I also have a 428 w/ IDA's and know a little about the Webers as a result. Lastly, FE's (at least 427's) solid lifter motors run lifters with a 1.76 ratio - 1.72 in your build - I don't know. Best of luck!

[FeWedge]

I would say there is no way your combo will make 600. With your cam and depending on the ported Edlebrock heads , I would think you need be to in the 13 to 1 range. Why did you go with such low compression on a standard stroke 427? With alum. heads you can run a full point higher than iron.

Rob

[BB427]

I am going to take a guess and say your combination with Webers will probably not run as good as a stock 427 with a single 4bbl.

Cracker said it, Webers like timing, compression and very little overlap @.050. An I.R. setup has to be right.

Brent

[FeWedge]

I think you may be right. A good exhaust system helps. I am running a set of
Doug's Super Stock style cross over headers into a 3 1/2" down to 3" Dr. Gas
X pipe and 3" over the axle. Super free flowing. Much better than a Cobra side pipe.

Rob

[priobe]

Any suggestions on how to bump up the compression with take apart the motor fully


do you think it is worth shaving the heads?

[Excaliber]

Pump it up? I'm trying to loose a couple of points. going to a single four and perhaps a less radical cam.

450 or so horse is plenty!

[Cracker]

Priobe

Yes you can shave the heads as that is what I did to mine but one change always requires other checks such as: Piston to valve clearance, piston to deck clearance, intake to head ports (heads drop then so do the ports), etc. I still think it is worth it and with your combination I would go a full point to 10.5:1. It would be pump gas friendly and really help the Webers sing! When reducing the combution chambers a point can be made by reducing the size by 7 cc - I believe - someone correct me if I'm wrong.

At the rate were going we might, with changes, get you up to the high 400's!

Like Exc.... said before 450 hp is plenty that's why he has 675 but with the awe factor of Webers it feels like 650hp on visual appeal alone - it's the cat's meow!

[FeWedge]

With the compression ratio your engine builder told you have, you must have a reverse dome. Do you know what brand they are and what the deck height is? I would consider swapping pistons. Once you start milling there is no going back. If at some time you become tired of the Weber's and want to sell it, it may difficult to sell a Weber manifold that has been excessively milled.

Rob

[Keithc8]

I could only assume you were talking about us since we are in Arkansas and making more HP than most people that build FE's.
You name the place and time and we will be happy to go to any dyno you want to test engines.
I also feel that Super Flow would take offense to your comment as well since our Dyno is there newest SF902 Dyno like the NASCAR teams use. We have had two different engineers out, one fron Denver and one from the NASCAR teams to check our dyno because of the few cry babies that don't believe the power we make. I believe some of these people are loosing customers since we entered this cobre market a few years ago.
I did not start this dyno crap again Cracker did. Like I said before it is amazing how many people we have upset by delivering a quality product at a great price.
I believe if this engine is done right that about 550HP would be in line because of the compresion and camshaft. Good luck, Keith Craft