Ok here's the deal...... a buddy of mine dropped off a whole bunch of parts at my house last weekend for me to assemble him a 383. The goal is that it has to hang pretty close or beat my old 427. That means at least 423 RWHP capped up on pump gas. OK, maybe a little less since he won't be carrying the weight.

It will be in a '65 Convertible with a 4 speed. It needs to run somewhere in the 11's in the 115-120 mph range at least. Maybe more if we're lucky! As you can see we're looking for a pretty serious street piece, but I think it is easily doable. NOS not allowed.

So since lots of folks here have already been down this road, I figured this is a good place to save me a lot of brain crunching!

What we have so far is:

350 4 bolt block .030 over, honed with deck plates and decked. I haven't mocked it up yet but I'm sure we are at .000 or maybe a little positive.
3.750 SCAT crank
5.7 rods- GM already have good bolts
KB Hypereutectics- Flat top with 7cc valve relief
It's already balanced

He got all this stuff in a good deal so we're going to use it.

We have a set of GM Phase VI Bowtie 23* aluminum heads. They used to be mine years ago. They were heavily ported (I mean HEAVILY) by AFR way back when. It seems like they flowed 302 cfm (I'm going to check them again soon) at .650 lift. They have 2.10/1.625 valves, Titanium retainers etc etc. Old tech,but nice stuff. They used to run 8.60's(1/4 mile) in a doorslammer heavily sprayed car. They have 55cc chambers.

He also has a new set of Hooker 1 3/4" headers.

So the choices are down to cam and intake selection.

As far as cam goes, we will probably run a solid roller. Not opposed to a good flat tappet, but we figure the roller will help out some. We only plan to turn in the 6500-7000 range max so it's kind of a tossup. We are going to have to address the compression issue, because at this point he is slightly over 12.0 by my rough calculations. So cam can be fairly radical. He doesn't mind one that's a little hairy and he loves to bang gears!

Intake selection is next. We have access to a brand new Accell Superram still in the box for a great price. It also has software with it. How high will those dudes turn on a 383 and what kind of power can you make? I'm willing to give up some peak HP for some of what I understand is some unreal midrange and driveability with them. I know some C-4 guys seem to go pretty fast with them. Do they really allow compression that high? How much cam will it tolerate?

If the Accell won't do what we're wanting, then we'll go back to carb and probably lower compression some with a little chamber work.

So what do you guys think? Any first hand experience with something like this? Still has to be streetable!


Jim

 

You've got a gorgeous vette! Convertible and a 427, too :cool: .

I'm by far no pro at building motors, but I have some info that may help. AFR advertises a 383 with their 190cc street heads & 9.5:1 compression to put out 517 ft. lbs & 503 hp all by 6000 rpms which is good for the street. The torque curve is pretty flat from 2500 rpms to about 4750 rpms. They're using 1 3/4" headers & their AFR intake #5029. 750 cfm Holley (0-4779) carb & MSD distributor set w/ 36` timing. The cam is hyd roller Comp Cams #12-433-8. This is all with 93 octane pump gas according to them.

Your heads are ported so I'm not sure how they'll compare to the 190cc street heads. Their smallest chamber offered for this head is 68cc and they have the standard 2.02/ 1.60 valves in them. If these old heads were able to run 8's in a heavy car, then they may do the trick :D .

Car weight: 3200 lbs.
Horsepower: 503 hp
Configuration: Rear Wheel Drive


--------------------------------------------------------------------------------

Results
Quarter Mile Acceleration: 11.703 seconds.
Terminal speed: 126.3032 mph.
Not sure of the cars weight, but this is close to your goals. :yesnod:

Results from: http://www.web-cars.com/math/qtr_mile.html


[Modified by SmokedTires, 5:55 PM 3/1/2002]

 

Jim

I'm no expert either, But I think it's safe to say that you wont have any problem running in the low 11's with slicks!

I get around 12.1 for your compression. This could be tough/ if not impossible on pump gas. There are some guys on the forum that run high 11 cr's though.

Good Luck

 

I'm running 11.55:1 right now. I have only recently gotten the engine back together and when running DataMaster I was logging about 8000 counts of knock over a 15-20 minute drive with 92 octane (highest here .. :rolleyes: :rolleyes: :rolleyes: ). There seemed to be a constant retard of .1-.2 degrees and up to 7 degrees with some load. I haven't taken it above 3.5k yet because I'm still breaking it in, but I might have a problem with detonation above 3.5k without octane booster. I added some octane booster earlier and it got rid of the constant .1-.2 knock and reduced the spike knock to around 3-4. I haven't pulled any timing out for the stroker yet though, I have a lot of computer work ahead of me. Gotta get the tranny done first though.

 

Oh, and yes, with 0-deck you're going to have around 12.1:1 compression.

 

To me that 383 has Crower Flat tappet wrote all over it mid 250's intake and another 6 or so on the exhaust.108-110 LCA and Victor Jr 2nd design manifold All assuming it has 3.70 + gears and compression is close to described.Another way to go would be 114 LCA and mid 240's another 10 on the exhaust with good gas.Would be one crisp revving SOG!Just my 2cents.

And on the Superram? Bad medicine! Will peter out in mid to upper 5k range.I don't think the runners will flow but about roughly"it's early" 68% of what the heads will flow.

 

Hey Jim, can you put my 540 together too? :lol: :lol:

I'm amazed at the help you give to everyone else. You're a good man!

-Joe

 

427HOTROD,
Are those American TT-D wheels?
What size?
What size tires?
Standard or offset trailing arms?
Any body mods to fit wheels and tires?
Thanks!

 

Thanks for the feed back everyone!!! I know lots of folks have built these things and as fast as technology changes on small block's it's easier to sponge off of other folks real world tests!

SMOKED TIRES-Thanks for the comments, it means a lot! Also thanks for the AFR info. I think my heads can hang with them as far as flow goes, but I believe they have a better chamber that would help me on the pump gas issue. I'm going to work with what I have but the cam recommendations are intersting along with their use of the 750 Holley etc. Strong setup!

GLOCK- Thanks for the real world numbers from your tuning. That helps me a lot. The counts you're getting are probably not noticeable to the ear, but could be killing the engine if left alone and full power was put down. Aren't computers amazing? That was the main reason I was considering the Super Ram. The ability to do some easy tuning and improved driveability. As you said, the compression is way too high. We used these heads before on 350's. One with 14.5 compression and one with sump pistons!! Talk about wide variety! Now we have all this 383 stuff, so we're going to have to open up the chambers some to get it down. Sounds like your 11.5 is pushing the envelope. What cam are you using in the 383? The same HOT cam?

Mountain Motor- You're talking the same numbers I am. I figure we can push it into the 250 something at .050. I always throw some more ex. duration on them to help with capped up exhaust. Same with LSA, probably 108 and lift in the very high .500's, maybe low .600's with the heads we have. I figure we can stand a little overlap to bleed off a little pressure, plus he likes a nasty little motor. He had a 106* circle track cam in it last and loved it. He will end up with a Richmond 5 speed before it's all over so he can twist it like it will want to be.

The 240* with the wide LSA would make a killer responsive long stroke small block wouldn't it? Gas might be an issue though unless I really kill some compression.

GRUMPY 55- I have American Torque Thrusts. 15x7". I had to use 1/4" spacers to clear calipers. My control arms are stock and I have 255/60's on the rear and 215/65's on the front. If you look close my rear fenders have small flairs on them. I have pictures of the car back to '71 and they were there then. Someday, when I repaint it, they will remain... I love them! The fronts clear fine on mine and on the car we're building the 383 for with the same combo with stock fenders. In fact this guy is so sick that after he replaced lots of glass on his car making it as perfect as he could before he painted it, he brought his paint guy 200 miles to my house to measure my flairs. He went back and cut the new fenders to build flairs! When was the last time someone INSTALLED flairs on a midyear!!

FLARESIDE- Sure , c'mon over!!! We'll have a party!! Think of the fun we can have!! Actually this is my best buddy from high school. He can build it himself easily but he keeps telling me he wants to have me do one for him. He says I get to pick the cam etc. Trusting soul isn't he?

Actually this could be my chance.... I sent a car to his paint guy to be painted once and told him to go down and pick out a color since he knows what I like! It turned out great, so now it's his turn to trust me!

He He He He......

Thanks for all the help and if anyone has more I'm awful appreciative!

Jim

 

Yes, I'm using the HOT cam. Once I back the timing off a bit, the 11.5:1 compression should be ok. I'm not going to be running it at WOT until I can get all the knock fixed.

 

GLOCK-So what kind of RPM range do you expect with the HOT cam? How much did the extra cubes and stroke seem to affect it?


SMOKED TIRES- Oh yeah I forgot..... it USED to have the 427 in it. It's now holding down an engine stand waiting for future duty. It now has a little 'ole 540" combo in it now!!!


PS- GLOCK--- I'm a 1911 man myself!!!

Jim

 

I expect probably 2500-5500 or 6000. The extra cubes deepend the sound of the exhaust that's about it, and the extra compression made it louder. I can definitely tell a torque difference though. No doubt about it.


[Modified by Glock'94, 11:51 PM 3/2/2002]

 

Well, I did a little investigative work on the heads today. They are ported out to 207cc intake ports and the chambers are 57cc these days. I couldn't remember exactly what they were and they've been freshened up once since I had them. But every port and chamber were dead on the money. Good work!

I believe they started out as 175 cc ports and 55cc chambers. AFR did lots of work on them! They have the head bolt sleeves in them where they ported through the walls and then installed sleeves. You have to use studs on valve cover bolts because the ports also break through them and cause a vacuum leak.

They have 2.10/1.625 valves.

I've got my work cut out to get the compression down some on these dudes. Actually will probably help it some once I unshroud those huge valves in that little chamber!


Jim

 

I came across this at AFR's website:Hydraulic roller cams typically experience valve float at 5800-6000 rpm because of their fast ramp rates. AFR suggest you upgrade your springs to AFR part #8032, 1.530 O.D. with higher spring pressures and use our Patented “Hydra Rev Kit” to reduce chances of valve float associated with rpm 6000 or higher. S h i t! I just purchased the complete SR+LPE 219 cam!
Mind if I ask what was the great price? Ya can send that in an IM if ya like.





[Modified by 89 Paul in cal, 3:01 AM 3/4/2002]

 

Paul in Cal...don't sell short you recent purchase. The SR/219 makes a great street/strip combo very capable of running 11's in your car; it just aint right for the combo suggested here.

 

Thanx very much for the reassurance RALPH. Lately I have seen a few posts around the forum to the contrary. BTW, I remeber you saying you wanted to sell some of your wheel/tires. Do ya happen to have something like John Panuzzo's current set-up(weld prostars: 3.5"fronts, 15x10" rears) or some rear slicks?

 

I hope you're not referring to my post in the C4 section stating the LT-1 intake is superior to the Superram.... which it is, but the Superram is a very, very good street/strip manifold..... you won't regret once you have it all dialed in.

good luck
Beach Bum

 

If you can figure out how to get the quench in the .040-044. and thermally coat your pistons and chambers like my 383 I think mid to high 11's for c/r are doable.

The low 300 cfm # makes your heads on parr with mine with my 2.08/1.625. Since you want to stay under 7000 rpm you don't want or need 250+ duration out of a solid roller cam. You could use a cam like mine with 240/248 with 1.5 @.050 .635/.644 with 1.65/1.6 mine is also 112 lsa For more race oriented maybe go a couple of degrees more duration intake with low .600 lift and 109 lsa.

I have considered a hotter cam, but then your extending the power range well above 7000.

Just a note to end on. I had KB.s in a 355 and the largest valve I could run was 2.055. They were the two valve relief pistons and I didn't want to tear it down for piston cuts. With 2.10's and big cam you might need to look at JE.

 

Getting the quench will be no problem. I haven't mocked it up yet, but I believe I may even have a little positive deck. I think they did some pretty good cutting on the decks.

The main reason we're talking 7000 rpm is the KB's. I'm not a big fan of them, though I know many folks use them succesfully. I like to just go ahead and put forged in and not worry about it. BUT..... we wheeled and dealed to get all this stuff and he is in the whole rotating assembly for about $250. Well actually I guess we can reduce that some because it also came with retrofit roller lifters and a TPIS small hyd. roller cam that we don't intend to use. We can sell that stuff to someone!!

I know, I know, it wouldn't have been so expensive but the block that came with it turned out to be cracked so we had to bore and deck another! We checked two other blocks before deciding we needed to use the one that currently was in his car since we knew it was good. Geez...come to think of it... I gave that one to him too!!! ;-) What can you do?? So we have a couple hundred in machine work too. It's already balanced and we polished the crank etc. Still std. size.

Thanks for the cam recomendations. That's a pretty aggressive lobe you have there. Pretty short duration and a good bit of lift. Did you have it custom ground? Have you dyno'd it? What is the curve on it? Where does it peak at? What kind of RPM does it like?

You know coating the pistons would be a good idea, but geez I hate to spend the money on hypereutectics. But as much heat as they hold in the crown, it would probably be more beneficial to them than some of the others. What's it costing these days to coat a set? He's really trying to lo-buck this thing as much as possible. But just like everyone else, he wants as much as he can get!!

I'm not a big hyd. cam lover, but we've even considered using the rollers that came with it and just using an aggressive hyd. roller. May have to rethink it some. I doubt it though.... I'm almost sure some sort of solid will end up in it.

I believe I can get the heads out to 62-64 cc which will get me in the right compression area.

These pistons have the single trough type valve notch. I'm hoping they clear the big valves. I don't know why I expect them to, they never fit any of the other motors without work either!

Thanks for all the input guys. I'm weighing everything you're telling me. Real life feedback is better than lots of computer work and guessing. Now I'm assuming all you guys have your combo's sorted out perfectly and the cams are working just as you intended right?????

Just kidding!!

thanks,


Jim

 

In fact... Beach.... you're one of the guys i know has made the Super ram work well. I'm sure it's not the perfect setup for a 4 or 5 speed car, but it would be a handful on the street in a C-2!!!

Jim