Im trying to help a friend put together a decent 383. He's trying to show up his brother and he's thinking he needs totarget 500hp.

I told him he needed some GREAT heads a big roller cam, and I jsut didnt think he'd be able to do that with a 350, so I suggested he go 383.

So he's now in the process of building a 383. I suggested he go with AFR 195's, and since his block has factory roller cam hardware in it, I suggested he go with an xr282 cam, but I worry that's a little large for factory roller equipment:

http://www.compcams.com/technical/Dy...2HR-10_001.asp

.510/.520 lift.

I did some math from what a random guy on the internet said (had a hard time finding any relevant information as to the stock lift limitations) and it seemed like I ended up with .525 lift as the limitation. Clearly that would need to be checked after installation, but as Im helping him get this together, I dont want him to have any more speed bumps than necessary in the build process.

I also suggested he get H-beam rods... that should theoretically alleviate the need for a small base circle cam, right? I figure a small base circle cam would complicate the roller cam situation with the factory spider and dogbones. Will 5.7 or 6.0 inch rods allow for more cam clearance? And will a 3.75 stroke and 6 inch rods put the wrist pin into the compression rings?

So in summary...

1. AFR 195s - anything better for the money?

2. H-beam rods 5.7/6.0?

3. Comp xr282h10 roller camshaft 230/236, .510/.520

4. 383 bottom end

Getting the compression ratio set up and the quench measurements correct is something Im gonna work with him on, but since they're aluminum heads, and it's a 383, and the duration of the cam is 230/236, I figure I will keep it around 10.0:1.

He wants this to be a really fast cruiser... I want to get him something with a decent torque curve so he can street drive it. Im hoping this will get him that, and I was wondering what kind of horsepower you guys think this would make. This is pretty much the motor I've wanted to build for a while... so Im curious on two levels.

 

I have no experience building 383s, but it seems that I do recall people saying that AFR 195s are on the small side for a healthy 383. You may want to check on it.

 

Yeah I wondered if 195s or 210/220s would be better too, but I figured for a street car it'd be better to go on the small side. Would love to hear one way or the other from someone else.

 

Back up a minute.There just isn't a justification for a gen I .030 over block when the aftermarket blocks start at 4.125.About a $1.400 dollar investment will get you there.And the extra benefit of heavy duty everything.


I thought about this abit and want to add with the increase availability of LS donor vehicles,that almost makes more sense.

 

With the money he will be spending might as well go with an LSx... cam intake exhaust would be right up there.

Every head is different I know, and I have no experience with afr... but I have a set of pro-comp 210cc heads on my 383 with the xr288hr. That cam is the next size bigger. I would atleast go with the one I have. Still have enough vacuum for power brakes too.

I have PLENTY of torque. I am fully convinced there isn't a hill I cant climb in 5th at 1200-1500 rpm. That might be an attribute of my heads flowing less than an aft though... not sure.

To make 500hp I would go with a 210cc runner, and atleast xr288hr or similar cam, up the compression too. I am running 11.06:1... However, I have read that last point might only gain 10 or so horsepower.

 

Are you running the xr288 on factory roller lifters and dogbones/spider? I know the displacement can handle a larger cam, but I just worry about the factory roller stuff. If the factory hardware can handle it, that's what he will get. I might have him go 10.5:1, especially if it's an xr288 that we end up with. But it just depends on what pistons are available in his price range for his combination. I dont know what his deck height is yet or what length rod he will end up using, after that I will have a better idea of where exactly it should be. But since its not my engine and not my money, I dont want him on the ragged edge as far as compression goes, but I will make sure he has a healthy DCR.

I agree on the LSx thing, but it definitely complicates things on a lot of levels. His car is already set up with a carb, exhaust, transmission, engine mounts, etc for a Gen I block. I threw the LT1 swap idea past him too, since a running LT1 with a big roller cam can get you a long way... Not 500hp you know... but the more I talk about what it takes to swap some of the other options in, he'd rather just build something that bolts up as is. And an AFR-headed roller cammed 383 should give a lot of LS motors a good run, even if the engine itself is a little more expensive without accounting for all the swap-specific parts.

 

A 195 is plenty with that cam, a good I beam is all you need
Dont need a gigantic head to make 500hp

5.7 or 6" rods doesnt matter measure it all anyway before installing.
everyone freaks out about the pin location for some reason.
many "drop in " stroker rods still need clearancing in the block. Not a big deal.
Use a billet core if you can!

 

What leads you to believe the factory roller stuff cant handle lift? I've run .613 with 245 deg duration on exhaust side, and 230 deg with .603" lift on the intake side. My current cam for this upcoming year is over 246 deg intake, .640" on lift. Factory dogbones, LS7 lifters, etc

It will work just fine, and in my opinion, you need more lift than .510. Run 1.6 rockers, and even go with the 280XFI cam. Makes more power than the 282hr. AFR heads like the lift.

You should easily have 500hp with AFR 195's and 280xfi...or about that much power. There was a 195 headed 383 motor here a few months back that made near 520-530 hp or so with a smaller Jones custom grind, 228 deg I believe it was. Very nice cam.

What intake manifold will it run? Thats the more important thing right now

I agree, if you are already setup for it, might as well keep Gen I. My old 383 with AFR 195's ran mid 11's on motor alone and all the LSX boys were around that or slower with their heads/cam LS1 setups. Big 408 car was only running low 11's but he was alot heavier than my car. I havent been too impressed with LSx around my area. Bang for buck they can make some power and run decent ET's but to do a full blown swap for a cheap budget junkyard motor, doesnt seem worth it at that point. No reason you cant make a conventional head sbc run hard. My friends street efi 406 sbc runs 10.4's all motor, making 521whp. 9.4's on spray. Not many LSx guys in the area running that hard all motor

 

I am using facrory spider plate and dog bones with LS7 lifters. I am also wondering why you think lift is limited with them? I mean the only thing I can think of would be the flats on the lifter actually raising out of the dog bone. I am not sure what height that would occur, but I know guys like Orr89Rocz run big cams with them. If these guys say the 195 is good, I'm sure it is. Like I said I don't have experience with AFR, but it makes sense that their runner designs are so efficient that you don't need a big runner like other heads might.

And about compression, I agree with you. I was testing my luck going that high with compression. Luckily I am fine with 93 octane, but I am sure I am right on the edge.

 

I swear I read somewhere that there was a limit to how much lift those factory dogbones and lifters could handle. Glad to hear that it's not a concern. I think I'll have him go with an xr288 then.

I told him to run a Performer RPM intake, he doesnt have it yet so he can go single-plane if you guys think that's a better idea.. But I'm trying to pick these parts in a way that theres enough low end to get around easily and he can top out around 6000 RPM and get those big power numbers and still drive home.


I was mostly worried about having cam interference issues. I dont know how well those factory roller lifters can handle a small base circle cam, but maybe that's also a non-issue? Grinding the oil pan rail isnt a big deal and can be done until it clears. Can't just grind the camshaft down though.

 

195 AFR's with faster velocity ports will work great on a sub 6500 rpm motor and by that rpm on a 383, should be possible to make 500hp. 11 to 1 comp and a big cam certainly helps those odds.

If you wanted abit more power and more rpm, 210's would be a nice step up. Doing it all over again, I would have gone straight to the 210's but they are a 1206 gasket head and my HSR intake at the time was only 1205 with no room to port higher. Need to keep that into consideration.

IMO, for street build like this... not much due to 2 reasons. Out of the box, they have great ports with CNC process and feature lightweight 8mm valves like in LSx motors. Lightweight valves combined with their AFR 8019 spring, its a hydraulic roller cam dream! Not many out of the box heads feature springs suitable for aggressive hyd rollers and definately not many use light weight 8mm valves!

Only thing else that would be a better bang for the buck for your application would be a set of Profiler 195 or 210's. 210's likely best overall choice since they arent much bigger than 195's so they wont lose any torque or have air speed issues on a hot 350-383 motor. Get them through Chad Speier from Speier racing heads and he will do a basic port job on them to clean up the cast ports and custom match the valvetrain to your cam as required for 1495 or so. Its really a custom head for your setup at a shelf price. That about matches AFR stuff although you can get AFR's for around 1360-1400 with the upgrade spring. The Profilers with port job will have a better quality airflow curve however and have potential to support more rpm for more HP. 550hp would not be out of the question on a hot 383. Cam in the low 240's deg for a high high 6000 rpm peak.


EDIT: ported performer RPM type intake would work well and should handle 500hp. Single plane would work too, like a vic jr, port matched/cleaned up to the heads. Shouldnt have too much of a low end issue with the right converter/gear or with 6spd with gear. Much over 6000 rpm and a single plane starts to look reallly nice.

 

I just read an article in hot rod about manifolds. They said that the victor jr was a loss of about 2 or 3 ft lbs below 3000 but all the way after that the manifold made more power and tq. Considering that you really wont feel that tq i would suggest the vic jr. I second what orr said about the profilers and i would definitely suggest the 210's as well. They will give a little room to grow without much tq loss if any. Ive also read that Chad Speier is a great guy to deal with!

 

Anyone have any input on how to make sure the rods and cam dont try to occupy the same space?

 

I know someone who is selling a extremely low mile AFR 195's 64cc, and a custom grind roller cam around .579 lift
Part# HR72360-73360,
L/C 108
B.C. 1.140",
RR 1.52

Duration at .050"
Int: 232
Exh: 236

Lobe Lift
Int .360"
Exh: .360"

Lobe Seperation: 108
Intake Centerline: 106
Exhaust Centerline 110

If interested of course

 

If it were me I'd do it. But it's a buddy. I dont want to be like "hey buy from this guy that knows this guy who got in touch with me on the internet"

They should be an easy sell anyway.

 

I was speaking about my setup

 

That cam is a proven cam for 500+ hp in a 383 Seen Jones do a few grinds on similar engines and they all are around 500+ hp on good 195-210-ish cc heads with supporting intake