Hey all,

I have been wanting to build a badass engine for awhile and it took me some time to figure out that I just have to start somewhere, I wanted to build up a mean *** race 383 but because of the $$$ involved I'll be waiting 10 yrs to afford to do it all at once.

So I am going to build a more /budget/ minded motor with plans for a 383 in the future. I need some help and ideas on the camshaft selection. This is going to be a weekend warrior/strip car. (Just for fun - no daily driving)

Engine:
74' 355 2bolt - in machine shop getting worked over
Stock Crank/Rods - New ARP Rod bolts
KB 4.030" pistons (9.5:1, 10:1 at the very highest)
Pro-Lightning 220cc heads (big i know, but --> 383 future)
Holley Stealth Ram
TBI harnes repinned to TPI (730 Speed Density - Chip Tuning)

Drivetrain:
4th Gen Rear 10bolt Posi 3:42
700R4 - Currently STock
Vigilante TQ (Looking for 2800-3000 Stall)

Ok that covers the specs and what type of car i'm looking at it being. The two camshafts I have been looking at are the XE268, or XE274.

I know the XE268 would be easier to tune, but I have also heard good things about the XE274. And to mention the XE274 would start to sound badass

Would the 274 put the powerband out of reach for the stock crank?

Would the tuning be a nightmare on the XE274??

Any help would be appreciated, thanks!

 

Ok, where to start.

First, your StealthRam will have to be modified to work with the ProTopline heads. The aluminum Toplines ports are as tall as a 1206 F-P, the HSR is maxed out of material at a 1205. I had to weld material on the top of the HSR ports, then mill the face flat. Second, as you already noted, the 220cc heads are simply too big, especially when you are rpm-limited by the stock bottom end. As you probably know, the large volume of the intake runners is going to considerably slow the incoming air, causing a sluggish low end. Worse, the rpm range where the heads really shine will be above the capability of the bottom end. Plus a cam as small as the 268 or 274 is a real mismatch when paired with large runner heads. Anyway, Id recommend either using a better rotating assy with the 220s and a monster cam, or using a set of 190-195cc heads and something like the XR276HR. You could always get the heads ported if you ever need them for a more powerful motor.

What has to be done to an HSR to fit ProTopline alum. heads...

 

I like my cam, and would suggest it in your setup too! It will like RPM though. It sounds pretty rowdy, and pulls 3500-6000. I'm running a 3500 vigilante convertor and it works great on the street too (goes at idle). You may as well go big and then use it in the 383 when you get it built. No since buying one twice.

Charlie

 

Thats wierd I have heard of ppl using the HSR with Pro-Topline 200cc w/o mods before. I do agree the 220 are big and I would like to get Edelbrock E-Tecs but no HSR for vortec manifolds yet. Next option is AFR 195cc but = $$$.

What cam do you have Insomnicac?

The engine is actually in the machine shop right now and I haven't purchased the pistons yet. Anyone know where a good 350 forged rotating assembly that is priced decent - of coarse there lies the problem of if I'm going to do that might as well buy 383 rot assembly...

w/ say the XR276HR (which I like after looking at it) I think the stall for the converter ought to be at least 2500. Are the 3:42 gears ok or should I swap those out for some 3:73's while its sitting in the garage?????

Thanks for the help guys.

 

It seems to me that no one with the iron Toplines ever has any fitment problems. Maybe the port design is different between those and the aluminum heads, Im not sure, I havent seen the irons in person. Anyway, if you are putting together a SBC, there are millions of choices, dont get caught in the 'AFR or nothing' frame of mind.

 

According to summit's catalog the 180's and 200's are both 1205 gaskets, while the 220's to the 242's are 1206's. This is where people are having fitment problems, you have to weld ontop of the ports on a stealthram to run a 1206 gasket.

Charley's cam is a xe 280 or 282? not sure on the name but the specs are 230/236 on 110 LSA, and yes it lopes a bit .

I'd say go for the 200's now. 220's are going to be borderline for low end torque on a 383 anyway, and you can always get the heads ported out later. Ported 200's will flow better then the 220's and still have a smaller port.

 

Well you could try to use a 1205. But it covers up the top 1/8 in. of the port and the silicone sealing area of the gasket will not go around the port, its inside it. Summits a great place to buy parts, but seems somewhat lacking in the technical department.

 

So the stealthram will work with the Toplines but w/ a 1206 gasket?!?!

blah

Kinda off the subject but since I have an ASCD SS hood I might as well use the cold air coming in: has anyone rigged up a box to work w/ this hood and tpi????????

/or would it just be better to build a CAI...

 

No, an out of the box HSR will not work with a F-P 1206 gasket. You can actually see through the 1206 port openings when its held up to the Stealthram, theres simply not enough material. I posted a picture above showing what I had to do to make it work.

 

duh <---- had a dumbass attack. Long days at work get too ya sometime (long nights w/ a 2 month old too, heh)

I'll have to look into the difference between IRON and ALUMINUM. Right now the IRON is probably the way I would go due to the $$$. Yea I agree formularpm about the AFR's. Good head, but way overpriced imho.