Anyone have any real world data on a 305 with an HSR? I've been doing some searching but dyno #s are hard to come by for this combo. I have ported 416es, a stock 91 TPI cam (not the peanut cam) and a 305 TBI long block currently as well as a full exhaust system (headers with 2.25 dual merging into 3" single.)

I don't have #s on the 416es as I ported them myself, not sure if that's going to turn out to be a good or bad thing. Looking for expectations and what cam I should be thinking about for my next iteration of this engine. I'd like to be getting around 1HP/CID at the flywheel with this setup. Heck any 305/HSR combos would be great.

 

Curious in this myself. I have seen 196-200 whp posted for hsr peanut cammed cars but nothing posted from the countless threads asking what cam for this 305 etc. no one has results. I apologize but i cant remember his screen name who has the 305 hsr peanut cam setup but he is into autox i believe and it may have been a manual trans

For this reason i bought a 91 LB9 with the big cam option lol i will eventually do some cam testing from mild to wild, either on tpi intake, singleplane efi or hsr. I cant decide yet. Problem is i have no 700r4 trans to get real numbers i only have a th400.


I am willing to bet an L98 cammed 305 car should be up 20-25 whp on a peanut car easily. An L98 will do 240-250 whp often with hsr only swap thru auto trans. A 305 should be down 20-30 hp from cubes alone. Some of the LB9 1/4 times posting trap speeds 93-95 mph near stock leads me to think they are 220 whp cars thru manual in stock condition. I guess it will vary in condition

Cam on stock heads i bet can pick up 10-30 whp for most milder upgrades. Maybe more with a big stick. Heads just dont flow to really produce big numbers.

Edit: his name was zepher and it was a t5 trans 195whp 273 wtq

 

Yeah, I saw his #s, for some reason even with a peanut cam they seem low unless it just doesn't "need" that much flow the way it is.

Even the stock flow of a set of 416es should be good enough to hit 300fwhp and probably rwhp on a low loss setup without too much issue. In a way I'm more curious about how far it has to rev to get there. Next engine will probably have ARP rod bolts as a minimum.

GL figuring it out by the way. I'm thinking cam this engine up with something like the CC503 or perhaps bigger and seeing what it does. I'm half tempted to get a few flat tappet cams because they're cheap and try to figure out what I can get away with then find a finalized roller. Either that or just get something custom. I think that the HSR will like to have some cam to back it up.

 

Stock L98 cam with hsr on a L98 peaked at 5100 and had useable power to 5300, i shifted near that or 5500. A 305 with the L98 cam should pull 200-300 rpms higher. Hsr on a 305 should rev to 6.5-7k imo to really extract all the power. Torque will be lower and at a fairly high rpm. I think a 503 cam would be a very good cam for a 305 hsr. If you could get a good set of heads on it, i would love to see an xfi based lobe or high lift magnum lobe for alittle more control, closer to 230 deg. 280 xfi is awesome in a hsr 350, a 305 will be rough below 4000 rpm lol but be an absolute animal above 4000 to 7000 rpm imo.
I wanted to try a stock head cc305 or 306 cam to see what i could yank out of a stock longblock. 306 is huge for stock 350's tho so its probably overkill but you can get them for cheap on lt1 forums

 

I thought I read somewhere that certain lb9 with the manual trans and performance option came with the same came as the l98

 

Some definately did. Late 80's ones, i believe only the manual g92 option cars did. Once they went speed density, i thought 91-92 autos with tpi found in z28's got the L98 cam as well, but not sure. Need to check the history board and tech articles

Its a big difference, something like 30 degs of duration on the cam and .050" lift or more

 

I came across that when researching my old 88 GTA. It had every option including the g92 with the bigger rear brakes, 3.45 rear, and manual trans. With SLP runners, some base porting and a 100 shot of NOS it would dip into the 13s. still have the motor sitting in my chevelle

 

I believe all the 305 cars with manuals from 87 and on came with the 350 cam. And the autos had the peanut cam. At least from what I have read.

I think the reason you have a hard time finding data is because most people say they want to build a 305 and never follow through with it. Your venturing into somewhat uncharted territory.

 

If I could stop breaking stuff it'd be a lot more charted.

I've had this thing together and with 3.0 gears it was still an animal when running right. What's really cool is I have a 2 speed US Gear under drive setup so I'll be able to effectively test 2 gear ratios without changing anything.

https://www.thirdgen.org/forums/engi...oller-cam.html

Looking at this to get me started, I am really thinking even if it's not 100% right for $100 it would let me have a decent base line.

What are you guys doing for 2 pc timing covers on the rollers? From what my buddy who's researching this has said they all say "tappet only." Is there a reason for this? I'm thinking about busting out the MIG welder to resolve this shortcoming. REALLY not wanting to pull the pan every single time I want to mess with the cam.

 

If you're gonna do a 305, do it right. You've got a good start!

You know about mw66nova's old combo, right? He had lightly ported 416's and a 280H cam and made ~300ish hp if I remember right. Car went 12's.