Hey all, I finally descided on a complete Engine build up.

Here Goes...

Holley 670cfm TBI
Performer RPM Air Gap intake
Comp Cams Grind: XE284
World Products S/R Torquer 305 heads
Hedman Tork-Step Headers
and a nice fresh rebuild

After all this is said and done, desktop dyno claims...
339HP@6000
339TQ@4500

 

tbi-340
rpm air-200
cam-240 (?)
heads-370
headers-200
rebuild-270
chip (tbichips.com)-$30? (200-300 if you're buying your own stuff)

total = $1650
add to this misc parts and installation and you're pushing 2 grand easy.

If you've got the money why not buy a 350 HO engine, ive heard good things and its got about the same specs as your desktop dyno is giving you.

Just saying this b/c i was originally planning on doing something similar, untill i added it all up and thought about it for a while and realized how i just wouldnt be able to pull it off in a reasonable time frame.

just my .02
-chuck

 

If you get a n/a 305 to make 330 hp, then everyone on this board must be doing something wrong.
I wouldnt put too much stock into desktop dyno

Ken

 

That is WAY off

You do realize that you are adding about 160 HP to the car's stock rating......That's nearly double the stock rating.....

It's not as easy as getting new heads, cam, intake, TBI and some headers......It won't get you over 300 HP.....

Swap to a 350.....then mod that slowly.....It's better then doing a rebuild of a 305.....in the short and long run

 

I'm not going to beat you up as much as others have, but a few punches are in order.

That's way too much cam for a 305, for those heads, and for TBI.

Look more into something along the lines of the XE 250 or XE256. "On the street torque is king" (- John Lingenfelter) and you want to make as much with a 305 as you can.

Plus you can't run a lot of overlap with TBI or the MAP will go nuts.

Don't worry about the Torque Step headers. A 305 doesn't move enough air to take full advantage of them. 1-5/8" headers will be more than enough.

Just to give you an idea...

Using the XE 256 cam, DD2000 says a peak of 308 HP @ 5000 RPM.

Granted, that's a 31 HP loss, but it also says peak TQ is 358 @ 3500 RPM. 19 ft.lbs more at 1000 RPM less than the XE284.

The XE256 makes 344 ft.lbs of TQ at 2000 (the average stall TC used for the street). It also makes an average torque of 340 ft.lbs from 2000 to 5500 RPM. The XE284 averages 274 ft.lbs.

That's 66 ft.lbs more TQ from a smaller cam!!!

Here's the cool part.

The XE284 averages 250 HP from 2000 to 6500 RPM (500 over peak HP).
Using the XE256 the average HP from 2000 to 6500 RPM is 245 HP.

Only a 5 average HP loss, yet you'll gain 66 ft.lbs of torque.

That's what you feel in the seat of your pants. Plus you'll get better MPG.

All else being equal... it's a .217 decrease in ET according to Desktop Dragstrip shifting at 5500 RPM instead of 6600 RPM with the XE284.

The advantage there is that 5500 RPM is more within the air flow and fuel flow range of the 670 TBI.

As you can see it's very easy to over cam a motor. I can guarantee you will if you use that XE284.

 

Match the cam to the heads, that's all I gotta say.

 

Hey AJ_92RS, you got AIM? If so...hit me up at BadBlue91RS.

Also guys, I've changed my mind on the 305 due to the fact that I found a 400sbc in a 78 trans am for $500. I'm going to go with the 400sbc in the camaro and part out the trans am.

I've already devised a build-up for the 400 too .

 

That 400 most likely isn't the 400 you are thinking about. It's a pontiac 400, which will require a lot of modifications to work with your car. Find a chevy 400 block and go from there.

 

No, it is a chevy 400. No Poncho 400's in the 78 and up trans am's....not posative, but I'm pretty damn sure.

 

Just to set things straight, the Pontiac 400 WAS standard in the 1978 Trans Am. It also was used in a very limited basis in 1979, and then only with the WS-6 package/4-spd combo.

Just make sure you are dealing with the 400 (CHEVY) engine, as this was NEVER an option for the 1978 Trans Am.

I do realize the possability that it was installed by a previous owner though.

Hope this helps, and good luck with your swap.

 

http://www.superchevy.com/how-to/pro...-engine-build/

"Cant get 300hp from heads, headers and cam"... *Waits for the flamers to smash their keyboards after reading an article by actual engine builders on Super Chevy*...

You can increase compression to about 8.5 (dynamic) and be on the bleeding edge of detonation on 93 octane, on the aluminum trick flow heads, with a 0.58" lift cam, port and polish them, bore and stroke it to 334 or 339, forged rotating assembily, -3cc domes, light weight flywheel, windage tray, high performance bearings, and a 0.08" copper head gasket to manage the resulting compression ratios for pump gas, and put a pro-flow 4 XT EFI system on it with 42lb injectors, and get well into the 400hp numbers with ARP main cap fasteners to hold her together. We just put one of those together in the garage. 😂 You can go even higher on dynamic compression on a more agressive cam like a 292XFI, 5 angle valve job, run 115 or 120 octane race fuel, and an L98 procharger kit bolted to the L03 (305TBI block) at 8-12lbms and the numbers youll see on that dyno will approach 600.. Now spray it with a small 50hp shot of nitrus to keep it from killing itself by going too high.... Oh these "my first engine build" guys are adorable. Come to the drag strip pits, we'll show you how its done in the sub 5.7L race classes. Bring an extra set of pants, and maybe a barf bag... cuz its gonna be disghusting.

Oh btw, with the lighter rotating assembily of the 305 stroker blocks (vs the 383 L98 stroker), and with 7/16 studs and a 7/16 girdle, on an 800$ set of drag race hydraulic lifters and full roller billet rockers and chromoly high strength pushrods, your redline is now about 7500. But you could push 8000 if you really need to, just don't do it for too long (it becomesa hand granade). When you have a high rpm cam, a very good balance job (0.25 gram), and a valve sustem that can keep the high rpm stud deformation away, you can really get them to scream. Its worth mentioning though, at that point, you really need to consider machining the block for 4 bolt mains. 2 is really pushing it at 600hp on those gen-1 305 blocks.

Can they do 300+hp naturally asperated though? Oh the things a drag racing engine engineer can teach you... 😅 Hit the books, boys. Time to learn you some things. Now can a 383 make more? Well derp... But then you cant participate in the small bore endurance and drag races. A 334 or 339 can however particiate in unrestricted classes with stock stroke 350 and smash a lot of them. The look on your opponent's face when you tell them its an L03, LB9 or L69 block doing 9's on the quarter is effing priceless. Wait till you see how ridiclous they get when you do the T5 gforce rebuilds on 4.10 gears and small tire slicks... 60 foot times, anyone?

 

Can you dredge up a thread from the clinton administration next ? Feeling nostalgic today. Thanks.