I got my 86 Regal with an Olds 307 and thought maybe I would run stock NHRA class but most things I've read is it's hard to get 15's in the 1/4 out of it. I have contacted cam companies about a stocker cam with .474 lift and lots of duration and only one said they need more information. Has anyone tried the Comp Thumper cams in this engine and it's a roller hydraulic.
Olds 307 Big Cam?
- Thread starter ronbz455
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I don't know much about cams but here's something else to think about: Your late '80s 7A heads and intake aren't very good for performance. If the rules allow it, you might wanna look into some early '80s 5A heads.
My 307 (internally stock) and some 3.73s got a time of 16.61 at the strip. That was without headers. It might be difficult but 15s should be do-able. Here's a clip of an early '80s 307 running 14s: http://www.youtube.com/watch?v=HbWxbKKnVTI
My 307 (internally stock) and some 3.73s got a time of 16.61 at the strip. That was without headers. It might be difficult but 15s should be do-able. Here's a clip of an early '80s 307 running 14s: http://www.youtube.com/watch?v=HbWxbKKnVTI
If you are looking to race it I would stay away from the Thumprs because they arent designed for power they are designed for noise. They have a lower lobe seperating angle which increases the valve overlap which in turn makes the car run like sh*t at low rpms but sound "choppy". So you SOUND like a racecar but thats it. I really dont understand why someone would buy these when they could spend alittle more to get a cam made for their particular application and have the best of both worlds. No offense to Thumper fans but its been proven 
That Olds running 14 wasn't radical or has a big stall. A 3500 to 4000 stall and slicks would probably get it close to 13's. I really don't need low end streetability because I will at least have a 3500 stall. In the GS that I race I have 542/535 lift, 344/354 adv, 272/282 Duration at .050 with 110 lobe center and it makes a .030 Buick 455 pull a 3500 lb car 10.80's with 10 to 1 compression. Yes it's radical but with the 5000 stall it Idles about 1200 and drives fine. Uses alot of gas though. But looking at the thumper cam cards with high stall and low gears, 3.73-4.10 it should run pretty good with some ported 5A heads. But I'm sure a cam grinder could do better.
Contact Bullet... I believe they do most of the 307 stocker grinds. Yes, you can get a "stock" 307 into the 12's, and a super stock style combo down deep into the 11's, but there are plenty of tricks involved beyond a cam swap. Venolia, among others, make stock legal pistons. You'll want more gear than 3.73 or 4.10's with that big of a cam. Do be aware that the windowed 307 blocks seemed to last anywhere from 50-125 passes when turning NHRA stocker rpm. Most of the guys have switched to sleeved DX or 350 solid main web blocks.
That's my car in the video... it's still on the CCC system with overdrive and has working air conditioning, so it needs low rpm torque. No doubt a bigger cam would go quicker as the engine doesn't pull over 5k rpm. It was meant to run that way, as the bottom end is bone stock. It would crack into the 13's off the computer with electric fans and the rear suspension changes I'm making, but I'm switching over to a BBO.
That's my car in the video... it's still on the CCC system with overdrive and has working air conditioning, so it needs low rpm torque. No doubt a bigger cam would go quicker as the engine doesn't pull over 5k rpm. It was meant to run that way, as the bottom end is bone stock. It would crack into the 13's off the computer with electric fans and the rear suspension changes I'm making, but I'm switching over to a BBO.
That's good to know. Right now I'm just goin headers, 600 or 800 Quad, HEI dist, non comp, 3.73, and later maybe my 350 trans and 3500 stall. If I break it or that cam cost to much I will probably get my 350 Buick together with, venolia stockers, hurst rods and big crower cam. I have a chance of borrowing a sheet metal intake for the 350 so I need to get it together.
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