I'm sticking with the stock short block but am having my heads and intake ported. I'm going to get a 58mm tb and 3600-4000 stall. This is strictly my drag car so what cams do you guys think would fit my application best?

 

you want a custom grind or an off the shelf cam?

 

I've thought about it and considered both. the off the shelf is cheaper but then you again you have to peice together the rest of the valvetrain yourself where the custom can just be ordered with matching valvetrain and you dont take the risk of missing key elements like the right valve spring and what not. The advantage of the custom grind is a application specific cam designed to your needs. I guess im just woundering if there is an off the shelf cam that will come close the making the same power as a custom grind and make it where i need it in the power band.

 

Gm847

 

Well thats one person that has the same idea as me.

 

847 for a RACE car, you have got to be kidding.

Step your stall up to the 5k range and do a solid roller, in the 255-265 area for duration and high 600's to low 700's for lift.

Just make sure you get some good rod bolts in it and that the oiling system is set up very well. Tell it to shift at 7000rpm.

Throw everything out of the car that it does not need to run and be raced.

Just best to ditch the hydraulic roller crap if all you're doing is racing, the solid roller will idle better and beat the hydraulic roller absolutely EVERYWHERE down the track and through the rpms.

 

On a stock shortblock? I wouldn't think that said shortblock would handle 7k for very long. But you do have alot more experience than I do and depending on your response, it might just change my mind about my build over the winter.

 

Stock shortblock is going to be the limiter as only one other poster ws smart enough to realize. Take this as a good leason about the "quality" of replies you will get on here.

Going to want to keep the rpms pretty low, say hopefully below 6500rpms. Meaning you can't use some huge duration cam like some began to recommend. What youcan do is get a custom cam setup for a big peak number sacrificing average power. In a race car you should be able to keep it between 5500-6500 the whole pass, meaning you do not need the average power most of us look for in streetable cams.

 

Depends on your end goal, IMO a hyd is a waste of time b/c you will end up wanting a solid anyway.

If its a race car might as well set up the bottom end like it needs to be also. If you seriously want to race.
Solid cam is so much easier to work with I think.

a 847 cam your going to be running 12's

 

GM847 = simple and proven performer and its not going to cost a ton in valvetrain plus it will last until he can afford to......
you think if he doesn't have the cash to build a good bottom end he's going to have the cash to piece together a proper solid roller valvetrain? Run a cheapo GM847 with associated valvetrain, you can probably find most parts used in the for sale section. save up your cash and buy the mahle powerpak pistons with some forged rods and reuse the stock crank. I wouldn't port the heads until you have a bottom end that can take the RPMs the ported heads will allow.

I also disagree that the GM847 will be running 12s. atljar ran 11s in a full weight 6 speed car. most GM847 cars put down 340-360 rwhp cam only, after that it is all car setup, you should know this as I know how well your car runs and you know its not all about power.

also, I had a custom cam specced for stock heads, ~3400 lb raceweight car, 4.10 geared, pt4000 stall, rpm range of 4000-7000. the cam that they came up with was a 242/250 on a 112. Its basically a GM847 on steroids (similar seat to seat valve events but the lobes are more aggressive past that.) I haven't been able to get it together yet due to the camshaft snout being wrong and not able to accept my vented optispark but I honestly don't see this cam making much more than 5 rwhp over a GM847... and I could have saved a lot of time and money going with the GM847. I also thought about the stock shortblock, which is why I don't have ported heads and put money into the shortblock. I would rather have the bottom end stay together and buy some ported heads later on than buy some ported heads and have the stock bottom end grenade. at least I would be able to drive the car while saving up rather than watching it sit like it has been for nearly 2 years.

 

IMO if he revs the 847 high enough to be truely effective he will destroy the shortblock. I am not saying it is a bad cam, just saying in a 350 it needs to rev higher than is prudent with the stock rodbolts.
Plus like I said this is a racecar he can afford to have a cam speced with a very narrow high peak and keep the engine around that rpm. For a cast Comp many places will do custom for the same price as off the shelf and even if you go with a top notch billet custom it is only $150 more which is not much when looking at heads and cam total cost.

 

I'm interested in a cam swap similar in nature to this, what other "shelf cams" are there that work in a 3000lb car?

 

if I build the bottom end to handle the added rpms what would be the best way of making the rpms with lets say a $1000 budget for just the bottom end and how much am I looking for in machining costs? My goal is to run 7.50 in the 1/8th which is the fastest allowed ET in my current class. If I'm faster than that thats no big deal I will just dish out the extra 20 bucks a week and try my luck with the big dogs in pro.

 

You'll have to excuse me, I took stock shortblock to mean blueprinted stock pieces with GOOD rod bolts. I would not race a factory assembled short block for any amount of money, you wont make it through the weekend. It needs alot of carefull attention to detail with the oiling system and clearances.

The stock pistons are probably marginal at that level but I have run higher than that with crappier pistons than the lt1 has stock. Like those cheap pos hyper claimer pistons people spend hours running at 7500rpm on the cirlce tracks all over america every week.

I'm also sorry I dont see **** about any shoestring lunch money budget here. All he said was whats a good drag cam for me.

I guess my definiton of drag car differs from the op quite a bit.

A cast cam is a poor choice for any roller regaurdless of shelf or custom. I refuse to do it the stress is too great, especially with how awesome comp is at ****ing up the hardening process and getting it too thin.

A solid roller cam will beat the living **** out of a hydraulic roller absolutely everywhere, and if it doesnt you need to fire your cam grinder. It should be up 20-30 hp/tq at the same rpm. Dont even have to worry about the solid cam floating because you can actually put enough spring on it to rev up without the lifter lifters collapsing and griping.

The biggest mistake anyone ever makes with trying to go fast is buying the same stuff twice. Race season is about over with here, save your pennies and eat pb&j over the winter and buy what it takes to do the job right.

 

good advice, I have bought the same thing multiple times. It gets old.