LT1forever

iTrader: (4)

I was wondering if they still make the 847 cam. I was looking to run a larger cam instead of my current 503 cam. If not would my only route be a custom grind to achieve the same specs? Also would my 3.70s be enough gear to run the 847 or should I just step up to 3.90s? Any input would be greatly appreciated.

nitrous2fast

iTrader: (2)

being a manual car, even stock, i would have at least 4.10's. comp has a large selection of cams, as well as many other manufactures... is there a specific reason you want the 847??

LT1forever

iTrader: (4)

My goal is 400rwhp, with my current heads that might be a bit of a challenge. They flow 256 @ .600 but have a 62 cc chamber, so I'm losing a bit of compression. I dont have any real hindsight as to why I would like to run the 847. However I have always heard it was a top end screamer that put down good numbers.

96capricemgr

iTrader: (1)

Why box yourself into a 15+yo grind. Why not start a discussion about "this is what I have, this is what I want, please help me get there"?

As said 4.10s should be first with an M6.
I might consider doing heads before the cam, good heads will let a cam keep making power to a higher rpm.

stevo9389

the grind is available but it is under a different part number now. 19244485

LT1forever

iTrader: (4)

Well first off my goals are to have a legit quick street car, close to 400rwhp and running low 12s/high 11s. I would like to make the most of what I have without getting too carried away with cost.

I would like to have my heads milled to get my original 11:5:1 CR back, but I'm not really sure how much it would cost. I'm not even really sure what my CR is now with the Trickflows over stock heads.

I've had a few threads in the past asking about what route to go. Most adivsed me that my 503 cam is too small for a 383 and is holding me back quite a bit with my current setup. I would be making a handful of trips to the strip at most over the course of a year. The car would mainly just be a fair weather DD that could haul the mail when neccecasary. What would my most cost effective route?

96capricemgr

iTrader: (1)

So right now you have as cast 23degree trickflows?

The biggest gain you can make for that motor is porting the heads.
Sure the cam is on the conservative side but a bigger cam is not going to add the power porting could.

joelster

So you want him to port his Trickflow heads and keep the comp 503 cam? The comp 503 cam is all done by 6200. Lets say he sent his heads to AI for the 215c treatment, how much power do you think he'd pick up keeping that cam? I'd say 15 at the most.

I'd swap to a bigger cam like the XFI 468 or something similar from AI or LE. $300 and some gaskets and springs and you'd pick up 30-40hp. Plus you'd extend the rpm range quite a bit and make use of those gears.

I ran those same heads as-cast with the 468 cam on a stock shortblock. I can't answer your question about what your compression is unless you know the exact piston you are running, how far in the hole it is and the head gasket used.

supernaturalta

iTrader: (6)

Have you run your car at the track with the current setup? It seems like you should be very close to your goals already, unless you're trying to run those quarter mile times on regular street tires.

What is the cc of the piston valve reliefs?
What head gasket are you using?
What is the block deck height? (Stock is 9.025")

Most "cam experts" here are probably going to try and steer you into a cam that is too big anyway. Read some books written by real professionals on the subject and you'll get a better idea of what you want to do. Then, you'll be armed with at least enough knowledge to talk to one of the many available sponsored vendors here and guaranteed you'll get your car set up right.

joelster

There isn't a single book out there written by anyone with experience running an LT1 with its breadbox intake manifold, and a pcm cap of 7k. The vendors like AI and LE are well versed in how their cams make power on LT1 engines, or he could just ask in here and get replies from people that have run some of the same parts.

I agree that he should be close to those ET goals as it sits.

96capricemgr

iTrader: (1)

Far as I know AI wont touch his existing heads anyway so I was not pointing him that way. I believe they prefer to assemble bare castings for their 215cc Trickflow.

He mentioned taking them off for milling anyway, long as they are off might as well do the job right.

A cam upgrade would be good but, IMO the heads stand to gain him more.
I really don't think a cam is going to gain him 30-40hp over his already decent but conservative cam, I do think porting could get him that kind of gain though.

SS RRR

iTrader: (2)

I ran an 847 cam and dynoed 399.9rwhp and 360rwtq, but had valve float issues after 6200rpm with the same LPE heads I've had since 1997. I had 3.73's and street driving was horrible. Sixth gear was useless. It did pull 12.2's at the track, however given an optimal gear like a 4.10 or 4.30 it would been right around high 11's at full weight. I decided to scrap that for the current setup I have now. IMO there are better cams out there that make driving mannerisms much better. Regardless, if you are wanting that kind of power and want drivability you are most likely still going to have to step up to at least a 4.10 gear if running stock sized tires.

firehawk238

iTrader: (1)

I understand that the 847 is a dated "off the shelf" cam but one of my best friends is running that cam on his 383 into the low 10's. The cam sounds awsome and performs great. if that what the OP is looking the only concern id push his way is that he may not have enough volume of engine to really get the good out of the cam. also the cam likes to see high rpm's and unless you are going to push your motor well above 6500 you arent going to really get the goody out of it...

LT. DAN82

iTrader: (9)

DO NOT ORDER THE GM19244485. It is NOT for LT1/LT4. Just got mine in the from summit and it is not for this engine. Even went to Chevy today with the part number and checked with them. The 19244485 is for Gen 1 small blocks!

speed_demon24

iTrader: (6)

You were also running a single plane manifold which has a huge effect on the rpm range and your car is a tin can which helps with the lack of torque.