Benwb

iTrader: (1)

Hi,
I know you guys probably get plenty of these threads but here I go, Ive recently obtained a partially dissassembled LS1 that came out of a friends 99 FRC corvette. It already has katech rodbolts and a 224/229 cam installed(used with AFR 205 heads i believe..not included). Along with it i got a set of 853 heads(stock) and arp headstuds.
My question is, seeing what i already have what would be the easiest way making 400whp+- n/a. The plan for this motor is to convert it to a carb/distributor setup and put a 100-175shot on top of the 400. So would the 853 heads after being ported be good enough? or should i look at a different head combo?

Thank you for the help,
Ben

nghisus

Not sure porting the 853 heads would be as cost effective as getting a pair of 799 heads. Or selling the 853's then getting a pair of 799's and porting them. I think 243's area also a viable option. Read this:

https://ls1tech.com/forums/new-ls1-o...853-heads.html

BOBS99SS

iTrader: (2)

Does your friend wanna sell the afrs?

Benwb

iTrader: (1)

Im not sure, ill ask him though. If worse comes to worse i might pick them up, at least i know that'll even overshoot my goals.

Read it, Thanks for the link. Doesnt have that much info telling actual numbers. anyone know if these heads can possibly make around 400whp?

Thanks again,
Ben

nghisus

It depends on how much you spend on the port and polish but I don't know enough to tell you that specific head with port and polish job XYZ would make a certain amount of power with your specific cam. With enough money any amount of horsepower is possible. Yes, it is possible to make that kind of horsepower, maybe it might not be cost effective. The link spoke of the flow numbers and obviously the 853 is not as good as a design as some of the other heads you can get for not a lot of money. The "easiest way" would be to get a tried and true head and cam package from one of the vendors, it just might not be the cheapest.

Here's a guy with the same cam and AFR 205 heads:
https://ls1tech.com/forums/dynamomet...ottom-end.html

I think he had some tuning issues but his heads out flow the 853 buy a bunch and he's putting down power in the low 400's. How much money would you have to spend on the 853's to get there numbers even close to the AFR 205's compared to the ease of getting a set of 799's with a mild port? YMMV. Some guy may get on here and accuse me of talking out of my *** and say, "Hey, I made XXXX amount of horsepower with those 853's and yes they will work."

Benwb

iTrader: (1)

LOL! thats who i got the motor from, he's puting a katech motor in.

01ssreda4

iTrader: (96)

That motor should make 400 hp with the 853 heads. That being said I would not use them. For a few hundred bucks you can get a set of 243/799 heads. They should net you another 15/20 hp over the 853s.

Benwb

iTrader: (1)

Thanks! You mean ported correct? or do you mean untouched from the factory like i have?

Thanks again,
Ben

01ssreda4

iTrader: (96)

An 806/853/241 head will be outperformed by 15 hp by a 243/799 head just the way they came from GM.

nghisus

Where in LA are you from 01SS?

Benwb

iTrader: (1)

thanks, yah i understood that in your first post. I was just wonderin if in ur statement saying the 853's would make 400hp with my setup was with them stock as i have them or ported.

Thanks,
Ben

01ssreda4

iTrader: (96)

Im toward the NW end, near Shreveport

LS1s have no problem hitting 400 at the wheels with a decent cam and bolt ons with stock heads (853/241) and an M6. Its a little tougher for the autos bc they quite frankly don't dyno as well.

nghisus

Thats good to hear the 853's aren't as limiting as I thought they were. How big of a difference are a set of of ported 853's compared to stock 799's or 243's all else being equal. I understand not all porting is done equally so it might be a little tough to answer. I'm under the impression that dollar for dollar it's better to go with 799's versus porting 843's. Correct me if I'm wrong please.

Benwb

iTrader: (1)

Thanks for the info guys!