I want to beat LS1's, 302 block or 347?

pwcracer

Founding Member
Jun 13, 2000
347
0
16
Hastings, MN, USA
I was just going to do the h/c/i but my block has 86k on it already. I was going to build another engine, and can't decide on a 347 or stick with a 302. I want this engine to be my daily driver in the summer, about 75 miles a day. Would going to a 347 kill my reliability and fuel economy? I was thinking of using afr 185 heads with the 347 setup.

Any thoughts with on this?

Thanks
 
86k miles is nothing for a 302. If you aren't seeing blue smoke when you step on it, or hearing unacceptable sounds from the engine, then rebuilding it now would be a waste of money.

A 302 with H/C/I can take a stock LS1. I haven't lost to one yet :).

Dave
 
That would save me $2500!

If I could beat them with just the HCI that would be perfect.
I had a post on here awhile back where I swore I wouldn't bring my stang out of storage unless it could beat an LS1, thanks to some idiot in a vette kicking my cars arse last summer.. Not to mention some Z28's..
 
It depends, some guys do it with more some with less. I have a 90K mile stock bottem end in my car and although a mild LS1 would kill me, stockers are right in my terretory. I also have stock heads with valves, stock cam and bolt ons.

I would say a good set of heads, matched cam, intake and bolt ons would put you well into LS1 land. But then again stock LS1s and modded are a whole new ballgame!
 
I agree. H/C/I on a 302 is more than enough. My friends 95 cobra, which I have driven many times, has a stock cam and stock cobra manifold, afr heads, 3:73's, and all the bolt ons. He smokes ls1's on the freeway and in the 1/4.
You should be able to hang with a mild-medium modded ls1's as well. However, if you run into a heavily modded ls1, you will definatly need the extra displacement 0f a 331 or a 347.
 
Scott_95GT said:
I agree. H/C/I on a 302 is more than enough. My friends 95 cobra, which I have driven many times, has a stock cam and stock cobra manifold, afr heads, 3:73's, and all the bolt ons. He smokes ls1's on the freeway and in the 1/4.

I wonder if those LS1s drivers can't drive. Stock I have seen them dyno around 330-340hp... I'm not calling bs but what does your friend run in the 1/4? Especially since you said he smokes them on the freeway it makes me think, because those cars have a nasty 2nd and 3rd gear.
 
Scott_95GT said:
I agree. H/C/I on a 302 is more than enough. My friends 95 cobra, which I have driven many times, has a stock cam and stock cobra manifold, afr heads, 3:73's, and all the bolt ons. He smokes ls1's on the freeway and in the 1/4.

Smokes? I'll say he MIGHT have a chance in the 1/4 due to the gearing but I have a hard time believing he walks LS1s on the highway. As soon as that engine hits 3 grand or so in 3rd gear... seeee yaaaaa. Especially considering he still runs the stock Cobra cam, which is a dog.
 
Hey guys, maybee I over exzagerated (spell check) by using the word "smokes" but has beaten a couple ls1's z28 by decent margins.
When he got those afr 185's, 30# inj./mass air, and a custom chip, his car absolutly turned into a monster. With 255/45 tires he ran LOW 13's at the track, clearly capable of high 12's with traction and good conditions. Maybee it's the dense, Northern California below sea level air.
Certainly a modded, properly shifted ls1 would clearly beat him.
 
Im gonna go against the crowd and say go for a 331/347 and the afr's you mentioned. Chances are the LS1's your going to run into arn't going to be stock. We mod our cars and so do they. Id hate to see you regret putting a combo together and getting dissapointed. But if money is an obstacle which to most of us it is. Then go with h/c/i and be done with it. A zex kit isn't that expensive just in case.
 
If he does a good HCI and gets into the 12s, there's no way he's going to be dissapointed, even if he can't beat a heavily modded ls1, they've got a 350 right?

besides, i think gas mileage on a stroker would be pretty bad. paul's running low 12s with his hci and gets better gas milage than me. also your 86k engine is nothing.
 
mackey said:
I wonder if those LS1s drivers can't drive. Stock I have seen them dyno around 330-340hp...
The vast majority of LS1's do not dyno anywhere near 330-340 rwhp stock.

And even if they did, comparing peak horsepower numbers gives you about 1/100th of the entire picture. Weight, gearing, power under the curve, etc.
 
mackey said:
I thought they were factory rated at 340hp. Must be flywheel. my bad.
Actually its 320 flywheel, and from my dyno experience most STOCK hit around 280-290rwhp. Those are C5s and SS's alike, ive seen one stock C5 put down 300rwhp but thats it. Second putting my very average H/C/I graph back to back with most Lid, catback, TB LS1s i have noticed they have slightly better low end, but i kill them inthe midrange 3,000-5,600 or so, then they usually make a their high rwhp number but its at like 6,200rpm. I would say the majority of the race is gonna be at the midrange rpm. I ahve whoopped on 3 or 4 stock LS1s, and beaten a couple with the usual bolt ons. Trust me, gears can give you a big advantage.
 
For the same $$ I could get a SC

Looks like Vortech dropped their prices and for about the same $$ I could get a SC. I know this has prob been talked about before, but it looks like I would yield about the same HP, for about the same price. 6 or 1/2 dozen to me thus far..
 
get the supercharger first IMO. i've walked many a stock and mild modded LS1. a friend of mine has a h/extreme cam/i and he is the only ls1 that can keep up with me. gears and supercharger will put you past them.

get the supercharger, then when you have money, do the h/c/i. at 86k miles your still in the engine's prime. preferably heads and intake first. the stock cam is actually a really good cam for a supercharged application.
 
Get the 347 and get it done. I drove my little 302 in the ground. When I put my 347 in the torque, wonderful torque, put a grin on my face that you could not pull off with a crow bar.

When is enough ever enough? Just go ahead and do it. My car was a daily driver for over two years. Not one single problem, except for buying tires.
 
Nucking Futs said:
Get the 347 and get it done. I drove my little 302 in the ground. When I put my 347 in the torque, wonderful torque, put a grin on my face that you could not pull off with a crow bar.

When is enough ever enough? Just go ahead and do it. My car was a daily driver for over two years. Not one single problem, except for buying tires.


Havent seen you for awhile!

Did you buy a fully built 347 that you dropped in, or did you build your own?
Im looking in the next 2 years to sell the Vortech, and use that money to buy a 347 Longblock (since I have stock heads). I know they run $5+K for the ready-to-drop in DSS and others.

Thanks
RC