Cascade Crew

redlava · Posted: Thu Jun 05, 2008 6:51 pm Post subject: head swap question

I am looking for some different heads to put on my 350. The heads the previous owner used were smog heads from a 350 truck in the 70's. I do not want to use the vortec heads, because of the different intake and I am on a budget. I have found some L98 heads on craigslist that I am thinking about porting myself and using. How much power can these heads make once they are ported and matched with a decent cam? Is there a better head I should look into? If there are better heads what cars would I find them on?

Twilightoptics · Posted: Thu Jun 05, 2008 7:14 pm Post subject:

Vortec is about your next step up. Ported L98 heads flow pretty good. You gotta find out what chamber size your current heads are. So you know what you're doing to your compression with L98 heads. Plus you should find out what your piston to block deck height is. Another factor in gasket selection.

Quasi-Traction · Posted: Thu Jun 05, 2008 9:05 pm Post subject:

how much are you looking to spend on heads?

http://www.competitionproducts.com/prodinfo.asp?number=4361KA

they list them as a quantity of 1, but that's the price my catalog lists for a pair.

Seems like a pretty good deal.

Also....you may have to elongate the two center bolt holes on the intake with the L98 heads. I just had to do this with pair of 87+ Swirl port heads to get my intake to fit on.

redlava · Posted: Thu Jun 05, 2008 9:20 pm Post subject:

the old casting is a 462624 when I looked this up they have a 76cc chamber. I did not really want to spend that much on the heads. As of right now the initial head cost is 40 dollars. I am going to run a comp cams XE 268 flat tappet cam.

Another question I just thought of is that when me and tony raced we were dead even. Would the L98 heads even provide more power then my current set up. Maybe I should just save and buy new after market heads to avoid machining costs.

My set up is
edel performer intake
jet q jet
heddman long tubes and 3 inch exhaust
3.27 gears
and an unknown cam

Twilightoptics · Posted: Fri Jun 06, 2008 6:34 am Post subject:

I'd go with the XE262 cam myself. On that note I'd actually pick a Voodoo of similar duration and size. A solid even. Those XE cams are HELL on cylinder head seats.

L98 head will bump your compression up 1 Full point.

I don't know the rest of your specs so I can't tell you home much. Don't know what piston volume you have etc.

Where did this motor come from? Do you have a casting number? Was it rebuilt?

If it's like a st ocker you'll go from 8.5 to 9.6:1 compression which would be sweet.

If it's got flat tops or something like that You'll be up past 10:1 which isn't a good combo for pump gas.

Can you run 87 Octane now? If so You'll probably be allright. I'd do measurements once the heads are off to determine if you want to cheat and get a thicker headgasket. Bad on quench distance, but better than too high compression. a .041 Gasket will be .5 point lower compression than a stocker .015 shim gasket.

Xophertony · Posted: Fri Jun 06, 2008 9:18 am Post subject:

when you say "tony" do you mean me? did we race?

redlava · Posted: Fri Jun 06, 2008 9:48 am Post subject:

yes tony i mean you, we raced twice at PIR last summer. The engine casting number is 3970010. The previous owner had a rebuild done. The pistons are flat but they have the valve reliefs in them. I am able to run on 87 octane.

The car currently has a 2000 rpm torque converter wouldn't I want to run a larger cam then a 262? With a solid lifter cam I have heard I Have to reset the valve lash every 3000 miles?

Twilightoptics · Posted: Fri Jun 06, 2008 11:02 am Post subject:

I set my lash once the cam is settled every say.... 8000miles or before dyno/drag racing season.

262 would be good for a street car like yours on Stock even ported heads. IF you were after market heads and big intake then I'd vote bigger cam.

Xophertony · Posted: Fri Jun 06, 2008 8:25 pm Post subject:

neat. ....did i win?

i mean i know we were "dead even".. but did i win?

iansane · Posted: Fri Jun 06, 2008 8:35 pm Post subject:

Xophertony · Posted: Fri Jun 06, 2008 8:53 pm Post subject:

well in a quarter mile your never ever DEAD even.

and ian we have raced. you won. of course i have done some mods since then. and you have done some mods since then. we should race. Smile

iansane · Posted: Fri Jun 06, 2008 8:54 pm Post subject:

We raced? When? Man I've got CRS bad.

Xophertony · Posted: Fri Jun 06, 2008 9:01 pm Post subject:

after dyno 2006. we were on the way to Mikes, we lined up at a light.. we were dead even until my 700r4 shifted into 2nd, then you slowly pulled away until we hit about 60 and both let off. i think at the time you were just stealthramed. and i was all stock and missing 10* of base timing.

i think i might win now.

of course, you could STOP faster.

iansane · Posted: Fri Jun 06, 2008 9:56 pm Post subject:

Who knows. It'd be a close one. I can't remember, have you dyno'd with your current combo?

redlava · Posted: Fri Jun 06, 2008 10:14 pm Post subject:

I won but only by a few hundredths of a second.

Are the pistons I described in my last post likely to be flat tops?

Xophertony · Posted: Sat Jun 07, 2008 1:04 am Post subject:

yeah.

may have to log into tgo to view image.

torque monster. ...love my TPI

chevymad · Posted: Sat Jun 07, 2008 8:53 am Post subject:

I'm running an 010 cast 350, with flat tops/valve reliefs, ported/polished L98s, and the lunati 262 cam, though last year I ran the comp 262xe. The lunati is much stronger then the comp, but I'm having noise and rocker stud issues now. This motor is in my truck, it burns 87 octane, and feels very strong for being in a 4300# vehicle. Only dyno was done on it before this set of heads, with camel humps, and the comp cam. It also had a broken power valve which flooded the dyno room with black smoke lol. Still put 200 to the rear wheels. Its much stronger now. I think it would make a good combo. From what i've heard the 268 gives you very little more hp at the expense of alot of bottom end.

iansane · Posted: Sat Jun 07, 2008 9:39 am Post subject:

Xophertony · Posted: Sat Jun 07, 2008 10:14 am Post subject:

it might also come down to gearing. your six speed might give you the edge.

iansane · Posted: Sat Jun 07, 2008 10:50 am Post subject:

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