80smetalfan

I'm livening up a 350 in a shallow-geared daily driver. Another 010 block. I'm picking up some resurfaced/rebuilt 305 heads for $40 from a friend, as long they're not swirlports or a similarly bad casting. I basically want to make absolute craploads of torque with little regard for any power above 5000 RPMs and if possible, decent gas mileage. I'm using a stock quadrajet along with stock exhaust manifolds, with exhaust being about 3 feet of true duals into dual 18 inch glasspacks, with no cats. The drivetrain is a 700-R4 with 2.14 rear axle gears.

Here's my line of thinking so far:

305 heads will not only give me some good high compression, but the small 305 valves should yeild some good torque as well. Not sure what the 010's had in terms of stock internals, and I'm not sure if flat top pistons would put me out of the range of pump gas.

A Comp cams XE-250H

An Edelbrock Performer intake



The motor has 1985 truck smogger heads/cam/intake with all emissions and AC removed, and it's in a g-body with a 700-r4 (that I put in to replace a TH-200). With the stock smogger heads/cam/intake and nice cap/rotor/wires, it's actually already pulling mid to low 15s, even with the terrible axle gears.

I want some recommendations on a cam with craploads of torque and good pull to at least 4500 RPMs, maybe even to 5000. If there's something similarly affordable that will outperform the CC XE-250H with those gears, I'd be interested in it.

I'm not real sure about intake. I've considered maybe an Edelbrock Torquer II, but Edelbrock doesn't have a whole lot about it on their site, and I haven't seen much feedback on here about it.

Just looking for suggestions. I'll likely do the build with the XE-250H and Performer, but I'm open to any suggestions.

Thanks!

thirdgen88

TPI..

RB83L69

With typical flat-tops you will be at about 10½:1 CR... WAY out of the range of the possible with that sort of a cam. If that's what you've got, I would suggest not building this, and start looking for some other parts instead.

If the pistons have a 15cc dish, you'd end up at around 9½:1; which is about as high as you could go with a cam that will make THAT MUCH cyl pressure at low RPMs.

Changing the induction system won't change this basic mismatch.

The T2 would be one of the absolute worst possible intake choices..... for this, or just about anything else. The Performer would be the way to go for the purpose at hand.

80smetalfan

Yeah, I know. The car itself is an extreme budget project, and I don't have the $$$ to go FI yet. I've spent a total of $500 on the car (including the price of the car and parts for the swap) and it's already faster than my 91 RS was stock. Whenever I end up blowing up this setup, I'm probably going to go with a TPI setup and bore/stroke it to a 383 for a little more torque .

80smetalfan

I see. I had figured I'd be up a creek if it's got flat tops. I might just either get the current smogger 350 heads milled (they're 76 CC chambered) and rebuilt, along with maybe self-porting them, or just pick up some L98ers. Or I guess I could just buy some new dished pistons.

Fast355

iTrader: (2)

Perfect use for ported 193 swirl ports!!!!

80smetalfan

I'm thinking these heads just won't work unless they're older 8.6-1 LG4 heads. I've had people tell me that using the dished pistons with them will kill my quench.

Would using .051" or similarly thick headgaskets make up enough extra cc's to help me out with compression?

JesasaurusRex

iTrader: (3)

2.14 gears???

RB83L69

I did my CR calculations with a .039" head gasket. The 2 numbers I gave, were for a 9cc chamber volume difference.

8.6:1 LG4 heads are 58cc, same as L69 or LB9 heads. The lower compression in the early LG4s came from dished pistons.

If you can find a head gasket that holds 9cc more in its bore than a .039" one, then it will get you where you need to be. That's about .080". Somehow I think this could be a low probability.

Sounds to me like you simply have the wrong ingredients for what you want to build. You either need to build something else with them, or replace them with what you need for what you want to do.

Nate86

Yeah, I noticed this too. What's up with that? Third gens never came with anything higher than 2.73s, I thought.

rx7speed

if your worried about quench a thicker headgasket would kill your quench more then getting the correct style dished pistons

there are some pistons made with a reverse dome or d shape dish whatever you want to call it that still has a quench pad in there just the dish part is in the shape of a d that fits the same shape as the depression in your combustion chamber.

this way you cna still keep your quench which gives many bennies and get to lower your compression to a better level

84L69TA

If you read his first post....he said all of this was going into a G-body, which was offered with 2.14 gears. He said nothing about putting this into a third-gen.

Fast355

iTrader: (2)

My caddy had 2.53s and a 2004r.

80smetalfan

Yeah, I'm still just tossing ideas around as far as the heads right now. It's not a huge deal if these heads won't work, I'll find some 64 CC 350 heads if these ones are totally not feasible for this project, no big deal. The main reason I'm so inquisitive about the heads is that a good friend is selling them to me for only $40, and they're in really good shape. They were totally rebuilt and magnafluxed last month, so nothing is wrong with them. He had an 84 Z that he was putting them on, but he picked up a BBC for cheap that he's putting into it instead, so he has no use for them.

I did find out these heads came off of a 80s El Camino 305. They've been coated in something on the valve cover side, and the casting numbers are indistinguishable. It's not the obvious (oil), because these things have been totally rebuilt/resurfaced/cleaned, and look brand new. Don't know if the fact that they're not F-body heads will affect anything about them. Anyone know if these are just LG4's as well?

RB83L69

Probably; which would be the same as 86-back L69 or LB9 heads. All of those motors used the same heads. Don't get hung up on the "LG4" deal.

But non of that matters; they're not going to work for this, no matter which motor they originally came off of.

64cc is probably still too much CR. You need to be at 9 or so. You'll be at 9.7 with 64cc and .039" gasket and a normalish deck height with the piston in the hole .025".

Same conclusion as above.

84L69TA

RB83L69: Wouldnt that be 87 and earlier? The reason I ask is because I thought the 87 LG4's used the centerbolt "LB9" heads, and then the swirlport L03 heads were introduced in 1988. So arent the 416 heads the same as the 87 centerbolt heads, except for valve cover mounting and the center 2 intake bolts?

WhiteLightnin83

if ur lookin for around 9.0:1 with that setup you can probley go with 70cc chambers which is about 8.89:1 i believe, or if you wanna go a bit over go with 67cc's and its about 9.2:1... all providing i did my calculations correctly that is

SSC

Crower makes a tq cam "Baja Beast" it's supposed to be the best low end cam made. Ive never used it since ive been told it's spent at 4500 rpm but that would be perfect for what you want.

I'd suggest you do use the fresh 305 heads and just used some reverse dome pistons AKA dished so you can run a fair amount of advance. If you were to use the Baja B, RD Pistons and those small valve heads it would make a good torque engine. It shouldent be too hard on gas either.