wrenchrookie

Little helps guys. I picked up an engine(L69,codeCLH) & tranny(HP 200R4, codeCZF) from an '87 MonteCarlo SS. I was after the tranny, but it was a package deal. I was gonna try to sell the motor, but after doing some research, the L69/200R4 combo is not a bad setup, and should do fine in a 3300lb daily driver. From what I've read, an Edlebrock Air-gap Performer, mild cam, hedders, and rebuilding the Q-jet should perk it up nicely. The stock rear was a 3.73, but I might go with a 3.42 to squeeze out an extra hwy MPG or 2.

My real question is about the heads. It comes with 181 heads(1.84/1.50, non- swirl, vortec?). I understand that they are ok as-is, but if I want to improve them, increase the intake to 1.94. I want to stay as low budget as possible, & I've seen rebuilt pre '87 L69 heads(416) w/intakes modified to 1.94 for the same price as a clean-up & 3 angle job on mine. Will they work(with the '86 intake manifold, of course)? How about 350 vortec heads (12558062, 1.94/1.50) milled .020?

I have never rebuilt an engine before, so I may be completely off, but I've done some reading. And yes, I understand if I put the same money into a 350, I'll get much better results ........but I don't have a 350.....

Atilla the Fun

First, less gear isn't gonna help the L69's mpg, due to the cam.
Second, they should be '081 heads. They are the best 305 heads ever made by GM. They do have 1.84/1.50 valves.
But if you want more, then sell the 081s on here, and get the Vortecs milled 0.030". Use the Weiand Stealth Air Strike vortec intake with those heads. And use FelPro 1094 head gaskets.
If you want more cam, you're gonna need a custom chip. But if you're willing to do that, then the Lunati 50143 is the top choice. You will need better springs, but you shouldn't need the guides machined.
This is your "maximum" realistic cam, whether you keep the 081s or go Vortec.
And if you do use this cam, considering the gearing of the 200-4R, plan on a 4.10:1 rear gear.

wrenchrookie

Thanks for the info on the heads, Atilla!

The motor is going in a '67 car, with no computer. So, I guess I will need a vacuum advance distributor. A COMP cams CCA-CL12-234-2 was suggested by the guys at Summit. What's the difference? Do you prefer the Weiand with the 081's too?

wrenchrookie

I answered my own question about the weiand on the 081's. They dont make one for that year

five7kid

iTrader: (14)

You mean like this?
http://www.summitracing.com/parts/WND-8126/

Atilla the Fun

Summit is not on my list of who I'd trust for cam suggestions. The cam they suggested would be more driveable in traffic, but that doesn't make it a good choice for either heads.
Cam is the last thing to choose, after you've finalized the heads. Do that, then I'll describe 3 choices, so you can choose among the 3.

Atilla the Fun

Not a bad choice, but from what you've typed, I'd put this on the 081s in your app: http://www.summitracing.com/parts/EDL-2604/

five7kid

iTrader: (14)

They are pretty proud of that Performer, aren't they?

Atilla the Fun

That one's basically an EPS AirGap, but it accepts the QJ, it's for '87-up iron heads, and never has any SBC intake made it easier to get at those 4 bolts nearest the carb.

wrenchrookie

As far as the 350 vortec heads go, if they are milled .030 will I maintain the 9.5/1 cr? What head gasket would you recommend? Is there anything negative about using them on my 305? I don't know if I'm going that direction, but the local machine shop wants to charge $190 per head to go though the 081's and do a 3 angle valve job. For that kind of money I'm thinking I might be able to get an upgrade.

wrenchrookie

Also, if I found a set of rebuilt 14022601's or 416's, would that work? Aren't they off of L69's too? I'm trying to look at all my options to save a few bucks and not loose any performance.

Atilla the Fun

416s aren't quite as good as 081s.

toolegit86

i have the 416's with 194's and ported they actally peform pretty well compared to the heads i had last. if it was me i would do the vortecs there just a better head to start with.

wrenchrookie

sorry Atilla, I should have read your first response again.

Atilla the Fun

it's cool. But I'm not one to ever install heads that are even slightly worse than what I already have. The advantage of '081 heads is only around 5 HP on a near-stock 305, or on a built 350, more like 10 hp, but it's 10 hp that doesn't hurt driveability or mpg or emissions.

Fast355

iTrader: (2)

The best stock 305 heads to have are 601 or 059 Vortecs. PERIOD.

Atilla the Fun

Nope. They're NO better than 081s, and they have the disadvantage of requiring the dedicated Vortec-specific intakes.

Fast355

iTrader: (2)

Go FLOW them! I promise you the 059s are better. I had stock 081s on my TPI 305 and it couldn't get out of its own way.

Its NOT hard to figure this out. The factory de-tuned L30 Vortec was rated at 230 HP/290 TQ (I can get 25 RWHP (210 RWHP) out of a PCM retune on a STOCK truck)and had a more restrictive exhaust, intake, and smaller cam than the LB9 TPI, in addition to a power robbing mechanical clutch fan.

Long story short you have NO CLUE what you are talking about when it comes to the 059s.

The 601s outflow the 081s and have a smaller, more efficient combustion chamber.

I am putting 059s on a crane 272H10 cammed 312 sunday.

Fast355

iTrader: (2)

I will further improve on my post.....This was a 195,000 mile 1998 5.0 Vortec with a tuned 0411 PCM and a modified 2002 5.0 G-Van calibration. It was upgraded to the 85mm MAF, shorty headers, cat-back exhaust, and LS1 E-Fans under PCM control. The ONLY internal engine modification is GMPP LT4(Crane Gold) 1.6:1 full roller rockers.

It pulled 225 RWHP/305 RWTQ through a tired, 195K mile 4L60E.



225 RWHP/305 RWTQ is about 300 flywheel HP and 375 ft/lbs at the crank. Running the tiny 191/196* @.050 cam. I would love to see a TPI with 081 heads hit that with its larger 202/207* duration cam.

Atilla the Fun

I have flowed them. I've also had both in my hands, at the same time. The rest of what you typed isn't even evidence to support your claim. It's inference at best. As for dyno results, not a fair comparison. Different designs of intake manifolds, different exhaust systems, and the LB9 / L98 cams had the wrong intake closing points for the rpm range.
I am TGO's last word on Vortec SBC heads for good reason. I've been obsessed with them since '96. I am not gonna tolerate you misleading people.

Fast355

iTrader: (2)

Self proclaimed genius I am not miss-leading people. YOU ARE!! 081s are hardly great heads. 195 CFM @ .500, 110 CFM exhaust, crappy open chamber that requires 36* advance for peak HP. Yea a real winner let me tell you. Introduce L30 059 head. (Stan Weiss flow chart has them at 221/163 which is more than I observed from mine on the exhaust) So 221/163, 30* advance....CLEAR WINNER...Spend $150 bucks on a good modern air-gap manifold why you are at it.

I have personally pulled more power out of 059s than I have seen produced out of a TPI based 305 running 081s. N/A. Try again....You make no mention of the fact the low cross-ram style truck manifold has all the poppets and crap right in the intake flow path. You also fail to mention the truck exhaust system with its small single catalyst is more restrictive than the TPIs Dual setup. Perhaps t he biggest oversight is the truck tunes only run 24* advance at WOT. The 081s I tested were a solid 15 CFM down on the intake side and 30 CFM on the exhaust. The lower lift flow numbers were also MUCH HIGHER than the 081s. The 059s have a spark plug that is located more centrally in the chamber than the 081. No shocker there either it uses a R43LTS style plug with a LONG REACH = more centered. What this means is when you combine it with the improved chamber and intake swirl, you get a quicker, more powerful burn. FAST BURN. I made peak power at 30* advance vs. 36-38* with the 081s. I have had both heads on the same engine untouched and the L30 heads blow the 081s out of the water.

There is no point arguing it the 059s are improved versions of the 081s.

Doom86

Fast355 where do you keep finding all these 059 heads at? I can't find any other then one's on Ebay that are reconditioned to factory specs which I obviously don't want. They were on the 96-02 305 vortecs right? It's time to start digging through the JY's looking for them I guess. They must not have made many of those 305 vortecs.

I've been looking for a set to port for when I build the low mileage TBI 305 in my 91 RS. Just looking at the photos of the runners and ports they look really awesome for factory castings. I want to try a pair out and see for my self. Have you CC'd the runners in them? If you can get 250cfm @ .500 (you got around that didn't you?) ported and have 170-175cc runners you are in surpassing Trick Flow 23 175cc on flow and efficiency. That has to be pushing a 1.94 valve to it's limits isn't it?

Atilla the Fun

Let's stick to facts.
You can't fairly compare intake manifolds, so comparing dyno results is out. That leaves the bare heads themselves.
The secret of the L31 Vortec 5700 heads, the only secret, is the short turn in the intake ports.
The Vortec 5000 heads never did get that great revision to the short turns.
I've had both styles of Vortec 5000 heads in my hands, with the valves out.
One version is swirl-port, and therefore crap. The other is absolutely exactly perfectly identical to the 081s, except for the Vortec intake manifold face.
The Vortec intake uses a taller intake port, but that wasn't the restriction on the 081s, thus it's worth nothing.
If you want to look at Vortec intakes, I've ported and polished those as well. The injection stuff being in the plenum doesn't limit ultimate flow.
With my stage 1 L31 heads on the SuperFlow 1020, I had 239 cfm. Adding the ported and polished intake in place of the clay, made no change in the flow reading. Swapping to the GMPP carbureted EGR aluminum intake dropped peak flow from 239 to 216 cfm.
You still have NO evidence that the L30 heads are better, and you cannot provide any without cheating.

wrenchrookie

I am leaning toward getting some 350 vortec heads. I may have an opportunity to pick up some rebuilt dart drt007 heads for a good price(I have to verify 1.94 valve size). Are they just as good or better than the 062's? If that doesn't work out, will 906's work well for my application.

wrenchrookie

As long as we're doing "what if"s, what if my 081 heads were modified with 1.94 intake valves? Where would that rank with the rest of them?

Fast355

iTrader: (2)

We finally got around to putting the Vortecs on the 312 in my brothers 1980 C10 last weekend. We fixed a couple of other things as well. We pulled his malfunctioning single electric fan setup off and put on a mechanical clutch fan and factory fan shroud. His Q-Jets secondary hanger has fallen apart. I took a self tapping screw of suitible size and ran it between the secondary air valve tab and the carb body, blocking them completely closed. We put the 059s on the truck with nothing more than a spring upgrade, valve job, and resurface. We used 4.100 x .016 Felpro rubber embossed shims on it. With the flat-top pistons it is around 10.3:1 compression with the 56.5cc chambers. We fixed the leaking timing cover seal as well. We used a set of R44LTS spark plugs, as opposed to the factory R45TS specification on the 305. Its the correct reach for the 059 casting and one heat range cooler. With the 272 H10 cam, GMPP Q-Jet manifold, and ~330 cfm DualJet it pulls nicely right up to 5,500 in 1st and 2nd. However, it is showing 6-7 in/hg of vacuum @ 5,500 rpm (on a mechanical gauge), 4-5 electronically. The heads flow so well compared to the earlier castings that I had to cut 1/8" off the accelerator pump plunger to give a larger pumpshot to keep it from backfiring and hesitating.

We made about 5 passes and still managed to run a 9.83 @ 69.58 with a 2.30s 60' time. We should have a good q-jet secondary cam soon to install and fix the secondaries. I fully expect to gain a good 40+ HP with properly functioning secondaries.

Here are a couple of log screen shots from the Wideband....Yes I use a wideband on a carb setup....It pulls all the way to the 6,500 rpm MSD 6A rev-limit if you let it.

Here is a WOT run on the primaries through 3rd gear and 100ish MPH.....0-100 in 16 seconds is not bad for a 4,000+ lbs truck with a 305 and the functional equivalent of a 2bbl Dual-Jet. I am not too worried about the Q-Jet though. The truck already has an EBL TBI ecm, TBI harness, TBI sensors (minus TPS) and TBI distributor controlling the timing. Some weekend soon we will put the TBI fuel system on it from the in-tank pump to the 454 TBI unit. Until then simply fixing the Q-Jet will work for us. The "TPS" value it is showing is intake manifold pressure scaled in "inches of mercury, in/hg" Barometric pressure is right at 30 in/hg. So it is pulling around 4 in/hg on this test.

Top of 1st

Top of 2nd

3rd gear right before lifting

wrenchrookie

Block is cracked ..... sucks!!!! Back to square one. The 081 heads are good though. Thanks for the advice anyway.