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Discussion Starter · #1 ·
code guru please , 705175 YS is on the pass front of the engine, I was told its a ram air 400 from a 60's gto with an auto trans, I see the ys is gto trying to narrow down closer

Engine has oval port heads best I can tell and a 4 bbl q jet
 

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I have an engine a co worker gave me 20 years ago 705175 YS
The numbers are just a serial number, and mean very little. The YS was used several years on different engines.

Looks like the YS code was used on 350's, 389's and 400's, beginning in 1965, thru 1978..

http://www.wallaceracing.com/enginesearch4.htm

You'll have to get the block casting number, off the pad just below the rear of the passenger side head, and the 4 digit date code, from near the dist hole, to make a positive ID. :yes
 

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code guru please , 705175 YS is on the pass front of the engine, I was told its a ram air 400 from a 60's gto with an auto trans, I see the ys is gto trying to narrow down closer

Engine has oval port heads best I can tell and a 4 bbl q jet
http://www.firebirdnation.com/forums/topic/6846-how-to-id-a-pontiac-engine/?p=1340961

I think all 400 engines came with either a 2 barrel or a Q-jet. But, the intake and carb could have come off another engine. The easiest way to make a positive ID is by using the YS code, along with the block casting number and date code. :yes

According to the Wallace site, all YS code blocks came with a 4-barrel carb. The '67, '68, & '69 400 engines would have had a Q-jet. But all three would have had D-port heads. They list 670 for '67, 16 for '68, and 62 for '69. Don't know about the RA part, but it may have indeed came in a GTO.

What are the numbers on the heads and intake manifold.?
 

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Some help with narrowing down and engine I have passenger front of block says 705175 Y S

Supposed to be GTO 60's auto trans, has factory 4 bbl q jet and oval port heads
Plug the YS into the engine code block in this Wallace engine ID finder. Then click on the SUBMIT block at the bottom.

http://www.wallaceracing.com/enginesearch4.htm

As you can see, the YS code was used in several years, on 350, 389, & 400 blocks. As mentioned in the other thread, to make a positive ID on the block, you'll need to get the block casting number and date code. The casting number is located on a pad, just below the rear of the passenger side head. The date code consists of 4 digits, and is located just behind and towards the driver side of the distributor hole.

The 1st digit of the date code is a letter, which indicates the month of the year--A=Jan, B=Feb, C=Mar, D=Apr, E=May, etc. The next 2 digits indicate the day of the month--03=3rd day, 31= 31st day, etc. The last digit is also the last digit of the year the block was cast. 8=1968, 9=1969, 0=1970.

If the date code indicates that the block was cast in the last half of the year, then many times, it was used in the following model year car.

If there is a better way to make a positive ID on a block, I'm not aware of it. But, even after you ID the block, that doesn't mean that the heads, intake, and carb came on that block. :no All 3 pieces could have come off different engines. OR, 1 or more of these may have indeed come on the block. So, you need to also check the numbers and date codes of these parts, to ID each part. Then, and only then, will you have a good idea of what you have. :yes
 

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Discussion Starter · #6 ·
I see you needed numbers by the dist hole, next time I go to dads I will look , been sitting on that crate for like 20 years and it was assembled when I got it
 

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Looks like the block and intake could both have been used in either a '68 or '69 model. The best I can tell from the pic, the Q-jet looks to be a side inlet Chevy model--possibly '76 or later, since it has the APT plug in front of the vent, down where the air cleaner gasket sits. :smile22:
 

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"...Did I get the correct cast # for the head?..."

Nope--that's the date code--the date on which it was cast. The ID number you need will probably be just 2 digits. They will be over the center exhaust ports. If they are off a '68 or '69 GTO, they will probably be either number 16 or 62. But, the original heads could have been replaced with something else. The E208 head could have been cast May 20, 1968, which is most likely. But, it could be one of several heads which were cast in '68, such as 14,15,16,17,18, 31,62,96, 215, 216. The #96 heads are round port--the rest are D-port.

But, it could also be a 6x head which was cast May 20, 1978. These were used on '78 and '79 400 engines. The heads may be so rusty that you can't make out the head #. There are still ways to narrow down the ID on 'em. :yes
 

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Discussion Starter · #12 ·
OK rear of block by the dist hole looks like E038

Big cast numbers on head looks like 16

Also I don't think that's the Carb that came with the engine as I have several on the shelf next to it, if I had to guess it was one of these
 

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Discussion Starter · #13 ·
I am going to eventually build this engine for my 67 so knowing where to spend money is what I am looking for

Like if the cylinders are good should I still punch it .030 or just change piston type, should I port these heads or look for a different type?

Cam will be mild nothing crazy and probly just Hydraulic lifters no roller setup

In the end I just want a nice street car that has power if I want to step into it
 

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Any of those Q's with the slashed vent tube should be good, if they are rebuildable. :yes

That's what we used on all our race cars. I can make out the number of one of those. It's #7040262. That's off a 1970 model big Pontiac, with a 455 and auto trans, according to the Wallace site. It's definitely worth the price of a good rebuild, if it's in good enuff shape to be rebuilt. :yes

http://www.wallaceracing.com/enginesearch4.htm.

I see no reason not to go .030 over, just to be sure the cylinders are round, and the same size, from top to bottom.

"...should I port these heads or look for a different type?..."

The #16 heads are good. But they don't need any porting, unless you plan to do some serious racing. If around 350hp is not enuff, I'd put a stroker assembly in the block. That way, you'll have 455 or more cubes, at least 400hp and about 500ft lbs of torque. Again, no porting needed. Your $$ can be better spent on something else. I never ran any ported heads, and ran on down into the upper 11's. :smile22:
 

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Discussion Starter · #15 ·
OK so this is a 68 gto engine and a good engine to go say .030 with a mild cam and heads should be good as is ( with valve job) no porting or oversize valves needed

Probly throw my edelbrock intake and Carb on top and I already have headers plus the ex manifolds off this engine
 

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Well, the rebuild all depends on the size of your budget. 1 thing you definitely need is forged pistons. MOST cast replacement 400 pistons are the dreaded "8-eyebrow pistons". They are notorious for causing detonation. :yes

The cheapest forged pistons are the Sealed Power/Speed-Pro #L2262F pistons. You can usually buy 'em for a little over $300 from an Ebay store, and less than $400, with moly rings.

http://www.ebay.com/itm/Speed-Pro-TRW-Pontiac-400-Forged-Coated-Skirt-Flat-Top-4VR-Pistons-Set-8-030-/190855076806?hash=item2c6fd95bc6:g:GesAAOxyB0VRuHEA&vxp=mtr

http://www.ebay.com/itm/Speed-Pro-TRW-Pontiac-400-Forged-Coated-Skirt-Flat-Top-Pistons-MOLY-Rings-30-/190855081106?hash=item2c6fd96c92:g:H-0AAMXQDK1RuHYs&vxp=mtr

It is also recommended that you not go back with the cast rods, but rather with at least the RPM brand 5140 forged rods. They're $288 shipped.

http://www.racingpartsmaximum.com/sae5140stockrod-2.html

There have also been lots of failures of those old valves, causing major engine damage. :( Those heads already have the big 2.11/1.77 valves, but should be upgraded to one piece stainless valves, like the Ferrea 5000 series.

http://www.ebay.com/itm/Ferrea-Stainless-Valves-Pontiac-350-400-428-455-Set-Intake-Exhaust-1-770-2-110-/231835448673?_trksid=p2141725.m3641.l6368

Other than that, you need a GOOD valve job, including bronze guides, good seals, etc, done by somebody with experience doing Pontiac heads. Most also choose to switch over to 7/16 BBC type rocker arm studs. But it is not necessary, with a mild cam. :smile22:
 

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Yeah, I've been recommending 9.5 max CR for a while. But, it seems that lately, every time I do. several guys will come back telling about how they have been running 10:1 CR for years, with absolutely no problems at all.

I ran some numbers thru the Wallace CR calculator and came up with 10.03 CR.

400 + .030, 75cc heads, 6.7cc valve reliefs, .039 x 4.3 Fel-Pro head gaskets, .005 deck height CR = 10.03

http://www.wallaceracing.com/cr_test2.php

A couple of ways to decrease CR slightly, is to smooth off all the sharp edges of the piston valve reliefs, and remove some material from the combustion chambers. The chambers should be measured, before you build. They may be either more or less than 75cc.

Most say that as long as you run a cam with a lot of advertised duration, rather than one of the steep ramp cams, like the CC XE series or the Lunati Voodoo series, detonation is not a problem. So, an 068 clone, like the Melling SPC-7, or a Summit 2801 cam should work OK with premium pump gas.

Of course, you'll need to have your timing curve set correctly, and not run your total or vac advance too high. And you need the carb tuned correctly, and not too lean. Also need to run good quality 91-93 octane gas. The best in my area is said to be the Shell brand.

http://www.autoblog.com/2015/06/05/shell-super-premium-gasoline/

Of course, the safest way would be to either run dish pistons, or mix in a little racing gas, or switch to E-85. But, that's another discussion, altogether. :smile22:
 

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Discussion Starter · #19 ·
Wow tons of info thanks, I think the engines gonna be a while, I am just happy I have a good starting point

I had a 400 years ago paid for everything and the machine shop went out of business, lost several thousand and the engine, I was pissed for a long time
 

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Wow tons of info thanks, I think the engines gonna be a while, I am just happy I have a good starting point
Yup Don is good on the info,lots of working knowledge
 
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