Top End Rebuild - Page 4 - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


1987-1991 Parley with regards to your 1987 to 1991 Bonneville, Olds 88 or Buick Le Sabre Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

Reply
 
 
 
Thread Tools Search this Thread
Old 12-26-2004, 01:45 PM   #31
Senior Member
True Car Nut
Thread Starter
 
Join Date: Apr 2004
Location: Three Oaks, Michigan
Posts: 4,879
Thanks: 0
Thanked 0 Times in 0 Posts
opensourceguy is on a distinguished road
Default

I am returning with some updates.

All the engine parts are sitting in my basement [moved from trunk and garage]. I talked to Straitor, and he recommended using a grinding stone to port the heads.. so I picked up a few varieties of them at Sears. I will probably start the porting sometime this week. Is there anything I should be prepared for, or be caustious of?

I also talked to Straitor about decking the heads.. he said it wouldn't be possible, since there isn't a lot of clearance as-is. I just want a second opinion. I have zero clearance from the piston to the top of the block, and the heads don't have much more than 6mm from gasket mating surface, to the intake valve. I was thinking of decking the heads, to get a 9:1 compression ratio.


-justin
opensourceguy is offline   Reply With Quote
Old 12-26-2004, 01:54 PM   #32
Senior Member
True Car Nut
 
Join Date: Nov 2002
Location: Texarkana, Texas
Posts: 6,041
Thanks: 0
Thanked 0 Times in 0 Posts
Damemorder is on a distinguished road
Default

Try not to port very far, don't get aggresive with it. If you hit a coolant channel you're hosed. Just go slow use light pressure and be cautious.

You're too tight to go too far, but definatly get them checked true.
Damemorder is offline   Reply With Quote
Old 12-26-2004, 02:22 PM   #33
Senior Member
True Car Nut
Thread Starter
 
Join Date: Apr 2004
Location: Three Oaks, Michigan
Posts: 4,879
Thanks: 0
Thanked 0 Times in 0 Posts
opensourceguy is on a distinguished road
Default

My coolant ports are nowhere near the intake ports. At least.. I don't think so. Wait.. the inlet for the coolant isn't near the inlet for the intake.. does that mean that the coolant ports run throughout the head.. and the intake ports may hit them? Ah ****, I never thought of that. How can I tell if I am getting close? I am only going to gasket match, which is 2-3mm of surface area. I was also thinking of cleaning up the exhaust ports.. since they have quite a bit of carbon build up. Should I just clean them up, or port them a little too? I don't think there is a whole lot of material I can take off of the header.. and I don't have any header gaskets, so I can't just gasket match. I'm thinking to just leave it alone, and just clean up the carbon.


-justin
opensourceguy is offline   Reply With Quote
Old 12-26-2004, 03:43 PM   #34
Senior Member
True Car Nut
 
Join Date: Jul 2003
Location: Toronto, Ontario, Canada
Posts: 5,158
Thanks: 0
Thanked 0 Times in 0 Posts
repinS is on a distinguished road
Default

Standard machining of the head will raise your compression by a quarter point, tops, apparently, but I dug up something from elsewhere that might bring a little insight:

Quote:
Originally Posted by ToyotaCressida.com Forums
If the machine shop requires a lot of milling, you might have to go with a metal gasket, simply to make up for the bigger gap between head & block. My 7M'* head was shaved 0.4mm and I ended up putting in a 1.4mm metal head gasket, this gave me a compression ratio of 10:1. Ideal hg thickness is about 1.2mm stock. so whatever gets removed should be made up for as long as you don't go past 1.0mm minimum thickness. On hot days I have to run 92 or 94 octane to prevent pinging.
... so doing the math, 0.2mm off in total bumped compression up from the stock 9.2:1 to 10.0:1, not sure if this 10.0 number is accurate at all, but it'* something to think about.
repinS is offline   Reply With Quote
Old 12-26-2004, 04:01 PM   #35
Senior Member
True Car Nut
 
Join Date: Jul 2003
Location: Toronto, Ontario, Canada
Posts: 5,158
Thanks: 0
Thanked 0 Times in 0 Posts
repinS is on a distinguished road
Default

Head, Before
Head, After

They're hemi chambers, IIRC. This motor traces its lineage back to 1965, and even the original motor was the same way, albeit with a 2-valve head.

... It cost the guy (same guy who I quoted above) about $60 CDN to do this, and the job was rounded out with a metal head gasket and ARP bolts.

Might I add, he ported the head, as well.

Quote:
Ok, here'* my ports..




A little minor cleanup, I don't expect to see much of any result, but it'* nice to know it'* clean and smooth in there. I used a metal grinding bit in a dremel with an extention.

I cleaned and polished all the valves yesterday. 24 valves takes a long friggin time!! now I'm going out to assemble. @$#% 24 valve retainers!!!




His car (in Ottawa, Ontario) is holding up great, too. Advanced timing (these motors have distributors), 16" wheels, new paint (he did it himself, awesome job) everything. A prime example of a proper head job.
repinS is offline   Reply With Quote
Old 12-26-2004, 04:18 PM   #36
Senior Member
True Car Nut
 
Join Date: Jul 2003
Location: Toronto, Ontario, Canada
Posts: 5,158
Thanks: 0
Thanked 0 Times in 0 Posts
repinS is on a distinguished road
Default

It'* a 3.0L motor (190hp/185tq, iron block/aluminum head, Toyota'* 7M-GE, 7M-GTE if turbo), head-gaskets deluxe due to too low torque spec from the factory. A proper HG job (not necessarily metal gaskets) will ensure that the head gasket will never come a-knockin' for the life of the car It was around from '86.5 to 1992, so about the same era as the Vin C 3800.

Piston tops
You be the judge on these pistons, Jr... this pic is the same motor, different car.
repinS is offline   Reply With Quote
Old 12-26-2004, 07:04 PM   #37
Senior Member
True Car Nut
Thread Starter
 
Join Date: Apr 2004
Location: Three Oaks, Michigan
Posts: 4,879
Thanks: 0
Thanked 0 Times in 0 Posts
opensourceguy is on a distinguished road
Default

I am thinking someone was hinting for some pics? Well, it'* your lucky day.

My rear Cylinder Head.. and some rockers


The bottom of my rear Cylinder Head --the head gasket came off very clean.. is that normal? I could just peel it off clean, right from the head.. but I am keeping it on, so I don't have to be so careful when laying it down, or whatever..


Another pic of the bottom of my rear Cylinder Head


A close up of the dome


An off center close up of the dome --notice how flat it is


A spot on my front Cylinder Head.. it seems to have black paint with some rust underneath.. anyone think I should sand down the rust, and repaint? It'* just surface rust.. but I am going to be painting so much stuff already.. it wouldn't hurt to mask off this thing and give it a shot of black.


My rusty Spark Plugs


A litte one for Straitor.. check your Yahoo offline IMs


It'* too damn cold for me to go out to the car.. it is supposed to warm up this week, so if it does, I will get some pics of some stuff in the car.


-justin
opensourceguy is offline   Reply With Quote
Old 12-26-2004, 07:37 PM   #38
Senior Member
True Car Nut
 
Join Date: Nov 2002
Location: Texarkana, Texas
Posts: 6,041
Thanks: 0
Thanked 0 Times in 0 Posts
Damemorder is on a distinguished road
Default

I went and grabbed my vin L head, they look exactly alike... Justin, did you have a bar under the rocker pedastals with the part # 24501397on it? I wonder if 93 rollers would fit on your 89 head.....

Pic #1, looks exactly the same, rockers are same but pedastal differs.
Pic #3, see those cast on numbers? Justin has 185, 14, 13... I have 136, 14, 8...

Justin , there'* numbers between the rockers, what are yours? I have M172 and 2138..
Damemorder is offline   Reply With Quote
Old 12-26-2004, 08:31 PM   #39
Senior Member
True Car Nut
Thread Starter
 
Join Date: Apr 2004
Location: Three Oaks, Michigan
Posts: 4,879
Thanks: 0
Thanked 0 Times in 0 Posts
opensourceguy is on a distinguished road
Default

If the rear head were installed.. it would be on ther driver'* side. it has 3485. In the center, there is some sort of sun dial type thing.. and if it were installed, it would be pointing towards the firewall. Then on the passenger'* side I have something that looks like H033. The pics suck, and so do my lighting.. so it'* hard to tell.


-justin
opensourceguy is offline   Reply With Quote
Old 12-26-2004, 08:56 PM   #40
Senior Member
True Car Nut
Thread Starter
 
Join Date: Apr 2004
Location: Three Oaks, Michigan
Posts: 4,879
Thanks: 0
Thanked 0 Times in 0 Posts
opensourceguy is on a distinguished road
Default

*dances*

Straitor and I have come to the conclution.. that '93 rockers will fit on my heads. We have made a deal, and I bought some from him. I just couldn't wait to tell everyone . Also, after looking at my rockers for quite some time measuring, I noticed that my rockers were very worn where it rides on the spring. It'* too small to measure, but it'* almost worn flat [and the rocker isn't flat in that spot]. It seems a little much wear.. don't you think?


-justin
opensourceguy is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
99gpgt top end rebuild danneybo Pontiac 9 10-30-2012 01:58 AM
Top End Rebuild * NEW Q's * last post statusplease 1992-1999 18 04-11-2008 12:37 AM
Which do you prefer? Low end power or top end? Bonneville92V688 General GM Chat 43 10-31-2007 06:05 PM
Front end rebuild question PLANT PROTECTION 1987-1991 3 01-19-2006 06:22 PM
Top end rebuild help Hurianek 1987-1991 25 08-19-2004 03:14 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 05:32 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.