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I have pulled together costs of the major components of a top end "performance" build of my Buick Estate Wagons 403, those being rebuilt 350 heads, 7111 intake, QFT 670 carburetor, RV cam, timing chain. What I have not been able to count costs on however are all the incidentals, unknowns, the MAW's and TDIR's. (Might as Wells and To Do It Rights) After recently discovering one little part incidental to maintaining engine idle when the AC starts up costing over $100 I thought it may behoove me to check in with others here who have already done such a build to see what else I may need to add to my cost estimate.
For example, right now I am looking into whether I will be able to use the existing rocker covers, carb linkages, breathers etc.
I've recently sold a 38 Century in order to fund this project and will likely need to sell more parts if the costs keep building, which is fine, I'm committed to it, but I'd really rather know what the costs will be before getting into the middle of the build. Also I will be farming out the labor so don't want any hold up in time gathering more parts in that regard.
Will appreciate any help.
as an aside, here's what I swapped for the engine build.....
IMHO, I suggest doing the lower end also. Exactly what are you getting in trade for the car?
Oh I'd love to do the bottom end but funds just aren't there. I cleared around $4,200 on the '38 and have already exceeded that amount by about 500 on an estimate of just the parts I know about and shop labor. The 135k mile engine has good compression (150 + - all cylinders) burns less than 1/2 qt oil/3000 miles and aside from carb problems has been good. I briefly discussed doing the bottom with the shop and was told "that would be putting you in a whole different zipcode" so while not sure what the actual cost would be I knew by that I probably didn't want to know. Of course if they get into the engine and discover some problem I may need to get into that "zipcode" then, but keeping fingers crossed. Thanks for your opinion though, I appreciate what you're saying.
After recently discovering one little part incidental to maintaining engine idle when the AC starts up costing over $100 I thought it may behoove me to check in with others here who have already done such a build to see what else I may need to add to my cost estimate.
For example, right now I am looking into whether I will be able to use the existing rocker covers, carb linkages, breathers etc.
The rocker covers and breathers should be resuable. I suspect you will need some modification to the carb linkage to fit the new QFT 670 carburetor.
If you are spending all that on the top end, why not at least hone the cylinders and put in a new set of rings. You can also inspect the bearings. I’ve done a few this way with no problems. Just my 2 cents...
If he has nice even compression, which he does and good oil pressure, it should be fine. You should see 15 to 20 psi at idle and 45 to 50 psi hot oil pressure at cruise on a healthy bottom end.
I would put new rings in anyway, it’s cheap insurance. I’ve seen good engines develop oil consumption and start smoking within a couple of years after a top end only rebuild. Just saying....
The rocker covers and breathers should be resuable. I suspect you will need some modification to the carb linkage to fit the new QFT 670 carburetor.
Thanks.
I probably should have included air cleaner in that list. I was assuming that for the benefit of air flow I would need to go with something beside the factory type, like a 14" round chrome with paper filter? But what to do with the existing breather lines coming from the rocker covers.
Kenneth,I see you are using the quadrajet, happy with it?
If you are spending all that on the top end, why not at least hone the cylinders and put in a new set of rings. You can also inspect the bearings. I’ve done a few this way with no problems. Just my 2 cents...
Originally Posted by olds 307 and 403
If he has nice even compression, which he does and good oil pressure, it should be fine. You should see 15 to 20 psi at idle and 45 to 50 psi hot oil pressure at cruise on a healthy bottom end.
Originally Posted by Gpc1
I would put new rings in anyway, it’s cheap insurance. I’ve seen good engines develop oil consumption and start smoking within a couple of years after a top end only rebuild. Just saying....
Let me back up and be a little more specific on the compression. I've been told there's nothing to be concerned about but for sake of full disclosure
Left bank cylinders
1 - 146, 150 wet
3 – 148
5 – 148
7 – 150
Right bank
2 - 142, 150 wet
4 – 142, 150 wet
6 - 150
8 - 150
While I would love to just do the rings and bearings and walk away after this build feeling I'm good top to bottom, I also don't like spending unnecessary dollars to fix something that isn't broken. On the other hand, one concern I've had is that the increased compression in these cylinders and on the rings may cause it to "break". The shop doing the engine work for me is planning to pull the engine in order to ensure the timing cover is done right but not sure they would entertain doing new rings and bearings so it may be a mute point even if I could afford it.
Like I said new rings is cheap insurance. As for the bearings, inspect and put em back if everything looks good.
it would be good to inspect and clean the oil pump also. Chances are everything is ok by the compression numbers you’ve posted
bead hone the cylinders and put in a good quality set of rings. Talk it over with the shop. You could save $ by doing the assembly youself
if you have any experience with it or have friends. And you are correct about the new top end adding more stress to the rings.
Kenneth,I see you are using the quadrajet, happy with it?
Yes, very very happy with it. I tried a Holley 600 back in the 80s and did a LOT of tuning to get it to perform as well as the QJet. Then after all that I did a highway trip and got less highway MPG (10) than I did around town with the QJet (15), so I immediately removed the Holley and put the QJet back on and have never regretted it.
Last edited by Fun71; September 28th, 2019 at 08:08 PM.
How many miles on the motor? Does it use oil? Ever overheated?
Those compression numbers are pretty good. I'm not saying new rings wouldn't be better; but, you'll probably be ok with the current ones if it doesn't use oil and it hasn't been overheated.
Pulling the engine to make sure the front cover is done well is unnecessary and expensive unless they plan to remove the oil pan and REALLY do it correctly....if the oil pan is being pulled I'd want a couple of bearing caps removed for inspection. It can become a MAW situation in a hurry, where do ya stop?
How many miles on the motor? Does it use oil? Ever overheated?
Those compression numbers are pretty good. I'm not saying new rings wouldn't be better; but, you'll probably be ok with the current ones if it doesn't use oil and it hasn't been overheated.
Pulling the engine to make sure the front cover is done well is unnecessary and expensive unless they plan to remove the oil pan and REALLY do it correctly....if the oil pan is being pulled I'd want a couple of bearing caps removed for inspection. It can become a MAW situation in a hurry, where do ya stop?
Good luck!!!
136,000 miles, less than half a quart in 3,000 miles
They will be pulling the oil pan, I have complete confidence that it will be done right. I have receipts for everything ever done to the car by the one previous owner. In fact there have been two events of radiator boil overs leading to replacement of radiator and HEADS. When I first started driving the car, the engine temperature idiot light wasn't working. I traced the problem to a poor connection in the circuit board in the dash and strongly suspect that the light never worked since the car was new and the owner never even suspected anything until it was too late. So while I understand the damage to the heads I am interested in what your concern of prior overheating is, anything other than warped heads? And yes you are right about the MAW's, this all started with my considering a rebuild of the Quadrajet .
Last edited by MrEarl; September 28th, 2019 at 08:00 PM.
1/2 qt. oil consumption or less in 3K miles is excellent as are the compression results, both indications the rings are doing their job. My concern about overheating is that it can damage rings and/or pistons or score cylinder walls. Scoring will be seen if it exists when the heads are off, but not worn rings unless the ridge at the top of the cylinder wall is significant. By removing the engine to insure the installation of the front cover and then also doing the oil pan much of the labor toward a full rebuild is being done in the process. If it needs a bottom end rebuild later you'll end up paying twice. Honestly I'd be hesitant to pull the engine because of the front cover job unless the oil pan was leaking. If the pan is dry I'd do the front cover without pulling the motor and leave the oil pan alone.
So what to do...my $0.02 is...if the bearings look ok and the budget doesn't allow for a rebuild of the bottom end I think you'll be ok by doing the top end only. Is it the best, most perfect way? No, but it has been done many times and usually works. Sometime it doesn't work but more often it does in my experience. Be certain they look at a couple of bearings though. It's a gamble where the odds are in your favor but not guaranteed.
Throw a mechanical oil pressure gauge on the motor. Good numbers don't lie on bottom end condition. Both my last 76 350's had the oil pressure numbers I posted, 15 to 20 psi at 700 rpm in gear, 25 psi at 1000 and 45 to 50 psi all hot around 2000 rpm cruising. The bearings and crank looked near perfect on both motors. My 403 also had a fresh crank grind on the rods and similar numbers. All my overheating issues killed the crank and bearings bad. New bearings on a so so 307 crank dropped 10 psi across the range. Spinning a bunch of rod bearings dropped it 10 psi more As said, your compression numbers are very good for a motor with high 7 to 1 compression. Put an oil gauge on it to confirm the rest. Also upgrade to the neoprene rear main seal since the pan will be off. I had to actually loosen main caps to remove the rope seal on my 350.
just here to say if you wanna keep your build cheap.... attack the forums for sale section. you could save a ton of money buying the intake, carb and other componenets slightly used. I spent 4500 on a engine that would cost well over 7500 to build.
just here to say if you wanna keep your build cheap.... attack the forums for sale section. you could save a ton of money buying the intake, carb and other componenets slightly used. I spent 4500 on a engine that would cost well over 7500 to build.
I agree. I can't believe how much a even a used Performer or RPM go for these days.
Throw a mechanical oil pressure gauge on the motor. Good numbers don't lie on bottom end condition. Both my last 76 350's had the oil pressure numbers I posted, 15 to 20 psi at 700 rpm in gear, 25 psi at 1000 and 45 to 50 psi all hot around 2000 rpm cruising. The bearings and crank looked near perfect on both motors. My 403 also had a fresh crank grind on the rods and similar numbers. All my overheating issues killed the crank and bearings bad. New bearings on a so so 307 crank dropped 10 psi across the range. Spinning a bunch of rod bearings dropped it 10 psi more As said, your compression numbers are very good for a motor with high 7 to 1 compression. Put an oil gauge on it to confirm the rest. Also upgrade to the neoprene rear main seal since the pan will be off. I had to actually loosen main caps to remove the rope seal on my 350.
I'll try and get that done tomorrow. I don't currently have gauges installed but have a tach, oil pressure, volt, transmission and water temp gauges on hand to be installed after the engine work. Today I purchased a mechanical oil pressure tester and a digital timing gun with tach and will test at different RPM's starting out cold then at operating temperatures. Thank you and all for your help!!
Last edited by MrEarl; September 29th, 2019 at 07:31 PM.
just here to say if you wanna keep your build cheap.... attack the forums for sale section. you could save a ton of money buying the intake, carb and other componenets slightly used. I spent 4500 on a engine that would cost well over 7500 to build.
Originally Posted by olds 307 and 403
I agree. I can't believe how much a even a used Performer or RPM go for these days.
However I guess you get what you pay for and in my case I am using Mark aka @cutlassefi as a one stop shop and getting all the free tech knowledge and advice to go with. Just having to be patient as apparently he is a busy man and understandably so...
Yes, Mark is very good for services, knowledge and price too. I am also getting some parts to get closer to finishing my build, planning on sending money my next pay check.
48 at cold crank up and choke on idle of 1400 rpm
38 at warm choke off idle of 685
42 at 2000 hot (operating temperature)
48-50 at 3000
48-50 4000
30 at hot idle of 725
Thoughts? anything else before I unhook. I've got to go to the parts store for a new sending unit.
The 20W50 does increase it but those numbers look good. Even if you subtract 5 to 10 psi for a 10W30, still good, it means the crank and bearings are in good shape. Surprised the first number isn't around 60 psi. Mine is 60 psi at 1400 rpm, shoots to 75 psi at 2000 rpm cold with half 10W30 and half 20W50.
Last edited by olds 307 and 403; September 30th, 2019 at 09:27 AM.
the 20w50 does increase it but those numbers look good. Even if you subtract 5 to 10 psi for a 10w30, still good, it means the crank and bearings are in good shape. good to hear! I was really starting to sweat bullets. I know it would be wise to go ahead and do the rings and even bearings while the engine is out and partly torn down but this engine isn't the only thing going on in my life these days.
surprised the first number isn't around 60 psi. Mine is 60 psi at 1400 rpm, shoots to 75 psi at 2000 rpm cold with half 10w30 and half 20w50 well the car was sitting in the morning sun and ambient temperature was around 85*, don't know if that makes a big difference or not.
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Should I consider doing anything with what appears to be the original the distributor. Any upgrade that might give a payback in gas mileage or easier tuning?
Yes, re-use the original distributor but send it out a distributor rebuilder that uses an old-school Sun distributor machine to verify and modify the timing advance curve. Members on the forum know of someone who does this, I don't remember who that is. Members will also be able to tell you the best timing/advance curve to use. Without doing this you'll be leaving some ponies and torque on the table.
performance distributors builds them all new and sets them up for your set up. Price isn't that bad for an all new unit that's well made., just another option
Remember he’s towing something almost all the time. The std “performance” curve will most likely be too aggressive. I would opt for something more conservative in light of the equipment and running conditions.
I would not hesitate leave the bottom end alone. But I'd replace the rear main seal with a two piece Ford unit (you can do this by removing only the #5 main cap), clean any sludge out of the bottom of the pan, and check the timing chain.
Last edited by VinMichael; October 3rd, 2019 at 10:50 AM.
Remember he’s towing something almost all the time. The std “performance” curve will most likely be too aggressive. I would opt for something more conservative in light of the equipment and running conditions.
Right Mark I'm not wanting to build a dragster. Just get the maximum torque possible in the right acceleration range. The Wagon handles OK around town and cruising on the highway and even tows the 4500 lb Airstream ok on most long grades. It's starting off on really steep grades and maintaining the speed limit on long STEEP grades on some interstates that I am just not comfortable with it's performance and fear it may get me in trouble some day. I think you understand what I am looking for and looking forward to your recommendations.
Oh yea @cutlassefi and while getting the best gas mileage as possible also. Some challenge ehh?
Last edited by MrEarl; October 3rd, 2019 at 12:52 PM.
I would not hesitate leave the bottom end alone. But I'd replace the rear main seal with a two piece Ford unit (you can do this by removing only the #5 main cap), clean any sludge out of the bottom of the pan, and check the timing chain.
Thanks, relieved to hear your and others comments to that affect. I've discussed new gaskets and the rear main seal with the shop and they plan to use the Ford unit as you mentioned. Timing chain replacement is in the plans
Yes, re-use the original distributor but send it out a distributor rebuilder that uses an old-school Sun distributor machine to verify and modify the timing advance curve. Members on the forum know of someone who does this, I don't remember who that is. Members will also be able to tell you the best timing/advance curve to use. Without doing this you'll be leaving some ponies and torque on the table.
Good luck!!!
Originally Posted by olds 307 and 403
Everyday Performance does recurve distributors, pretty sure he has Sun distributor machine.
Originally Posted by coppercutlass
performance distributors builds them all new and sets them up for your set up. Price isn't that bad for an all new unit that's well made., just another option
September 26th, 2019, 02:08 PM
Thanks for your opinion though, I appreciate what you're saying.
