Tips and pointers for 403 "build" with #6 heads needed
#42
Thanks Ralph, that was a very good explanation of the reading method of the scale. It's not a problem for me to borrow a more accurate digital caliper, or even a micrometer, so I'll do that before buying bearings.
Thanks everyone for "bearing" (haha, pun intended :-D) with me, this is my first time doing this, I'm just a carpenter... I may ask stupid questions, but I'm a fast learner, and I do have a little more than just saw dust for brains
Thanks everyone for "bearing" (haha, pun intended :-D) with me, this is my first time doing this, I'm just a carpenter... I may ask stupid questions, but I'm a fast learner, and I do have a little more than just saw dust for brains
#43
That caliper is actually an old one inherited from my dad, but it has rarely been used. Old = not Chinese made. My dad was a brick layer, and yes, I hold pride in my trade, but I find it satisfying to learn stuff!
#44
Thats very true, that it removes alot of confusion when the caliper converts the number with a press of button, no chance for convert error, atleast error by human.
.002" is roughly .05mm, actually its not .002", its something like .0019xxx" but .002" will do
Hmm.. Your two cents would be either 0.19 öres ( currency at Sweden is Krone, SEK) or 0.02 cents ( at Finland, we use Euro, €)
.002" is roughly .05mm, actually its not .002", its something like .0019xxx" but .002" will do
Hmm.. Your two cents would be either 0.19 öres ( currency at Sweden is Krone, SEK) or 0.02 cents ( at Finland, we use Euro, €)
HAHAHAHAHA, I love the humor. Now you know what my opinion is worth in your currency.
I have "several" older British motorcycles. They are "inch", the newer stuff is metric. The engine displacement is in c.c. and piston sizes are always in mm. Throw in the Litre's I convert stuff. Then trying to convert "American" currency to Euro's made me dizzy. Now Britain is probably going to use "Pounds" again, another dizzying conversion.
#46
Thanks Olds 307 and 403!
Received word tonight that my heads where finished! Haven't spoken to the machine guy myself, I'll update here when I have picked up the heads, and post pictures.
I picked up the Comp Cams Magnum steel roller tip rockers this Friday, I paid $107,50 for them, including the guide plates, studs and Polylocks, but no pushrods, since those were for BBO.
Question: is it possible to hone the cylinders for new piston rings without taking out the crank? I don't know why, but putting in new rings kinda scares me? I am trying to be less scared nowadays, I had a heart attack for 4 months ago, at 44 years old, and I need to tell myself to live more. Life is short...
So peptalk on the re-ring is welcomed. Or someone telling me it's not necessary
Received word tonight that my heads where finished! Haven't spoken to the machine guy myself, I'll update here when I have picked up the heads, and post pictures.
I picked up the Comp Cams Magnum steel roller tip rockers this Friday, I paid $107,50 for them, including the guide plates, studs and Polylocks, but no pushrods, since those were for BBO.
Question: is it possible to hone the cylinders for new piston rings without taking out the crank? I don't know why, but putting in new rings kinda scares me? I am trying to be less scared nowadays, I had a heart attack for 4 months ago, at 44 years old, and I need to tell myself to live more. Life is short...
So peptalk on the re-ring is welcomed. Or someone telling me it's not necessary
#47
Thanks Olds 307 and 403!
Received word tonight that my heads where finished! Haven't spoken to the machine guy myself, I'll update here when I have picked up the heads, and post pictures.
I picked up the Comp Cams Magnum steel roller tip rockers this Friday, I paid $107,50 for them, including the guide plates, studs and Polylocks, but no pushrods, since those were for BBO.
Olds 307 and 403 may have some wisdom on those poly locks and studs. Seems like some brand didn't stay adjusted.
Question: is it possible to hone the cylinders for new piston rings without taking out the crank? I don't know why, but putting in new rings kinda scares me?
Simple answer.......yes. Would I do it ? NOOOOOOOOO
I am trying to be less scared nowadays, I had a heart attack for 4 months ago, at 44 years old, and I need to tell myself to live more. Life is short...
So peptalk on the re-ring is welcomed. Or someone telling me it's not necessary
Received word tonight that my heads where finished! Haven't spoken to the machine guy myself, I'll update here when I have picked up the heads, and post pictures.
I picked up the Comp Cams Magnum steel roller tip rockers this Friday, I paid $107,50 for them, including the guide plates, studs and Polylocks, but no pushrods, since those were for BBO.
Olds 307 and 403 may have some wisdom on those poly locks and studs. Seems like some brand didn't stay adjusted.
Question: is it possible to hone the cylinders for new piston rings without taking out the crank? I don't know why, but putting in new rings kinda scares me?
Simple answer.......yes. Would I do it ? NOOOOOOOOO
I am trying to be less scared nowadays, I had a heart attack for 4 months ago, at 44 years old, and I need to tell myself to live more. Life is short...
So peptalk on the re-ring is welcomed. Or someone telling me it's not necessary
I would prefer (2) for engine cylinder honing to break the "glaze" and making a "cross hatch".
Others may have other suggestions.
.......Just my two cents worth (.1860 Krona)
#48
The Polylocks looks like they are Pioneer brand. Unfortunately, the guy I bought the set off couldn't find one of the locks, so he kept one and was going to have his work make a copy of it, but I stopped by my parts place on my way home, and was able to get 2 new ones, these were Mr. Gaskets. Hope that works.
Yes, I saw that bottle brush type on Engine Masters on YouTube a couple of days ago, and the three stone type I have used on an old snowmobile I had decades ago.
Yes, I saw that bottle brush type on Engine Masters on YouTube a couple of days ago, and the three stone type I have used on an old snowmobile I had decades ago.
#49
Question:
Is it worth the extra cost to get Clevite bearings instead of Sealed Power?
Remember that I'm in Sweden, so cost of parts are almost twice compared with USA. Main bearing set is $182 for Clevite, and $129 for Sealed Power. Rod bearing set is $107,50 for Clevite and $86 for Sealed Power.
Is it worth the extra cost to get Clevite bearings instead of Sealed Power?
Remember that I'm in Sweden, so cost of parts are almost twice compared with USA. Main bearing set is $182 for Clevite, and $129 for Sealed Power. Rod bearing set is $107,50 for Clevite and $86 for Sealed Power.
#51
Go with the sealed power bearings, they will be fine. You can leave the rings if you don't want to pull the crank. The compression was good correct? As for the Poly locks, hold with a wrench and make sure you use an Allen head socket and tighten them with a long ratchet, good and tight. Make sure you get an adjustable push rod to get the best geometry possible. I am doing that rather than just reordering the 8.5" pushrods that came with the heads when I do the 403 stroker this winter.
#52
Go with the sealed power bearings, they will be fine. You can leave the rings if you don't want to pull the crank. The compression was good correct?
Yes, at least I had good compression when I installed the cam. It doesn't use any oil at all.
As for the Poly locks, hold with a wrench and make sure you use an Allen head socket and tighten them with a long ratchet, good and tight. Yes Sir!
Make sure you get an adjustable push rod to get the best geometry possible. I will borrow an adjustable pushrod from the machine guy, will buy correct length this time!
I am doing that rather than just reordering the 8.5" pushrods that came with the heads when I do the 403 stroker this winter.
Yes, at least I had good compression when I installed the cam. It doesn't use any oil at all.
As for the Poly locks, hold with a wrench and make sure you use an Allen head socket and tighten them with a long ratchet, good and tight. Yes Sir!
Make sure you get an adjustable push rod to get the best geometry possible. I will borrow an adjustable pushrod from the machine guy, will buy correct length this time!
I am doing that rather than just reordering the 8.5" pushrods that came with the heads when I do the 403 stroker this winter.
#53
Spoke to the machine guy, and he said that he milled the heads .055, so the chamber size measured to 61 cc now. They were 68 cc from the start. Do you think that will give me trouble with the intake manifold, fitting the bolts?
I tried to enter the numbers into a compression calculator, look at the picture and tell me if I am in the ball park with the numbers?
Anyone want to guess what this combination will give in hp/tq? (I want to talk about more fun stuff now, even if it is speculation!)
I tried to enter the numbers into a compression calculator, look at the picture and tell me if I am in the ball park with the numbers?
Anyone want to guess what this combination will give in hp/tq? (I want to talk about more fun stuff now, even if it is speculation!)
#55
Working on assembling the 403. I have put in new Clevite bearings after a gentle polish of the journals with 400 and 800 grit wet (with oil) sanding paper. Bolted on the #6 heads and measured the pushrods, which came to 8.300". Put in the new oil pump, washed the oil pan and put it on with new rubber seals and the cork gasket. Did a test fit with the Edelbrock Performer intake, which went well, so for future reference, you can at least shave the heads .055 if you are using the Fel-Pro head gaskets and the "turkey tray" type intake gasket tray.
Also, for future reference on the DOWEL PIN holes of the 350 heads vs the dowel pins on the 403 block. I couldn't find a true serious reference on which dowel pin holes was needed to address, so here it is: the 403 block has 2 dowel pins on each cylinder bank, sized 5/16". The 350 heads has 3 dowel pin holes on each head, one hole is by itself on one end of the head, on the other side (end), the pin holes are in a pair, spaced apart by maybe 3 - 4", the inner hole (toward the middle of the head) does not need to be addressed. The outer hole is smaller, maybe 3/16",and needs to be drilled to 5/16. I have attached a picture of a head and put an X on the pin hole that needs enlarged, and circled the rest of the pin holes.
Also attached is a picture of the engine with the progress so far. I will be cleaning the engine and paint it soon.
Also, for future reference on the DOWEL PIN holes of the 350 heads vs the dowel pins on the 403 block. I couldn't find a true serious reference on which dowel pin holes was needed to address, so here it is: the 403 block has 2 dowel pins on each cylinder bank, sized 5/16". The 350 heads has 3 dowel pin holes on each head, one hole is by itself on one end of the head, on the other side (end), the pin holes are in a pair, spaced apart by maybe 3 - 4", the inner hole (toward the middle of the head) does not need to be addressed. The outer hole is smaller, maybe 3/16",and needs to be drilled to 5/16. I have attached a picture of a head and put an X on the pin hole that needs enlarged, and circled the rest of the pin holes.
Also attached is a picture of the engine with the progress so far. I will be cleaning the engine and paint it soon.
#56
Yes, the one dowel pin needs enlarged, should have mentioned it. The Felpro .040" head gaskets may help with intake fitment. I could not get Ultraseal intake gaskets on a stock 76 350 with shim head gaskets. You may have some luck on your side but run with it.
#57
I knew there were some mods that needed to be done with the dowel pins, but there was a lack of information about exactly what online. Since I didn't have the 4A heads off when I turned in my #6 heads to the machining guy, I tried to find the info online, but all that is mentioned is "one pin needs enlarged", some even says you need to drill a new hole. I hope this post will be helpful to someone else who's looking for the info.
Sooo, Olds 307 and 403, did you take a look at the compression chart I posted, do you think I filled in the numbers correct? What do you think about hp/tq numbers? Will I be close to my goal, 300 hp/400tq? Or am I dreaming?
Sooo, Olds 307 and 403, did you take a look at the compression chart I posted, do you think I filled in the numbers correct? What do you think about hp/tq numbers? Will I be close to my goal, 300 hp/400tq? Or am I dreaming?
#58
The later motors have the pistons closer to deck factory, more like. 020" below deck. Otherwise they look close, Felpro head gaskets are .041" compressed. So you should be slightly under 9.5 to 1. You should be at 300+ hp and 400 ft/lbs. Too bad you can't fit the RPM intake, it would work well with your new combo.
#59
Those numbers actually gave me 9.526:1! Can't wait to get this engine started!
I put in the numbers on Comp Cams "CamQuest" which have a "Dyno Results" tab, it surely is overly optimistic, but if it is at most 10% off, I'll be happy! Look at the picture of the "Dyno chart" I posted...
I put in the numbers on Comp Cams "CamQuest" which have a "Dyno Results" tab, it surely is overly optimistic, but if it is at most 10% off, I'll be happy! Look at the picture of the "Dyno chart" I posted...
The later motors have the pistons closer to deck factory, more like. 020" below deck. Otherwise they look close, Felpro head gaskets are .041" compressed. So you should be slightly under 9.5 to 1. You should be at 300+ hp and 400 ft/lbs. Too bad you can't fit the RPM intake, it would work well with your new combo.
#60
Goal reached!
I managed to reach my goal for my latest period off work (I work 7 days in a row in Norway, and then have 7 days off)! Engine painted today! Very happy with the color match, this is Bill Hirsch engine enamel, it's labeled Cadillac -77 - 81, but it is GM Corporate Blue.
#62
Well.
Been working my *** off with this engine, while having the back pain from hell. I have managed to get the engine back in the car, and started, and have been trying to tweak it. But I can't get it to run well!
It is "missing a beat" in idle, and I needed to turn up the timing to around 30 degrees in idle to get it to run fair. And when revving it, coming down back to idle, it wants to stall and die.
I have had a much more experienced guy with me today, checking the timing, we have TDC, rotor pointing at #1 cyl post in the dist and timing mark on the balancer pointing at 0 degrees. All ignition wires are connected in the correct firing order.
I have had some issues with the rockers, when tightening them, they wanted to get stuck on the bottle neck of the rocker studs, so I have grinded down the bottle neck so I could set the valve lash to zero plus ½ turn. I am going to open the valve cover tomorrow and see if there still is a problem with this, I was thinking if it is seizing and holding a valve open? Or is ½ a turn too much pre-tension on the lifters?
What the heck am I missing here? I'm losing hope.
Been working my *** off with this engine, while having the back pain from hell. I have managed to get the engine back in the car, and started, and have been trying to tweak it. But I can't get it to run well!
It is "missing a beat" in idle, and I needed to turn up the timing to around 30 degrees in idle to get it to run fair. And when revving it, coming down back to idle, it wants to stall and die.
I have had a much more experienced guy with me today, checking the timing, we have TDC, rotor pointing at #1 cyl post in the dist and timing mark on the balancer pointing at 0 degrees. All ignition wires are connected in the correct firing order.
I have had some issues with the rockers, when tightening them, they wanted to get stuck on the bottle neck of the rocker studs, so I have grinded down the bottle neck so I could set the valve lash to zero plus ½ turn. I am going to open the valve cover tomorrow and see if there still is a problem with this, I was thinking if it is seizing and holding a valve open? Or is ½ a turn too much pre-tension on the lifters?
What the heck am I missing here? I'm losing hope.
#64
Thanks Olds 307 and 403, but I'm starting to despair. Oh how I wish I could afford to pay someone to fix this. The back pain, which I gave myself when laying on the cold garage floor and tightening the transmission to the engine and awakening an "old injury", is killing me. It seems like I'm doing exactly everything putting this engine into shape again at least twice. First, the dipstick tube for the trans was in the way of getting the engine in place, so I pulled it out with great effort since it got jammed against the a/c box, and was rewarded with a big puddle of trans oil on the floor. Then put it back after the engine was in place, and tightened the bracket to the engine, only to have to remove it the next day, because the o-ring on the dipstick was swollen and mushy, so it had rolled up on the tube without sealing, making the trans pee all over the floor with almost as much oil as I already had mopped up... And not to mention the radiator, that was all installed and ready for coolant, only to have to remove it because the fan shroud can't be fitted with the radiator in place since there's not enough space to get it passed the pulleys on the engine...
And tomorrow I will set the rocker arm lash again, for the third time. But Hey! Third time is a charm, right?
I feel like something that the cat dragged in. Or better yet, something the cat ate, and threw up on the living room carpet...
Wish me luck. Please?
Sigh...
Rant over.
And tomorrow I will set the rocker arm lash again, for the third time. But Hey! Third time is a charm, right?
I feel like something that the cat dragged in. Or better yet, something the cat ate, and threw up on the living room carpet...
Wish me luck. Please?
Sigh...
Rant over.
#66
It should make a huge difference in performance. Even try backing them off a 1/4 turn and start it. I hate adjustable rocker arms. I will never do another set with the intake on.
#67
I hope so, I can accept a moderate increase in performance at this point too, if it just would run right.
I have reset the lash to 1/4 turn now on the driver's side head, I'll do the other side tomorrow, need a rest now and spend some time with my daughter who are going to USA tomorrow morning. She is graduating from college, and have treated herself with a vacation to Los Angeles.
I have reset the lash to 1/4 turn now on the driver's side head, I'll do the other side tomorrow, need a rest now and spend some time with my daughter who are going to USA tomorrow morning. She is graduating from college, and have treated herself with a vacation to Los Angeles.
#68
Reset all the rockers now, and it seems to be running much better. I could even dial back the timing to around 16 degrees without vacuum. But it still wants to stall when coming back to idle from a heavy throttle opening. Normal acceleration is fine. It doesn't seem to be spinning heavy (with resistance), no strange sounds. Starts very easily.
I have about 13 in/hg of vacuum at idle, is that fine?
My temp sensor seems to have quit working, cable seems fine since the gauge needle pegs all the way to the right when I ground the cable. No change when I ground the sensor itself, in case that was the problem. Because of not having a temp reading, I haven't driven the car yet.
I have about 13 in/hg of vacuum at idle, is that fine?
My temp sensor seems to have quit working, cable seems fine since the gauge needle pegs all the way to the right when I ground the cable. No change when I ground the sensor itself, in case that was the problem. Because of not having a temp reading, I haven't driven the car yet.
#70
That vacuum sounds right with that cam. Is the Qjet modified or all stock? I went from 8 to 1 with a 204/214 cam to 9.6 to 1 with the same 204/214 cam and 1.72 to 1 roller rockers. I needed the Qjet completely reworked, would barely idle and ran horrible. Also make sure the fuel filter is new as well. It may need some retuning. My motor went from 140 to 142 psi all 8 cylinders to 170 to 180 psi with my head change. It sounds good in the video. Get a new temp sensor before the first drive. You may find the 403 runs warmer with that much more compression.
#71
That vacuum sounds right with that cam. Is the Qjet modified or all stock? I went from 8 to 1 with a 204/214 cam to 9.6 to 1 with the same 204/214 cam and 1.72 to 1 roller rockers. I needed the Qjet completely reworked, would barely idle and ran horrible. Also make sure the fuel filter is new as well. It may need some retuning. My motor went from 140 to 142 psi all 8 cylinders to 170 to 180 psi with my head change. It sounds good in the video. Get a new temp sensor before the first drive. You may find the 403 runs warmer with that much more compression.
#72
Mine is also like that, a plug on top and I slotted the APT for screwdriver. I currently have it turned in two turns for the more power setting. You should be able to adjust that then. You may need a bit more fuel in the idle circuits so adjust your mixture screws as well.
#73
Yes, exactly, a plug has been removed and the hole tapped for threads, with an Allen head plug screw in the hole that can be removed, and then you can use a screwdriver to adjust the needles (or APT?) up or down. I also had an electric choke installed.
I was actually planning on buying an EFI for it, but moved those plans into the future when I found the damage in the engine. It might happen for next year.
I was actually planning on buying an EFI for it, but moved those plans into the future when I found the damage in the engine. It might happen for next year.
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