I have been racing for 48 years now took a 20 year vacation for Family and House but still racing.
What i want to tell everyone is be aware of crankshaft problems and rod bearing problems that could be directly asscocated with your motor mounting configurations. Knowing this is true on Big Block chevy and small block chevy even the SBC World block. what happeneds is when you are using OEM motor mounts and a 4 speed (this problems shows up faster with Clutch car ie:4speed) the motor mounts rip at the block and pull the main cap and register next to the 3 bolt mounts and pulls the bore or number 2 and 3 main caps egging the hole under torque and removing clearances of main bearings of 2 & 3 and start the process of distroying bearing surfaces and transfering materials to # 3 rod bearing and the longer it goes on the worse it gets. its a hard one to figure out and HP motors in a full chassis tube car never see this because the motor is usally mounted with a front motor plate and a mid motor plate leaving the middle of the block alone letting it do its job holding the crank and letting it spin. This is even been seen on a street car with 4 speed that hooks and goes. I wanted to share my greif with everyone so that this $$$$ sport is less money for you in the long run. This problem get amplified so much more with steel motor mounts to the point if you get 3, 4 runs on your motor watching oil youll find specks floating around proving that material is now in oil. So if your really banging them gears and hooking up and tearing up the track start with a front and mid motor plates and screw the oem motor mounting positions. I would believe that this would apply to all blocks made and the only diff. would be for how long it would survive. I have never seen any advertisments related to helping this problem becoming under control by any block manufactures. Newer blocks with side bolted main caps may have been a big improvment but i have never worked with these blocks. Chrys has a nice idea on their bottom ends.
To prove that you had this problem unpond removing your main caps they should be tuff to pull out of the block registries and need to go back in by tapping with a heavy object. if you main caps fall out sort to speak chances are you have this problem and especally if its main # 2 (next to motor mounts) and also at Main # 3 . if you have a 12 inch dial capliper you could measure the width of the registry and see that the easy to come out main caps are .001 to .002 outside the Oem block spec,s. while some people peen the registry tight up against the cap when installed, also you may see some heat marks in cap . The block will have to be line honed and corrected. At That point i suggest going with the steel main caps being installed and help the strength of the block to resist stretching at the main caps. and again do away with oem motor mounts. People that get into racing with a tube chassis car dont see this problem because the motor plates are the easies way to mount any kind of motor in a chassic and leaving the block side walls alone without stretching. The olds block is weak enough as it is so i would say right from the get go dont use the motor mounts period on any kind of HP appl.
The motor plates crack from the severe torque and hard launches witch brings me to the point of the automatic trans being easier on the shock and maybe the reason why it doesnt show up alot on these types of cars.
So beware of this problem and tell a friend, racing is money enough without the silent Killers working at your pocket book also.
If your an english buff please dont write me and correct my grammer. I get enough of crap about that go back to school and be a teacher. If you have something to add here please with all due knowledge add to thread.


Douglas star393@juno.com WWW.FriedbergRacing.com

That's a new one to me. I run an auto now, but this is the first one. Most have been sticks. I'm not doubting you though. I may not have made the power you did...

I will say and alot of you guys know I am a stick guy and have been for the last 35 plus years and have never heard of this problem or experienced this issue. I'm not saying this is not a problem because it makes sense to me. I will add that I check end play on all the motors I build and freshen because we run stick cars.
The only time I ran a block/motor plates is when I had my Bickel chassis car. We run solid motor mounts and rubber trans mounts on all our race cars and street cars. The blocks we run are mostly stock 350 SBC 010 4 bolt factory mains.
We have built a couple of bow tie blocks but I don't see wasting the money for what we do.
Thanks for the info. great post

The 4 speed car in question is a 3000 64 chevelle with 14.5 slicks and a 538 rear and 4 link 302 first gear and 3400 sinder iron disc, and 8000 rpm plus leaves and 900 plus HP 541 bbc . 4.5 stroke tall deck. Show no mercy. A camaro with sbc was other sim. problems. Also agressive driving.

Since the last few posts i made here i rebuilt my motor mounting system using a alum front plate. A mid plate mounting system that i used in my A body chevelle from a camaro sold mid plate from Chris Alston shop i reshaped it and Mounted directly and bolted to the frame with my frame mounts i made. A new block with steel caps i sent to a well know speed shop distroid my block by boring the block main holes .020 deeper into the block rendering my combination usless. ( be dam sure you know who is doing your machine work). I built a 4.0 stk 454 standard hole another new block tall deck and used the iron main caps 4 bolt of course with main studs and with a main stud girdle installed also after the second run lost oil pressure. End result all three center main caps were pushed out the bottom to the point of Gaulling the caps and block mating surfaces. The caps fell out of the block when unbolted. After measuring the registers no problems were noted showing any block pulling of resisters. End result a two fold problem one solved and one to go. hopefully steel main caps will help hold the crankshaft were it belongs. Just to much HP and Rpm,s for a oem tall deck with a crazy behind the wheel. To dam easy to make Horse Power and Torque these days with all these nice parts . Chrismas is coming soon so if anybody has a extra Dart or Merlin block collecting dust it sure would look nice under my tree LMAO. If all this infor will help just one person then these posts done there job. For all of us that love racing and we all know its turned into a money sport now better be careful on how fast you want to go and start with the aftermarket blocks and just wait alot longer before building anything. Me i like pushing stuff to its limitations and solving the problems.

Seasons Greetings Douglas

Well alittle follow up on this subject, with know issues on blocks i bought some billet steel main caps and a merlin rear main cap and using a bridge port mill i matched new main caps to block within .015 of a perfect hole size meaning the new steel main cap was still .015 smaller yet to allow for material removal for line honing or combo of line boring and line honing, i fitted the main caps into the registers with a .002 interference fit.(nice an tight) installed with studs and off to the machine shop as i dont have that kind of equipment. So around here theres a shop with 40 years or racing experence so i choose them Borowski in Ill. With all the different problems that you can run into with a block in racing steel billet main caps is a must on a high HP race engine. Ive been walkng up the ladder of HP over the years between RPM,s and HP the two cannot exist together without something given. In my case the rpm,s (9500) and HP (1000hp) N/A no power adders wont survive under iron main caps they walk all over the place even with a main girdle installed. Between the crankshaft flexing and weak main caps (4 bolt type) your at the end of the line. There just isnt enough material under the crankshaft to hold it together. I call it the strap of the main cap, thats the arc of the hole of the main cap between the two inner bolt holes, about 1 inch of material under the crank. So my advice is dont even start out with iron main caps if your going to build a race motor you going to need to have it line honed anyway so stop there and buy steel billet mains and have them installed.
Take a tour of the shop your having it done by ask questions like how old is your equipment how well do they take can of it and look at the stones and see if there junk at all even in the hands of well experenced personal junk cant make straight holes. Not good enough for a race engine. That was my mistake!!! Borowski had junk and by the time i got my block back they fucked up so many times trying to line bore it they sunk the crankshaft center line into my brand new block .025 and milled a additional .030 off my caps and now losser in the registers by .001. They stand behine there work alright , way behine. They admitted they fucked up and here its 1 year later and no replacment. Unless you have thousands of dollars for a law suit your fucked,in my case new block bored with head plate 3 months of hand grinding to swing a 4.5 stroke crank in it sonic testing and hard blocked steel main caps and paid for line boring and line honing. Not untill i got block home and measured and installed timing chain did i find this out. They Borowski,s never said a word untill i approached them with measured information. See i measured crankshaft center line with cam center line before i sent it to them and i also have 4 other new blocks same casting in june of 1992 all withing .001 of each other so they never measued themself when they received it and had no were to go but admit to there **** up. See the retired head machinist retired two weeks before they did my block and a young man tried to take over it was his first steel billet main cap block for him to do and after he fucked it up then they call back the retired guy to finish it up but it was too late crankshaft center line already had been dropped too far down from all the **** ups. My rotating assy will not work anymore and no one makes a timing chain set - .025 and now head gaskets cost 100.00 apiece compaired to 65.00 a set race engines need to be taken apart alot now the costs are up to 200.00 a set and no more line honing the block for clean up and hence a new block with no more life left. So iam fucked. Be carful who you have doing your machine work. Use a Purchase Order with sizes spelled out and have them measure it also in front of you, and if they wont sign it find someone else. Get a sign receipt for your items dropped off at any machine shop, engrave your ID on you items and spell out manufacture of your items also. Force them to be legit and responible or dont do business with them. Otherwise bend over and be ready to take it up the ass. Its so dam hard to find a GOOD machine shop these days word of mouth isnt. good enough but it helps for a start.
Cats makes a good steel billet main cap but there 1045 steel a set of 4 for 100.00. They also make them in splayed versions. Eagle makes a set of three using 4130 steel but only three buying two sets gets ya all four on your block done. The front main also walks as well as the rear main so i do all of them. I look for merlins rear main cap and get rid of the oem rear main also as merlin uses more nickel in there castings. End result start off with a Dart big M block with steel mains from the get go and save alot of worries. Its a $3200.00 pay out that not evenone can afford. But walking up the ladder of HP and RPM,s you will get there fast from a oem block. Dart willnot tell ya either what there block is rated for but its a better start. Sure you can run these oem blocks under 7500 rpms and have alot of fun but thats not me . Just some food for thought on this subject and watch out for the machine shops. Choose a shop that keeps up with current machinery and state of the art. Less chance of a **** up in skilled or unskilled hands.

This is an unspeakable nightmare situation, star. I am really sorry to hear about what they did to your engine...and then didn't say anything or admit to it until you forced them to with proof. You're out all that dough and you have an unworkable engine now, they should replace it and I mean way back when all that went down. This pisses me off. RIPOFF. I can't imagine how you must feel about it. Thanks for explaining all of it, and providing us with helpful information on future engine shop contracts. Again, I'm sorry that happened, man. Hope it can be resolved without a lawyer getting involved. Sounds to me like you might need one soon, though. WC1

been doing some posting and thought this would be some good reading

http://www.yellowbullet.com/forum/showt ... ost7437477

I did a block number two the same way using someone else,s services and at 840 HP at motor to 9500 rpms its sweet. Its just a 454 with 4" stroke at 4.250 bore no hardblock. I know theres more to be had with a good tune up and some timing changes but havent gottan around to that yet.

Saweet!!!!