Well as some of you may know I put a hole into a water jacket trying to do the relief work for the rod bolts on my 383. After the fact someone told me that stock rods are really hard to clearance. Who here is running stock rods in their 383?? Did you have a lot of trouble or is it just my luck?

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Riccioli Performance Motorworks

--RPM Racing--

-Currently building first ever engine. 383 with Super Ram plenum and runners, Edelbrock lower intake, Bosch 24# injectors, AFR 190 heads, MSD ignition.
-Will be installing Baer Brakes
-Will be installing full Spohn suspension in rear
-Art Carr 700R4 trans??


Attention Everyone!!! I will be changing my name on the message boards to HardcoreZ28 sometime in the near future. Just wanted to let everyone know.

 

Im using a stock style rod. (that sounds bad). I think it may be the reason my car is slow. When I built my motor I worked at a machine shop. I clearenced the top of the rod bolts to clear a very small cam (.4 lift) I stabbed in a new cam without checking clearances and fear that I might have damaged the cam. This is just a hunch and Im going to tear the motor apart before I put in the mack daddy cam. Man I wish I would have sprung for cap style rods. You must have ground the block way to far to of hit a jacket. That or the block was a poor casting. Ive built several other 383's (most with stock rods) and never had that happen. When you clearnce them there doesnt have to be a huge gap between the rods and the panrail, bottom of cylinders. Steel does not stretch that much. Next time take baby steps at grinding. Im not flaming you, just trying to help. Then you will run into the cam problems. The way to the eliminate the cam problem is to run a small base circle cam. Thats only if you dont have a hydraulic roller.

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87z 383,afr 190's, comp hyd roller(242/248-.540/.562,114 sep),Ported and polished mini ram, 30lb inj, 3.42 gears, tremec 5spd, , 1,3/4" slp headers, speed pro bank to bank-wb02.
"Just remember children, no man can beat you once youv'e found the cliterous." 'chef'

 

87, you will actually have more clearance problems with a little cam than a big one. I know it sounds weird, but....

You don't make a cam "bigger" by making the lobes taller. They're pretty much all the same height. If they were any taller, they wouldn't be able to fit through the cam bearings. Instead, since lift is the difference between the tip of the lobe and the back side, you make a cam "bigger" by grinding the back side down. That's why you have to use longer push rods when you start getting into big cams. That's also how you can take a cam and make it "bigger" by doing a re-grind. So, by running more cam, you actually ease the clearance issues.

You're right about the rod-to-block thing. Most of the time there's enough metal there to clearance without hitting water. But some blocks have too much core shift for that. Paul's luck basically ran out on that one.

I usually shoot for about .050" of clearance, but I'll take .030" if I have to. I don't like for it to be less than that because the crank does stretch some at high RPMs, and it grows with temperature too.

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"So many Mustangs, so little time..."
ICON Motorsports

 

Rb your right, I didnt make it clear when I stated it was a small cam. Actually the rod bolts dont even hit the cam at the top of the lobe. My fear is that I didnt check for interference when I put my cam in. The lobe profile is different between the l98 cam I clearenced for, and the crane that is in the car now. I only shaved about .030 off the rod bolts that were hitting the l98 cam(2 of them). The bottom line is that I half assed it when I put the crane in for sake of time. Soon I will find out if my fear has merit.

 

Well I had everything together and there was no hitting the cam or the bottom of the cylinders, but on the bottom of the cylinders I only had .010 clearance in a lot of spots. I was trying to make them atleast .040 and I hit the damn water jacket. I hope it was just a case of really bad core shift because I'll die if it happens again when I get another block. I'm almost thinking about having my machinist assemble the shortblock so if he hits water it's his responsibility, but then I won't be able to say I did it all on my own.
The fact that I'm running ARP rod bolts and not stockers shouldn't make a difference right?

------------------
Riccioli Performance Motorworks

--RPM Racing--

-Currently building first ever engine. 383 with Super Ram plenum and runners, Edelbrock lower intake, Bosch 24# injectors, AFR 190 heads, MSD ignition.
-Will be installing Baer Brakes
-Will be installing full Spohn suspension in rear
-Art Carr 700R4 trans??


Attention Everyone!!! I will be changing my name on the message boards to HardcoreZ28 sometime in the near future. Just wanted to let everyone know.

 

Good question...

You are using the ARP rod bolts specifically for 400s, that have the surface in question of the bolt head chamfered to provide clearance, right? If not, that would definitely set you up for having alot of clearance problems. That chamfer is good for at least .060" of extra clearance.

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"So many Mustangs, so little time..."
ICON Motorsports

 

Yes I have the 400 rod bolts, but the side I'm having clearance problems on is the rod cap side with the nut.

 

Oh, I didnt know you were running the 5.565" 400 rods. Sorry, I was reffering to stock 5.7" rods. Either way you should only have to clearance the block .030" max at the bottom of the walls. I hope it doesnt happen again to you also.

 

I am running the 5.7 rods, I just have the 400 rod bolts. Is that a problem?

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Riccioli Performance Motorworks

--RPM Racing--

-Currently building first ever engine. 383 with Super Ram plenum and runners, Edelbrock lower intake, Bosch 24# injectors, AFR 190 heads, MSD ignition.
-Will be installing Baer Brakes
-Will be installing full Spohn suspension in rear
-Art Carr 700R4 trans??


Attention Everyone!!! I will be changing my name on the message boards to HardcoreZ28 sometime in the near future. Just wanted to let everyone know.

 

I "had" stock 400 rods AND rod bolts in my 383. After 2 years of racing and shifting at 6400 rpm they finally let go. It's amazing the rod bolts lasted that long but the performance figures don't lie.


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Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z Pro ET Bracket Race Car
383 stroker (carbed) with double hump cast iron heads and pump gas
461 Big Block installed and ready for the 2001 racing season

Best results before the 383 blew up
Best ET on a time slip: 11.857 altitude corrected to 11.163
Best MPH on a time slip: 117.87 altitude corrected to 126.10
Altitude corrected rear wheel HP based on power to weight ratio: 476.5
Best 60 foot: 1.662

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley

 

Still wondering about those bolts. They are the right ones right?

 

I ordered the kit from Speed-O-Motive, and the rods are 5.7 with ARP hardware and they come in already ground for clearance for the cam. Maybe ought to look at them. Then all you'll need is clearance again for the crank.

Sorry for the mis-fortune.

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350 4 bolt main, Speed-O-Motive 383 stroker kit, re-sized rods ground for clearance,TRW Forged pistons,10.7:1 compression,HPC Coated RPM intake, Speed Demon 750 cfm carb,World Products Sportsman II heads,2.02/1.60 valves, Comp Cam 1.6 roller rockers, Comp Xtreme 284 cam,240/246@.050 with .540 lift,Crane pushrods,ATI damper,Proform HEI and MSD6A box,HPC coated 1 5/8 headers, 2.5" exhaust with 40 series mufflers,TH350 with Hughes 3000 stall, Powertrax NoSlip Locker, 4.11 gears.

 

Paul,, dude,, you need to get someone inperson to help with your engine. A 383 is not the easiest build and it's obvious you're stuggling with it. 5.565 (400) rod bolts are shorter than 5.7" (350) rod bolts due to the differences in the rod design (cam clearance issues). I've never measured the 5.565 bolt to see if they COULD fit in a 5.7" rod,, but I'd think that the bolt would not be long enough for full engagement of the nut (if at all). So I'd bet you either have one rod or the other,, not a mixture,, unless you have 5.565 rods with 5.7" rod bolt,, now that could be an issue. I've clearanced a few 350 blocks for 3.75 stroke and 5.565 rods and 5.7" rods and if you got into a water jacket,, you ground entirely too much or have some serious core shift,, which means the block is not suitable for hiperformance use. I swear I mean no offense,, but you really need to get someone in person to help you,, even if you have pay them!!!! It'll save you a lot of head and heart ache in the long run.

 

The Roc.....I don't really think I need someone to watch over my shoulder. That's really the only issue I had. The whole shortblock was assembled and I was about to put the oil pan on when I noticed that there wasn't enough rod clearance on the bottom of the cylinders. Other than that it was all good. I guess I just have to check on those rod bolts and rod sizes again and then hope to get a better block.

 

Yes they are shorter, the shank is shorter so that the 400 didnt have any cam problems like I was saying. They will not work in 5.7 rods unless you do some extensive milling.

 

Dang Paul, sorry to hear your not rolling yet. My machine shop and the guys I got my stroker kit from said to just make clearance for a paper clip. I went ahead and used one of those thick paper clips. I really didnt seem to remove much though. Im using a stock type rod that was ground down for clearance. Basically they ground the bolt down on the cam side.

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Mark Lock
- 86 IROC-Z - SuperRammed 383/T56
- -= IROC Online =- - The site dedicated to the IROC-Z

 

When I'm home from college this weekend for Easter I'm going to have to double check the p/n on my rod bolts, but it sounds like you guys are saying 400 bolts wouldn't work right in 5.7 rods, and mine fit fine. I guess I'll check the rod lengths again too. I really don't understand why I had to take so much material out though. Is it possible that my block had that much core shift? By the way, if anyone in the NJ/PA area has a block that they want to sell me please e-mail me...I'm having a tough time finding one.

------------------
Riccioli Performance Motorworks

--RPM Racing--

-Currently building first ever engine. 383 with Super Ram plenum and runners, Edelbrock lower intake, Bosch 24# injectors, AFR 190 heads, MSD ignition.
-Will be installing Baer Brakes
-Will be installing full Spohn suspension in rear
-Art Carr 700R4 trans??


Attention Everyone!!! I will be changing my name on the message boards to HardcoreZ28 sometime in the near future. Just wanted to let everyone know.

 

Since nobody has actually said it I will: DO NOT USE 400 ROD BOLTS IN A STOCK 5.7" ROD! NO NO NO NO NO!

THey're not JUST shorter although that reason right there basically rules out their use by itself.

I jsut built my 383 using stock 5.7" rods that came with my cheap-o-motive Speed-o-Motive kit. The block needed quite a bit of material ground out from the bottoms of the bores and I didn't strike water. I also didn't have to grind down the rod nut at all to gain the clearance.

I had NO clearance problems with the head of the rod bolt hitting the cam. I don't know what rod bolts were included with the kit but I could look at the receipt tonight when I get home if you send me an email. Probably stock replacement rod bolts since I didn't think to specify ARP (my mistake).

I also had to grind a LOT (and I mean a LOT) of material out of the bottoms of the bores where the opposite bank's rod nut would contact the bottom of the bore. I'm talking probably just shy of 1/4" of clearance!



[This message has been edited by Damon (edited April 11, 2001).]

 

Damon thanks for the reply. I had to grind a lot out of the bottome of my cylinders too on the first block. I might just have my machinist assemble the shortblock so if he hits water he has to fix it this time.