I put a 3970010 350 block (its a ZZ383 came out of a automatic set I never used I went BB instead on that 69)So I put the 350 (383) in a 91 rs convert T5 conf. I got the whole freeking thing in with info from here for the flyweel and all headaches etc done.All headaches done and fit.Everything went great its in and ready to go.Its ready to go EXCEPT I do not know what starter to go with.I hold the gen 1 starter up in the whole and the bolt holes in the block are about a inch to the left.Gen 2 same deal.Gen 3 are straight and wont bolt as the starter holes are angled.Anyone have any info on what year starter to use and what config ? We have had 4 starters up to it and the flywheel sits exactly in the same place in center of the dust cover but the bolt holes are to the left.The block has the 2 holes with the exact offset for the starter they are just to the left about a inch.Where are we going wrong?

 

You are the first person who has ever asked this question, or that this has happened to, or has seen it.

Seriously...

A brief search, or even just reading through the forums and seeing what other people have already talked about, would have turned up a few hints though...

https://www.thirdgen.org/forums/tran...-v6-t-5-a.html

https://www.thirdgen.org/forums/engi...swap-list.html

https://www.thirdgen.org/forums/tech...r-problem.html

Just from the past few weeks. It's been posted countless times before those, with the same pics, the same description of the problem, the same denial on the part of the affected, and the same short list of possibilities for a solution (namely, either drill the right starter bolt hole, or buy an aftermarket bell housing).

And, it's not a "ZZ383" if it has a 010 block. The ZZ383 has a 1-pc RMS block. The 010 block was discontinued about 20-25 years before the ZZ383 came into existence.

 

Ok thanks, I take it I drill the block and heli coil it but would have thought within the tranny section where is told me how to do the trans config they woulda mentioned the starter issue prior to this. A starter should be made for this. Now as for the ZZ383 I will be awfull POED at SUMMIT racing and GM performance if its not a ZZ383 as that's what I paid for and they deck stamped it .The block states 3970010 .The motor build number itself is 1038 on the timing cover plate.30.30.200 ZZ383 Summit and when I changed the covers I saw GM performance parts.New Crate motor but it does have those numbers 3970010. Ive messed with enough 350s I just never stuck 1 to a T5 and was changing tranny and asked my parts guy what the who and he said yea.Then I come here read to use the I think it was a 85 flywheel for conversion (no mention of starter prob) then I yank the 5.0 TBI boat anchor out and get rid of it.Now I have no choice.Might as well look at the m22 m21 conversion now I planned to do later but I have 2 bays took up (no lift) with this car so its a now thing.Thanks

 

Yeah, the block is drilled and tapped for a heavy duty starter for the 168-tooth flywheel.
You have to use the 153 tooth flywheel, because of the T5.
The easiest solution should be to use one of those dual-drilled aftermarket starters, but I cannot confirm this.
The cheapest solution should be to drill and tap the block.
You don't need the offset pattern. Using the starter you called gen 3, if you can position it correctly on your block, with the 153-tooth flywheel.
As sofakingdom typed, 3970010 is a casting number used in the '70s for 350 blocks. A real ZZ383 can't be a 3970010 block.

 

Obviously, YOU didn't read the links, either....

 

Maybe its just a 383 I will need to check the paperwork but was sure I ordered the and was sure it was stamped zz383 on the tag on timing cover.
I could be wrong will check.

No seriously Im in a bad position with this convertible and thank him for coming through with that post and wish I saw it sooner. Is there anyway I can take a micrometer and start tiny and work my way out to drill that hole and heli coil it the way we did heads (years ago)on gen 1s to gen 2s etc. My first gen 3 and this happens.I love the car but Ive dumped too much $ in it in parts and a great motor to find a bolt hole headache.I had the motor on a stand waiting for another 67-69 or maybe gen 2 I liked then I walked into this convertable I guess I want out of now I dunno.I even have ALL the sensors transffered.I milled a piece here and there for them to work. My cherry pickers gone and motor stand and air.Cars ready to run just bolt on new starter.I kept everything it was gonna be a sleeper.Other than the 50 slots on the rear and cowl hood it just looked like a 5ltr .Thanks anyhow- Im very depressed and really pissed at parts guy who said NO PROBLEM . This is my daily driver I did a week project on.

 

Yes read links just NOT YOURS or I never would have done this.I have everything correct for the conversion BUT the bolt hole. I will agree I am a idiot I did not read MORE THREADS.If I cant work something out by tomorrow I gotta start thinking yank the motor (class A show installation) and sell a nice looking convertible without a motor fast.I got rid of the old motor when I bought the flywheel while my equiptment went out on the truck.Gone.This was my last Car to do.I am too old and broken back.So I dumped it all.All was left was bolt on starter EVERYTHING was new in the drive train.

 

Sick thing is there was nothing wrong with the motor I was just putting a new clutch in and was told hey since its your last toy dump the 383 in and I DID like a idiot,

 

Yes it's not too terribly tough to add that hole; problem is, if the motor is already in the car, it's a royal pain in the drain to lay up under there and get the required degree of precision. You only get one crack at it, and if you screw it up, you basically scrap the block.

The way I usually do it is, BEFORE I put the motor in the car, is to use an old starter nosepiece as a drill bushing, and a LONG 3/8" drill; I bolt it up with the outer bolt, locate it PERFECTLY, then just barely start the hole with that drill, then using the point of th ehole that it drills as a guide, drill it with a small bit then progressively larger ones, up to the tap size for 3/8"-16; then just tap it with a normal tap. No Heli-Coil necessary if you get the size right. But, getting it ABSOLUTELY PERFECTLY PERPENDICULAR to the surface, is CRITICAL; bolts don't bend.

Note also that starter bolt holes are "special"; there's a larger "pilot" kind of a section about 3/8" deep, because starter bolts are ALSO "special". THey have an enlarged and knurled section right behind the threads, and a similar one under the head, to make a "dowel pin" arrangement to POSITIVELY locate the starter in relation to the crank. SO I usually drill em all the way through with the bit that's the tap size for 3/8"-16 (which is a 5/16" IIRC), then drill the counterbore 3/8" deep with I think it's either a 25/64" or 13/32" (you can measure an actual starter bolt to get the exact dimension), then tap it last of all.

I have typed that whole explanation about why this is what it is SO MANY TIMES ove rthe years, I wish it would get made into a sticky; but that never seems to happen. And every couple of weeks, yet another person gets bit by it. It's a damn shame the mods on this particular board don't get a clue and help you guys out. But, oh well.... wish in one hand and sh ..... ummmmm,,,, ... ,,,,,, have a body function .... in the other, and see which one fills up faster, and that's the metaphor for real life, eh??

As I've said over and over again, there IS NO "magic" starter that will work. THe problem is the LOCATION of the inner bolt hole. Think: if the flywheel is smaller, the shaft and all the internal guts of the starter have to be closer to the crank; but if you can imagine a bolt in that inner hole, it's pretty easy to see that if the starter innards were moved over toward the crank close enough for it to work, a bolt in that hole would have to go RIGHT DIRECTLY THROUGH THE MIDDLE of the starter guts. It's not a question of "the starter" being wrong, it's a question of the BOLT HOLE being in the wrong place.

The starters that fit both bolt patterns only work IF THE RIGHT HOLE EXISTS IN THE BLOCK. That goes for all the aftermarket ones, the LT1 one, etc. etc. etc. etc.

Other choice is, get an aftermarket BH and a 14" flywheel, and drill the "rotated" T-5 pattern in it if it isn't already there.

Don't feel like an "idiot", we all have to learn somehow sometime. We live and learn, or we don't live long. The take-away from this is, you can't always search on the things you already know about, and expect to find everything; sometimes you just gotta sit down and start reading whatever you come across, and if you're lucky the jewel will emerge unbidden from the gravel. (Lotta gravel on this board sometimes)

 

Sofakingdom, I didn't read the links you posted. I understood the problem. I just thought that the swapping of bellhousing and flywheel would be way too costly and labor-intensive.
I'm glad to have confirmation that there's not any one starter out there that will solve this problem all by itself. I thought there might be, but better to know bad news than to falsely hope good news.
If I had to drill the block with it in the car, I'd sure find that brace that goes on the other end of the starter, and bolt that to the block, before trying to mark the new hole location.
And the Y-pipe changes the whole game, compared to the pre-'75 cars.

 

Did the 14" conversion from here without knowing of the starter hole.Your correct I got all part info and everything from here.I took a exact same tooth flexplate off the motor thats weird also.YES there should be a sticky on the conversion.Ive restored over 100 frame off gen 1 and gen 2s and never did a 3.Ive given a couple top guys here in this site nice gen 3s minus the motor and trans we pulled to stick back in a y88 or 10th etc.Suprised the didnt sound in.If there was a sticky on it I wouldnt be jammed as I got my part numbers here and from my parts guy-was told NO PROB and saw the conversion a time or 2 but didnt ask or care.40 years wrenching you would think I would not have slipped through the cracks on this one.Thanks that helps a lot !!!!! I am an old wrench rutner and have a couple questions and also what my plan is.1st I already did the conversion to the 14" flywheel (atleast thats what I think it was.I had to get I think it was a 1984 gen 3 flywheel to mate up to the T5 correctly . While I had that part here I at the same time mated it up to the flexplate that I took off the motor and they were the same other than the center hole IE the reason I have a 84 flexplate on a 91 T5. What makes me scratch my head is why the org starter (to the gen 1 motor) I dumped would not have worked if I made a dust cover ? It was hitting the same exact size flex plate with same tooth count I even took pics of the whole conversion you guys posted for my brother to post a thread properly on it.Your center bolt explanation makes sense though due to the bell housing,So I do have the 14" flywheel on it and did all that. I found about the starter issue right before I was going to tune it yesterday after I put the starter on.I even got the proper return line for fuel and trans/clutch conversion/hydrolics all new etc and all new parts all around done correctly.(your right was expensive)etc etc etc.I just dont understand why I took same exact size flexplate off even sat ontop flywheel to confirm it was exact why a starter dont fit other than I just havent taken the time to work out the obvious.------My plan. Cars together ready to run but no starter and headers but no exaust (was going to drive to exaust shop open headers) so I have a open area.I am thinking I level off the bottom of the motor where the starter mounts, I invert my sherline mill (its a small cnc mill I can disconnect the stepper motors) and mill up as you said like use of a drill.Your correct I can see its a 1 time shot.On another GM site the guys are just drilling them and taping them exactly as you say.I was looking for the mic numbers to mate up a measurement but your correct it is a common thing that is done to templete it off old starter.Now I do wish I would have known about the starter issue as I went through the threads collecting part info as a warning as NOW I already dropped the motor and installed the trans with the conversion and connected a thousand things etc.It would have been very easy to just drill and tap on the stand.I have heard from very sensible people on this matter but there should be a sticky about this starter issue.My equipt is gone now so I am stuck with drilling a hole under a car or I would just have gotten the bell housing as I did everything else thats been posted.YOU GUYS ARE CORRECT there is so many threads on this I even got all my part numbers/years and tips and tricks etc but nobody mentioned a starter bolt hole or it would have been done prior to install or just kept 5ltr and blown it.I do have a lot of room under there with pipes off and can only see my main loss would be a extra hole if I miss and keep contamination controlled by marking it then taping the heck out of everything and masking to seal it but I must leave a open reference point for straightness.EXPENSIVE MOTOR IM PLAYING WITH .What a idiot I am but the car is super nice.My pipe bender guy called this am asking where it was.Errrrrrr. I understand and thank you for the pilot stabeliser area of the bolt warning I understand all that.Ive turned wrenches for 40 years for a living and built gen 1 and 2s frame offs forever.Over 100 of them.Ive given some top members of this site very nice gen 3s in the past when we needed the 2 block and tranny back for a correct resto.Actually really surprised a couple did'nt sound in to help but not a common post area.I never did a 3 before and did not find solid correct reference on a clutch change and thought I would show one to help the kids out so we filmed it all in Hd etc.Figured Id drop the 383 in at same time and confirmed it here and with parts guy.Then this bolt.Yeeesh.I showed em how a idiot goes LOL .Ok well your posted plan helps with bit sizes etc.I would suggest a sticky as I got a lot of info here without even a hint on this site of a starter bolt problem.I would have prob just left the 5ltr in after all this I went through.When the wife sees exactly what I spent ewwww.Thanks for your help

 

I've never had my hands on a stock T5 - V8 bellhousing, but everyone here claims that it cannot be used with a 14", 168-tooth flywheel.
I do know that all the V8 / T5 F-cars were built with the 12.75", 153-tooth flywheels.
That 3970010 block was originally built with a 14", whether stick or automatic.
I hate that you have to try to drill it under the car, and I hope you get it perfect the first try.

 

I have several myself.

Here's pics of a V8 and a 6-cyl T-5 BH, that I ganked off of eBay, the world's largest archive of pics of ANYTHING that can possibly be offered for sale. Ignore the 6-cyl one for this discussion. (or for any other, except for why a 6-cyl BH won't fit on a V8 motor, for that matter)



The V8 one, you can see the bottom of it is much closer to the center than the top. Because of how "short" it is, a 14" flywheel won't fit in it, across there; not even without a clutch. It has to be the 12.8" one.

Interestingly enough, the 79 Z28 4-speed I had back when it was new, its BH would accomodate the 14" flywheel, but it used a 10.4" clutch. The BH had a kind of shape to it that excluded an 11" clutch from being an option. I guess they carried that to its logical conclusion in the 3rd gen design.