solo20

update got an email from SFI REP about the summit flexplate


"
We can confirm that Summit Racing Street and Strip is properly tested and certified to SFI specs. They have a private label agreement with one of our SFI participating manufacturers.

Thank you,

Suzanne

-----Original Message-----
From: Suzanne Allen
Sent: Wednesday, August 13, 2014 1:47 PM
To: ******************
Subject: FW: Contact Form submission from SFI Foundation"

and I just got my summit flex plate to day

pic host

senicalj4579

iTrader: (41)

Well that sounds good. Thanks for posting. Mines been good so far.

solo20

no problem man I was about to return it if I didn't get a response from the SFI rep took them a while for them to find out who was making that flex Plate for summit racing

mrvedit

Yes, that is good to know. And impressive that SFI was reachable and gave you a personal reply.
And sorry if my "doubting Thomas" wasted anyone's time.

Jake's Performance

iTrader: (2)

We carry the PRW brand Platinum series SFI flexplates. A little thicker and heavier than the Summit ones. The Summit flexplates seem decent, they may be the PRW Gold series.

senicalj4579

iTrader: (41)

Hell no. Thanks for making us aware. I as well as others appreciate a lot of the info you share on here


Thanks Jake

drone

iTrader: (5)

suprised the cat flexplate isnt being discussed. I replaced my TCI with it. Wayyyy cheaper and it fits like stock. SFI certified too. Been in my stalled car for 4-5 years.

sbca96

Whats a good quality inexpensive replacement for stock HP levels? I have a high
miles engine that I found a crack in the flexplate from the trans shop leaving two
of the 3 TC bolts loose. I need a new flexplate and found one on ebay. Problem
is, there is SO much mis-info and terrible cross references I can not decide which
one to get. Someone offered up a used 5.3L, but I was told it wont fit.

GM says that 12602448 is correct or 12654640 is the new number, but the one I
found on ebay is 12637677. The FLAPS list FRA-471 Pioneer brand is correct, but
it crosses to 12563136 which is yet another number. They list internally balanced
and externally balanced, I was told I need a flat version, yet the one I took off is
dished. I have a few threads over on Nastyz28 about my saga, its just not worth
getting into it all here.

Anyway ... the driveplate/flexplate inspection did not go well. I noticed a faint
line on three of the flex zones. After a cleaning with a scotchbrite pad I see on
one of them it catches my fingernail. It hasnt broken through yet, but I see it
as a junk part now. You can see a faint bump in the middle below the "GM" stamp.





Here is the other side .. looks like a crack to me.





This looked like a crack until I cleaned it up.



Tom

01ssreda4

iTrader: (96)

That flexplate looks fine to me.

sbca96

I ended up ordering a FRA-471 Pioneer brand from Rockauto for $54 dollars.

Thanks for all the help.

Tom

KILLERARMY

What do you mean by stamped flexplate? I have the Hugh 4004x flexplate. What is the pro and con about this Hughes Flexplate.

chuckd71

iTrader: (23)

I just picked up the B&M from Amazon for $75ish to replace my stock one that might or might not be a bit warped. I was going to have to take it off and put a couple shims between it and the tc anyway, so figured might as well replace it. It looked to have the bolt pattern to match up to my 200-4r, and Summit's site says that is it's purpose so I'm hoping it will work.
Anyway, just as a data point (and you might already know this) it is not flat, it has a slight hump in the middle where it mounts to the crank. I'm hopeful that this will take up the slack that I would've used shims for.
Here are the stickers on it, I know nothing of SFI but it might be of interest to someone.
Excuse the under desk mess, I'm only living in this place temporarily.

Circle-D_Brian

What you see above is a standard dished flex plate. It has the LS 11.06" pattern as well as the smaller 10.75" gm pattern. If you are running a standard 2004R converter, you will need a pilot extender to properly engage the crank, and you will use the smaller of the two bolt patterns. Check out the sticky at the top of this section to learn why some flex plates are dished and some are flat...

-Brian

TimE

iTrader: (8)

I have read through this thread and considered starting another but felt it might be a better fit, for future search reference, to post here...
I want something that will be safe to a 6300-6500 rpm shift and handle 500 rwhp. This will be for a 408"/4l60e with 3800 stall. I have busted my budget so if I don't need a $300-400 flexplate, I would rather not spend that much (but will if necessary). So my questions are as follows...

1. What is the benefit of going from stamped to machined?

2. Would a stamped Hughes or PRW Platinum hold up, long term, for 99% street use?

3. Are the machined flexplates worth the extra $100-200 (prefer fact vs. opinion, please)?

4. What, if any, would be the benefit of an aluminum flexplate?

TimE

iTrader: (8)

No reponses... Guess I'll try my luck with the Hughes.

Circle-D_Brian

1.In our experience, going from stamped to machined, you will get a better fit. We have seen the stamped flex plates come out too tall or too short meaning you are left with improper converter clearance which can wipe out pump gears if not dealt with properly.

The stamped plates we have also seen require starter shimming due to incorrectly sized ring gear or out of round issues. I think these problems are just due to mass production, and not necessarily the norm.

2. We have many customers using the stamped SFI ones on daily drivers without issues. Machined ones too. If you don't have issues initially, you're probably fine for years. We have seen some crack however. Primarily around the crank area. We never see the machined ones crack.

3. Not sure how to answer that question as everybody has different thoughts on value

4. Less weight is the benefit of an aluminum flex plate. This is rotating mass, but we haven't seen huge gains one way or another on the street car level FWIW.

-Brian

TimE

iTrader: (8)

Thanks for the detailed information Brian! I had already ordered a Hughes when I saw your response. I will fit it up and if there are issues with it, I will send it back and order a machined one. Probably should have gotten a billet but since I won't be racing it much, if at all, I went with the stamped.

If I swap to a 4l80e later, I will plan for a billet one. If it get's an '80e in it, it's gonna get beat on alot harder...

shepss217

iTrader: (5)

I went with a b&m for around $100, my brother has been running the same one for over 4 years so far on his sbc s10 going mid to high 9's. I thik it will hold

shepss217

iTrader: (5)

I will get a picture of my stock flexplate and show you guys what just a stall converter and some RPM's can do to the stock ones. Why would you put another stock replacement in there knowing how much work it is just to save a few dollars? And not even an ac delco at that. You just three away $54 cuz you will be replacing it again

shepss217

iTrader: (5)

To sum it up i had a 1/16" crack that started on the teeth that the starter catches and went all the way thru one of the converter bolts to the center of the plate. I was wondering where my vibration has been coming from for over two years and thought it was driveline issues. Turns out i was wrong