|05-12-2014 11:02 PM|
|gonzo08383||I break mine in using no breathers but instead two pcv valves. The object being to create vacuum in the crankcase. It helps the rings seat quickly. Ive been told this method can cause the main seals to prematurely fail though. I don't know if it does help but it didn't seem to hurt my engines. Do you suppose ethanol fuel has anything to do with your problem? It's a very long shot but maybe? I can't believe you're having this kind of trouble! GM must be slacking in the qc dept. Good luck and let us know what you find.|
|05-12-2014 05:51 PM|
Just completed build on a 36 ford coupe with a zz383. Just finished break in with slightly over 1000 miles and I have oil concerns. Given the fact that I bought this crate some 6-7 years ago I doubt GM or the dealer I bought it from will listen to me. I note a lot of experiences in this thread. Question is whether there is a common problem. I may just buy cheap oil as I don't want to pull the engine or even go down from top or up from bottom.
|07-01-2013 01:31 PM|
Just as a note on oil consumption, I just put 1280 miles on the 57 Chev with the 283 PowerPack. 3/4 of a quart of oil was used for the trip. This on a 25 year old stone stock rebuild with a 0.040" overbore now with 80,000 miles on it. The extra 100cubes that the 383's have over my 283 should use more oil, all else equal. But you'd think that the newer tech in the 383's should seal up better than a 283 with the crankcase vent tube.
Good luck with the 383's guys.
|06-28-2013 01:29 PM|
|AutoGear||Boy, I really wish you the best.|
|06-25-2013 10:03 PM|
Im Back... GMPP Makes Good I Think???
If you have followed for the last 7 months or so I have had two GMPP ZZ383 Strokers that have been oil users. The first one GM replaced after less than 1500 miles because it flunked a leakdown test. So they sent a new one. That motor used oil at a lower rate, but still unacepatble. So thay had my installer try a few things and then had me put over 4000 miles on the motor. No improvement. Well I just brought it back, post 4000 miles, and GM has decided to send another motor. So I am hoping that three is my lucky number and after this motor is broken in I can finally drive my car without documenting everything I do. Just want to run my car and enjoy it. One would have thought that for the $$ I spent I would have been doing that almost 1 year ago.
|04-22-2013 10:31 AM|
|al_1959||I drove my truck yesterday about 75 miles and the oil level has not moved a bit so far. I must admit the dealer's service dept that I bought the engine from has been very good to deal with. This engine has some torque reminds me of driving a big block.|
|04-21-2013 09:45 PM|
|gonzo08383||most likely shouldn't use synthetic before the engine is broken in. usually takes 500 miles or so to fully break in a motor. I've built a few and none have ever smoked, ever. usual culprits are valve seals, improper ring installment, too much oil, leaking rear main(2 pc seals are infamous for this), wrong oil type. I recommend 15w-40 rotella for break in. switch to synthetic after 1000 miles.|
|04-21-2013 08:24 PM|
|airsmith||I have all GM gaskets of my motor. That was the first question the asked my installer. As if there parts are the best. lol... But given the way they they try to wear us down, that will probably be next for me... As mentioned earlier, this is not my daily driver and GM wants miles on the motor before they will investigate futher. So I am working on that and so for the consumption is better since they sealed the stems, but still under 1000/Qt.|
|04-20-2013 10:50 PM|
|al_1959||Looks like the intake gasket was my problem. The bottom side of gasket did not crush and oil was pulled from the lifter valley to Number 2 and 4. The engine does not smoke now when starting it or after an extended period of idling. I'll drive it for a few days and watch the oil level.|
|04-17-2013 04:24 PM|
|al_1959||The dealship replaced my valve seals and the engine still smokes. They pulled the right head and it was loaded with oil. GM instructs the dealer to now take out the rocker studs and seal them, replace the valve seals with umbrella type seals, and replace the Edelbrock intake gasket with a GM gasket. Before I carried the truck to the dealer I measured the vacuum in each valve cover with a inches of WC gauge with the pcv system unhooked. I noticed no vacuum on the gauge after a extended idle so I'd say the intake gasket didn't leak.|
|04-12-2013 10:48 AM|
|04-11-2013 11:39 AM|
Getting a bad felling
I am just bringing my car out of winter hibernation. I have been instructed by GM to put more miles on the motor (4000) before they will reevaluate my oil issue. I have another 1200 to go. Does not look good so far.
|04-11-2013 10:45 AM|
|fast383||i dont mean to be bitter about my previous post. but i was absolutely shocked and still AM shocked at how GM treats a customer who pays $5000 for an engine. No wonder why other companies are taking over the American market. wake up gm. the customer is always right!|
|04-11-2013 10:02 AM|
i returned my zz383 and got my money back. what a horrible piece of workmanship.
gm basically told me to pound sand and would not offer any help/warranty, the worst customer service i have ever experienced. i hope many people read this post and decide not to go with a GMPP engine. i was given the run around for 6 months.
never buying a GMPP ever again. horrible quality.
|04-11-2013 09:22 AM|
WOW, GM sure has had a lot of issues with the 383 engines. When they 1st came out years ago, GM had to redesign the pistons slightly oversize pistons(4.005) to help to quiet them down.
These 383's have been out for over 11 years now(since 2002), you'd think GM would have them down pat by now.
GMPP doesnt seem to be having the same issues with the HT383 (340hp) or the HT383-E (direct replacement for 96-99 GMT400 Vortec 350 trucks/SUV's).
The Fastburn headed ZZ383(425hp) and the HT383 and HT383-E all share the exact same longblocks(crank/rods/block/pistons) only differnce is the cam and heads. ZZ383 uses the 220║/230║ duration @0.050" lift and lift of 509"/.528" lift(p/n 12370846) and the HT383/HT383-E runs the same cam as the Ramjet 350 crate and teh GM marine engines with 196║/206║ firstname.lastname@example.org" lift and lift of 0.431"/0.451" witha 109║LSA(p/n-14097395).
The reason the engine pull so much vacuum isnt necessarily because of its stroke, its because of the discplacement itself.
The ZZ383/HY383/HT38/383-E) all use a 4.00 bore and 3.80 stroke which equals 383cid. You could have the exact same displacement engine built differently like 5.52" bore and 2" stroke for 382.9 cid. Both are 383 engines.
1 thing for sure, I would not be babying this engine around. The redline is 6000rpm, and I for sure would have had this engine there several times by now. The rods in the GM 383 engines are certified to 500hp.
The limited production ZZ430.430hp 350 crate, ZZ385-350cid crate, and the ZZ383-425hp/383 all use the same 210cc Fastburn heads. I wonder if GMPP has had issues with those engines as well?
I had a buddy install a ZZ383 in his 57 Chev, I'll have to check with him to see how its working.
good luck with your GMPP engines. I would love to have a ZZ383 engine, but for around the same money, a 525hp GEN 4 crate can be had. Or go grab a junkyard 6.2(376), drop in a cam and enjoy 500+hp.
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