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what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 5:08 pm
by savagecowboy_69
just curious what 3800's came with out balance shafts and were they obd 1 or 2,plus my instructor told me about something called the t-top buick motor ( dont qoute me it was loud in there when he told me) its supposed to have twin turbos stock or something like that. just curious about this cause my intructor mentioned balance shafts in class and then told me about the buick motor thing please help he thinks the buick motor might fit in the series one bonnies

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 5:21 pm
by 00Beast
No 3800 I'm aware of came without a balance shaft, nor did ANY come with twin turbos OEM. Sounds like your instructor is talking out of his you-know-where. What's your beef with the balance shaft?

All of the turbo buick motors were designed for RWD cars, so they won't be configured at all for a FWD Bonneville.

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 5:28 pm
by J Wikoff
Sometime before they called it the 3800, there wasn't a balance shaft, IIRC. Early to mid eighties I think. The term "oddfire" is coming to mind for some reason.

He might have been talking about "T-Type". You could get a Regal T-Type with the turbo 3.8 at the same time as the Grand National. They were the same car with different trim for the most part. It wasn't twin turbo though. The later ones had intercoolers.

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 6:17 pm
by savagecowboy_69
that sounds about right (t-type)will that block match with the modern 3800 parts what was the differences in the motors im trying to figure out why he brought it up when i asked about removing the balance shafts was it just for refference or was he saying to check it out because i might be able to do something with the older blocks that didnt have balance shafts

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 6:54 pm
by 01bonneSC
What are you trying to do with this? The gurus will chime in if you give more details....

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 6:56 pm
by 00Beast
IIRC The Pre LG3 3800 is different and nothing will match from a newer 3800. Even if you get an LG3/LN3, the only parts that would match would be Series I parts.

I'd love to know what you're doing with this and why you're asking all the questions. If you're just curious, great. If you have a project, we'd love to hear about it and help you through it.

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 7:09 pm
by repinS
I think might be the LG3 (1987 and early 1988 Bonneville) that doesn't have a balance shaft.

Not a mechanical problem, moving to General Chat.

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 7:30 pm
by savagecowboy_69
just curious but if i could find a motor that didnt have balance shafts i would like to put it in my car i am trying to get performance without switching to a series two( i.e. obd2) also my instructer just sort of got me thinking

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 7:44 pm
by repinS
I don't think you could really gain much by deleting your balance shafts, other than more vibration and a motor that could shake itself to bits over time. All for a tiny bit of power?

Is your '92 SSE supercharged?

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 9:17 pm
by Jrs3800
The balance shaft was there to counter act the vibration of being a 90* V6 with a 60* firing pattern...

The LG2-LG3 were all without a balance shaft... Last year of production for the LG3 Vin 3 3.8 was 1988... This was also the first year for the 3800 Vin C, using the balance shaft... Every 3800 produced used a balance shaft..

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 9:22 pm
by willwren
Without a balance shaft on a 3800 90° V6, your motor will be short-lived. That mod is for a track queen ONLY.

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 9:23 pm
by 01bonneSC
Guess it should be stated that the 3800 is different than the 3.8L(231)

http://www.gnttype.org/general/v6hist.html

http://en.wikipedia.org/wiki/Buick_V6_engine


What type of performance are you looking to get out of your car?

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 9:41 pm
by BonneMe
90 degree V6 are naturally unbalanced by nature. Building a 3800 without one is not going to 'freeup' some power like an underdrive pulley set.

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 10:14 pm
by willwren
And then slowly shake the crank bearings and mains into oblivion over time. Worth it? Not for a daily driver.

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 10:55 pm
by savagecowboy_69
ok cool was just curiuos like i said my instructor got me thinking he said he had never heard of a motor with balance shafts being turned into one without and i was curiuos if anyone knew anything that would slate my curiosity. thank you for the info.

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 11:03 pm
by 00Beast
The only reason to do a "balance shaft delete" is if you NEED to run a double roller timing set on a very high performance engine, the gear doesn't clear the set, and you only need them if you break timing chains normally. Not something any Series 1 has experienced, and very few S2's have.

Re: what 3800 came without balance shafts

Posted: Tue Aug 09, 2011 11:13 pm
by willwren
First of all, there is no double roller set that will work on a S1 (and yes, that's really the only GOOD reason to delete the balance shaft).

Secondly, there IS a S1 that needed it, but without a double roller that will work, I had to pursue other options:

viewtopic.php?f=9&t=3518&p=34912&hilit= ... ket#p34912


This is what happens when you load your valvetrain up with more stress. High ratio rockers and stronger valve springs to fix valve float at the top of second gear. It's also (as stated) the only reason to delete a balance shaft, and if you do, you cause other problems as I've stated above.

So I guess it is something the S1 has experienced. But like I said, I chose another route to solving the problem without going to the impossible S1 double roller which doesn't exist, and my fix has proven effective for the past 3 years. ;)


(but maybe that's another story)



Deleting the balance shaft is probably only good for about 5hp. Certainly not worth the risk of the wear and tear on the internals that it was designed to prevent.

Re: what 3800 came without balance shafts

Posted: Wed Aug 10, 2011 1:59 pm
by savagecowboy_69
ouch well thanks for the info, oh btw while i got u guys does anyone know where i cant get cheap replacement front and rear bumpers mine are dead

Re: what 3800 came without balance shafts

Posted: Wed Aug 10, 2011 5:08 pm
by 01bonneSC
Hey cowboy,

What are you trying to do with your car? We can help you go quicker, safely!!