What's up guys? Ok, I'm doing a swap from a 6 to an 8. Now, I want to know of the best alternative I should go. I HAVE found a '90 5.0 for $1000 I could use as the parts car. I have a '90 3.1. I originally wanted to go 350, but could I get the 305 close or even better than a modded 350 could go in terms of hp, etc.? I still need to keep this emissions legal, so, that plays a major roll on this also. Would an LT1 be a better choice? I'm having a hard time finding a 90-92 350 donor car around the Chicago area. I'm looking for the best performance/easiest swap I can do. I figured a 350 w/ Vortec heads and an LT4 Hot Cam would get me around 360 or so rwhp. Could I get that w/ a 305? Would it need much more work?
Please let me know what you guys think on what is the easiest/best performance swap I could do. I'm looking in terms of 300-350 or so rwhp. I want to keep up, if not SMOKE, the LS1's...especially kill the **** burners.

Thanks guys!

 

First off....$1000 for a 305 is way too much....even if you are getting a whole car with it...don't do it.
A simply rule to live by is that there is just no substitute for cubes in regards to power. Get a 350. If you can get your hands on a LT1, get that. It has been done so there are plenty of sources out there to help with the swap. Better yet, if you find a 350 block, punch it out to a 383 with your Vortec Heads and LT4 Hot Cam and you'd be able to hang with LS1's all day....depending on what kind of intake you fed that engine with. Stoggin Dickey Parts sells a 385hp 350cid motor that has the Fast Burn heads(aluminum Vortecs, nothing more) and if that dosile little engine isn't enough, throw in the LT4 hot cam, and the power goes to 430hp....kinda cool huh? http://sdpc2000.com/ only thing is, it's kinda pricey. But you can find a LT1 or L98 long block for a grand....so don't go wasting your money on 305's.....not to bash those of you who drive and mod them, I do as well, but a 350 would be a better bet on making your 300-350hp.
here's a link for some stroker kits just in case you come across a block you'd like to bore and stroke. http://speedomotive.com/CHEVY%20STRO...ANK%20KITS.htm
Good luck with whatever you decide.
Lc

 

Thanks for the advice.

Well, here is also ANOTHER alternative I was contemplating. If I go w/ a crate engine, what is it to get all the mounting hardware on there? I mean, like, Alternator brackets, etc...All the bracketry and the rest of the stuff as you would w/ a donor car block. I was told that w/ a crate, since they are "universal" engines, you have to make your own mounting holes, etc. into the block and heads. I don't like the idea of doing so...especially if Im spending upwards to $3000 on it. I'm just thinking in terms of practicality and what would be easier. I DO want to keep the TPI intake, and I've found those for like $2000 brand new. To be honest, I'd rather go all new parts, BUT, if it takes substantially more money and custom work, I'd rather not. The only reason I was going w/ the L98 350 from a donor, is that it would be a direct bolt on, and I would have all the accessories, etc right off the bat.

How much more of a deal would it be to say, go w/ one of those spdc crate engines?

Any info would much be appreciated.

Thanks a lot guys!

 

If you go with a creat engine all the mounting holes will be there (unless you change to something like an LS1) As far as your accessories my question would be will the ones you have oin yours fit a 350 block compared to a 3.1 block, I would think they would knowing GM, try finding someone that has a 90 with a 305 or 350 and compare them. Otherwise you could do what i did stop at your local salvage yard and pick up what you need, I got the whole front accessory drive for $100.00, including alt, air compressor, power steering pump, air conditioning lines, and bunch of other stuff.
Good luck.

 

ok, good to know...now, just looking at sdpc2000.com...the cheapest GM Performance engine is like $2300 (not bad for brand new)...BUT, they say, "Unless specified by GM, these engines should only be used in 1973 and earlier pre-emissions vehicles. "

So, that means I couldn't use it, correct? What would cause it to be non emissions legal?

I'm looking at the 330HP / 350 GM Performance Parts Crate Engine Assembly.

It ALSO says, "Note: This engine is not intended for use in fuel injected applications. For high performance fuel injection engines, please see our Custom Crate Engine selection."

So, that basically rules it out, huh? I was wanting to keep my Wiring harness setup and I MUST be emissions legal where I'm at.

Any ideas?

 

I am sure there is someone on here that can tell you the diff. Have you looked at the 360 hp TPI Vortec motor? It's more money but it comes with there base manifold ($400.00 value) and is designed for our cars. One thing i am finding out is these engine changes add up fast no matter how you do it.

 

No, I havn't seen that engine. How much? Is it emissions legal? Do you have a link?

 

http://sdpc2000.com/cart.asp?action=...=1577&pid=9009

Notice that this engine has the vortec heads, and the LT4 hot cam already installed. Plus it retains the stock TPI intake but adds a bit more power....considerable amount compared to a stock one. This engine should be fun if you want power....look at the torque number. Note also that you have to buy an EGR kit with it....but that will make the emissions people happy. You can find your bracketry from any 305 or 350 block and it will bolt up to a crate engine (especially this one) with no problems. Like MY85IROC said....just visit your local junk yard...and you could get the A.I.R compressor and some edelbrock headers that have A.I.R fittings to be even more emissions friendly. Hope this helps.
Lc

 

Thank you so much guys. You really helped clear a lot of things up for me. I think getting the crate would be the way to go in the long run. Plus, finding a 90-92 L98 350 car is just not going smoothly. Umn, well, that settles the engine issue, now what about the trans? Again, w/ the Donor car, I would have that too...my stock differential from the '90 3.1 would work fine, correct? How about the fuel pump? I've heard it would, but then heard it wouldn't. Wiring, I have the chart on how I need to rewire my ECM, but mine WILL work, so I don't need a whole new wiring loom. Any other information that I would need to know? I don't want anything creeping up on me, lol.

Also, w/ that engine, I would still need to buy the whole TPI intake plus injectors, etc. (From what I'm reading)

One more thing, w/ that engine, how do you think gas mileage would be? This isn't an every day driver, just a cruiser, but it WILL be driven a lot just for fun.

Thanks again guys.

 

ok, well, to make it easy...could I use all the sensors from my 3.1 for the 350? I'm seriously considering that 350 Crate linked above from sdpc.
Then could I just get these two things to complete the TPI intake?
http://www.sdpc2000.com/cart.asp?act...=1090&pid=5887
http://www.sdpc2000.com/cart.asp?act...=1090&pid=5857
I know I'd need the injectors, but, would that be it to complete it? Keep in mind, I AM converting my mpfi harness to TPI, and just getting a custom chip for the whole setup.

Thanks for the help.

 

It is possible to get into the 300s with a 305 but not without lots of work from everything from the suspension up. check out these crated motors, they look pretty nice.

http://cgi.ebay.com/ebaymotors/ws/eB...tem=2437570016

http://cgi.ebay.com/ebaymotors/ws/eB...tem=2437109774

 

You'd probably have to buy all new sensors for the 350 since it is a completely different block than the 3.1. But honestly, those aren't too expensive, depending on whether you go MAP or MAF. The stuff for the TPI setup you will need are....fuel rails, injectors, plenum, TB, runners, AFPR, and of course the little vacuum lines and wiring. That engine comes with the TPI vortec base ($400 value) so just find a LB9 or L98 car, strip the stock TPI junk off...run and port it and you should be good to go....just get all the stuff you need. Or there is a huge aftermarket for all that stuff, I'd just go with trying to find stock to save some money. Gas mileage shouldn't be an issue....about 15-28MPG depending on how well you tune it, drive it, and what else you have with it. that just depends.......but start measuring that long after you break in the engine. Good luck
Lc

 

There shouldn't be any problems with the rear end.. If you're looking to get some more power, changing the gear ratio and getting a limited slip would help a lot.

 

i did a v6 to v8 swap in my car. (3.1L MPFI to a L69 305 HOwith a holley 600cfm carb) i'm still running the stock 2.73 gears. they are nice for the highway.

$1,000 for a 305 is crazy... i traded a guy BROKEN laptop (LCD Screen broke) so i got the 305 long block free... it was a sweet deal cuz the head where port and polished

to my understandeing your 3.1L ECM will work just have to get a new chip... as for the wiring and all the sencors i don't know.

one more thing... you may hear on this web site that you may need to change the front springs to V-8 springs... this is not true. i'm runnign the v6 springs in my car with the v8 and its find.. and if you ask me they are better for drag racing.

your goign to run into some small bullsh*t when doing the swap like your going to have to move the brake line thats on the k-member (NOT a big deal at all so don't worry about it) there are holes in the k-member for the V8 and V6 motor mounts.

there is going to be some stuff that will happen that you won't see comeing... there always is. if you go carb (witch you CAN make pass emission....i'm from joliet,IL and i knwo tons of cars that pass that are carbed) the swap IMO will be alot faster and smoother.

as for the LT1 i'm not sure is you need different kind of motor mounts or not. if you just get a 350 liek the ZZ4 it will just bolt right in with stock V8 motor mounts from NAPA

 

I am going to keep Fuel Injection. I know it's more of a pain, but I don't think it should be too bad. As for the sensors, I already have a MAP system, and since my harness and ECM "Will" work, shouldn't the sensors work too?

As for the TPI itself. There is a guy selling a whole TPI setup (sensors, ecm, harness, manifold, tb, fuel rails, runners, etc.) from an 86 IROC for $100. I know the sensors, etc. wouldn't work, but is it a deal for the rest of the stuff? Should I get that, then just shoot for aftermarket runners? Or, should I just get all new off the bat? I know a new TB wouldn't matter, so the one that comes w/ that should be good enough.

Let me know your idea's!

Thanks again!

 

Is that TPI setup coming off of a 350? If you're putting a 350 in there and the TPI setup is off of a 305, you're going to want to replace the injectors with 22# injectors. Which, is going to cost a fair amount of money. Other than that, 100 bucks is a good deal if it's all in good shape.

 

I'm not sure what size 8 it's off of. But, I was going to get new injectors anyway. I saw some 24lb ones on SLP's site for like $100 or so for a set. Now, that seems pretty cheap, but maybe it IS true. As far as the condition of the TPI, I can't really tell that good from the pic, but it looks fairly good. It's going to need to be cleaned up, polished, etc...the usual stuff. But, as far as having all the physical pieces, I think it wouldn't be a bad deal. Probably the new runners would be a good idea too.

 

Also, I forgot to ask, would 24lb injectors be good enough for that engine? Would bigger be better? I know too big, and it would probably run rich. I found a guy that has 8 used Bosch injectors w/ 10k miles on 'em, for $100.

Let me know.

Thanks!!

 

Also, I forgot to ask, would 24lb injectors be good enough for that engine? Would bigger be better? I know too big, and it would probably run rich. I found a guy that has 8 used 24lb Bosch injectors w/ 10k miles on 'em, for $100.

Let me know.

Thanks!!

 

i have no clue.. i'm a carb man.. i don't like FI

 

Thanks though.

Anyone else have any idea?

 

Well, even though there is more power potential in a 350, i have a 305 TBI that you can have for $100.00, then you could rebuild it and mod it from there with the extra money if ya like, just another option for ya, Just so ya kno, im selling this 305 cuz i put in a LT1... Your choice... if you want the engine or ne questions about it my email is lilc1511@yahoo.com.

 

Thanks for the offer 90formula. I think I'm going to stick w/ the crate engine idea. I figure, it's already built, it's brand new, and should have a longer life span. Just easier on me, since I don't have to mess around building up a used one. You know what I mean?

Anyone know about the fuel issue?

 

yea man i kno exactly what you mean, working with used can be a hassle, and i think you can go a little bigger on the injectors without any problems...

 

where you from? and is it long block or short block?

 

I'm from Minnesota, and it is a short block that i would give up for 100.00, It is in long block form right now though, I was going to use some of the parts from the long block, but if you want the long block i would let the whole thing go... don't really have a price in mind for that, if you want it make an offer

 

i would take if you lived closer i don't have the money for shipping

 

yea shipping on my LT1 was 300.00 and that was with some guyz discount...

 

How hard was your LT1 swap? How much power are you puttin' out w/ everything you've done now? I'm guessing w/ that engine I'm looking at, somewhere around 400rwhp, 420tq (give or take) when everything is said and done.

 

The engine isn't totally in yet, just sitting in there ya kno, and thats obviously easy

 

lol so what your saying is that you haven't played the guessing game for what plug goes where?

 

exactly, it will suckass im sure....

 

With the sdpc engine:
http://www.sdpc2000.com/cart.asp?act...=1577&pid=9009
What would the rwhp be? I was reading a post on the TPI message board:
https://www.thirdgen.org/techbb2/sho...5&pagenumber=1
And all these guys are saying you can't get that type of horse from TPI.
So, this is making me contradict even getting that engine. Would it be a good swap? W/ headers, cat back, etc. etc. what would I be able to push from that engine w/ a stock tpi setup? Like I said, I can get the plenum, tb, etc. etc. for $100 off an 87 IROC. I'd also go w/ Edelbrock Runneres most likely.
So, what's the bottom line you think?
Oh yeah, and I would transfer the power w/ a Pro Built Street/Strip 700R4 w/ the Vigilante Torque Converter.
Give me some good news guys!! lol

Thanks

 

sweetride, im right in chicago too. i have a rebuilt lg4 305 out of a 92 bird sitting in my garage. it has about 25k-30k miles on the rebuild and ran really well when i pulled it. it was a tbi motor and is complete intake to pan. i gotta make some room in my garage. ill let it go for 400.

lemme know if your interested.
-jeff