Outer Limits 4x4 Board

Hello all,

My tb42 has done another head and the engines lower end is well worn as well so I'm looking at my options regarding engine transplants.

I have a impco gas system (mixer on carbie) which I would like to keep with minimal modification for the new motor. The chev 350 seems to be a common swap with the adaptors readily available from the likes of Marks Adaptors and a brand new crate engine is affordable. This engine with a 5-speed trans should give me many years of trouble free 4wding.


What I would like from you is the benifit of your experience/opinion regarding the suitability of the engine to 4wd application. For example:
1. Is the torque curve of the engine low enough in the rev range for crawling steep rock?
2. Does the chev suit gas without head/valve modification?
3. Do the chevs run properly with the comprimise tune required for dual fuel or do you have to go straight gas?
3. Being a 5.7ltr, what sort of economy figure are you getting (gas & petrol)?

Any other experiences you have regarding these motors in 4wd's would be appreciated. I want to make the right decision first time.

Cheers Mex

350 has plenty of low down torque that continues up the revs very smooth. it will run good on gas and petrol, but it will run better on one or the other. and like nearly every engine for best life stainless valves and shit need to be done. but itll run for some time without anything, how long is up to the engine.


3rd gear uphill burnouts are very possible, just as an indication of the power.

if some one has contradiction to this please teach me

MEX wrote:Hello all,

My tb42 has done another head and the engines lower end is well worn as well so I'm looking at my options regarding engine transplants.

I have a impco gas system (mixer on carbie) which I would like to keep with minimal modification for the new motor. The chev 350 seems to be a common swap with the adaptors readily available from the likes of Marks Adaptors and a brand new crate engine is affordable. This engine with a 5-speed trans should give me many years of trouble free 4wding.


What I would like from you is the benifit of your experience/opinion regarding the suitability of the engine to 4wd application. For example:
1. Is the torque curve of the engine low enough in the rev range for crawling steep rock?
2. Does the chev suit gas without head/valve modification?
3. Do the chevs run properly with the comprimise tune required for dual fuel or do you have to go straight gas?
3. Being a 5.7ltr, what sort of economy figure are you getting (gas & petrol)?

Any other experiences you have regarding these motors in 4wd's would be appreciated. I want to make the right decision first time.

Cheers Mex

you cant go wrong

excellent power
better econmy
good reliability
excellent on LPG even with dual fuel
if you get a unleaded chev, you wont have valve seat problems or valve problems, early heads are very strong and they even last .

things you should do to your chev.

1 try and get a late model one( unleaded) which will also have good mounts for power steer and ac
1.5 at least LEAST 10.5:1 compression
2 electronic ignition is a must ( read MUST)
3 speadbore holley or quadrajet for carby ( quad is better offroad)
3 gas cam
4 aftermarket intake manifold, single plane edlebrock
5 get the large flywheel for increased MASS which adds low end torque ( not that you need it)
6 larger capacity sump

the impco 300a you more than likely have now is ok, and will give you better low down torque, but a 425 works better allround with the 350.

with this setup, you will get excellent power, unbeleivable reliability, and excellent economy to boot UNDER NORMAL DRIVING CONDITIONS( the economy)

because if you drive with your foot flat to the floor or course 350 cubes are gona chew more than 250


Cheers,
Jes

gday mate

for the low down torque, a couple extra dollars would get ur 350 into a 383. had one in my kingswood. at 10.5:1 comp i found that premium unleaded had trouble making the car run smoothly, and that straight gas works well at that compression. concerning the head, i had a set of 624 heads which r the newer version of the old 882 head, i think from memory they cost about 700 bucks new (this was a few years ago). for 1400 i had the option of going to the corvette alloy heads with the roller bearings and all the wizz bang, but i dont know how they would cope with the heat from constant low gear/high rev application when fourbying though. another thing to consider is the type of radiator when u put a larger capacity engine into the car. i found that the falcon thermo fan setup is easily modified to fit onto standard triple core 350 chev radiators. other thing was as jessie said, plenty of right boot and u will discover just how thirsty 350+ cubes can be. i got 180km's per 80l's around town! as a rule of thumb with a good engine, one cubic inch should equal one horsepower or more. my basic 383 had around 450 horses with minimal mods. (think the 650 double pumper helped too though )

i miss my chevy

cheers
Leayton

Carchania wrote:gday mate

for the low down torque, a couple extra dollars would get ur 350 into a 383. had one in my kingswood. at 10.5:1 comp i found that premium unleaded had trouble making the car run smoothly, and that straight gas works well at that compression. concerning the head, i had a set of 624 heads which r the newer version of the old 882 head, i think from memory they cost about 700 bucks new (this was a few years ago). for 1400 i had the option of going to the corvette alloy heads with the roller bearings and all the wizz bang, but i dont know how they would cope with the heat from constant low gear/high rev application when fourbying though. another thing to consider is the type of radiator when u put a larger capacity engine into the car. i found that the falcon thermo fan setup is easily modified to fit onto standard triple core 350 chev radiators. other thing was as jessie said, plenty of right boot and u will discover just how thirsty 350+ cubes can be. i got 180km's per 80l's around town! as a rule of thumb with a good engine, one cubic inch should equal one horsepower or more. my basic 383 had around 450 horses with minimal mods. (think the 650 double pumper helped too though )

i miss my chevy

cheers
Leayton

yeah a 383 wil suck gobs more juice than a 350

but you will find that a 400 small block is much better suited to a truck than a 383

You need low down torque to push the brick through the air at highway speeds ( especially if you have lift and big rubber). fir instance torque needs to be on tap at about 1800rpm.

Jes

MEX wrote:Hello all,

My tb42 has done another head and the engines lower end is well worn as well so I'm looking at my options regarding engine transplants.

I have a impco gas system (mixer on carbie) which I would like to keep with minimal modification for the new motor. The chev 350 seems to be a common swap with the adaptors readily available from the likes of Marks Adaptors and a brand new crate engine is affordable. This engine with a 5-speed trans should give me many years of trouble free 4wding.


What I would like from you is the benifit of your experience/opinion regarding the suitability of the engine to 4wd application. For example:
1. Is the torque curve of the engine low enough in the rev range for crawling steep rock?
2. Does the chev suit gas without head/valve modification?
3. Do the chevs run properly with the comprimise tune required for dual fuel or do you have to go straight gas?
3. Being a 5.7ltr, what sort of economy figure are you getting (gas & petrol)?

Any other experiences you have regarding these motors in 4wd's would be appreciated. I want to make the right decision first time.

Cheers Mex

jessie928 wrote:
you cant go wrong

excellent power
better econmy
good reliability
excellent on LPG even with dual fuel
if you get a unleaded chev, you wont have valve seat problems or valve problems, early heads are very strong and they even last .

things you should do to your chev.

1 try and get a late model one( unleaded) which will also have good mounts for power steer and ac
1.5 at least LEAST 10.5:1 compression
2 electronic ignition is a must ( read MUST)
3 speadbore holley or quadrajet for carby ( quad is better offroad)
3 gas cam
4 aftermarket intake manifold, single plane edlebrock
5 get the large flywheel for increased MASS which adds low end torque ( not that you need it)
6 larger capacity sump

the impco 300a you more than likely have now is ok, and will give you better low down torque, but a 425 works better allround with the 350.

with this setup, you will get excellent power, unbeleivable reliability, and excellent economy to boot UNDER NORMAL DRIVING CONDITIONS( the economy)

because if you drive with your foot flat to the floor or course 350 cubes are gona chew more than 250


Cheers,
Jes

X2

ITS ONLY A MATTER OF TIME AND I'M THERE TOOOOOOOOOOOOOO

AS ABOVE

MEX wrote:Hello all,

My tb42 has done another head and the engines lower end is well worn as well so I'm looking at my options regarding engine transplants.

I have a impco gas system (mixer on carbie) which I would like to keep with minimal modification for the new motor. The chev 350 seems to be a common swap with the adaptors readily available from the likes of Marks Adaptors and a brand new crate engine is affordable. This engine with a 5-speed trans should give me many years of trouble free 4wding.


What I would like from you is the benifit of your experience/opinion regarding the suitability of the engine to 4wd application. For example:
1. Is the torque curve of the engine low enough in the rev range for crawling steep rock?
2. Does the chev suit gas without head/valve modification?
3. Do the chevs run properly with the comprimise tune required for dual fuel or do you have to go straight gas?
3. Being a 5.7ltr, what sort of economy figure are you getting (gas & petrol)?

Any other experiences you have regarding these motors in 4wd's would be appreciated. I want to make the right decision first time.

Cheers Mex

Ok ive done this conversion, i bought a brand new vortec 350, marine combo which delivers outstanding low down torque and pulls hard through the whole rev range.Mine makes max torque at 1370rpm of 460Nm and pulls strong all the way.I use a NEW GEN gas mixer which bolts onto the Rochester carby and that works great.Economy on gas is ok, for 88 litres around town i get 360K's driving 33's.On petrol from 60 litres i get about 250 k's but i tend to drive it hard on petrol so its probably not a fair comparison.

As for mods for gas etc,i use a flashlube system and so far (50,000k's) haven't had any issues whatsoever.There is no need for a compromised tune , you should run the timing more advanced for gas with the advance weights being setup to come in early but this will only effect petrol if you dont run premium.

I used a marks adapters kit and found it too be excellent, i have just trialled a set of there rebuildable engine mounts for a few weeks, now they are strong but very harsh ,you feel every little engine vibration so unless you are competeting or towing all the time i would suggest just using the std ones that come with the kit.

I bought my motor from suburban inports, the motor was fine BUT they supplied me with a flywheel that was incorrectly balanced for the VORTEC so i have just had the engine out again to have it re-balanced (at my expense i might add) cause i just new that it wasn't right,it just wasnt as smooth as i thought it should be and it turned out it was 50 grams out so just be wary.Now its SWEET.Gary is happy to take your money but dont ask for any after sales service or help he is F%^&ing useless.

Anyway enough from me, get that engine out and get into it.If you need any more help or tips let me know.

Matt

Thanks for the info everybody. I'm sure I'll have more questions as I go along.

I recently picked up a crate motor from eagle auto. 350chev with manifold, electronic dizzy, leads, plugs, etc for jus over 2k. Am running it on lpg and is running in sweet.

madrolla68 wrote:

MEX wrote:Hello all,

My tb42 has done another head and the engines lower end is well worn as well so I'm looking at my options regarding engine transplants.

I have a impco gas system (mixer on carbie) which I would like to keep with minimal modification for the new motor. The chev 350 seems to be a common swap with the adaptors readily available from the likes of Marks Adaptors and a brand new crate engine is affordable. This engine with a 5-speed trans should give me many years of trouble free 4wding.


What I would like from you is the benifit of your experience/opinion regarding the suitability of the engine to 4wd application. For example:
1. Is the torque curve of the engine low enough in the rev range for crawling steep rock?
2. Does the chev suit gas without head/valve modification?
3. Do the chevs run properly with the comprimise tune required for dual fuel or do you have to go straight gas?
3. Being a 5.7ltr, what sort of economy figure are you getting (gas & petrol)?

Any other experiences you have regarding these motors in 4wd's would be appreciated. I want to make the right decision first time.

Cheers Mex

Ok ive done this conversion, i bought a brand new vortec 350, marine combo which delivers outstanding low down torque and pulls hard through the whole rev range.Mine makes max torque at 1370rpm of 460Nm and pulls strong all the way.I use a NEW GEN gas mixer which bolts onto the Rochester carby and that works great.Economy on gas is ok, for 88 litres around town i get 360K's driving 33's.On petrol from 60 litres i get about 250 k's but i tend to drive it hard on petrol so its probably not a fair comparison.

As for mods for gas etc,i use a flashlube system and so far (50,000k's) haven't had any issues whatsoever.There is no need for a compromised tune , you should run the timing more advanced for gas with the advance weights being setup to come in early but this will only effect petrol if you dont run premium.

I used a marks adapters kit and found it too be excellent, i have just trialled a set of there rebuildable engine mounts for a few weeks, now they are strong but very harsh ,you feel every little engine vibration so unless you are competeting or towing all the time i would suggest just using the std ones that come with the kit.

I bought my motor from suburban inports, the motor was fine BUT they supplied me with a flywheel that was incorrectly balanced for the VORTEC so i have just had the engine out again to have it re-balanced (at my expense i might add) cause i just new that it wasn't right,it just wasnt as smooth as i thought it should be and it turned out it was 50 grams out so just be wary.Now its SWEET.Gary is happy to take your money but dont ask for any after sales service or help he is F%^&ing useless.

Anyway enough from me, get that engine out and get into it.If you need any more help or tips let me know.

Matt

marine cam is a great idea. good holeshot..eheheheheh


Jes

Try and PM ohshi
He has a super charged 350 in his Patrol and is swapping it out this week for another that is fuel injected.
He may be able to help out with some thoughts.

Do the Vortec engines meet emmisions standards for EFI patrols, was looking at at a gen3 but might be swayed

run it on gas problem solved can always put a carby back on later

offroader-rama wrote:run it on gas problem solved can always put a carby back on later

Mines a late 1991, was carby 4.2 and its now licensed for petrol/gas with rochester.

No-one said anything about it when i took it to be licensed.

thats because it was carby all ready they dont like you going from efi back to carby i do not see the logic whats the difference exept the mechanics bill (and in some cases economy) but thats the owners choice makes no difference to pollution IMHO!!!

f@#k the gen III to many problems to much electrics to much bolt on sh#t patrols are hard enough to reach into to fix as it is let along putting that anchor in there well mine is any way. a 383 stroker straight gas, elect dizzy, a modest 420hp+, 480 lbs+, at 5000rpm all day, every day, for ever full stop,( dont quote me on forever, conditions apply ) only maintence is check gas flow, timing and oil. same economy as the 4.2 it replaced.

dont tell me the gen III is better due to its no maitainance efi computer bullsh#t where talking play in mud, crush those rocks lots of dry joints 4wd here, you dont want that shit to go wrong, where racq cant go and it aint going to be cheaper to run there is 2 ton of a brick its pulling around.
in a torana different story but in a truck that is lucky to see 150kph due to areo dynamics,gearing, and handling why go so high tech.

sorry to borst your bubble or you might have a different opionion or need

MY 2C anyway, but i am byast

Sad001, give me an email addy and I'll send you heaps of info on the Vortec. When fitted to the trucks, all were efi. Only the crate ones come with a carb. But my usual LPG bloke said that if the engine originaly had a O2 sensor it needs to have one again, which is done with LPG. Straigh LPG or not. V8Patrol may confirm this.

Incoming

BowTieGQ wrote:Sad001, give me an email addy and I'll send you heaps of info on the Vortec. When fitted to the trucks, all were efi. Only the crate ones come with a carb. But my usual LPG bloke said that if the engine originaly had a O2 sensor it needs to have one again, which is done with LPG. Straigh LPG or not. V8Patrol may confirm this.

This was not required here in WA,so not sure about you guys.

Gen 4 6,0 Litre out of VE seems to be cheap at the moment through CRUSHU off here.

I've been talking to an engineer & queensland transport regarding the 350 swap and if I'm to keep it dual fuel I will need to pass the IM240 emissions test. Have any of you had to pass this and if so what did you require (cat ?). Remamber this is a carby engine.

Cheers Ian