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GM 3.4L V6: Recipe for 200HP?

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BFC Avatar
BFC Ben Clark
Allegan, MI, USA   USA
1980 MG MGB "Kilr B"
1980 MG MGB MkIV
My stock 1800 engine is doing things I don't like and may need to get pulled, costing me most of my summer driving, so I am looking into installing a GM 3.4L V6 rather than sink more time into the stock engine.

I live near Gingerman Raceway and would like to take the car out for various track days in addition to it being a summer daily driver. Looking over the power/weight ratios of various cars, I think I'd like to get the new engine up to 200HP or more. I know HP isn't everything, but at 200HP both the power/weight ratio and the torque numbers would be good enough to avoid getting "pantsed" by more modern cars. Also, let's assume that I am talking about 200bhp not whp, as the stock engine is 160bhp.

What I am looking for is a basic "parts recipe" that will get some extra power from the V6. On the ClassicConversions web site, the best HP numbers they get are from a carburated engine:

GM Chevrolet 3.4 crate engine with Edelbrock manifold and #8007 Holley 390cfm carb, 1 1/2 headers and 1.6 ratio crane roller rocker arms
Power Output: 220 hp @ 5000 rpm
Torque: 210 lb @ 2700 rpm

That's a pretty good recipe. Except that I don't see the 3.4L V6 listed on Chevy's Performance web site and the ones from Summit are for the later FWD cars, so I'd probably be starting with a stock used/rebuilt Camaro V6. I assume that the crate engine has a hotter cam than the stock ones? I don't know.

I am open to anything - running the stock FI and ECU, using a different FI system and a Megasquirt ECU , carburation setup, with the following caveats:

--As long as none of the instructions tell me that I need to design/fabricate stuff or do any serious welding. My welding-fu is pretty terrible and my crummy Harbor Freight drill press may let me do some machine work, but not much.

--I know that the Ford 302 and BOPR folks out there will tell me that I should use their engine as an easier way to get 200HP, but for now, lets stick to the GM 3.4 V6. Specifically, the RWD variants.

-- And finally, if I am wrong and a 160HP/187lb/ft is plenty to compete against Toyota 86s, Subaru WRX STIs, and various Mustangs, let me know. I'll save time and money and not bother with upgrading the engine. grinning smiley



I don't know. It's always smoked like that/made that sound/done that.

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Townsend, TN, USA   USA
Ben -

Unfortunately, GM discontinued production of the crate 3.4. I happened to get mine just before that happened. I have the same setup as Bill's, but without the roller rockers, but have no idea of power output. All I know is that it's plenty for my tastes.

Mickey

Edit: Oh, and I was told that the crate engine's cam has pretty much the same profile as the FI cam.



'73 MGB
'69 MGB GT/V6 Conversion
Victor TF



Edited 1 time(s). Last edit at 2018-06-04 09:47 AM by Mickey Richaud.

GWHITE75 Avatar
GWHITE75 Gold Member Gary White
Sugar Land, TX, USA   USA
1973 MG MGB "OldBlue#2"
1975 Chevrolet Corvette Stingray "Old Red"
2006 Chevrolet Corvette "OldBlue"
Thanks for throwing your situation and concerns out there Ben, as I too, wondered how that 3.4 made 220hp, but didn’t follow up with inquires about it. I have just pulled out my tired 3.8l Buick motor and will tear it down today to see if it can be rebuilt, but have not closed the door on a 3.4, if I can find a ‘reputable’ company that sells remanufactured engines. My preference is to go the carbureted route and if I can get a recipe for 220hp, then most likely make the switch. No V8, no power adders.

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ohlord Avatar
ohlord Gold Member Rob C
North of Seattle, N.W., USA   USA
1957 Land Rover Series I "EYEYIYI"
1971 MG MGB
1971 MG MGB "Bedouin 2"
Takes very little for 200hp

Why not rebuild your own v6?



"I'm a long way gone down this wild road I'm on
It's gonna take me where I'm bound
It's a long way around"



"These are the days that must happen to you"

RD2 Radar/ Electronic Warfare Technician
Vietnam 1969-1972


Attachments:
Old Blue 275H.P. V6 swap sidepipe nascar exhaust rear profile.JPG    40.6 KB
Old Blue 275H.P. V6 swap sidepipe nascar exhaust  rear profile.JPG

jewar Avatar
jewar Silver Member John Warlimont
Abbotsford, BC, Canada   CAN
Yesterday at a car show, Bil Sinclair of British Car conversions was there with a friend and 2 cars, a 3400 MGA and a 3500GM in a Triumph TR6 the 3500 I believe is 220hp SFI. Nice replacement for a 3.4



https://www.britishcarconversions.com/

JOhn

BFC Avatar
BFC Ben Clark
Allegan, MI, USA   USA
1980 MG MGB "Kilr B"
1980 MG MGB MkIV
The question being, what is the "very little" that it takes?

I may end up building my own V6. It depends on time and money. Accurate Engines is near me in Grand Rapids and does engine rebuilding nationally, so I might just buy a core from them if I can't find anything used that's close, cheap or good. In either case, I need to know what parts I'd customize it with.

In reply to # 3749360 by ohlord Takes very little for 200hp

Why not rebuild your own v6?



I don't know. It's always smoked like that/made that sound/done that.

BFC Avatar
BFC Ben Clark
Allegan, MI, USA   USA
1980 MG MGB "Kilr B"
1980 MG MGB MkIV
John-
That's funny, because I, too, was at a car show yesterday (The British Return to Fort Meigs, near scenic Toledo, OH) and talked at length with a guy who'd used a 3500 GM engine in his conversion. He said if he had to do it again he'd use a 3.4 and the CCE kit because he spent too much time and effort on fabbing his own mounts and dealing with transmission mate-up issues. He did a superlative job and the car looked great, but it was interesting to hear an experienced machinist say he'd go an easier route next time.

In reply to # 3749367 by jewar Yesterday at a car show, Bil Sinclair of British Car conversions was there with a friend and 2 cars, a 3400 MGA and a 3500GM in a Triumph TR6 the 3500 I believe is 220hp SFI. Nice replacement for a 3.4



https://www.britishcarconversions.com/

JOhn



I don't know. It's always smoked like that/made that sound/done that.

scott68B Avatar
scott68B Scott Costanzo
Central, OH, USA   USA
1968 MG MGB "GM 5.3 LS4 V8"
I'm planning on visiting Kelowna this fall and hope to stop by Bill's shop for a look. If you're going with a V6, this is the way to go.

In reply to # 3749367 by jewar Yesterday at a car show, Bil Sinclair of British Car conversions was there with a friend and 2 cars, a 3400 MGA and a 3500GM in a Triumph TR6 the 3500 I believe is 220hp SFI. Nice replacement for a 3.4



https://www.britishcarconversions.com/

JOhn

GWHITE75 Avatar
GWHITE75 Gold Member Gary White
Sugar Land, TX, USA   USA
1973 MG MGB "OldBlue#2"
1975 Chevrolet Corvette Stingray "Old Red"
2006 Chevrolet Corvette "OldBlue"
In reply to # 3749374 by BFC
He said if he had to do it again he'd use a 3.4 and the CCE kit because he spent too much time and effort on fabbing his own mounts and dealing with transmission mate-up issues. He did a superlative job and the car looked great, but it was interesting to hear an experienced machinist say he'd go an easier route next time.

My concern as well and the reason I’m looking at the 3.4l. BMC and Bill Guzman have the parts ready to make a conversion easier. That being said, I may just rebuild mine, if it isn’t too worn out (bored .040) to get it back on the street, but would like a newer vintage engine capable of more HP without turbos/superchargers. I’m also interested in the 4cyl transplants being done now, by ‘OHLORD’ and others, even though I know they need the turbo to get 200+ hp and not an easy conversion.

scotabbott Avatar
scotabbott Scot Abbott
Pittsburgh, Pa 15216, USA   USA
1974 MG MGB "Bee"
*****************Foreword/warning : I am opinionated and lean toward making things in a simple, economic way, rather than just 'throw money' at things. **************


I love the 60 degree RWD GMV6 conversion route. I've done a number of them-even made my own alternator and motor mounts (see my journals on this site)-. They are a nice install and produce a solid performing car without a lot of hassle. I personally do them with fuel injection, although I did one with carbs at first. EFI is just so much better and not magic.
The motors are very reliable (I've seen many with more than 200k miles.), and it makes me wonder about needing to rebuild a used engine if it has less than 100K on it. A look at the top and bottom end can tell the whole story.

260mgb Jim Nichols
Sequim,WA, USA   USA
For performance on 3.4 V6 this is the place:
http://www.engine-parts.com/gmv6/28camspecs.html

V8MGBV8 Avatar
V8MGBV8 Carl Floyd
Kingsport, TN, USA   USA
Like Mickey mentioned the GM 3.4L crate engine was discontinued 8 or 9 years ago. There were some available in inventory for a few more years.

Don't confuse flywheel rated HP with rear wheel HP. I don't see getting 220hp to the wheels with a carb & cam & the stock heads.

GWHITE75 Avatar
GWHITE75 Gold Member Gary White
Sugar Land, TX, USA   USA
1973 MG MGB "OldBlue#2"
1975 Chevrolet Corvette Stingray "Old Red"
2006 Chevrolet Corvette "OldBlue"
In reply to # 3749402 by 260mgb For performance on 3.4 V6 this is the place:
http://www.engine-parts.com/gmv6/28camspecs.html

Good stuff Jim. I’ve looked at that site before. They actually stroke a 2.8 to 3.1 or 3.4l. Prices seem reasonable, but do you know people who’ve used them?

260mgb Jim Nichols
Sequim,WA, USA   USA
I got cam kits from them years ago.

BFC Avatar
BFC Ben Clark
Allegan, MI, USA   USA
1980 MG MGB "Kilr B"
1980 MG MGB MkIV
I checked out the British Car Conversions web site a few days ago.
1) There's no mention of MG anywhere on their site. The home page says "TRIUMPH" in all caps and bold letters.
2) The descriptions on the kits themselves are so short that I have no idea what cars they would fit. Here is the full text on one of the kits offered:
E KIT INSTALL
989.00
COMES AS PICTURED
EK 3.4L CAMERO EK 3400/3500 LX9

What cars does this go into? No idea. I am sure Bill Sinclair is awesome, but there is simply not enough information on the BCC web site that I can begin to make an informed decision. Thus, I had to rule out the 3x00 engines, even though they would make the horsepower I am looking for without any mods.


In reply to # 3749381 by scott68B I'm planning on visiting Kelowna this fall and hope to stop by Bill's shop for a look. If you're going with a V6, this is the way to go.

In reply to # 3749367 by jewar Yesterday at a car show, Bil Sinclair of British Car conversions was there with a friend and 2 cars, a 3400 MGA and a 3500GM in a Triumph TR6 the 3500 I believe is 220hp SFI. Nice replacement for a 3.4



https://www.britishcarconversions.com/

JOhn



I don't know. It's always smoked like that/made that sound/done that.

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