LS4 Into an MGB

[mgb260]

Scott, Looks like  time to look at heat/air under the dash.

[74ls1tr6]

Hi Scott,

I'm kind of right there where you are at cutting the fire wall out. On the passenger side head, it does sit father back on that side than the driver side. How much room do you have there with what you cut out already? I noticed you cut out some of the center section out. What measurement did you leave yourself from the head to the center section?? So far I just cut straight off that shelf along side where the head goes, but I do have a 71 which may have more room. I did move my radiator all the way up to the cross section up front. I'm using a 24"wide x 19" tall radiator. So I also cut into the frame rail all the way out to the inner fender. Welded a c channel back in to reinforce the area.

Bought a HF plasma cutter....should have had one along time ago!!! Cut for engine clearance and cut for Vintage Air clearance in about an hours worth of work. It would have taken me days to a week to cut out what I did with a mini grinding wheel or Saw's all.

Looking good Scott !!

[Scott Costanzo]

Hi Calvin,

I was wondering where you were with your B. I'm leaving myself about a 1/4" between the motor and the firewall. I'm cutting the minimum into the firewall and I'm following the contours of the engine which is why part of the heater plenum is still there. Your 71 and my 68 should be exactly the same at the firewall/transmission tunnel. Outside of some touch up I'm done with my trimming except for by the #8 spark plug. What are you doing there?

Sounds like you're making some great progress too. The plasma cutter sounds great...I would have to be careful to not get carried away with it.

Say hi to Brenda

Scott

[rficalora]

RE: Bought a HF plasma cutter....

I told you they are cool.  Still wish i hadnt sold mine, but needed the money at the time.

Calvin - are you using an LS4 too?

[BMC]

Further changes to the firewall were needed to get the engine where I wanted it. The most significant change was to the heater shelf. I wasn't really concerned with maintaining the original heater box but I believe I can modify it to fit.


After reading that I wanted to report you to the moderator but then realized he is on your side. Herumph. I guess this is not a Purist site.

On a more serious note, I have been following your progress with great admiration.

Do you have a photo of the pulleys and how much clearance you have between those and the steering rack and if that was at firewall cutout #1 or the second firewall trim? Without seeing the front, I can't quite tell how the rear trimmed out fits into this equation.

Thanks for keeping us post Scott!

-BMC.

[Scott Costanzo]

Brian,
I don't have a photo of my current pulley clearance but I'll get plenty once things are in place. For cutout #1 I had just enough room to fit the engine between the firewall and the steering rack. There wasn't enough room to tilt it at that point. The second trimming allowed me to tilt the engine into the proper position. I'm aiming for just enough room between the rack and the front pulley to allow a belt to be slipped through in case it needs replacing so that will be about 3/16" give or take. I also had to allow for the bellhousing at the upper two bolts. The bellhousing is an inch thick in that area not counting the two bolt heads. That is why you see the heater plenum cut out the way it is. I am going to rebuild the plenum when I put the firewall back together so much of what you see missing will be replaced. Hope this answered your question.

Scott

[74ls1tr6]

Hi Rob,

No I'm using the ls1. Both the ls4 and ls1 are pretty close in size I believe.

[MGBV8]

The crankshaft is 13mm shorter, but the main thing is the accessories are more compact & driven by a single belt to save space. It's a 5.3L vs 5.7L Comes with LS6 heads, though. Lots of upgrade potential

I'm sure Scott has read this several times. I'll stick it here for future reference:

During the research phase, I quickly realized that while 303hp in stock form isn't a slouch, it seemed GM outfitted the LS4 with good heads and compression but with smaller/more restrictive intake and exhaust components than the other RWD LS(x) applications. If it made 303 hp with all these restrictions, I was curious to see what would happen when all these restrictive components are removed/upgraded.

So I spend some time figuring out what was different on the LS4 vs. the RWD LS(x) engines going component by component and compiled the following list of planned performance upgrades:
**LS4 78mm MAF upgraded to 85mm MAF
**LS4 76mm DBW throttle body upgrade to 90mm LS2 DBW throttle body
**LS4 76mm Intake manifold upgraded to 90mm LS2 Intake manifold and matching LS2 fuel rail
**LS4 28lb injectors upgrade to 34lb LS2 injectors (came with the fuel rail)
**LS4 stock camshaft (197/197 .286/.286 @ 114LSA upgraded to a 224/231 .332/.338 @ 113 lsa (some will say this is too big...)
**LS4 stock exhaust manifolds upgraded to LS7 hydro formed exhaust manifolds

These upgrades should do wonders to help the LS4 pump some air and make some power. All these upgrade components except the camshaft were purchased used off LS1tech.com or Ebay to help keep the upgrade costs down, but in total they were still higher than the initial engine purchase.

[mgb260]

Yeah, I have a copy of the dyno chart of that build 380HP.

[MGBV8]

http://www.gmls4.com/

At the wheels, no less!

List of mods:
Car is an 88 Fiero that weighs 2807 lbs.
5.3L LS4 - stock heads and lower end
224/232 New Era DoD camshaft with pushrods/springs
Stock LS2 intake, injectors, Throttle body
Stock LS7 MAF and exhaust manifolds
4" cold air intake
Magnaflow 3" in dual 2.5 out exhaust
2006 Pontiac G6 6 speed manual FWD transmission (F40)
12lb aluminum flywheel
Spec stage 4+ 10" clutch

[mgb260]

He forgot to mention the heavier valve springs that came in the cam kit. Max power at 7000 RPM! It would be beneficial to advance 4 degrees to move power curve down. Plus if he milled the heads .030 for that extra .5 from 10 to 1 stock it would be over 400HP!

[Scott Costanzo]

Yeah, the LS4 has some potential but I should notice a difference going from about 170 hp to the stock 300 hp I would imagine.

Made more progress yesterday. The engine/transmission is in the car at the moment. Still need another day or two to finish the fitting phase. It's amazing how fast the day goes. I spent more than 8 hrs. yesterday and it felt like I was at it for only 3 hrs. Here are a couple of pictures that show how the bellhousing is fitting.







This last one was a quick shot at the end of the day showing the transmission is actually in there. It is tight but it does fit.



Won't have any time to play with the car next weekend but I'm hoping to get a good start on fabricating the motor mounts Thanksgiving week.

Scott

[mgb260]

Scott, I don't know what you have decided on for mounts but, for the 4.9 Cadillac I settled on a LS type adapter plate with solid style SBC upper mount(picture shows rubber mount) and Jeep urethane lower.

[Scott Costanzo]

Jim,
I'm going with the Barry 22000 mounts per a recommendation by Curtis. Specifically, the 22001-14.

I had an unexpected hour to play yesterday so I worked to position the motor a bit more. You can't tell very well from the picture below but the motor is sitting on some temporary "mounts" at the front and I have the transmission cross member in place and supporting the rear. The only place it is touching the body is at a bolt at the rear of the head on the driver's side that I'm using to hold the chain for the hoist. That, of course, will be removed.



The setback is just where I wanted it and it is tilted back about 3 degrees. I think I'm going to lower it maybe 1/8" from where you see it here. There are many details and I'll do a more complete write-up when I'm sure it is in the final position.

[classic conversions]

Is looking good, the only problem I see and it is not a big deal, is the throttle pedal. It is going to be the same issue as the Cobra.

Avoid solid mounts on the aluminum blocks, although the blocks are very strong, a few LS engine mounted solid found themselves with holes in the side of the block at the drag strip seen them.
Use some sort of cushion.

Great work.

[Scott Costanzo]

Played with the car yesterday and made further progress. It's in the tedious phase making sure everything fits right. Replaced the front cross member pads with polyurethane. Also put the starter on to make sure there were no surprises there. As I mentioned before, it is tight but at this point it does fit with no further modification to the firewall. I think one more fitting session should answer the remaining questions about the steering and where the final position of the motor will be. No photos as there really isn't anything new show at this point.

[pspeaks]

I've only owned one Chevy engine in my life and  know nothing of LS engines, but I really enjoy this thread.  I wish more of us had done this, a lot of good information.


Paul

[Scott Costanzo]

Well, got a question answered last night.



This is the steering, FYI.

[billymgb1000]

Here are a couple of pics of my ls1 and the steering shaft

[billymgb1000]

Hello Scott my name is Bill G I did this swap myself last winter I went with a ls1 4.8 I also went with edelbrocks carb conversion I only use the crank and cam sensors my mgb is a chrome bumper early 74 so I had cutting also what I did was to raise the body off the crossmember by 2 inches and made rear shackles 2 inches longer I wanted that stance and look I am not into slamming it to the ground the roads where I live wouldn't allow it anyways I did not want a hood scoop but I had to go with one by raising it I did not have to cut the crossmember up  the steering shaft is a bi%$# but it can be done I noticed someone suggested the block hugger headers that's what I bought I was going to buy the ones you totally build but the tech at jegs said buy the huggers and cut the flange off and reangle it and weld it why weld 15 spots when you can weld 4 instead glad I did that I went with a turbo 350 auto because of 4 back surgeries and a bad left leg I raised the tunnel by one inch worked great I did not have to move the rear cross member just change the mount even the drive shaft is the exact same length I bought new springs all the way around added 2 extra on the rears also traction bars and I made a panhard  back to the steering shaft I had to lift my motor just a little from where I had it and weld 2 flanges on that header just ask me anything you want I will help you any way I can good luck

[BlownMGB-V8]

Honestly I would like to see what it looks like with the engine a little farther forward. I always felt that the straighter the steering shaft the better, and would rather lower the rack than add universal joints.

Jim

[Scott Costanzo]

Bill,

Thanks for the feedback! I'm finding that pictures can be difficult to interpret sometimes but it appears that my engine might be about an inch lower and about an inch further back than you are so I'm going to have to lower my steering shaft about an inch or inch and a half to gain clearance.

Jim,

Thanks for your feedback! Yes, of course I would have preferred to not do any modifications. The steering issue is not unexpected at all. My plans for this project hinge on the motor being positioned where it is in the above picture so that won't be changing. I'll be using another u-joint down by the rack.

Actually had the opportunity to play with the car two nights in a row! Last night I got the motor into position finally. Didn't get any pictures but I'm very pleased with the way it's fitting. Hope to actually start on the mounts this weekend.

Hope everyone has a great Thanksgiving!

[mgb260]

Scott, I kinda like the 2 ujoint steering better because you can rotate the rack or shim to change the angle of the shaft.. You can do the lower ujoint without welding by grinding flats and using 17mm DD Jeep pinch to 3/4" DD lower joint, 3/4"DD shaft to 3/4" 48 spline MGB upper joint.  Plus the aftermarket ujoints are a lot smaller. There is a thread on the Mgexperience board I'll try to find. Found it:          http://www.mgexp.com/phorum/read.php?40,2467295

[Scott Costanzo]

Good advice Jim. I've been looking at the Sweet u-joints as they look very compact. I am currently using a Borgeson u-joint as a direct replacement for the stock u-joint but I like the idea of using a DD shaft in the middle...phasing the two u-joints should be a no brainer and much easier to implement too.

[pspeaks]

Sweet also makes a 3/4"-48 that works on stock MGB steering columns and shafts (401-51010), it's what I used at the firewall.   This is a little unusual but it has been done, Sweet universals can be disassembled like a drive shaft universal and the ends swapped to connect pretty much any kind or size shafts together.  I only mention this to point out there is not much limit to what you can do but for anybody who decides to try this, keep in mind the needles are rather small and the caps can easily be damaged in putting them back together.  The 1" Firewall bearing I used is an actual roller bearing with a rubber seal and is available from Granger (4X730).  Be advised however the stock 1" shaft after being compressed to a DD is no longer 1" and the diameter has to be reduced a few thousands of an inch.  Yes, there are probably much easier ways to do your steering but I liked the way it looked.  



Paul