1/12 Trumpeter vs Meng engine size?

I have both a Trumpeter 1/12 GT40 kit and the Meng Engine sprues and there is a significant difference in the size of the engine/transmission. The Trumpeter engine block is about 1/8" smaller in length. The whole engine is smaller all over.
The figures I’ve found for just the block size on-line actually seem to show both are small.
Anyone ever measure either engine to see which is more accurate? I think I can mount the Meng engine block in the Trumpeter frame using the Trumpeter transmission to get the rear suspension to mount.
Very odd that the engine and transmission for the same car aren’t the same size. I wonder if Trumpeter used a GT40 MkII that had a smaller engine installed

For what it’s worth, the Gt40 Mk I was powered by the same basic 289 ci 5 liter engine that came from the Mustang engine line up. The Mk II’s all had the 427 ci 7 liter engine that I believe started life out from the Nascar engine program. I’m sure that if you did a few google searches you can find the exact block dimensions.


Using the few listed “block” measurements for the 427 FE motor
That’s where it kind of “comes off the rails”
Using the cylinder to cylinder spacing both are close. The crankshaft centerline to block deck the Trumpeter is definitely small, but the Meng is a bit off as well
If the Meng is overall closer, you still cannot use the complete engine and transmission in the Trumpeter chassis. It is too long.
While I think the Meng engine captures the hulking look of the 427, the Meng transmission looks oversized.
I couldn’t find the dimensions for the transmission/transaxle to compare
Not sure how both kits have the major car dimensions correct but have the engine/transmission so different

The Meng kit is much newer and has been receiving positive reviews just about everywhere. The Trumpeter kit isn’t exactly a youngster any more and was designed within the standards of the day.
I have no idea if the Meng kit started with laser scanning the car, interior, engine, etc, it’s a no brainer that the Trumpeter kit was done strictly by hand… Who knows if a measurement or two was incorrectly taken, or if ithe Transmission measurements were changed so that the the entire power train fit the chassis/body.
If you have the Meng engine, why not use the entire kit?

Just have the engine & transaxle sprues. I bought them to add some detail to the Trumpeter kit
Silly me, I thought 1/12 would be the same
I am not convinced that the Meng kit is worth its selling price. And the way it is engineered has caused a fair amount of errors - okay in a $100 kit, not a $300+ kit
I decided not to spend the $50 a 3d printed 1/12 Ford 427 motor kit costs. I will see if the Meng block will fit and go from there

Good luck with the engine swap. Sure hope that you can shoe horn it in and get the transmission and transaxle to fix correctly.


I finally found a fairly succinct listing of the major engine block measurements for the Ford FE series of engines
The one issue is that several GT40 MKIIs have been re-engined using newer Ford motors

According to the Ford information, all Ford FE engines are Y-block designs
From 332 to 428, the block was the same
The block extends 3.625" (92.1mm) below the crankshaft journals
The FE blocks have a 4.630" (117.6mm) bore spacing and a deck height (crank center to top of the block) of 10.170" 258.3mm).

Dividing by 12 for 1/12 scale gives the following
Casing extension - .30"
Bore spacing - .385"
Deck height - .85"
Dig out you calipers

The closest fractional sizes are
Casing - 5/16" (.313")
Bore Spacing - 3/8" (.375") (less than 1/64" difference)
Deck height - 3/4" (.75") (less than 1/10" difference)

Time to see the actual differences between the two models.

I wonder if Trumpeter actually used a GT-40 MKII that either had a newer 427 (the blocks are smaller) or one that had been re-engined with the 302 Windsor based engine used in the GT-40s’ later years, very similar engine just smaller all the way around.

Now that’s really interesting. The 289 ci series is referred to as a small block while the 427 ci engines were referred to as a big block. Stroke and bore does indeed increase the ci of a engine, but not sure if can be stretched that much. The Ford 289 and 427 engines are different in size from what I’ve read.
I do remember visually seeing at the shop way back in the 1970s a 289 cobra and a 427 Cobra. The 427 needed to be shoe horned into the engine compartment while the 289 left room to spare.
While driving myself crazy trying to learn and track down the correct colors, I’ve learned that many of the original GT40 Mk IIs that still exist today have had parts, engine, transmission, and transaxle changed depending on what the owner goal for the car was. Many raced them in Historical events and they became more of a kit car then a true Replicar.
I’d just find the best fitting engine and go with it at this point.


The original 427’s were called FE side oilers. The design started with 330 Cubic Inches and eventually reached 428 Cubic Inches.
This was the large Ford engine found in the Galaxies of the 1960’s
Later Ford 427’s used a different, and smaller, block design.
The “original” “Small-Block” Ford engines are often called “Windsor” models.
The GT-40 Mk1 used the 289 small lock - eventually enlarged to 302 CI.

About the models - Neither got it right. Trumpeter appears to have the best overall dimension relationships - it’s just too small, like 90%. The plumbing around the engine and engine compartment is either made up, or overly simplified.
Meng’s engine block is the right size, but the dimensions are off. The transaxle also seems too large. Meng’s plumbing has its own issues as well, plus the oil lines are smooth, not the braided ones used. Some are just wrong.
I used a 3D 427 FE block kit from 3D Specialties to rebuild the engine. Meng really missed some of the unique details of the blocks used on the G-40 427 motors - the heads are not correct and with the plug wires, it shows.
Both companies totally missed the correct oil hose plumbing. Trumpeter has a part - E17 - mounted in the lower engine compartment and painted orange. Nothing connected, but there.
Looking at the photos on RK Motors site of the restoration of the #2 LeMans car, there are pictures of the lower engine compartment, and one of the 427 being tested which shows alot of the missing details of the oil system. The orange “can” in the compartment, that was the oil filter.
Trumpeter has a part - H3 - that connects two lower connection to the water pipe. In reality these were where the oil lines from the front oil reservoir attached. Lines came out an adapter on the block that ran to the oil filter and the to the base of the cooler and back.
RK motors also has photos of the actual oil lines to the transaxle - both companies are wrong, although Trumpeter is less wrong.
RK has color photos that are great because they restored the car to its LeMans configuration.
If I can find basic photos that show where oil lines run in and around the engine compartment, why could neither Trumpeter nor Meng do it as well. I’m glad I bought the Trumpeter kit - at least I wasn’t gouged on the price. Even with the extra parts and motor, it still is far less than the Meng kit costs.

I’ve almost got a reasonable facsimile of the actual 427 engine used in the GT-40 Mk2
The block, heads, and covers are from 3D Model Specialties
The external bits and pieces are from both Meng & Trumpeter
I’m still trying to figure out the correct oil lines - Trumpeter just had them “disappear” and Meng got most wrong.
RK Motors restores the #2 car -chassis #P1046 and has some great pictures of the engine compartment without the engine and the motor on a testing stand with the various oil lines attached.
One thing that it appears every GT40 MKII model missed is that there is no oil filter on the block.

I know this may seem a bit OCD but considering the cost of the kit, these models are nowhere near the level of detail of the 1/12 Tamiya F1 cars. If I could find out the issues with the engine and the engine compartment just researching online, what cars did either Trumpeter or Meng actually use to design the kits?