• Mustang Forums
  • 1974 - 1978 Mustang II Talk & Tech

Yet another v8 swap

  • Thread starter Thread starter dulcimerbob
  • Start date Start date Sep 19, 2026
Prev
  • 1
  • 2
  • 3
  • 4
First Prev 4 of 4

LILCBRA

I wish I didn't have all of these balls in the air
Mod Dude
Dec 6, 2005
6,517
5,512
194
Corn County USA
Thursday at 7:10 PM
#61
  • Thursday at 7:10 PM
  • #61
dulcimerbob said:
Out of stock , Can I use my v6 converter ? the motor I have is maybe 180-200 HP .
Click to expand...

That's a good question, but apparently no. I did a search on using a smaller engine's torque converter behind an 8 cylinder. Apparently it's been done to achieve higher stall speeds. From the Google AI response:

In older vintage applications (like 1970s and 1980s Chevy Vegas), some hot-rodders used a Vega 4-cylinder converter behind a small-block V8 strictly as a budget trick to achieve a high stall speed for drag racing. However, this required specific legacy transmissions (like a Powerglide or early TH350) and was notorious for ballooning or failing under real street-driven V8 power.
 

welder4956

20+ Year Stangneter
Nov 28, 2003
251
116
53
Birmingham, AL
Thursday at 7:26 PM
#62
  • Thursday at 7:26 PM
  • #62
LILCBRA said:
I remember seeing somewhere about the bolt circle being smaller than a standard Ford. It seems like standard Ford converters have a 10-1/2 bolt cirlce whereas the II has a 9-7/8 or 9-3/4 bolt circle. I'll have to search again and see if I can find it - seems like it would be pretty useful, especially right now.
Click to expand...
The official dimension is 9.3 in. bolt circle, which seems to match my tape measure.



 
Reactions: LILCBRA

welder4956

20+ Year Stangneter
Nov 28, 2003
251
116
53
Birmingham, AL
Thursday at 7:29 PM
#63
  • Thursday at 7:29 PM
  • #63
dulcimerbob said:
I messaged the seller and was told they had no info other than the EB description . Big parts house .
Click to expand...
That's the (non)answer I got as well:

 
Reactions: LILCBRA
D

dulcimerbob

Member
Aug 25, 2026
31
23
18
GA
Thursday at 7:54 PM
#64
  • Thursday at 7:54 PM
  • #64
LILCBRA said:
That's a good question, but apparently no. I did a search on using a smaller engine's torque converter behind an 8 cylinder. Apparently it's been done to achieve higher stall speeds. From the Google AI response:

In older vintage applications (like 1970s and 1980s Chevy Vegas), some hot-rodders used a Vega 4-cylinder converter behind a small-block V8 strictly as a budget trick to achieve a high stall speed for drag racing. However, this required specific legacy transmissions (like a Powerglide or early TH350) and was notorious for ballooning or failing under real street-driven V8 power.
Click to expand...
Seems I'm out of luck on the TC . I can't see 600 and up for performance converter . Not sure what to do except go to the 10 3/4 157 flex and a hammer . thanks
 

Blackhawkxx

Mustang Master
Mar 3, 2023
545
533
103
Thursday at 8:25 PM
#65
  • Thursday at 8:25 PM
  • #65
Or put a manual trans in it.
 
Reactions: 2Blue2 and LILCBRA

welder4956

20+ Year Stangneter
Nov 28, 2003
251
116
53
Birmingham, AL
Thursday at 11:41 PM
#66
  • Thursday at 11:41 PM
  • #66
dulcimerbob said:
Seems I'm out of luck on the TC . I can't see 600 and up for performance converter . Not sure what to do except go to the 10 3/4 157 flex and a hammer . thanks
Click to expand...
It looks like a used converter or donor car is your only choice if you stay with an automatic, or try to shoehorn in a larger bellhousing. Why not sell the V6 car and buy a V8 car?
 

LILCBRA

I wish I didn't have all of these balls in the air
Mod Dude
Dec 6, 2005
6,517
5,512
194
Corn County USA
Friday at 1:33 AM
#67
  • Friday at 1:33 AM
  • #67
One thought - maybe check with transmission shops to see if they can't locate one for you. With any luck they'll have some source somewhere that the general public isn't aware of.
 

welder4956

20+ Year Stangneter
Nov 28, 2003
251
116
53
Birmingham, AL
Friday at 10:24 AM
#68
  • Friday at 10:24 AM
  • #68
These folks have a pretty comprehensive listing of the different torque converters available for C4 transmissions with their dimensions. There are a few that are close to the Mustang II dimensions, but just slightly larger or have different pilot hub dimensions. The #2512 for the 2.8L/170, 3.3L/200, Maverick, Fairmont, Zephyr, Mustang is awful close. Their listing does not show what is in stock, so you might contact them to see if they have a Mustang II converter.

https://gopnh.com/Ford-Transmissions/C4
 
D

dulcimerbob

Member
Aug 25, 2026
31
23
18
GA
Friday at 7:20 PM
#69
  • Friday at 7:20 PM
  • #69
welder4956 said:
It looks like a used converter or donor car is your only choice if you stay with an automatic, or try to shoehorn in a larger bellhousing. Why not sell the V6 car and buy a V8 car?
Click to expand...
And spoil all my fun ???
 
Reactions: welder4956
D

dulcimerbob

Member
Aug 25, 2026
31
23
18
GA
Saturday at 6:30 PM
#70
  • Saturday at 6:30 PM
  • #70
dulcimerbob said:
And spoil all my fun ???
Click to expand...
Considering a t-5 swap . I'd rather have a stick anyway. This week I plan to pull the old 2.8/C4 . I looked into just building the v6 but the parts are expensive and you wouldn't have much to show for it . The old c4 may be toast anyway . The saga continues .
 
Reactions: welder4956 and LILCBRA
Prev
  • 1
  • 2
  • 3
  • 4
First Prev 4 of 4
You must log in or register to reply here.

Similar threads

F
Electrical Foxbody wiring harness 2.3 to v8 swap
  • Foxbodyjake
  • Mar 23, 2026
  • Fox 5.0 Mustang Tech
  • 2
Replies
26
Views
1K
Fox 5.0 Mustang Tech Sep 7, 2026
Kleinjj27
K
K
3.8 T5 & Bellhousing to 1987 Lincoln 5.0
  • ks65stang
  • Mar 2, 2026
  • Other Auto Tech
Replies
3
Views
455
Other Auto Tech Mar 3, 2026
Noobz347
J
1996 v6-v8 swap
  • jujuonurmom
  • Oct 28, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
0
Views
239
1996 - 2004 SN95 Mustang -General/Talk- Oct 28, 2025
jujuonurmom
J
0
V6 to V8 Swap info
  • 02_2v_Curtis
  • Jan 11, 2026
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
0
Views
904
1996 - 2004 SN95 Mustang -General/Talk- Jan 11, 2026
02_2v_Curtis
0
R
Transmission for manual swapping a 1994-1995 GT
  • Rembrant
  • Jul 11, 2025
  • 1994 - 1995 Specific Tech
Replies
2
Views
1K
1994 - 1995 Specific Tech Jul 13, 2025
Rembrant
R
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1974 - 1978 Mustang II Talk & Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?