<![CDATA[olds 307 to chevy 350 swap]]>I have a 84 olds delta 88 with a 307 in it. It has a 3 speed tranny, not sure if its the th200 or th350. I plan to swap a chevy crate 350 in it. Does anyone know how hard this will be? I would like to use the tranny thats in the car now if I can. I know the chevy 305 would be easy becasue the 305's and the 350's have the same blocks but old's are different. Has anyone done this swap before? What parts can I use on the 350?(distributor,manifolds,pullys,pumps,etc)Any help, ideas, or tips would be great. Thanks

]]>https://fargostreet.com/topic/8978/olds-307-to-chevy-350-swapRSS for NodeThu, 28 May 2026 21:26:27 GMTSun, 07 Jan 2007 00:57:52 GMT60<![CDATA[Reply to olds 307 to chevy 350 swap on Tue, 09 Jan 2007 01:44:36 GMT]]>ALL TH400's have the exact same size/spline count on the input side. The only other trans that used this size was a few select Muncie transmissions. Ex, M21 & M22 (rockcrusher).

]]>https://fargostreet.com/post/136746https://fargostreet.com/post/136746Tue, 09 Jan 2007 01:44:36 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Tue, 09 Jan 2007 00:46:10 GMT]]>Would the oldsmobile be different though than an impala? What spline is a th400? I've been looking and some say a 30or31. Thanks for all the help by the way.

]]>https://fargostreet.com/post/136736https://fargostreet.com/post/136736Tue, 09 Jan 2007 00:46:10 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Tue, 09 Jan 2007 00:02:28 GMT]]>

95tsi wrote:
Would I have to weld that on or does it just slip on? And does it just have to be a th400 yoke to fit? The driveshaft would be smaller wouldn't it?

You will need the yoke only. Find out what it came off of and go to your local napa and tell them you need a u joint with ends for each vehicle. Ex: 1974 Chevy C1500 with a 454/TH400 on one end and the year/impala on the other. I've done this countless times when i worked at napa.

]]>https://fargostreet.com/post/136729https://fargostreet.com/post/136729Tue, 09 Jan 2007 00:02:28 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Mon, 08 Jan 2007 23:45:29 GMT]]>Would I have to weld that on or does it just slip on? And does it just have to be a th400 yoke to fit? The driveshaft would be smaller wouldn't it?

]]>https://fargostreet.com/post/136724https://fargostreet.com/post/136724Mon, 08 Jan 2007 23:45:29 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Mon, 08 Jan 2007 02:27:29 GMT]]>

95tsi wrote:
Well I found a th400 tranny. Will it bolt-in in place of the th200?

Yup but you need a different driveshaft yoke. The th400 has a bigger input size than all the rest.

]]>https://fargostreet.com/post/136580https://fargostreet.com/post/136580Mon, 08 Jan 2007 02:27:29 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Mon, 08 Jan 2007 02:18:06 GMT]]>Well I found a th400 tranny. Will it bolt-in in place of the th200?

]]>https://fargostreet.com/post/136574https://fargostreet.com/post/136574Mon, 08 Jan 2007 02:18:06 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Sun, 07 Jan 2007 18:13:09 GMT]]>BPO 307 ftl but if you are getting rid of the block I'll take it off you're hands.......there are some top secret missions going on in the sprint car business with those blocks. Seriously let me know if you want it gone.

]]>https://fargostreet.com/post/136488https://fargostreet.com/post/136488Sun, 07 Jan 2007 18:13:09 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Sun, 07 Jan 2007 14:27:05 GMT]]>

tjamz wrote:
Ahh...I'll take the advice of wes here. The last Olds car I swapped a 350 into was a 1984 Cutlass (donor vehicle was a 1978 Chevy Pickup) and it pretty much bolted right in. I think we had one bolt on the bell housing that didn't line up, but all of the others did. The existing motor however, was not a 307 as is the case here, but was the 3.8 liter (I believe a buick motor). At any rate, I'd trust the advice that Wes provided here anyways. He's worked with them more than I have.

GM used 2 different 3.8 engines back then. one is the grandfather of the 3,8 of today, the 231 cu inch buick engine which will not bolt up. The other was a 229 cu inch Chevy engine which will bolt up close to the same. That's probably what you had in there Chuck.

]]>https://fargostreet.com/post/136468https://fargostreet.com/post/136468Sun, 07 Jan 2007 14:27:05 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Sun, 07 Jan 2007 12:11:42 GMT]]>Ahh...I'll take the advice of wes here. The last Olds car I swapped a 350 into was a 1984 Cutlass (donor vehicle was a 1978 Chevy Pickup) and it pretty much bolted right in. I think we had one bolt on the bell housing that didn't line up, but all of the others did. The existing motor however, was not a 307 as is the case here, but was the 3.8 liter (I believe a buick motor). At any rate, I'd trust the advice that Wes provided here anyways. He's worked with them more than I have.

]]>https://fargostreet.com/post/136466https://fargostreet.com/post/136466Sun, 07 Jan 2007 12:11:42 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Sun, 07 Jan 2007 07:20:23 GMT]]>

95tsi wrote:
Would it be benificial to get rid of the computer controlled carb and distributor for a vacuum advance dist.? Do you think it would be easier to just get a similar year impala?

Yes and Yes.

]]>https://fargostreet.com/post/136458https://fargostreet.com/post/136458Sun, 07 Jan 2007 07:20:23 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Sun, 07 Jan 2007 06:38:23 GMT]]>I have a q-jet carb. Would it be benificial to get rid of the computer controlled carb and distributor for a vacuum advance dist.? I might know of a wrecked caprice that could work as a donar car. Do you think it would be easier to just get a similar year impala? The one i know of I think has a 267 v8. I would do the same swap though. I will proably stick with the delta becasue I have it almost ready besides the motor swap. Thanks for the help but keep the opinions coming. Thanks again

]]>https://fargostreet.com/post/136457https://fargostreet.com/post/136457Sun, 07 Jan 2007 06:38:23 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Sun, 07 Jan 2007 05:01:22 GMT]]>Oh, one more thing. This is one of the first years that Olds used fuel injection with than vehicle/engine combo. it was available both F.I. and carb equipped. Verify what you have.

]]>https://fargostreet.com/post/136451https://fargostreet.com/post/136451Sun, 07 Jan 2007 05:01:22 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Sun, 07 Jan 2007 04:51:40 GMT]]>Wrong Chuck. Chevy is the odd duck of the GM fleet when it comes to bellhousings. You'll have to find a similar year GM car with a 305-350 for the donor stuff like mounts, pulleys, distributor, brackets, etc. The mounts also mounts on a Chevy engine are completely different and bolt into a different spot on the frame but, the holes should already be pre drilled so that shouldn't be a problem. You may need to get the p/s pump from the donor vehicle as well. the Olds bracket system is different than the Chevy and may not bolt up to the Chevy brackets properly. But for goodness sake, make sure your p/s pump is the same era of a vehicle. They switched to metric threads in the late 70's so an older pump will not work. one more thing, If memory serves me correctly, the fuel line is on the drivers side with the Olds engine and will have to re-routed to the passenger side when putting in a chevy engine. I could be wrong though. You may be fiddling around with the throttle cable too. I hope this helps a little.

]]>https://fargostreet.com/post/136449https://fargostreet.com/post/136449Sun, 07 Jan 2007 04:51:40 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Sun, 07 Jan 2007 03:37:32 GMT]]>Bell housing should fit between the two and if memory serves, you can use the motor mounts. GM is usually pretty interchangeable.

]]>https://fargostreet.com/post/136443https://fargostreet.com/post/136443Sun, 07 Jan 2007 03:37:32 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Sun, 07 Jan 2007 02:03:01 GMT]]>I would want to get a th350 becasue its going in an enduro car. I don't need overdrive. How do I tell for sure what model of tranny is in it? On the alluminum tag on it, it reads 84-01 263305. I don't know if that helps but it might. I don't have a motor yet but i know of a crate motor with like 30k on it. If I get a th350, will the drive shaft and everything else fit? Anyone know of a 350/th350 combo laying around?

]]>https://fargostreet.com/post/136423https://fargostreet.com/post/136423Sun, 07 Jan 2007 02:03:01 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Sun, 07 Jan 2007 01:57:23 GMT]]>do you already have a morotr? If not i would try to get a motor and tranny together. 90% you have a 200c in there, and it will not bolt up to a chevy. also if you can manage to score a 700r4 with a 350 from a 2wd pickup with accesories woud be great. I dont think any of the accesories will bolt up with out modifications. I am currently doing a 350 diesel to a olds 403 swap in a 81 Grand Prix. Also the motor mounts may have to be changed or at least moved.
Gary

]]>https://fargostreet.com/post/136422https://fargostreet.com/post/136422Sun, 07 Jan 2007 01:57:23 GMT<![CDATA[Reply to olds 307 to chevy 350 swap on Sun, 07 Jan 2007 01:08:32 GMT]]>i have a friend that did this to a cutlass all the pullys worked but to use the olds tranny you have to find a bell housing that fits the chevy motor to the olds tranny.. and i think thats all he had to do.not 100% tho

]]>https://fargostreet.com/post/136392https://fargostreet.com/post/136392Sun, 07 Jan 2007 01:08:32 GMT