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l98 tpi vs lt1 swap in 280zx

PostPosted: June 21st, 2014, 3:45 pm
by 280zxSheik
Unfortunately I have had a sudden change in my financial situation and I need to abruptly change the direction of my 1983 datsun 280zx build. If I'm to keep my Z it needs to be running by the end of summer.
(****Please be patient with me since I haven’t been exposed to the v8 280zx in about 10yrs so I might be a lil rusty.***)

I'm looking to do a lt1or tpi l98, 4l60/700r4 swap into my 280zx running, for reliability, aftermarket support and ease of swap which option and combination is preferable? Considering emissions aren't a issue which headers fit the sbc swapped 280zx best? If I converted to manual steering would this resolve header clearance issues? I head a rumor that the lt1 headers fit best. Which oil pan has the best clearances? I'm looking to use the jtr motor and trans mount. Is there any literature I should read that can make this swap easier?

I have 2 spare 4l60 transmissions from v6 fbodys, if I can save $$ on a transmission purchase i'd like to reuse one of these but will theses be adequate to handle the v8 torque. For cooling I have a l28et radiator & 1.9 ford escort wagon electric fan. I'm using the walbro 255lph FP and I have an after market trans cooler. I have three r200ln diffs w/lsd, one has 336 gears, one has 354 and the last has 390. I'll be running aftermarket gauges.

Parts I'm looking for are manual rack & pinion
Any used swap stuff, aftermarket gauges, used headers, z31 300zx drive-shaft, z31 4 lug rear suspension.

Re: l98 tpi vs lt1 swap in 280zx

PostPosted: June 21st, 2014, 3:58 pm
by grumpyvette

Re: l98 tpi vs lt1 swap in 280zx

PostPosted: June 21st, 2014, 7:22 pm
by philly
im going to be dropping a genIII motor in my 280 so i can only give you advice by eye balling... to avoid the steering rack i think lt1 corvette manifolds are the easiest choice, being as they dump straight down at the back of the motor. i think dropping in a tpi setup would be good and bad for the same reason... i like that it has a distributor and not an optispark, but its a chevy so the distributor is out back and you may have to use hood pins and do away with your stock latch setup (depending on how far back you push your motor.) also all the parts are cheaper for a traditional small block than for an lt1 especially the cooling system.

Re: l98 tpi vs lt1 swap in 280zx

PostPosted: June 21st, 2014, 7:24 pm
by philly
by the way no R200 LSD came from the factory with those final drive ratios... you may have R200's with those gears, but no LSD...

Re: l98 tpi vs lt1 swap in 280zx

PostPosted: June 21st, 2014, 7:28 pm
by philly
those transmissions will get you on the road and running but they are not going to take much abuse in stock form... however you should get great service from them if you are just using the car as transportation and not beating the snot out of it.

Re: l98 tpi vs lt1 swap in 280zx

PostPosted: June 21st, 2014, 8:33 pm
by 87vette81big
The V8 & V6 4L60E Transmissions are similar.
The main difference is the 3-4 clutch drum setup possible.
Only way to know for sure is to tear it down.
Want the 6-disc friction setup at least.
Depending where you live I can rebuild it for you.
Truck frieght shipping or Fed Ex Freight shipping would make it affordable both ways & back to you
If broke use as is. Gamble.
Sometimes have no choice if it must be running.

I'll be tryng to go l98

PostPosted: June 22nd, 2014, 3:46 pm
by 280zxSheik
Grumpy thank you for the links
Philly could i use lt1 vette manifolds on a tpi l98? Also the gear ratios are estimates cause its been awhile since i looked em up, but im certain they are lsd.

Re: I'll be tryng to go l98

PostPosted: June 22nd, 2014, 4:04 pm
by philly
280zxSheik wrote:Grumpy thank you for the links
Philly could i use lt1 vette manifolds on a tpi l98? Also the gear ratios are estimates cause its been awhile since i looked em up, but im certain they are lsd.



lt1, zz3, and zz4 heads are D ports.. i dont know if they are compatible with earlier heads... it may be worth checking out if early c4 vette tpi headers exit the same way.

Re: I'll be tryng to go l98

PostPosted: June 22nd, 2014, 4:05 pm
by philly
280zxSheik wrote:Grumpy thank you for the links
Philly could i use lt1 vette manifolds on a tpi l98? Also the gear ratios are estimates cause its been awhile since i looked em up, but im certain they are lsd.



lt1, zz3, and zz4 heads are D ports.. i dont know if they are compatible with earlier heads... it may be worth checking out if early c4 vette tpi headers exit the same way.

Re: l98 tpi vs lt1 swap in 280zx

PostPosted: June 22nd, 2014, 5:00 pm
by 280zxSheik
Later l98s have D port heads, so the lt1 manifolds would fit them.

Re: l98 tpi vs lt1 swap in 280zx

PostPosted: June 22nd, 2014, 5:25 pm
by philly
280zxSheik wrote:Later l98s have D port heads, so the lt1 manifolds would fit them.


right on then there ya go!

Re: l98 tpi vs lt1 swap in 280zx

PostPosted: June 25th, 2014, 12:18 am
by 280zxSheik
Has anyone used the Vortec 350 vs the regular l98 TPI?

Re: l98 tpi vs lt1 swap in 280zx

PostPosted: June 25th, 2014, 7:35 am
by grumpyvette

Re: l98 tpi vs lt1 swap in 280zx

PostPosted: July 16th, 2014, 12:55 pm
by grumpyvette
Id point out that one factor many guys over look that you constantly hear about the "MASSIVE TORQUE"
the most powerful TPI was the 1991 version
"In the 1991 Chevrolet Corvette, the L98 has a compression ratio of 9.5-to-1. Compression ratio lists the difference between the largest capacity of a cylinder and the smallest capacity, as the piston moves from bottom dead center on the crank stroke to top dead center on the crank stroke. In this engine, the mildly high compression ratios (considering the crappy gas available) mean that the engine could produce 245 horsepower at 4,000 rpm and 340 lb.-feet of torque at 3,200 rpm."

the LT4 only made 330hp/340ft lbs of torque
http://www.corvetteactioncenter.com/spe ... t1lt4.html

both engines are PITIFULLY WEAK compared to what you can build from a basic SBC

HERES SOME EXAMPLES

viewtopic.php?f=69&t=3814

viewtopic.php?f=44&t=38

viewtopic.php?f=87&t=10377&p=42862&hilit=215cc+vortec#p42862

http://www.airflowresearch.com/articles ... /A-P1.html

http://www.airflowresearch.com/articles ... 5/A-P1.htm

http://www.airflowresearch.com/articles ... 1/A-P1.htm

viewtopic.php?f=55&t=10494

viewtopic.php?f=32&t=430

viewtopic.php?f=69&t=10152

viewtopic.php?f=69&t=7771

viewtopic.php?f=52&t=5078

viewtopic.php?f=69&t=1040&p=1943#p1943

Re: l98 tpi vs lt1 swap in 280zx

PostPosted: July 16th, 2014, 8:57 pm
by philly
judging by the quarter mile times when the lt4 came out i think the 340 was measured at the tire!

Re: l98 tpi vs lt1 swap in 280zx

PostPosted: July 17th, 2014, 8:15 am
by grumpyvette
yes its rear wheel hp, but that's still appallingly weak power numbers, compared to what can be accomplished with carefully selected and carefully assembled components especially if your not all that concerned with sticking to a 350 displacement limit, or overly concerned with low speed drive-ability,and mileage and emissions, like the engineers at G.M. were forced to be.
with todays components building an engine with at least 420-450 rear wheel hp is certainly within reach even to the average hobbiest.